We use AD9361 with No-OS drivers configuration and We have the following problem:
1. When We transmit a pulse with the amplitude that is 2000, pulse width is 1 microsecond and PRI is 4 microseconds everything is ok
2. When We transmit a barker modulated pulse which has amplitude that is 2000 or -2000, pulse width is 1 microsecond and PRI is 4 microseconds, We see an echo from Tx signal on Rx channels, after 120-140 clocks
We use a FIR filter with gain=-6 dB.
We have tried to lower the amplitude it did not help.
Our used sample rate is 60 Msps.
What can be the reason for this problem?