[Discuss-gnuradio] selecting the USRP antenna port in GRC

[Francois Quitin]

Dear mailing list,

 

I have a small question:

 

I’m using an USRP-2 with a WBX daughterboard (Gnuradio 3.5.0), and I want to use the RX2 port as the receiver and the TX/RX port as the transmitter. In the GNU Radio companion flowgraph, I enter RX2 in the “antenna”-field for the receiver UHD::USRP source block and TX/RX in the “antenna”-field for the transmitter UHD::USRP sink block.

 

When transmitting, I deliberately provoke underflows at the transmitter side (I transmit packets, and stop transmitting in between). When connecting a scope at the receiver end, I seem to observe that during these underflow periods, the receiver still switches back to the TX/RX port. When transmitting, it switches to the RX2 port. This is despite the fact that I specify that the receiver has to use the RX2 port, which it should use all the time.

 

Any advice on this?

 

 

François Quitin, Ph.D.

 

BAEF Post-doctoral research fellow

Electrical & Computer Engineering Dept.

University of California

Santa Barbara, CA 93106-9560

Phone: +1-805-883-8599

Email: address@hidden

Home: www.ece.ucsb.edu/~fquitin