SISO TDD OFDM Video Streaming on NI USRP RIO or FlexRIO

[Wired_]

Hello!

How has the Full Duplex been insured in USRP RIO?

As per the docuement of this example simultaneous receiver transmission chain is possible on same frequency. If I am taking it right has self-interference component from transmitting antenna Tx1 and RX1  been fully cancelled for for Full Duplex Implementation.

Or the FD is possible for some antenna arrangement?

Thanks 

[4Matted]

I am not 100% sure if I am understanding your question, but it appears that you are asking if transmitting and receiving at similar frequencies will cause interference and the answer is yes. It is my understanding that there is nothing internal to prevent self interference. Does this answer your question? If not if you could try to clarify for me it would be much appreciated.

[brooksprumo]

jay_phy, the full duplex VIs from the USRP RIO and FlexRIO sample projects do simultaneous transmit and receive on different ports. Your question implied to me that you were wondering about transmitting and receiving on the same port at the same time, which is not possible. In addition to the USRP RIO and FlexRIO 5791 having dedicated transmit and receive ports, the USRP RIO supports time division duplexing on the TX1 RX1 port. Hopefully that helps some!

[Wired_]

Thanks for joining the thread.

1. I meant as name suggest if it's Full-Duplex TDD streaming TX1 and RX1 shlould be having transmitter and receiver running simultaneously! 

This shall mean there is intereference at RX1 due to transmitted stream from TX1. If no correction is being implemented how is full duplex communication possible?

Or here the system is like it's single USRP implementation where TX1 transmits and RX1 receives the transmission from TX1 only not from any other USRP.

As I could see from figure in case of Mobile and Base-Station (both at different USRPs) configuration, there are Uplink and Downlink transmission. Technically uplink and downlink should happen in different/consecutive time solts to avoid self interference. This becomes standard TDD system.

Where is full duplex system in this model? Or am taking wrong meaning of full duplex?

[Wired_]

Thanks! I tried to clear my doubt in earleir reply.

I am worried if Full Duplex means both uplink and downlink chain is working simultaneously. If not its a normal TDD sytem not FD. Am I right? 

Even you receive on different ports there would be self interference.

For TDD Tx1 sends data and stops for moment when Rx1 receieves and chain carries on.

I am interested in measuring channel of uplink and downlink. If I can measure in same time suing Full duplex that would be wonderful as I wont be wasting time in switching.

Though I see there is added advaantage over previous USRP versions where I would else have to waste more time to switch single chain in between RX and TX for my purpose!

If there is some discripancy help me clear the same. Thanks!

[Wired_ · Accepted solution]

Figured out that here Full Duplex does not mean the full duplex we talk about in contemporary papers i.e simultaneous transmission and reception.  Here its a TDD system where two data sources can be streamed both in uplink and downlink, for example as in no-loopback condition.  Two simultaneous, though multiplexed in time, streams: uplink( user to base station) downlink( base station to user).