P25 TDMA CC

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MotoBill

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I am looking for anyone that works with, or who may reside in or near a P25 system using the TDMA CC to make a short (15-30 seconds) raw symbols capture of the control channel. The symbols captures can be make with the current boatbod version of op25, or in the form of an IQ dump using the recording function of FMP24 or FMPA used with DSDPlus FL.

Thanks!

Bill
 

sarguy1941

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Control channel is FDMA in a TDMA system at least with MSI.
 

triptolemus

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Control channel is FDMA in a TDMA system at least with MSI.

The future is now, old man! :) P25 TDMA CC is in the TIA standards, fyi.

See this thread for the discussion and why OP is asking.

 

RFI-EMI-GUY

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I had looked into this last year with respect to /\/\. The intent was to simultaneously process two streams of control channel traffic to overcome the uplink capacity limitation of Slotted Aloha. When one slot saturates, subsequent requests go through the second slot. /\/\ was not intending to put voice traffic on the second slot. So Intellirepeater operation is no longer supported. I have to wonder how Uniden intends to deal with this for their scanners.
 
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MotoBill

MotoBill

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The future is now, old man! :) P25 TDMA CC is in the TIA standards, fyi.

See this thread for the discussion and why OP is asking.


I have been following this thread and have a copy of TIA-102.BBAD to work from. I am also aware that Max is working independently on this using .wav file captures provided by someone that's a part of that discussion thread.

What I am hoping to accomplish is to find someone that can make an IQ capture file using FMP24 or FMPA (depending on the SDR) and provided that said party already has DSDPlus FL. The .IQ files from DSDPlus FL can be converted directly to op25 symbols with a higher degree of accuracy than having to deal with .wav files with the end goal to obtain enough TDMA CC symbols for testing and code development.
 
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