Now I’ve tried communication test a lot of times.
I send a signal like below:
https://picasaweb.google.com/lh/photo/Ntw86qudmxB4Qu07Z1TNvQ?feat=directlink
Then RX shows plot like below:
https://picasaweb.google.com/lh/photo/H9RItzjpfemHy-OR2eQhQg?feat=directlink
Most of time it’s fine.
However, very rarely, RX just shows white noise like below:
https://picasaweb.google.com/lh/photo/jJdZIfm6Fd_mGNwu9QRBYQ?feat=directlink
Every condition has not been changed
I just turn USRP off and on and now I have this problem.