14.10 Performance of the Codec Mode Request Generation for Adaptive Multi-Rate Codecs
3GPP51.010-1Mobile Station (MS) conformance specificationPart 1: Conformance specificationTS
14.10.1 Performance of the Codec Mode Request Generation – TCH/AFS
14.10.1.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.1.2 Conformance Requirement
For TULow channel conditions with ideal frequency hopping without DTX activated, the MS shall produce Codec Mode Requests with the following accuracy:
Requirement 1: When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
Requirement 2: When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the fixed normalization factor defined in sub-clause 3.3.1 of TS 45.009 to account for potential improved receiver performances.
NOTE: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.05 subclause 2:
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
14.10.1.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement 1 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To verify that the MS does not exceed conformance requirement 2 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
3. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
14.10.1.4 Method of Test
14.10.1.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a TCH/AFS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.2 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements:
–
PIXIT Statements:
– AMR C/I normalization factor.
14.10.1.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_4 |
10,2 |
CODEC_MODE_3 |
7.4 |
CODEC_MODE_2 |
6,7 |
CODEC_MODE_1 |
5,15 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the highest of the downwards thresholds Thr1d. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the lowest of the downwards thresholds Thr2d. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the lowest of the upwards thresholds Thr2u. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the highest of the upwards thresholds Thr1u. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.2 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.2 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_4 |
10,2 |
CODEC_MODE_3 |
7.4 |
CODEC_MODE_2 |
6,7 |
CODEC_MODE_1 |
5,15 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 11.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 5.5 dB |
Thr1u = 13.5 dB |
CODEC_MODE_1 |
|
Thr2u = 7.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
2c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 7.95 kbit/s mode only:
The SS switches the downlink codec to the 7.95 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 13.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 7.5 dB |
Thr1u = 15.5 dB |
CODEC_MODE_1 |
|
Thr2u = 9.5 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
3e) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 10.2 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 10.2 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
4c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes (GSM850, GSM900, DCS1800, PCS1900).
14.10.1.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.2 Performance of the Codec Mode Request Generation – TCH/AHS
14.10.2.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.2.2 Conformance Requirement
For TULow channel conditions with ideal frequency hopping without DTX activated, the MS shall produce Codec Mode Requests with the following accuracy:
Requirement 1: When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
Requirement 2: When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the fixed normalization factor defined in sub-clause 3.3.1 of TS 45.009 to account for potential improved receiver performances.
NOTE: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.05 subclause 2:
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
14.10.2.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement 1 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To verify that the MS does not exceed conformance requirement 2 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
3. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in ether an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or and in a AMR_CONFIG_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
14.10.2.4 Method of Test
14.10.2.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a TCH/AHS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 7.95 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements:
–
PIXIT Statements:
– AMR C/I normalization factor.
14.10.2.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_4 |
7.4 |
CODEC_MODE_3 |
6.7 |
CODEC_MODE_2 |
5.15 |
CODEC_MODE_1 |
4.75 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 14.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.0 dB |
Thr1u = 16.0 dB |
CODEC_MODE_1 |
|
Thr2u = 12.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 1 second.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the highest of the downwards thresholds Thr1d. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the lowest of the downwards thresholds Thr2d. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the lowest of the upwards thresholds Thr2u. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the highest of the upwards thresholds Thr1u. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 7.95 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1o) The SS repeat steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases samples have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then send an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_4 |
7.4 |
CODEC_MODE_3 |
6.7 |
CODEC_MODE_2 |
5.15 |
CODEC_MODE_1 |
4.75 |
With the Initial Codec Mode set to any mode.
and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 13.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 9 dB |
Thr1u = 15.0 dB |
CODEC_MODE_1 |
|
Thr2u = 11.0 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
2c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 6.7 kbit/s mode only:
The SS switches the downlink codec to the 6.7 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 15.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 11.0 dB |
Thr1u = 17.0 dB |
CODEC_MODE_1 |
|
Thr2u = 13.0 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
3e) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 5.15 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 5.15 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 14.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.0 dB |
Thr1u = 16.0 dB |
CODEC_MODE_1 |
|
Thr2u = 12.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
4c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes (GSM850, GSM900, DCS1800, PCS1900).
14.10.2.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.3 Performance of the Codec Mode Request Generation – TCH/AFS – improved RX
14.10.3.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.3.2 Conformance Requirement
For TULow channel conditions with ideal frequency hopping without DTX activated, the MS shall produce Codec Mode Requests with the following accuracy:
Requirement 1: When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
Requirement 2: When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
The above test levels shall be reduced by the normalization factor defined in sub-clause 3.3.1 of TS 45.009 to account for improved receiver performances, specified in 14.10.3.4.1 below.
NOTE: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.05 subclause 2:
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
14.10.3.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement 1 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To verify that the MS does not exceed conformance requirement 2 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
3. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
NOTE: The C/I values used throughout this test have been carefully selected to ensure no values above 16dB are signalled, low C/I values will not conflict with the synchronisation requirements in TS 45.010, and also to ensure the C/I values are shared between upward and downward applications. Any future modification or Change Request on this section should take into account these aspects.
14.10.3.4 Method of Test
14.10.3.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a TCH/AFS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.2 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements:
–
PIXIT Statements:
– AMR C/I normalization factors (AFS DARP) as follows:
Required additional information PIXIT |
CI_NORM_AFS_DARP_2dB |
CI_NORM_AFS_DARP_3dB |
CI_NORM_AFS_DARP_4dB |
CI_NORM_AFS_DARP_6dB |
CI_NORM_AFS_DARP_8dB |
CI_NORM_AFS_DARP_10dB |
CI_NORM_AFS_DARP_11dB |
CI_NORM_AFS_DARP_12dB |
CI_NORM_AFS_DARP_14dB |
CI_NORM_AFS_DARP_17dB |
CI_NORM_AFS_DARP_19dB |
CI_NORM_AFS_DARP_20dB |
14.10.3.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_4 |
10,2 |
CODEC_MODE_3 |
7.4 |
CODEC_MODE_2 |
6,7 |
CODEC_MODE_1 |
5,15 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 15.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.0 dB |
Thr1u = 15.0 dB |
CODEC_MODE_1 |
|
Thr2u = 6.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set Thr1u + 4dB – CI_NORM_AFS_DARP_19dB. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AFS_DARP_11dB. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_2dB. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_10dB. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_19dB. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.2 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.2 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_4 |
10,2 |
CODEC_MODE_3 |
7.4 |
CODEC_MODE_2 |
6,7 |
CODEC_MODE_1 |
5,15 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 8.0 dB |
Thr1u = 13.0 dB |
CODEC_MODE_1 |
|
Thr2u = 8.0 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AFS_DARP_17dB. The SS waits 500ms
2c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AFS_DARP_8dB. The SS increments the counter for ‘C/I decreases below thresholds’.
2d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
2e) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
2f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_4dB. The SS increments the counter for ‘C/I decreases below thresholds’.
2g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
2h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
2i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_12dB. The SS increments the counter for ‘C/I increases above thresholds’.
2j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
2k) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
2l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_17dB. The SS increments the counter for ‘C/I increases above thresholds’.
2m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.2 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
2n) The SS switches the downlink codec mode to 12.2 kbit/s and waits for 0.5s.
2o) The SS repeats steps 2c) to 2n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 7.95 kbit/s mode only:
The SS switches the downlink codec to the 7.95 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 14.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.0 dB |
Thr1u = 16.0 dB |
CODEC_MODE_1 |
|
Thr2u = 10.0 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AFS_DARP_20dB. The SS waits 500ms
3e) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AFS_DARP_10dB. The SS increments the counter for ‘C/I decreases below thresholds’.
3f) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
3g) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
3h) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_6dB. The SS increments the counter for ‘C/I decreases below thresholds’.
3i) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
3j) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
3k) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_14dB. The SS increments the counter for ‘C/I increases above thresholds’.
3l) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
3m) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
3n) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_20dB. The SS increments the counter for ‘C/I increases above thresholds’.
3o) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.2 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
3p) The SS switches the downlink codec mode to 12.2 kbit/s and waits for 0.5s.
3q) The SS repeats steps 3e) to 3p) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 10.2 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 10.2 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AFS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 16.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 7.0 dB |
Thr1u = 16.0 dB |
CODEC_MODE_1 |
|
Thr2u = 7.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AFS_DARP_20dB. The SS waits 500ms
4c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AFS_DARP_12dB. The SS increments the counter for ‘C/I decreases below thresholds’.
4d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
4e) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
4f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_3dB. The SS increments the counter for ‘C/I decreases below thresholds’.
4g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
4h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
4i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_11dB. The SS increments the counter for ‘C/I increases above thresholds’.
4j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
4k) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
4l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_20dB. The SS increments the counter for ‘C/I increases above thresholds’.
4m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.2 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
4n) The SS switches the downlink codec mode to 12.2 kbit/s and waits for 0.5s.
4o) The SS repeats steps 4c) to 4n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes (GSM850, GSM900, DCS1800, PCS1900).
14.10.3.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.4 Performance of the Codec Mode Request Generation – TCH/AHS – improved RX
14.10.4.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.4.2 Conformance Requirement
For TULow channel conditions with ideal frequency hopping without DTX activated, the MS shall produce Codec Mode Requests with the following accuracy:
Requirement 1: When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
Requirement 2: When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
The above test levels shall be reduced by the normalization factor defined in sub-clause 3.3.1 of TS 45.009 to account for improved receiver performances, specified in 14.10.3.4.1 below.
NOTE: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.05 subclause 2:
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
14.10.4.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement 1 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To verify that the MS does not exceed conformance requirement 2 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
3. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in ether an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or and in a AMR_CONFIG_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
NOTE: The C/I values used throughout this test have been carefully selected to ensure no values above 16dB are signalled, low C/I values will not conflict with the synchronisation requirements in TS 45.010, and also to ensure the C/I values are shared between upward and downward applications. Any future modification or Change Request on this section should take into account these aspects.
14.10.4.4 Method of Test
14.10.4.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a TCH/AHS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 7.95 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements:
–
PIXIT Statements:
– AMR C/I normalization factors (AHS DARP) as follows:
Required additional information PIXIT |
CI_NORM_AHS_DARP_4dB |
CI_NORM_AHS_DARP_6dB |
CI_NORM_AHS_DARP_7dB |
CI_NORM_AHS_DARP_10dB |
CI_NORM_AHS_DARP_12dB |
CI_NORM_AHS_DARP_13dB |
CI_NORM_AHS_DARP_16dB |
CI_NORM_AHS_DARP_17dB |
CI_NORM_AHS_DARP_20dB |
CI_NORM_AHS_DARP_21dB |
14.10.4.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_4 |
7.4 |
CODEC_MODE_3 |
6.7 |
CODEC_MODE_2 |
5.15 |
CODEC_MODE_1 |
4.75 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 14.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 8.0 dB |
Thr1u = 16.0 dB |
CODEC_MODE_1 |
|
Thr2u = 9.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AHS_DARP_20dB. The SS waits 1 second.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AHS_DARP_10dB. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AHS_DARP_4dB. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AHS_DARP_13dB. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AHS_DARP_20dB. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 7.95 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1o) The SS repeat steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases samples have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then send an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_4 |
7.4 |
CODEC_MODE_3 |
6.7 |
CODEC_MODE_2 |
5.15 |
CODEC_MODE_1 |
4.75 |
With the Initial Codec Mode set to any mode.
and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 14.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 8 dB |
Thr1u = 16.0 dB |
CODEC_MODE_1 |
|
Thr2u = 8.0 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AHS_DARP_20dB. The SS waits 500ms
2c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AHS_DARP_10dB. The SS increments the counter for ‘C/I decreases below thresholds’.
2d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
2e) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
2f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AHS_DARP_4dB. The SS increments the counter for ‘C/I decreases below thresholds’.
2g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
2h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
2i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AHS_DARP_12dB. The SS increments the counter for ‘C/I increases above thresholds’.
2j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
2k) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
2l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AHS_DARP_20dB. The SS increments the counter for ‘C/I increases above thresholds’.
2m) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 7.95 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
2n) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
2o) The SS repeats steps 2c) to 2n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 6.7 kbit/s mode only:
The SS switches the downlink codec to the 6.7 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 16.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 11.0 dB |
Thr1u = 17.0 dB |
CODEC_MODE_1 |
|
Thr2u = 13.0 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AHS_DARP_21dB. The SS waits 500ms
3e) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AHS_DARP_12dB. The SS increments the counter for ‘C/I decreases below thresholds’.
3f) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
3g) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
3h) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AHS_DARP_7dB. The SS increments the counter for ‘C/I decreases below thresholds’.
3i) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
3j) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
3k) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AHS_DARP_17dB. The SS increments the counter for ‘C/I increases above thresholds’.
3l) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
3m) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
3n) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AHS_DARP_21dB. The SS increments the counter for ‘C/I increases above thresholds’.
3o) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 7.95 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
3p) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
3q) The SS repeats steps 3e) to 3p) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 5.15 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 5.15 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/AHS in kbit/s |
CODEC_MODE_3 |
7.95 |
CODEC_MODE_2 |
6.7 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 7.95 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 17.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.0 dB |
Thr1u = 17.0 dB |
CODEC_MODE_1 |
|
Thr2u = 12.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 7.95 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr1u + 4dB – CI_NORM_AHS_DARP_21dB. The SS waits 500ms
4c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr1d – 4dB – CI_NORM_AHS_DARP_13dB. The SS increments the counter for ‘C/I decreases below thresholds’.
4d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
4e) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
4f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AHS_DARP_6dB. The SS increments the counter for ‘C/I decreases below thresholds’.
4g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
4h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
4i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AHS_DARP_16dB. The SS increments the counter for ‘C/I increases above thresholds’.
4j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.7 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
4k) The SS switches the downlink codec mode to 6.7 kbit/s and waits for 0.5s.
4l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AHS_DARP_21dB. The SS increments the counter for ‘C/I increases above thresholds’.
4m) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 7.95 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
4n) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
4o) The SS repeats steps 4c) to 4n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes (GSM850, GSM900, DCS1800, PCS1900).
14.10.4.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.5 Performance of the Codec Mode Request Generation – O-TCH/AHS
14.10.5.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.5.2 Conformance Requirement
For TULow channel conditions with ideal frequency hopping without DTX activated, the MS shall produce Codec Mode Requests with the following accuracy:
Requirement 1: When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
Requirement 2: When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the fixed normalization factor defined in sub-clause 3.3.1 of TS 45.009 to account for potential improved receiver performances.
NOTE: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.05 subclause 2:
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
14.10.5.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement 1 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To verify that the MS does not exceed conformance requirement 2 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
3. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
14.10.5.4 Method of Test
14.10.5.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a O-TCH/AHS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.2 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements:
–
PIXIT Statements:
– AMR C/I normalization factor.
14.10.5.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/AHS in kbit/s |
CODEC_MODE_4 |
10,2 |
CODEC_MODE_3 |
7.4 |
CODEC_MODE_2 |
6,7 |
CODEC_MODE_1 |
5,15 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/AHS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the highest of the downwards thresholds Thr1d. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the lowest of the downwards thresholds Thr2d. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 4.75 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 4.75 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the lowest of the upwards thresholds Thr2u. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 7.95 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 7.95 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the highest of the upwards thresholds Thr1u. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.2 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.2 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/AHS in kbit/s |
CODEC_MODE_4 |
10,2 |
CODEC_MODE_3 |
7.4 |
CODEC_MODE_2 |
6,7 |
CODEC_MODE_1 |
5,15 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
+ |
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/AHS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 11.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 5.5 dB |
Thr1u = 13.5 dB |
CODEC_MODE_1 |
|
Thr2u = 7.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
2c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 7.95 kbit/s mode only:
The SS switches the downlink codec to the 7.95 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/AHS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 13.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 7.5 dB |
Thr1u = 15.5 dB |
CODEC_MODE_1 |
|
Thr2u = 9.5 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
3e) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 10.2 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 10.2 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/AHS in kbit/s |
CODEC_MODE_3 |
12,2 |
CODEC_MODE_2 |
7.95 |
CODEC_MODE_1 |
4,75 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.2 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
4c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes (GSM850, GSM900, DCS1800, PCS1900).
14.10.5.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.6 Performance of the Codec Mode Request Generation – O-TCH/WFS
14.10.6.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.6.2 Conformance Requirement
For TU3 channel conditions with ideal frequency hopping without DTX activated in GSM900 and GSM850, the MS shall produce Codec Mode Requests with the following accuracy:
– When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
– When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the normalization factor defined in sub-clause 3.3.1 to account for potential improved receiver performances.
For other frequency bands, the propagation profile should be adjusted to: TU1.5 for DCS1800 and PCS1900, TU6 for GSM400 and TU3.6 for GSM700.
NOTE 1: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.009, subclause 3.3.3.3
14.10.6.3 Test Purpose
1. To verify that the MS does not exceed the conformance requirements (for producing codec request) under TU High and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
14.10.6.4 Method of Test
14.10.6.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a O-TCH/WFS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.65 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TU High.
NOTE 1: The fading characteristics shall be TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700..
Specific PICS Statements:
–
PIXIT Statements:
– O-TCH/F C/I normalisation factor
14.10.6.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/WFS in kbit/s |
CODEC_MODE_4 |
23,85 |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_4 |
Thr1d = 17.5 dB |
|
CODEC_MODE_3 |
Thr2d = 14.5 dB |
Thr1u = 19.5 dB |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
Thr2u = 16.5 dB |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
|
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the highest of the downwards thresholds Thr1d. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the lowest of the downwards thresholds Thr2d. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the lowest of the upwards thresholds Thr2u. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the highest of the upwards thresholds Thr1u. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/WFS in kbit/s |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
|
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 11.5 dB |
|
CODEC_MODE_2 |
Thr2d = 5.5 dB |
Thr1u = 13.5 dB |
CODEC_MODE_1 |
|
Thr2u = 7.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
2c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 8.85 kbit/s mode only:
The SS switches the downlink codec to the 8.85 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
|
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 13.5 dB |
|
CODEC_MODE_2 |
Thr2d = 7.5 dB |
Thr1u = 15.5 dB |
CODEC_MODE_1 |
|
Thr2u = 9.5 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
3e) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
– The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 8.85 kbit/s mode only:
– The SS waits for the MS to change the uplink codec to the 8.85 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
|
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
4c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes.
14.10.6.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.7 Performance of the Codec Mode Request Generation – O-TCH/WHS
14.10.7.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.7.2 Conformance Requirement
For TULow channel conditions with ideal frequency hopping without DTX activated, the MS shall produce Codec Mode Requests with the following accuracy:
Requirement 1: When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
Requirement 2: When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the fixed normalization factor defined in sub-clause 3.3.1 of TS 45.009 to account for potential improved receiver performances.
NOTE: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
14.10.7.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement 1 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To verify that the MS does not exceed conformance requirement 2 under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
3. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
14.10.7.4 Method of Test
14.10.7.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a O-TCH/WHS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.65 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700..
Specific PICS Statements:
–
PIXIT Statements:
– AMR C/I normalization factor.
14.10.7.4.2 Procedure
INITIAL CONFIG:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/WHS in kbit/s |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
+ |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/WHS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the highest of the downwards thresholds Thr1d. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the lowest of the downwards thresholds Thr2d. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the lowest of the upwards thresholds Thr2u. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the highest of the upwards thresholds Thr1u. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/WHS in kbit/s |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_2 |
Thr3d = 12.5 dB |
+ |
CODEC_MODE_1 |
|
Thr3u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/WHS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.2 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 11.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 5.5 dB |
Thr1u = 13.5 dB |
CODEC_MODE_1 |
|
Thr2u = 7.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
2c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 8.85 kbit/s mode only:
The SS switches the downlink codec to the 8.85 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
O-TCH/WHS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr1u = 20.5 dB |
CODEC_MODE_1 |
|
Thr2u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 13.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 7.5 dB |
Thr1u = 15.5 dB |
CODEC_MODE_1 |
|
Thr2u = 9.5 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
3e) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
– The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 8.85 kbit/s mode only:
– The SS waits for the MS to change the uplink codec to the 8.85 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
O-TCH/WHS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr1d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr1u = 14.5 dB |
CODEC_MODE_1 |
|
Thr2u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
4c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes (GSM850, GSM900, DCS1800, PCS1900).
14.10.7.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.8 Performance of the Codec Mode Request Generation – TCH/WFS
14.10.8.1 Definition
When a traffic channel supporting a WB-AMR speech codec is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.8.2 Conformance Requirement
For TU3 channel conditions with ideal frequency hopping without DTX activated in GSM900 and GSM850, the MS shall produce Codec Mode Requests with the following accuracy:
– When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
– When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the normalization factor defined in sub-clause 3.3.1 to account for potential improved receiver performances.
For other frequency bands, the propagation profile should be adjusted to: TU1.5 for DCS1800 and PCS1900, TU6 for GSM400 and TU3.6 for GSM700.
NOTE 1: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
3GPP TS 45.009 subclause 3.3.3.3
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
3GPP TS 45.005 subclause 2
14.10.8.3 Test Purpose
1. To verify that the MS does not exceed conformance requirement (for producing codec request) under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To implicitly verify the correct implementation of the WB-AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
14.10.8.4 Method of Test
14.10.8.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a TCH/WFS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.65 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements:
–
PIXIT Statements:
TCH/WFS C/I normalization factor
14.10.8.4.2 Procedure
STEP 1
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
18.5 dB |
+ |
CODEC_MODE_2 |
12.5 dB |
20.5 dB |
CODEC_MODE_1 |
|
14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr2u = 14.5 dB |
CODEC_MODE_1 |
|
Thr1u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr2u. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the highest of the downwards thresholds Thr1d. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to 4 dB below the lowest of the downwards thresholds Thr2d. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4dB above the lowest of the upwards thresholds Thr1u. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to 4 dB above the highest of the upwards thresholds Thr2u. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
18.5 dB |
+ |
CODEC_MODE_2 |
12.5 dB |
20.5 dB |
CODEC_MODE_1 |
|
14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 11.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 5.5 dB |
Thr2u = 13.5 dB |
CODEC_MODE_1 |
|
Thr1u = 7.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr2u. The SS waits 500ms
2c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 8.85 kbit/s mode only:
The SS switches the downlink codec to the 8.85 kbit/s mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr2u = 20.5 dB |
CODEC_MODE_1 |
|
Thr1u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 13.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 7.5 dB |
Thr2u = 15.5 dB |
CODEC_MODE_1 |
|
Thr1u = 9.5 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr1u. The SS waits 500ms
3e) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the AMR 8.85 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 8.85 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 12.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.5 dB |
Thr2u = 14.5 dB |
CODEC_MODE_1 |
|
Thr1u = 8.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to 4 dB above the highest of the upwards thresholds Thr2u. The SS waits 500ms
4c) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes.
14.10.8.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.
14.10.9 Performance of the Codec Mode Request Generation – TCH/WFS – improved RX
14.10.9.1 Definition
When a traffic channel supporting an Adaptive Multi-Rate speech codec version 5 is activated, the Codec Mode Request is sent by MS in band every other speech frame to indicate to the Network the recommended codec mode of the ACS to use on the downlink.
14.10.9.2 Conformance Requirement
3GPP TS 45.009 subclause 3.3.3.3:
For TU3 channel conditions with ideal frequency hopping without DTX activated in GSM900 and GSM850, the MS shall produce Codec Mode Requests with the following accuracy:
– When a carrier to interferer ratio 4 dB higher than a defined upper threshold is applied to the antenna connector, the MS shall request a higher mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
– When a carrier to interferer ratio 4 dB lower than a defined lower threshold is applied to the antenna connector, the MS shall request a lower mode with a probability exceeding 90%. This shall be measured immediately after a settling-time of 200 ms.
If required, the above test levels shall be reduced by the normalization factor defined in sub-clause 3.3.1 to account for potential improved receiver performances.
For other frequency bands, the propagation profile should be adjusted to: TU1.5 for DCS1800 and PCS1900, TU6 for GSM400 and TU3.6 for GSM700.
NOTE 1: Ideal frequency hopping assumes perfect decorrelation between bursts. For the propagation profile TU3, this is not easily achievable due to the high number of hopping frequencies required. Therefore, performance tests should be performed under ideal frequency hopping conditions for the following propagation profiles: TU50 for GSM900 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
NOTE 2: Receivers with improved performance may exceed the minimum requirements reflected by the normalisation factor defined in sub-clause 3.3.1. The normalisation factor, reflecting the improved performance, may depend on the carrier to interference ratio (C/I). Therefore, the conformance test of these receivers may require normalisation factors to be provided for each nominal C/I of the test.
3GPP TS 45.005 subclause 2:
For T-GSM 810 the requirements for GSM 900 shall apply, apart for those parameters for which a separate requirement exists.
14.10.9.3 Test Purpose
1. To verify that the MS does not exceed conformance requirements for producing codec mode request under TUHigh and frequency hopping propagation conditions without DTX with an allowance for the statistical significance of the test.
2. To implicitly verify the correct implementation of the AMR Thresholds and Hysteresis parameters received in either an ASSIGNMENT COMMAND or MODE MODIFY procedure, or through an AMR_CONFIG_REQ or THRESH_REQ message carried in a RATSCCH.
NOTE: This would normally be performed as a signalling test, however due to the complex layer 1 requirements it is verified here. Any future modification or Change Request on this section should take into account this additional test objective.
NOTE: The C/I values used throughout this test have been carefully selected to ensure no values above 16dB are signalled, low C/I values will not conflict with the synchronisation requirements in TS 45.010, and also to ensure the C/I values are shared between upward and downward applications. Any future modification or Change Request on this section should take into account these aspects.
14.10.9.4 Method of Test
14.10.9.4.1 Initial conditions
A call is set up according to the generic call set up procedure on a TCH/WFS with a hopping pattern in the Mid ARFCN range and covering at least 10 frequencies not exceeding 5 MHz. DTX shall not be activated. Power control level shall be set to maximum power.
The initial configuration indicates the use of the 12.65 mode of AMR only.
The SS transmits Standard Test Signal C1 on the traffic channel.
In addition to the wanted signal, the SS produces an independent, uncorrelated interfering signal, Standard Test Signal I1 (unwanted signal).
– The unwanted signal is continuous and has no fixed relationship with the bit transitions of the wanted signal. Initially, the unwanted signal is switched off.
– The fading characteristic of the wanted and the interfering signal is TUHigh.
NOTE 1: The fading characteristics shall be TU50 for GSM900, T-GSM 810 and GSM850, TU25 for DCS1800 and PCS1900, TU100 for GSM400, and TU60 for GSM700.
Specific PICS Statements
–
PIXIT Statements
TCH/WFS C/I normalization factors (TCH/WFS DARP) as follows:
Required additional information (PIXIT) |
CI_NORM_WFS_DARP_2dB |
CI_NORM_WFS_DARP_3dB |
CI_NORM_WFS_DARP_4dB |
CI_NORM_WFS_DARP_6dB |
CI_NORM_WFS_DARP_8dB |
CI_NORM_WFS_DARP_10dB |
CI_NORM_WFS_DARP_11dB |
CI_NORM_WFS_DARP_12dB |
CI_NORM_WFS_DARP_14dB |
CI_NORM_WFS_DARP_17dB |
CI_NORM_WFS_DARP_19dB |
CI_NORM_WFS_DARP_20dB |
14.10.9.4.2 Procedure
STEP 1:
1a) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With Initial Codec Mode unspecified, thus the default ICM rule being used and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 17.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 12.5 dB |
Thr2u = 19.5 dB |
CODEC_MODE_1 |
|
Thr1u = 14.5 dB |
The SS uses the expected Initial Codec Mode (default rule) after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode (default rule).
1b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 15.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 6.0 dB |
Thr2u = 15.0 dB |
CODEC_MODE_1 |
|
Thr1u = 6.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set Thr2u + 4dB – CI_NORM_AFS_DARP_19dB. The SS waits 500ms.
1c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr3d – 4dB – CI_NORM_AFS_DARP_11dB. The SS increments the counter for ‘C/I decreases below thresholds’.
1d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1e) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_2dB. The SS increments the counter for ‘C/I decreases below thresholds’.
1g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
1h) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
1i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_10dB. The SS increments the counter for ‘C/I increases above thresholds’.
1j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1k) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
1l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_19dB. The SS increments the counter for ‘C/I increases above thresholds’.
1m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
1n) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
1o) The SS repeats steps 1c) to 1n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 2:
2a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to any mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 17.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 12.5 dB |
Thr2u = 19.5 dB |
CODEC_MODE_1 |
|
Thr1u = 14.5 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
2b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 12.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 8.0 dB |
Thr2u = 13.0 dB |
CODEC_MODE_1 |
|
Thr1u = 8.0 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr2u + 4dB – CI_NORM_AFS_DARP_17dB. The SS waits 500ms
2c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr3d – 4dB – CI_NORM_AFS_DARP_8dB. The SS increments the counter for ‘C/I decreases below thresholds’.
2d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
2e) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
2f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_4dB. The SS increments the counter for ‘C/I decreases below thresholds’.
2g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
2h) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
2i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_12dB. The SS increments the counter for ‘C/I increases above thresholds’.
2j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
2k) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
2l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_17dB. The SS increments the counter for ‘C/I increases above thresholds’.
2m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
2n) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
2o) The SS repeats steps 2c) to 2n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 3:
3a) The unwanted signal is removed.
The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the AMR 8.85 kbit/s mode only:
The SS switches the downlink codec to the 8.85 mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested codec. The SS waits for the MS to change the uplink codec to the expected codec, 12 frames after receiving the ACK_OK message.
3b) The SS uses a Channel Mode Modify procedure to change the active codec set to the following set:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 18.5 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.5 dB |
Thr2u = 20.5 dB |
CODEC_MODE_1 |
|
Thr1u = 12.5 dB |
The SS switches the downlink codec to the Initial Codec Mode after sending the mode modify message and commands the MS through the CMC field to use the Initial Codec Mode as well. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
3c) The SS then sends a THRESH_REQ through a RATSCCH message commanding the MS to modify the Thresholds and Hysteresis to the following values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 14.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 10.0 dB |
Thr2u = 16.0 dB |
CODEC_MODE_1 |
|
Thr1u = 10.0 dB |
The SS waits 12 frames after receiving the ACK_OK message.
3d) The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr2u + 4dB – CI_NORM_AFS_DARP_20dB. The SS waits 500ms
3e) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr3d – 4dB – CI_NORM_AFS_DARP_10dB. The SS increments the counter for ‘C/I decreases below thresholds’.
3f) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
3g) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
3h) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_6dB. The SS increments the counter for ‘C/I decreases below thresholds’.
3i) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
3j) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
3k) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_14dB. The SS increments the counter for ‘C/I increases above thresholds’.
3l) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
3m) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
3n) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_20dB. The SS increments the counter for ‘C/I increases above thresholds’.
3o) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
3p) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
3q) The SS repeats steps 3e) to 3p) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
STEP 4:
4a) The unwanted signal is removed.
The SS uses a Channel Mode Modify procedure commanding the MS to use the WFS 8.85 kbit/s mode only:
The SS waits for the MS to change the uplink codec to the 8.85 kbit/s mode.
4b) The SS then sends an AMR_CONF_REQ through a RATSCCH message commanding the MS to use the following ACS:
Codec Mode |
TCH/WFS in kbit/s |
CODEC_MODE_3 |
12,65 |
CODEC_MODE_2 |
8,85 |
CODEC_MODE_1 |
6,6 |
With the Initial Codec Mode set to the 12.65 kbit/s mode and the following decision thresholds and hysteresis values:
MC’/MR’ |
THR_MC_Dn(MC)/ |
THR_MC_Up(MC)/ |
CODEC_MODE_3 |
Thr3d = 16.0 dB |
+ |
CODEC_MODE_2 |
Thr2d = 7.0 dB |
Thr2u = 16.0 dB |
CODEC_MODE_1 |
|
Thr1u = 7.0 dB |
The SS switches the downlink codec to the Initial Codec Mode 12 frames after sending the AMR_CONF_REQ message and commands the MS through the CMC field to use the requested Initial Codec Mode. The SS waits for the MS to change the uplink codec to the expected Initial Codec Mode, 12 frames after receiving the ACK_OK message.
The SS waits until the MS indicates in the CMR that the 12.65 kbit/s is the recommended downlink codec mode.
If the MS never reaches that point then the test is failed.
The downlink radio environment is altered so that the carrier to interference ratio is set to Thr2u + 4dB – CI_NORM_AFS_DARP_20dB. The SS waits 500ms
4c) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr3d – 4dB – CI_NORM_AFS_DARP_12dB. The SS increments the counter for ‘C/I decreases below thresholds’.
4d) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a lower codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
4e) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
4f) The downlink radio environment is altered so that the carrier to interference ratio is reduced to Thr2d – 4dB – CI_NORM_AFS_DARP_3dB. The SS increments the counter for ‘C/I decreases below thresholds’.
4g) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 6.6 kbits/s codec mode in the downlink, then the SS should increment the successful C/I decrease event counter. Otherwise, the SS should increment the unsuccessful C/I decrease event counter.
4h) The SS switches the downlink codec mode to 6.6 kbit/s and waits for 0.5s.
4i) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr1u + 4dB – CI_NORM_AFS_DARP_11dB. The SS increments the counter for ‘C/I increases above thresholds’.
4j) The SS checks the CMR received from the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use the 8.85 kbit/s or a higher codec mode in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
4k) The SS switches the downlink codec mode to 8.85 kbit/s and waits for 0.5s.
4l) The downlink radio environment is altered so that the carrier to interference ratio is increased to Thr2u + 4dB – CI_NORM_AFS_DARP_20dB. The SS increments the counter for ‘C/I increases above thresholds’.
4m) The SS checks the CMR received by the MS 200ms after the carrier to interference has been altered. If the CMR indicates that the MS recommends to use 12.65 kbit/s in the downlink, then the SS should increment the successful C/I increase event counter. Otherwise, the SS should increment the unsuccessful C/I increase event counter.
4n) The SS switches the downlink codec mode to 12.65 kbit/s and waits for 0.5s.
4o) The SS repeats steps 4c) to 4n) until 500 samples of C/I increases and 500 samples of C/I decreases have been recorded.
NOTE: The core specifications state that an MS shall respond to a change of C/I within 200ms. The core specifications place no bounds on magnitude or rate of change of C/I. For this test the magnitude of change is bounded by THRESH and HYST selection, and the rate of change is bounded by the 500ms wait periods. These bounds are selected to ensure an MS implementation is not adversely biased by this test.
Maximum/Minimum Duration of Test
Maximum/minimum: 54 minutes.
14.10.9.5 Test requirements
The requirement and minimum set of samples shall not exceed the values given in the following table for each set of thresholds.
Event |
Maximum allowed error rate |
Minimum No. of samples |
C/I increases over Thresholds |
11% |
2000 |
C/I decreases below Thresholds |
11% |
2000 |
NOTE: The maximum allowed error rates for the C/I thresholds are derived from the average of the C/I event counters in Step 1 to Step 4 of the method of test.