[Discuss-gnuradio] TDD mode with USRPs in GNU Radio

[Johannes Demel]

Hi all,

I plan to implement a TDD system with GNU Radio and X310s w UBX160s. My 
lab setup is as follows:
- multiple USRPs (start with 2, extend to more)
- each USRP shall use 1 TX and one RX port. Preferably on one 
daughterboard in order to extend it to MIMO later on.

At the moment the receiver runs continuously. While TX bursts happen 
occasionally. I'd like to turn up TX power as much as possible. But I'm 
concerned that this will damage the RX frontend. Especially if the RX 
gain is set to some high value too. Should I be concerned about that? Or 
does the USRP take care of that automatically? e.g. turn down RX gain 
during transmission?
Even if a transmission is received at the same receiver, I'd expect my 
RX DSP chain to just demodulate that burst and later on this packet 
would be discarded. Also, I'd envision a block that 'blanks' my RX 
samples whenever TX is expected.

All in all the questions are:
- do I need to implement some logic in GR to turn down RX gain (or shut 
off RX) during a TX burst?
- does UHD take care of that?
- If I need to take care of that, how did you guys handle that problem?

Cheers
Johannes