[Discuss-gnuradio] High LO leakage in xcvr 2450 with new UHD?

[Apurv Bhartia]

Hi All - 

I've been using the new UHD driver (003.004.002) stable release w/ XCVR boards on the USRP N200. 

I'm using the xcvr as a transceiver - it receives a packet, then waits a while before sending a packet. However, I can see some spikes in the preamble detection stage which seemingly correspond to the time around which the packet is transmitted. I know XCVR is not full duplex, so I'm *guessing* it's some kind of LO leakage, perhaps? 

On replacing the UHD driver with an old one (003.004.000), the issue seems to have disappeared. 

Any ideas? Attached is a snapshot which shows the smaller spikes (corresponding to tx) next to the bigger ones (corresponds to the rx).

Thanks,
Apurv

new-uhd.png
Description: PNG image