I have been trying to do some research using MIMO transmitters and feedback from a receiver.
Specifically, I have two antennas connected to two USRPs, and I am transmitting the same signal from both of those (MIMO synchronized) to another USRP and antenna.This receive USRP and antenna needs to measure its received power, which I then feed back to my computer, do some processing on it, and then produce a new transmission from the two antennas on the left, and that keeps going until my loop is done.
What I'm having trouble with is how to set up my self-created block to transmit from the two synchronized ones with my particular weights but also receive from the one on the right correctly so that it gives me the proper received power. Right now, I'm doing both the transmit and receive processes independently, and it's very difficult to get the proper capture on the receive side and send it back.
I'm not sure if that makes sense, but that type of feedback has been very difficult. Note that I've been able to create this loop, block, and feedback setup with an RSSI circuit and the two transmitters because I can feedback its reading through USB nicely/if not with a bit of a hack using minicom. I just can't do it when the receiver is a USRP. I must be missing something. Thank you for any help.
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