??????the output of the "USRP Source"?

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My screenshot is in the attachment ,Is there a big difference between the simulated channel of the "channel model" and the actual channel connected via USRP? How can I adjust the parameters or add other modules to recover the original signal?

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??????: "????????" <2127629883@qq.com>;

????????: 2021??5??21??(??????) ????4:23

??????: "discuss-gnuradio"<discuss-gnuradio@gnu.org>;

????: the output of the "USRP Source"?

Hi!

I tried to use the "channel model" module to simulate the interference caused by the channel. I used the "constellation modulator" to output the QPSK signal, and restored the original signal at the receiving end through multiphase clock synchronization, equalizer, etc. The performance was very good, but If I use "USRP Sink" and "USRP source" to send and receive signals, that is to say, the "channel model" becomes the interference of the actual space. When I use the same recovery settings as before, the signal does not recover. what should I do?Below is my GRC. .diagram

Thanks a lot!

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