Question asked: why does the number of data packets in OFDM system decrease?

[maolin liu]

Hi,

I asked this question before, about the problem of packet sending on gr-digital/example/ofdm/tx_ofdm.grc and rx_ofdm.grc, I successfully solved the problem of too many packets leading to packet missing, I added 10 zeros after each packet to avoid missing detection, as shown in my attachment.

But now I have a new problem, as shown in my flowchart, I created a new OOT module, this module has 24 pictures of data, I will send the data of these 24 pictures at intervals of ten seconds in turn (using time.sleep(10)) statement, I have the corresponding sink to process this data, I will replace the USRP source and sink with ZMQ PUB Sink and source My program runs normally, But the problem occurs when the USRP is sent, and after I check it, I found that in addition to the first (that is, the data information of the first picture) can be successfully received without reduction, after an interval of ten seconds, the information of the second picture begins to be transmitted (the information of the first picture only takes about 1 second to be transmitted, so there is a waiting time of 9 seconds), but the receiving end receives a few packets less. I'm not quite sure why, I checked the data entered into the USRP Source before and they were accurate, so I thought that the loss of the data occurred in subsequent transfers, but the cause could not be found. Forgot to say that my terminal has the prompt "U", I don't know if this is the cause, since it seems to be just a underflow warning

If there are enthusiastic people who are interested in this, we can have a detailed discussion, because the length is too short, I can not say too detailed, I can show my code later, thank you in advance.

Best regards,

linge

vedio_tx.pdf
Description: vedio_tx.pdf

video_rx.pdf
Description: video_rx.pdf