Re: [Discuss-gnuradio] a question about benchmark_rx.py and benchmark_tx.py

[Stefan Brüns]

On Thursday 09 October 2008 19:47:10 Bill Stevenson wrote:
> Hello, everyone!
>
> I am just running a demo program to realize communication between two usrps
> using benchmark_rx and benchmark_py under the Python/digital dir. But when
> I am trying to use dqpsk modulation scheme, the packets received are
> totally wrong. What's wrong with the programs? I am really confused. Could
> anybody give me a hint or help me out? Thank you!!!
>
> Bill

I had a problem with different oscillator frequencies on two boards, not much 
but enough for the digital pll in the receiving gnuradio block to lose 
tracking.

As a workaround, I used the usrp_fft.py programm as a receiver, and on the 
sending side just a carrier. This way, I could determine the frequency offset 
between the two boards.

Stefan

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