[Discuss-gnuradio] USRP DBPSK Demod/Mod Issue

[Shae Hurst]

Hello,
 
We are working on our senior design project using gnuradio and USRP N210. We are connecting two USRP's together through a coax cable with a 30 dB attenuator and each USRP is connected to a host computer via a gigabit ethernet connection.
 
Right now we are trying to modulate and demodulate a packet consisting only of "1's and 0's" from a file generated with the gnuradio file sink. We are seeing strange fluctuation at the output of our USRP receiver. We have attached a link to pictures of our GRC blocks and our source code as well as the gr_plot screenshots documenting the received signal.

https://www.dropbox.com/s/r5eob2180dzksf1/USRP_TX_Problem.pdf
 
Thanks,
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