Re: [Discuss-gnuradio] frequency offset of USRP

[Trond Danielsen]

2008/3/30, Sl Peng <address@hidden>:
> Hi all:
>  My task is to use the USRP to down convert the GPS L1 channel to
>  baseband signal.
>  I have some problems with the carrier offset of the DBS_RX
>  daughterboard.
>  When I set f_l0 of the DBS_RX daughterboard to be 1575.42e6 which is the
>  center frequency of GPS L1 signal, I found the real frequency in the
>  tune(double _freq) function was 1575.5e6. So there is 80000 hz offset. I
>  want to know what the output of DBSRX daughterboard is. What is the
>  effect of this offset to my input signal?
>
>  Next, I need to down convert the output signal of the daughterboard. Fox
>  example, I want to down convert it to 1.5M hz. Then, what should I do?
>  I think I should use this function:
>  usrp_standard_rx: set_rx_freq (int channel, double freq).
>
>  What is the input value of freq?
>
>  Any suggestions? Thanks a lot!

Hi,

I think you might find this thread from the mailing list archive
useful: http://lists.gnu.org/archive/html/discuss-gnuradio/2007-04/msg00105.html
-- 
Trond Danielsen