Re: [Discuss-gnuradio] gr-usrp library

[Eric Blossom]

On Sun, Apr 16, 2006 at 09:38:42PM -0700, Ges wrote:
> Hi Eric,

>  I am facing a weird problem.
>  
>  I was trying the rx.py and tx.py gmsk scripts in
>  gnuradio-examples/python/gmsk - this is the old gmsk
>  implementation. I am getting the character stream I sent using
>  tx.py at the receive side. But if I disable the gui (using the
>  --no-gui option), then I do not get any output.

Gesley,

There's a reason that the code you are trying to make work is no
longer in the distribution.  It didn't work well.  It has been
replaced by the gmsk2 code and examples.

>  I couldnt find any reason for why this is happening. I thought that
>  maybe its because of some kind of a time delay. So, I ran rx.py
>  first and then tx.py, but if the --no-gui option is used I do not
>  get anything in the file_sink at the rx side.

>  Any ideas as to why this is happening?

Have you plotted the raw data you are receiving from the USRP, perhaps
in octave?  What are the maximum and minimum values of both the real
and imaginary components?  If you're not getting anything in the file,
perhaps the correlator is never seeing the synchronization pattern.
Have you instrumented the correlator?

Eric