14.2.25 Reference sensitivity – Repeated FACCH/F

3GPP51.010-1Mobile Station (MS) conformance specificationPart 1: Conformance specificationTS

14.2.25.1 Definition

The reference sensitivity for control channels is the signal level at the MS receiver input at which a certain FER must be achieved.

14.2.25.2 Conformance requirement.

For Repeated Downlink FACCH and Repeated SACCH (see 3GPP TS 44.006), the minimum input signal level for which the reference performance shall be met is specified in table 1i, according to the propagation condition and type of equipment. The performance requirements for GSM 400 and GSM 700 systems are as for GSM 900 in table 1i, except that the GSM 400 MS speed is doubled from that of GSM 900, e.g. TU50 becomes TU100, and the GSM 700 MS speed is increased by a factor of 1.2, e.g. TU50 becomes TU60.

3GPP TS 45.005 subclause 6.2.

The reference performance for Repeated Downlink FACCH and Repeated SACCH shall be FER £ 5%.

3GPP TS 45.005 subclause 6.2.

When calculating FER, a FACCH frame and its repetition or a SACCH frame and its repetition respectively, shall be counted as one frame and a frame erasure shall be counted when neither the FACCH frame nor its repetition or neither the SACCH frame nor its repetition respectively, could be successfully decoded.

3GPP TS 45.005 subclause 6.2.

The reference performance levels for Repeated Downlink FACCH and Repeated SACCH shall be corrected according to the values in the table below, describing the reference performance level correction factors for packet switched channels:

	MS, GMSK modulated signals
‑	for DCS 1 800 class 1 or class 2 MS	+2/+4 dB**
‑	for DCS 1 800 class 3 MS	+2 dB
‑	for GSM 400 small MS, GSM 900 small MS GSM 850 small MS and GSM 700 small MS	+2 dB
‑	for other GSM 400, GSM 900 MS and GSM 850 MS and GSM 700 MS	0 dB
	for PCS 1900 class 1 or class 2 MS	+2 dB
	for other PCS 1900 MS	0 dB

** For DCS 1 800 class 1 and class 2 MS, a correction offset of +2dB shall apply for the reference sensitivity performance as specified in table 1a for the normal conditions defined in Annex D and an offset of +4 dB shall be used to determine all other MS performances.

3GPP TS 45.005 subclause 6.2

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.

14.2.25.3 Test purpose.

To verify that the MS does not exceed the conformance requirement under TUhigh propagation condition with an allowance for the statistical significance of the test.

14.2.25.4 Method of test

14.2.25.4.1 Initial conditions

A call is set up according to the generic call set up procedure on a TCH/F with an ARFCN in the Low ARFCN range, power control level set to maximum power.

The SS shall use Repeated FACCH for command and response frames for the duration of the test.

Each pair of FACCHs are counted as a single sample.

The SS transmits Standard Test Signal C1 on the traffic channel.

14.2.25.4.2 Procedure

a) The fading function is set to TUhigh.

b) The SS sets the amplitude of the wanted signal to –104dBm + Corr, (where Corr is the correction factor from the table above)

c) The SS sends a Layer 3 message which does not require a Layer 3 response from the MS. Due to the low signal level the MS may not be able to acknowledge an RR frame and the L2 entity of the SS will repeat the Layer 2 frame. Each retransmitted L2 frame will be counted and will indicate a frame erasure event.

d) The SS determines the frame erasure events during at least the minimum number of samples of FACCH/F frames.

NOTE: These frames will not be consecutive but it is expected that the statistical significance of the tests will not be unduly degraded.

Maximum/Minimum Duration of Test

Maximum: 12 minutes.

Minimum: 10 minutes (GSM700, GSM850, GSM900), 5 minutes (DCS1800, PCS900)

14.2.25.5 Test Requirements

The error rates measured shall not exceed the test limit error rate values given in table 14.2.25-2.

For more information on statistical testing of FER performance, especially the definitions of limit lines refer to Annex A7.

Table 14.2.25-1: Minimum test times due to TU high fading conditions

Full Rate 50 km/h
Frequency	0,7	0,85	0,9	1,8	1,9	GHz
Wavelength	–	0,35	0,33	0,17	0,16	m
min test time	–	604	570	285	270	s
	–	00:10:04	00:09:30	00:04:45	00:04:30	hh:mm:ss
Full Rate 60 km/h
Frequency	0,7	0,85	0,9	1,8	1,9	GHz
Wavelength	0,43	–	–	–	–	m
min test time	611	–	–	–	–	s
	00:10:11	–	–	–	–	hh:mm:ss

NOTE: Minimum test time calculation due to fading is based on the best rate 50/3 frame relation in table 14.2.25-3

Table 14.2.25-2: Test Limits for Repeated FACCH/F sensitivity

Channel	Type of measurement	Propagation condition	Original FER requirement	Derived test limit %	Target number of samples
FACCH/F	FER	TUhigh/No FH	5,00	6,17	5592

Table 14.2.25-3: Maximum test times

Maximum test time (best rate 50/3 per second) (s)	Maximum test time (best rate 50/3 per second) (hh:mm:ss)	Maximum test time (worst rate 50/6 per second) (s)	Maximum test time (worst rate 50/6 per second) (hh:mm:ss)
336	00:05:36	671	00:11:11