Tetrapol-kit June 2017

tetrapol-kit@brmlab.cz

2 participants
3 discussions

Bit ranking in voice frame
by Xilokar 08 Jan '18

08 Jan '18

Hi, I was wondering how the bit positions in voice frames were found (I am talking of voice_frame.py in rp-celp repo) I can not find the info in PAS 0001-7: Version 1.0.3 (so much for a specification...) I am trying to decode Q & ph for each subframe in order to feed the excitation signal in the filters, but there seems to be some incoherency either with my own received frames (that I was not able to test) or with the voice_tones sample from the transmit repo. Regards, Xilokar

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Re: [Tetrapol-kit] RPCELP codec
by P 16 Jun '17

16 Jun '17

The problem is RP-CELP specification for TETRAPOL is incomplete, even the bit order and meaning in voice frame is unknow. The goal is replace A/D converted in tetrapol radio which we posses and send well defined audio signals and sniff encoded audio on radio data bus. We already did this with analog signals using external audio input a got almost all bits solved, but few are still missing. This technique can be also helpfull to find out where radio does encryption and try to extract the encryption algorithm. We have already some usefull setups and few more informations which are not yet published, but lacking required hardware and time to do this. PJ On Fri, Jun 9, 2017 at 9:21 , Алекс Тереж <alextereg(a)gmail.com> wrote: > Good day Jiří Pinkav,, I wanted to know more about the 32-MHz > signal analyzer for a 34 channel? Why, with such characteristics, > maybe I have not yet fully understood your idea, what is its essence, > maybe I will be able to help you something! > > Best regrets, Alex White > > 2017-06-01 18:32 GMT+03:00 Алекс Тереж > <alextereg(a)gmail.com>: >> Ok, I anderstend you, wath can help you and your comand to create >> a working RP-CELP codec? And wath you meen said about @t least 34 >> channels at 32 MHZ would be required to get the data out of bus) and >> this >> seems to be blocker for now@. Do you have 2 tetrrapol radiostation, >> if yes can you sent to men voice trafic and record you voice talk of >> this station! >> >> With best regards, >> AW >> >> 2017-06-01 18:15 GMT+03:00 Pinky <j-pi(a)seznam.cz>: >>> Hi, >>> >>> RP-CELP codec is not finished, a lot of stuff is still missing to >>> reverse- >>> ingeneer. Implemented is only the first part of codec and even >>> here are >>> missing correct coefficients. >>> >>> We have some hardware but are missing digital signal analyzer (at >>> least 34 >>> channels at 32 MHZ would be required to get the data out of bus) >>> and this >>> seems to be blocker for now. >>> >>> Thanks for interest, if You can imagine anny cooperation with this >>> project, >>> please let us now at tetrapol-kit(a)brmlab.cz >>> >>> With best regards, >>> JP >>> >>> >>> On Thursday, 1 June 2017 16.49.53 CEST Алекс Тереж wrote: >>> > Good day *Jiří Pinkav* >>> > >>> <https://brmlab.cz/gitweb/?p=rp-celp.git;a=search;h=783b8c2e538d7fa7a6651df4 >>> > 4ccf9010055b0ca9;s=Ji%C5%99%C3%AD+Pinkava;st=author>, may name >>> Alex White, i >>> > want asked about use tetrapol-kit, namelly how to use and >>> tersting rp-celp >>> > codec, is it work in uncrypted voice frame? At the moment, I'm >>> good at >>> > accepting, decoding and forming the output stream of frames in >>> 120 bits, >>> > but I can not test the possibility of correct speech processing >>> by the >>> > RPCELP codec even on unencrypted freem voices, because I do not >>> have >>> > TETRAPOL stations yet. >>> > >>> > Best regrets, Alex White >>> >>> >> >

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Re: [Tetrapol-kit] RPCELP codec
by Pinky 01 Jun '17

01 Jun '17

Hi, RP-CELP codec is not finished, a lot of stuff is still missing to reverse- ingeneer. Implemented is only the first part of codec and even here are missing correct coefficients. We have some hardware but are missing digital signal analyzer (at least 34 channels at 32 MHZ would be required to get the data out of bus) and this seems to be blocker for now. Thanks for interest, if You can imagine anny cooperation with this project, please let us now at tetrapol-kit(a)brmlab.cz With best regards, JP On Thursday, 1 June 2017 16.49.53 CEST Алекс Тереж wrote: > Good day *Jiří Pinkav* > <https://brmlab.cz/gitweb/?p=rp-celp.git;a=search;h=783b8c2e538d7fa7a6651df4 > 4ccf9010055b0ca9;s=Ji%C5%99%C3%AD+Pinkava;st=author>, may name Alex White, i > want asked about use tetrapol-kit, namelly how to use and tersting rp-celp > codec, is it work in uncrypted voice frame? At the moment, I'm good at > accepting, decoding and forming the output stream of frames in 120 bits, > but I can not test the possibility of correct speech processing by the > RPCELP codec even on unencrypted freem voices, because I do not have > TETRAPOL stations yet. > > Best regrets, Alex White

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Tetrapol-kit June 2017