AnsweredAssumed Answered

finding time offset in tx/rx signal path

Question asked by stevereine Employee on Oct 3, 2017
Latest reply on Oct 3, 2017 by travisfcollins

Can someone please review the technical request from one of our 5G customers below?  Thanks
We are testing the ADI9371 RF transceiver and we are having some issue in decoding the incoming signal from UE received on RX1 port and processed through the FFT and analyzed the data in MATLAB. Basically we are observing some time sample offset. But when we use loopback RF cable from TX1 to RX1, send data to iFFT processing and then feed to JESD through TX1. Is there anything we can do on AD9371 card to debug/fix this issue, or is there any data we can dump which can help.
LTE Symbol Data -> iFFT -> DDC -> JESD -> TX1 -> UE -> RX1 -> JESD -> DUC -> FFT -> LTE Symbol Data ==== > we see time offset and in MATLAB it can decode the LTE signal
LTE Symbol Data -> iFFT -> DDC -> JESD -> TX1 -> Loopback -> RX1 -> JESD -> DUC -> FFT -> LTE Symbol Data ==== > we are able to decode the signal in MATLAB after doing some time offset adjustment in DUC-FFT processing. But we are not sure how to find out the time offset when UE is connected.
Note that we are using wired network environment.