Control of AD9361 ( 2R2T ) mode

Dear all

I am using AD9361(ADRV9361-z7035) in FDD Independent mode .I want to control Tx and Rx of AD9361 independently through some logic. My objective is that whenever "X" frequency is fall on Rx(detected by Rx-FFT-threshold logic ). I want to transmit this frequency on Tx ( I already done this , ) but I want to transmit that detected frequency continuously on Tx( for some millisecond ) .I inserted a logic that whenever a frequency detected . Turn Off RX path and Turn ON Tx path ( but the issue is that whenever the RX path is turn off , at the same time tone is disappear . the board is running like loopback (from RX----TX) . My requirement is that Tx keep transmitting the detected frequency for some millisecond .Any reference document or suggestion from your side .?