3GPP44.018GSM/EDGE Radio Resource Control (RRC) protocolMobile radio interface Layer 3 specificationRelease 16TS
This message is sent on the CSCH, which is one of the broadcast channels (ref. 3GPP TS 45.002). Its purpose is to support the synchronization of a COMPACT mobile station to a BSS. It does not follow the basic format. Its length is 25 bits. The order of bit transmission is defined in 3GPP TS 44.004. See figure 9.1.30b.1 and table 9.1.30b.1.
Message type: COMPACT SYNCHRONIZATION CHANNEL INFORMATION
Direction: network to mobile station
Figure 9.1.30b.1: COMPACT Frame synchronization information element
Table 9.1.30b.1: COMPACT Synchronization channel information message contents
BSIC, the base station identity code of the base station
R1 and R2, the 2 parts of the reduced TDMA frame number (RFN) as specified in 3GPP TS 45.002.
TG, the time group as specified in 3GPP TS 45.002.