I am trying to research the full signal specs for the Motorola Project (P) 25 "Astro" public safety trunk radio transceivers. This is the US version of TETRA.
As far as I can find out, for phase 2, the carrier is 800MHz with C4FM at 2.88KHz and a channel bandwidth of 6.25KHz.
Can anyone confirm this or provide more complete information of the makeup of this signal?
Bob Fraser
The document is one of those damn things you have to buy. I understand charging money in the dark ages when somebody actually had to print the documents, but paying for PDFs is annoying.
You would probably do better putting a post on radioreference.com
Incidentally, I don't believe P25 is tetra.
IIRC TETRA uses Pi/4 DQPSK with 4 timeslots per channel. The iDEN is US system conceptually similar to TETRA. Physical layer of both systems is based on that of DAMPS.
VLV
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