Hi Ari,
On 17.12.2012 10:37, Ari Kaspari wrote:
In your Picture http://tetra.osmocom.org/trac/graphviz/caf863214dab2ac9e1beead8b122318020ecb... it seems to me, that I only need PCM Samples from my radioscanner. Thus I think i can stream the discriminator output via soundcard (PCM-Samples) into a linux pipe and use this pipe for your omso-tetra tool.
Is this possible? Or is my radioscanner not possible to "stream" the correct channel pattern?
No, i don't think so. Your radio scanner does FM demodulation. But the TETRA signal is modulated with Pi/4-DQPSK (or QAM - not supported by osmocom-tetra). So the real information is already lost, when it comes out of the discriminator output.
The FUNcube Dongle (linked schematics) does no demodulation. It just digitise the I/Q-Data and puts it in the left/right channel of the PCM stream.
Greetings Felix