Dear all,
I tried to achieve burst transmission on usrp X310, the brief tx flowgraph in gnuradio is in the below:
message_burst_source -> signal processing blocks --> usrp_sink
New message will be inserted into the message queue of message_burst_source.
Since message_burst_source will attach SOB and EOB tag to the data stream, usrp will know the start and end of each burst. After reading 'Busrt Transmission' section in this link:
https://gnuradio.org/doc/doxygen/classgr_1_1uhd_1_1usrp__sink.html, my understanding is that because of these two tags, even the two message arrives at usrp at a different time, usrp will not complain about underrun. However, according to results from my experiments, as the time difference between two contiguous message increases, underflow will show up and become more and more severe. For a real burst transmission, time gap between two message should be expected. Therefore, I feel confused about the using of SOB and EOB tags here. Can they help to remove "underrun" under burst transmission? If not, is there any other methods that can make burst transmission with usrp possible without triggering underrun?
Thanks a lot for your help,
Yang