7.1 Static Layer 1 receiver functions (nominal error ratios)
3GPP51.021Base Station System (BSS) equipment specificationRadio aspectsRelease 17TS
7.1.1 Test Purpose
The static Layer 1 receiver functions verified in these tests are the RF parts, the multiplexing and multiple access functions, any existing equalizer, the deciphering functions, the de‑interleaving and the channel decoding on the receive side. The performance of the receiver at the maximum specified input level is also verified.
Nominal error ratios (Bit Error Ratio ‑ BER) are measured at a logical reference point that represents the performance before channel decoding. This measurement can be performed for TCH/FS, using unprotected class II bits extracted after channel decoding, but before any extrapolation. Therefore, the results obtained are representative of the logical reference point before channel decoding. The test can also be performed on the uncoded bits extracted before any channel decoding of a PDTCH channel.
If the BTS supports SFH, this test also verifies the TCH/FS performance in frequency hopping under interference conditions. In this case, the Frame Erasure Ratio (FER) for TCH/FS is used as the performance criteria.
The Random access performance at high input levels is verified by measuring the Frame Erasure Ratio for RACH.
7.1.2 Test Case
GMSK modulation
1) For BER measurements, if Slow Frequency Hopping (SFH) is supported by the BSS, the BSS shall be hopping over the maximum range and number of ARFCNs possible for the test environment and which are available in the BSS configuration. If SFH is not supported, the test shall be performed for the radio frequency channels B, M and T. In both cases the tests shall be repeated until all the RF equipment in the BSS configuration is tested on all specified carrier frequencies.
If test is performed with TCH/FS a test signal with normal TCH/FS modulation originating from the BSSTE shall be applied to the BSS receiver input. The unprotected class II bits obtained from the BSS receiver after channel decoding and before any extrapolation shall be compared with the unprotected class II bits originating from the BSSTE.
If test is not performed with TCH/FS a test signal with normal PDTCH modulation originating from the BSSTE shall be applied to the BSS receiver input. The uncoded data bits obtained from the BSS receiver shall be compared with the bits originating from the BSSTE.
NOTE: Uncoded data bits refer to the encrypted bits of a burst, extracted by the receiver without any signal processing improvement from encoding/decoding of the signal.
The test shall be performed at the following power levels of test signal:
a) A lower limit (20 dB above the reference sensitivity level of the BSS under test), as specified in table 7.1-1, for static propagation conditions.
b) ‑40 dBm, for static propagation conditions.
c) ‑15 dBm for GSM 400, GSM 700, GSM 900, ER-GSM 900, GSM 850 and MXM 850 BTS, and -23 dBm for DCS 1800, PCS 1900 and MXM 1900, for static propagation conditions only.
d) -18 dBm, -14 dBm and -9 dBm for Wide Area, Medium Range and Local Area multicarrier BTS equipped with multicarrier receiver, respectively. The levels apply for the bands GSM 400, T-GSM 810, GSM 850 and E-GSM 900, for static propagation conditions only.
e) -23 dBm, -19 dBm and -14 dBm for Wide Area, Medium Range and Local Area multicarrier BTS equipped with multicarrier receiver, respectively. The levels apply for the bands DCS 1800 and PCS 1900, for static propagation conditions only.
f) -5 dBm for GSM 900, ER-GSM 900, GSM 700, GSM 850 and MXM 850 pico-BTS and -14 dBm for DCS 1800, PCS 1900 and MXM 1900 pico-BTS, for static propagation conditions only.
g) A lower limit (20 dB above the reference sensitivity level of the BSS under test), as specified in table 7.1-1, for EQ50 propagation conditions, except for GSM 400 where EQ100 applies and for GSM 700 where EQ60 applies, step g) does not apply to pico-BTS and Local Area multicarrier BTS.
h) -40dBm, for EQ50 propagation conditions, except for GSM 400 where EQ100 applies and for GSM 700 where EQ60 applies, step h) does not apply to pico-BTS and Local Area multicarrier BTS.
2) For RACH, the test shall be performed for the radio frequency channels B, M and T. A test signal consisting of RACH bursts originating from the BSSTE shall be applied to the BSS receiver input. The proportion of RACH bursts at the input to the receiver which are not correctly identified by the BSS shall be measured.
The test shall be performed at the following power levels of test signal:
a) A lower limit (20 dB above the reference sensitivity level of the BSS under test), as specified in table 7.1-1, for static propagation conditions.
b) ‑40 dBm, for static propagation conditions.
c) ‑15 dBm for GSM 400, GSM 700, GSM 900, ER-GSM 900, GSM 850 and MXM 850BTS and -23 dBm for DCS 1800, PCS 1900 and MXM 1900 for static propagation conditions.
d) -16 dBm, -12 dBm and -7 dBm for Wide Area, Medium Range and Local Area multicarrier BTS equipped with multicarrier receiver, respectively. The levels apply for the bands GSM 400, T-GSM 810, GSM 850 and E-GSM 900, for static propagation conditions only.
e) -23 dBm, -19 dBm and -14 dBm for Wide Area, Medium Range and Local Area multicarrier BTS equipped with multicarrier receiver, respectively. The levels apply for the bands DCS 1800 and PCS 1900, for static propagation conditions only.
2a) For BSS supporting EC-GSM-IoT the test shall be performed for the radio frequency channel M. A test signal consisting of EC-RACH bursts according to the supported TS option(s) as stated below and originating from the BSSTE shall be connected to each of the two RX antenna connectors via a powersplitting network. The proportion of EC-RACH bursts at the input to the receiver which are not correctly identified by the BSS shall be measured.
The test shall be performed for the following cases:
a) With input signal at a lower limit power level (20 dB above the input signal level at reference performance for EC-RACH CC1 of the BSS under test) as specified in table 7.1-2 for GMSK input signals, using 1 TS EC-RACH on TN1 for static propagation conditions without any blind physical layer transmissions (CC1).
b) With input signal at a power level of
‑15 dBm for GSM 850 and E-GSM 900
– normal BTS and
– multicarrier BTS that are not equipped with multicarrier receiver,
-16 dBm for GSM 850 and E-GSM 900 Wide Area multicarrier BTS equipped with multicarrier receiver,
-12 dBm for GSM 850 and E-GSM 900 Medium Range multicarrier BTS equipped with multicarrier receiver,
-7 dBm for GSM 850 and E-GSM 900 Local Area multicarrier BTS equipped with multicarrier receiver,
‑23 dBm for DCS 1800 and PCS 1900
– normal BTS and
– multicarrier BTS that are not equipped with multicarrier receiver and
– Wide Area multicarrier BTS equipped with multicarrier receiver,
‑19 dBm for DCS 1800 and PCS 1900 Medium Range multicarrier BTS equipped with multicarrier receiver, and
‑14 dBm for DCS 1800 and PCS 1900 Local Area multicarrier BTS equipped with multicarrier receiver,
using 1TS EC-RACH CC1 on TN1, for static propagation conditions.
3) For TCH/FS FER measurements in frequency hopping under interference conditions, two signals are connected to the BSS receiver input via a combining network. The wanted signal with an RF level given in table 7.1-1 shall be cyclically frequency hopping on four carrier frequencies under static conditions. The interfering signal shall be a random continuous, GMSK-modulated signal on only one of the carriers at a level 10 dB higher than the wanted signal.
The test shall be performed with the hopping frequencies centered around RF channel M.
8-PSK, QPSK, 16-QAM and 32-QAM modulations
1) If Slow Frequency Hopping (SFH) is supported by the BSS, the BSS shall be hopping over the maximum range and number of ARFCNs possible for the test environment and which are available in the BSS configuration. If SFH is not supported, the test shall be performed for the radio frequency channels B, M and T. In either case the tests shall be repeated until all the RF equipment in the BSS configuration is tested on all specified carrier frequencies.
A test signal with normal PDTCH modulation originating from the BSSTE shall be applied to the BSS receiver input. The uncoded data bits obtained from the BSS receiver shall be compared with the bits originating from the BSSTE.
NOTE: Uncoded data bits refer to the encrypted bits of a burst, extracted by the receiver without any signal processing improvement from encoding/decoding of the signal.
The test shall be performed at the following power levels of test signal:
a) A lower limit level, as specified in table 7.1-1, for static propagation conditions.
b) –40dBm, for static propagation conditions.
c) The maximum limit as specified in table 7.1-1, for static propagation conditions.
d) Step a and b shall be repeated with the frequency of the input 8-PSK and, if supported, QPSK, modulated signal randomly offset, by +-0,1 ppm (except +-0,2 ppm for GSM400), on a burst-by-burst basis. For each burst, the sign of the frequency offset is chosen according to a 511-bit pseudo-random sequence, defined in ITU-T recommendation O.153.
Table 7.1-1: Limit of RF input for testing of Static Layer 1 receiver functions
|
BTS Type |
Lower Limit GMSK, 8-PSK and QPSK |
Maximum Limit 8-PSK and QPSK |
Lower Limit 16-QAM and 32-QAM EGPRS2-A |
Lower Limit 16-QAM and 32-QAM EGPRS2-B |
Maximum Limit 16-QAM and 32-QAM |
|
GSM 400/GSM 850/GSM 900/ER-GSM 900/DCS 1800/PCS 1900/MXM 850/MXM 1900/GSM 700 normal BTS |
‑84 dBm |
-26 dBm |
-84 |
-78 |
-29 |
|
GSM 900/ER-GSM 900/GSM 850/MXM 850/GSM 700 micro‑BTS M1 |
‑77 dBm |
-24 dBm |
-77 |
-71 |
-27 |
|
GSM 900/ER-GSM 900/GSM 850/MXM 850/GSM 700 micro‑BTS M2 |
‑72 dBm |
-19 dBm |
-72 |
-66 |
-22 |
|
GSM 900/ER-GSM 900/GSM 850/MXM 850/GSM 700 micro‑BTS M3 |
‑67 dBm |
-14 dBm |
-67 |
-61 |
-17 |
|
GSM 900/ER-GSM 900/GSM 850/MXM 850/GSM 700 pico‑BTS P1 |
-68 dBm |
-16 dBm |
-68 |
-62 |
-19 |
|
DCS 1800/PCS 1900/ MXM 1900 micro‑BTS M1 |
‑82 dBm |
-24 dBm |
-82 |
-76 |
-27 |
|
DCS 1800/PCS 1900/ MXM 1900 micro‑BTS M2 |
‑77 dBm |
-19 dBm |
-77 |
-71 |
-22 |
|
DCS 1800/PCS 1900/ MXM 1900 micro‑BTS M3 |
‑72 dBm |
-14 dBm |
-72 |
-66 |
-17 |
|
DCS 1800/PCS 1900/ MXM 1900 pico-BTS P1 |
-75 dBm |
-17 dBm |
-75 |
-69 |
-20 |
|
GSM 400/GSM 850/GSM 900/DCS 1800/PCS 1900/GSM 700 Wide Area multicarrier BTS |
‑84 dBm |
-26 dBm |
-84 |
-78 |
-29 |
|
GSM 400/GSM 850/GSM 900/DCS 1800/PCS 1900/GSM 700 Medium Range multicarrier BTS |
‑78 dBm |
-22 dBm |
-78 |
-72 |
-25 |
|
GSM 400/GSM 850/GSM 900/DCS 1800/PCS 1900/GSM 700 Local Area multicarrier BTS |
‑70 dBm |
-17 dBm |
-70 |
-64 |
-20 |
Table 7.1-2: Limit of RF input for testing of Static Layer 1 receiver functions for EC-GSM-IoT
|
BTS Type |
Lower Limit GMSK |
|
GSM 850/E-GSM 900 normal BTS |
-96 dBm |
|
DCS 1800/PCS 1900 normal BTS |
-96,5 dBm |
|
E-GSM 900/ GSM 850 micro‑BTS M1 |
-89 dBm |
|
E-GSM 900/ GSM 850 micro‑BTS M2 |
-84 dBm |
|
E-GSM 900/GSM 850 micro‑BTS M3 |
-79 dBm |
|
E-GSM 900/GSM 850 pico‑BTS P1 |
-80 dBm |
|
DCS 1800/PCS 1900 micro‑BTS M1 |
-94,5 dBm |
|
DCS 1800/PCS 1900 micro‑BTS M2 |
-89,5 dBm |
|
DCS 1800/PCS 1900 micro‑BTS M3 |
-84,5 dBm |
|
DCS 1800/PCS 1900 pico-BTS P1 |
-87,5 dBm |
|
GSM 850/E-GSM 900 |
-96 dBm |
|
DCS 1800/PCS 1900 |
-96,5 dBm |
|
GSM 850/E-GSM 900 Medium Range multicarrier BTS |
-90 dBm |
|
DCS 1800/PCS 1900 Medium Range multicarrier BTS |
-90,5 dBm |
|
GSM 850/E-GSM 900 |
-82 dBm |
|
DCS 1800/PCS 1900 |
-82,5 dBm |
7.1.3 Void
7.1.4 Conformance requirement
Test Environment:
Normal: For GMSK BER measurements, each TRX shall be tested.
For RACH and EC-RACH, if supported, the TRX supporting the BCCH shall be tested.
For 8-PSK, QPSK, 16-QAM and 32-QAM modulation, each TRX shall be tested. Any modulated channel type for each modulation can be used.
Extreme Temperature: For GMSK BER measurements, one TRX shall be tested on one timeslot, for static propagation conditions only.
For RACH, the TRX supporting the BCCH shall be tested.
For TCH/FS FER measurements, the test need not be performed.
For 8-PSK, QPSK, 16-QAM and 32-QAM modulation, one TRX shall be tested on one timeslot, for static propagation conditions only. Any modulated channel type for each modulation can be used.
Vibration: For GMSK BER measurements, one TRX shall be tested on one timeslot, for static propagation conditions only.
For TCH/FS FER measurements in frequency hopping under interference conditions and for RACH, the test need not be performed.
For 8-PSK, QPSK, 16-QAM and 32-QAM modulation, one TRX shall be tested on one timeslot, for static propagation conditions only. Any modulated channel type for each modulation can be used.
For multicarrier BTS with multicarrier receiver the tests above shall be tested for each receiver antenna port.
Minimum Requirement
The bit error ratio of the unprotected bits (TCH/FS, Class II or uncoded PDTCH bits) shall not exceed:
Static propagation conditions BER ≤ 10‑4 For input levels up to ‑40 dBm
Static propagation conditions BER ≤ 10‑3 For input levels > ‑40 dBm
EQ50 (except for GSM400, where EQ100 applies) propagation conditions BER ≤ 3 %
The FER of TCH/FS under interfering conditions shall not exceed 5 %.
The frame erasure ratio of the RACH shall not exceed 0.5%.
The BLER of the EC-RACH shall not exceed 0,5%.
The bit error ratio of uncoded data bits in 8-PSK, QPSK, 16-QAM and 32-QAM channels shall not exceed:
Static propagation conditions (steps a, b and d) BER ≤ 10‑4 for input levels up to -40 dBm.
Static propagation conditions (step c) BER ≤ 10‑3 for input levels > ‑40 dBm.
7.1.5 Requirement Reference
3GPP TS 45.005 subclause 6.1, subclause 6.5 and subclause 6.6.