Re: [Discuss-gnuradio] Re: Frequency shift in the received and generated signals of the USRP

[Michael L Dickens]

On Nov 20, 2008, at 11:18 AM, Brian Padalino wrote:
> > Also is there some way(GNU Radio code that uses PLL and the frequency
> > offset) to demodulate the signal at this offset frequency back to
> > baseband?
>
> Use the source.  I don't know if there is a block already written that
> will do what you want to do - but the fact that you have insight into
> all the blocks and the ability to write your own algorithms empowers
> you to make GNU Radio do whatever you want it to do.

I've used "gr.freq_xlating_fir_filter_XXX" with success for this  
purpose .. admittedly all by hand.  AFAIK, there is no automated way  
to do it, though IIRC some folks have proposed working on such  
algorithms in the past (search the listserv archives).  For more  
info, look at the source code in gnuradio-core/src/lib/filter . - MLD