Re: [Discuss-gnuradio] Signal coming from the USRP to the computer

[Marcus D. Leech]

On 05/29/2011 04:50 PM, John Andrews wrote:
> Hi All,
> I want to know what is the signal coming from the USRP onto the USB 
> bus. I know that the received signal is a baseband signal and assuming 
> complex sampling (I have RFX2400 daughterboards) each complex sample 
> that enters the USB bus is the following,
>
> x[i] = (inphase_component) + j (quadrature_component), and
> x[i] = m(t)cos( 2*pi*FREQ_OFFSET*t + PHI ) + jm(t)sin( 
> 2*pi*FREQ_OFFSET*t + PHI ), where m(t), is the actual message signal, 
> FREQ_OFFSET is the frequency offset, and PHI is the phase.
>
> Is that correct?
>
> Thanks
More or less, yes.

There will be random noise components as well, since this is "real 
world", rather than purely a Matlab simulation :-)



--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org