Hi, I was trying to implement a TDD system using UHD time stamp feature. I used the UHD API directly (not gr_uhd) to test it first. The transmit path sends bursts periodically, and the receive path captures all the time. For comparison, I have also recorded the signal from another USRP N200 receiver. The first problem I observed was that few bursts following the FIRST burst are always lost. Pictures below are snapshots of received signals by the receive path (a) and the separate receiver (b) (a)[image: Inline image 2].
[image: Inline image 3]
(b)
The second problem is that the receive path does not capture the
transmitted signal (c) unless
the USRP box is power restarted. Flushing the receive buffer with the
following command
did not fix the problem.
...
while(true) {
num_smpls = rx_stream->recv(buffs,
rx_spp,
md);
if (md.error_code == uhd::rx_metadata_t::ERROR_CODE_TIMEOUT)
break;
}
...
[image: Inline image 4]
Your help would be appreciated.
Best Regards!
Beyene
<<image.png>>
<<image.png>>
<<image.png>>
_______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
