Field Guide · term

Also known as: voice channel, traffic channel

A voice channel (or traffic channel) is a frequency that a trunked radio system temporarily assigns to carry one call.1 When the call ends, the channel returns to the pool for reuse.

ch 1ch 2ch 3 time → (each call borrows a channel, then frees it)
Voice channels are assigned for the duration of a call, then returned to the shared pool.

How it works

The control channel issues a grant directing a talkgroup to a specific voice channel (and, on TDMA systems, a timeslot). The next call from that group may land on a different voice channel entirely.

Relevance to SDR

GopherTrunk tunes a receiver to the granted voice channel to capture the audio, then returns to await the next assignment — following many calls from one capture.

Sources

  1. Trunked radio system — Wikipedia, on per-call voice (traffic) channel assignment. ↩

See also

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