Re: [Discuss-gnuradio] The correct way to receive pulses?

[seph 004]

--- Matt Ettus <address@hidden> wrote:

> seph 004 wrote:
> > My question is about the correct setup to receive
> > pulses. I've managed to get my system to transmit
> 1
> > second pulses at 16 ms intervals.
> >
> > I wanted to test how the usrp receives these
> pulses
> > again by routing the output of the basic TX board,
> to
> > the input of the basic RX board. This seems to
> work
> > for continuous wave signals, but when I try to
> route
> > my pulsed output back, the signal appearing on the
> > host pc appears to be saturated. I end up getting
> a
> > series of combs that don't seem to be related to
> the
> > incoming pulse in anyway.
> >
> > The pulses are centred at 40 kHz and have 2 kHz
> bw.
> > I've set the decimation rate to 250, and used the
> > set_freq method to tune to 40 kHz. I know I can
> > receive a 40 kHz wave as I have done so with a
> > modified version of usrp_siggen.
> >
> > Is there something Ive overlooked in terms of the
> > settings I've used?
> >   
> 
> 
> What daughterboard are you using?  Only the LFRX and
> LFTX go down to 40 kHz.
> 
> Matt
> 

Thanks for replying.

I'm using the basic RX daughterboard. I know it's not
supposed to be able to pass such low frequency
signals, but I have used it to successfully receive
signals as low as 40 kHz. Those were continuous waves
though. Now that I'm trying to view pulses centered at
40 kHz, I get the behavior I described previously.

I made a mistake in my first email. My transmitter is
outputting 1 millisecond pulses, not 1 second pulses.

Could the behavior I'm seeing be caused by the PRI I'm
using? I'm not sure what to try next.

Regards

Lance 


      
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