Re: [Discuss-gnuradio] GRC pure FSK with USRP1 board sampling troubles

[LRK]

On Thu, May 19, 2011 at 03:34:09PM -0700, justynnuff wrote:
> 
> Nick Foster-4 wrote:
> > 
> > I think your transmit side is fine. The .wav source should be
> > unthrottled. The receive side is where you're going to run into trouble.
> 
> Indeed you're right.  Upon further research, I realised that nothing
> throttles the Tx side but the USRP.  So, according to my previous math, all
> I need is 128Msam/sec / interpolation > 2.8MHz.

Am I missing something here? The "transmitter" should be a source and
multiplier to get the carrier frequency to the USRP and throttled by
the USRP sink. There should be no underruns. The audio file should
be throttled to it's bit rate and used to modulate the "carrier". Thus
the modulation bit rate should be recovered at the demodulator in the
receiver and right to feed a soundcard. The two-clock problem should
only be between the soundcards. If there is a audio source rather than
a file, it should throttle the modulation at it's own rate.


-- 
LRK
gr-user . ovillatx.sytes.net