Synchronization Channel


Synchronization Channel is a downlink only control channel used in GSM cellular telephone systems.
It is part of the Um air interface specification.
The purpose of the SCH is to allow the mobile station to quickly identify a nearby cell and synchronize to that BTS's TDMA structures.
Each radio burst on the SCH contains:
When mobile turns on after getting FCCH it waits for getting SCCH which is to synchronise mobile's oscillator frequency with the frequency of the Base channel.
The burst structure of the SCH is defined in GSM specification 05.03 section 4.7.
The encoding of the frame clock is defined in GSM specification 04.08 section 9.1.30.
The TDMA multiplexing pattern of the SCH is defined in GSM specification 05.02 clause 7 table 3.
The GSM Synchronization Burst Contains a Training Sequence of 64 bits that is used to facilitate synchronization.