Re: [Discuss-gnuradio] Tetra receiver

[Grzegorz Suder]

Actualy what I am worrying about are discontinuous TDMA signals (for example: receiving specific time slot). I guess that capturing such TDMA signal (Tetra is just an example due to 4 time slots) where only one slot is transmitting may require synchronization to external time source.

On Wed, Jan 21, 2009 at 7:59 PM, Eric Blossom <address@hidden> wrote:

On Mon, Jan 19, 2009 at 10:56:13AM +0100, Grzegorz wrote:
> Hello,
> I've looked through Wiki and discussion archives but I haven't found answer
> for my question. Is there any working code for Gnu Radio that is able to
> receive Tetra subscriber (not base station) signal and convert it into
> bitstream? I believe that demodulation is already done (DQPSK as I know) but
> there is still timing and slot separation issue. Seems that there were
> attempts to introduce support for inband signaling for Gnu Radio but last
> information I've found are from 2007.
> Regards,

I don't know of anybody who's done this, but it should be possible.
(There's not much (any?) Tetra in the US, so those of us in the US
haven't spent any time on it.)  If you're doing receive only, you
don't need the inband features.  Just grab all of the signal and sort
out the framing structure on the host.

Eric