On Thu, Apr 5, 2012 at 9:33 AM, senthil murugan
<
address@hidden> wrote:
> Hi all,
>
> I have some doubt on the time domain view of bpsk signal generated in
> Gnuradio and usrp. I used psk mod block in GRC (sps =2) and created bpsk
> (baseband )waveform with vector source producing 0,1,1 continuously.
>
> When I plotted the output of psk mod block using scope sink, I seen waveform
> of constant 1 for some samples (for 0) , inverted root-raised cosine
> waveform (for 1) and another inverted root-raised cosine waveform (for 1).
> This is repeated continuously and i understand that it because of transmit
> pulse shaping.
>
> Now, the question is when I give this signal to USRP for transmission, how
> the time-domain view of that waveform look like? Will it look like sinusoid
> signal with 180deg phase shift as we all seen in stand. communication text
> books? I guess it will not the case. I tried multiplying the baseband
> waveform with signal source (complex) -- mathematical equivalent of what
> happening in usrp -- and seen waveform. No smooth shift of 180deg.
>
> If anyone having usrp and digital oscilloscope, could you please send me the
> pic of time domain view of output of usrp?
>
> Thanks
> Senthil