Re: [Discuss-gnuradio] 64MHz USRP Oscillator

[Dan Halperin]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Jul 31, 2008, at 12:15 PM, Wireless Monster wrote:
> All,
> I've been trying to set both Tx and Rx to the same frequency and  
> sending a sinusoid to try to measure the frequency offset, but it  
> does not seem to work... it looks like as both Tx and Rx are driven  
> by the same clock, the frequency the offset gets compensated on the  
> Rx signal so it can not be measured... (???)
>
> Anyone has any clue on how to measure it dynamically at the code  
> startup?


You have to measure frequency offset between different crystals --  
e.g., 2 USRPs. There's no way to calculate an absolute. Maybe if you  
have the RFX version where each DB has (and uses) its own crystal you  
could do this between two DBs on the USRP, but this would still only  
be their relative offsets.

- -Dan
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.8 (Darwin)

iEYEARECAAYFAkiSEOcACgkQy9GYuuMoUJ6nhQCgoOXeqTykV1sj8ClohR/1jjdV
IJYAn1XG433cA2mXEfrGFeA/hcxS3o6h
=n9M9
-----END PGP SIGNATURE-----