Re: [Discuss-gnuradio] UHD USRP2 full duplex mystery solved

[Marcus D. Leech]

On 14/03/2011 12:12 PM, Marc Epard wrote:
> Although the XCVR2450 doesn't do full duplex, the WBX does, and current UHD 
> avoids the problem I described in my previous message. However, the WBX has 
> enough internal leakage between tx and rx that we gave up on 
> single-daughterboard full duplex. We now use a USRP2 with a WBX for tx and a 
> USRP N210 with a DBSRX2 for rx.
>
> As for examples, I'll try to clean up my C++ app and post it later this week. 
> GRC works fine full-duplex, too, I believe.
>
> -Marc
Saw XCVR2450, and assumed you were using it.

How much isolation does your application need?  The HMC174-series 
switches in the WBX are roughly 26dB isolation each, and there should be 
two such paths
  between transmit and receive when using RX2 and TX/RX, giving roughly 
52dB isolation (at least from the switches--circuit paths may make this 
number worse).