Hi all,
I have two transceivers A and B each one is connected by cables to a USRP B200mini (TX/RX for send and RX2 for receive)
Using GNU Radio, for each iteration, transceiver A starts to send a burst of RC-filtered, BPSK-modulated PN sequence.
Side B waits for the burst and as soon as it gets that (by correlation), detects the
phase ramp (because of the carrier frequency offset (CFO)) on the PN symbols
and makes a new burst with the same phase ramp, and sends its burst back to side A.
Then I observe the phase of the received symbols at A.
As far as there is no sample loss/insertion, I suppose the phase continuity is held and
should receive a constant phase on the received symbols at A whose value depends
on the delay between A and B which is fixed.
I observe these issues:
1- in some iterations, the received phase at A is not fixed.
2- in some iterations, the received phase at A is fixed but does not equal other iterations.
Would be grateful if anyone could help me with this.
Thanks!