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The forward link consists of up to 64 logical CDMA channels each occupying the same 1228-kHz bandwidth.
The forward link supports four types of channels:
Pilot (channel 0): A continuous signal on a single channel. This channel allows the mobile unit to acquire timing information, provides phase reference for the demodulation process, and provides a means for signal strength comparison for the purpose of handoff determination. The pilot channel consists of all zeros.
Synchronization (channel 32): A 1200-bps channel used by the mobile station to obtain identification information about the cellular system (system time, long code state, protocol revision, etc.).
Paging (channels 1 to 7): Contain messages for one or more mobile stations.
Traffic (channels 8 to 31 and 33 to 63): The forward channel supports 55 traffic channels. The original specification supported data rates of up to 9600 bps. A subsequent revision added a second set of rates up to 14,400 bps.
Fig: Forward link channels: