i am meeting the same problem here. When i am using FDD Independent mode with TXNRX and ENABLE pin, the burst pulse will show at the start of entering "rx state". As the picture shows, I loop an cosine wave back into rx chain of ad9361, using ENABLE pin to turn RX chain on and off periodicly.
Followed discussion from below post as the post is marked assumed answer
AD9361 TDD burst pulses before data
Are you using AGC?
Can you share AGC config details?