Re: [Discuss-gnuradio] Question about potential application of gnuradio and the USRP

[Matt Ettus]

Quoting Heiko Jones <address@hidden>:

> I have a potential application that I want to try with gnuradio and
> eventually the USRP. I have a digital data stream, already down
> converted here in the lab (I can worry about the real RF signal later),
> that is a 0 to 5V level PCM data stream, usually encoded NRZ-L, but
> possible NRZ-M or Biphase-L. Additionally, it can be Viterbi encoded or
> not. The stream of ones and zeros can be up to 1.92 Mbits/sec. First,
> can the USRP read a signal like that and give me a bit stream out to my
> application with the simple raw coax daughter card? I would also like
> to, at the same time, read in a similar data stream of IRIG-B time (sine
> wave, amplitude change makes marks and spaces of slo code) that is
> 1Kbit/sec.

This would be a good application of the USRP.  The auxiliary digital IO will
come in handy for the IRIG-B part.

> Also, potentially, since the digital data stream is actually in frames
> with a frame sync pattern in it, is there room for the USRP to actually
> digitize and frame sync it for me in the fpga, and send the binary data
> already in frames to my application too? Same question for converting
> IRIG stream into a digital time in the fpga.

There is quite a bit of room left in the FPGA if you do not need to use all 4 in
and out channels.  I think you could do this in the FPGA without too much
trouble.

Matt