RE: Proper use of stream, on a re-occuring event

Thanks for the reply, I’ll join the USRP-users mailing list.

 

From: Marcus D Leech <patchvonbraun@gmail.com>
Sent: Tuesday, May 19, 2020 12:36 PM
To: Begaye, Alvin A <Alvin.Begaye@gd-ms.com>
Cc: discuss-gnuradio@gnu.org
Subject: Re: Proper use of stream, on a re-occuring event

 

External E-mail --- CAUTION: This email originated from outside GDMS. Do not click links or open attachments unless you recognize the sender and know the content is safe.

 Your approach isn’t horrible. I’d stick with it. 

 

Give that the USRP is sampling at a rate much faster than the transition event you’re describing, I’m wondering if perhaps you don’t really understand how a high-speed sampled baseband signal “works”. Your “can the USRP handle this” comment suggests confusion. 

 

Also as a matter of housekeeping your question is more properly directed to the USRP-users mailing list, not discuss-gnuradio. 

 

 

Sent from my iPhone

On May 19, 2020, at 1:03 PM, "Alvin.Begaye@gd-ms.com" <Alvin.Begaye@gd-ms.com> wrote:



I need to be able to grab a couple of samples at  after some time after a recurring event (step 2e below).   The current method seems to work at the moment, but was wondering if there was a better way.  I tried to read the documentation and example of proper use for this scenario, but I still don’t understand L

 

Also,   the time we need to read the samples is less than a millisecond,   can the USRP handle a transition of  a signal that dropped 20dB that fast?  How long would we have to wait after the power drop?

 

Current method:

1.       stream_cmd.stream_now = true

 

2.       while FOREVER

 

a.       Wait for re-occurring Event

 

b.       Wait for X amount of time

 

c.       stream_cmd.stream_mode = UHD_STREAM_MODE_START_CONTINUOUS;

d.       uhd_rx_streamer_issue_stream_cmd(rx_streamer, &stream_cmd)

 

e.       uhd_rx_streamer_recv(....)

 

f.        stream_cmd.stream_mode = UHD_STREAM_MODE_STOP_CONTINUOUS;

g.       uhd_rx_streamer_issue_stream_cmd(rx_streamer, &stream_cmd);

 

h.       Process Samples

 

  endwhile