20.9 Running average of the surrounding cell BCCH carrier signal levels

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

20.9.1 Definition


20.9.2 Conformance requirement

1. Whilst in idle mode an MS shall continue to monitor all BCCH carriers as indicated by the BCCH allocation (BA – See table 1). A running average of received signal level (RLA_C) in the preceding 5 to:

– Max. {5, ((5  N + 6) DIV 7) * BS_PA_MFRMS / 4};

seconds shall be maintained for each carrier in the BCCH allocation. N is the number of non-serving cell BCCH carriers in BA and the parameter BS_PA_MFRMS is defined in 3GPP TS 45.002; 3GPP TS 45.008, subclause 6.6.1.

2. The same number of measurement samples shall be taken for all non-serving cell BCCH carriers of the BA list, and the samples allocated to each carrier shall as far as possible be uniformly distributed over each evaluation period. 3GPP TS 05.08 / 3GPP TS 45.008, subclause 6.6.1

20.9.3 Test purpose

1. To verify that if the MS calculates a received level average (over 5 s) for a non-serving suitable cell which results in the value of C2 exceeding the value of C2 for the serving cell, then cell reselection takes place to the non-serving cell.

2. To verify that by using suitable varying levels of signal strength for non serving cells, the MS samples on non serving cell BCCH carriers are as far as possible distributed uniformly over each evaluation period.

20.9.4 Method of test Initial conditions

Parameters changed from Default values table 20.1.


Carrier 1

Carrier 2

Carrier 3

Carrier 4

Carrier 5

Carrier 6

RF Signal Level

(dBV emf() / dBm)

53 / -60

33 / -80





RXLEV_ACCESS_MIN (dBV emf() / dBm)

23 / -90

23 / -90







BS_PA_MFRMS is set to 4 for this test.

The BA(BCCH) list only contains 7 ARFCNs including the ARFCNs of the carriers used during the test.

NOTE: With 7 ARFCNs in the BA(BCCH) list and BS_PA_MFRMS=4 the MS will maintain a running average on surrounding cells over a period of 5 s. Procedure

a) The SS activates the carriers. The MS is not paged on carrier 1. The SS monitors carriers 1 and 2.

b) The MS is switched on.

c) The SS starts switching the level of carrier 2 between -80 dBm and -57 dBm every 2,7 s and continues to do so until the end of the test.

d) The SS decreases the level of carrier 1 to -76 dBm.

NOTE: As a result of the switching in levels, the running average on carrier 2 will be between -66 dBm and ‑71dBm, assuming that samples are distributed over five consecutive paging blocks.

20.9.5 Test requirements

1) After step b), there shall be no access from the MS on carrier 1 or carrier 2, within 50 s.

2) After step c), there shall be no access from the MS on carrier 1 or 2 within 25 s.

NOTE: Any potential access on is likely to occur within 20 s.

3) After step d), the MS shall access on carrier 2 within 20 s.