Hi ad9361 experts:
When I used vivado to observe the rx signal, and found that I/Q signal was too large with peak clipping. As the picture below shows:
The value of the I/Q signal sometime is 0xffff, which reaches the peak. I am using FAGC. I tried to lower the overload threshold, but the problem still existed. And I changed gain control mode to MGC, and lower the gain, still not solved. Could you give me some advice?
Thanks a lot.
I am using just RX1
What is the input signal power that is fed at Rx port ?
If you are looping back Tx to Rx put 20 dB attenuation on Tx path and try.
Thanks for your reply. I make tx1 attenuation even to 40dB, still not solved. I am using FAGC, I guess the ad9361 itself adjusts the gain to a very high value. But I dont know how to lower the gain it locks to. When I set tx1_attenuation to 20dB, the gain locks to 40dB. I even change the agc_inner_thresh_high to a lower value(-20dBFS), still not work. Is there anything that I missed?
Thanks a lot.
Besides, what does the normal I/Q signal look like? Thanks
Are you looping back tx to rx? Instead of looping back can you give a fixed amplitude tone at rx input, set the gain mode to fast attack and then see the Rx output.
Thanks for your reply. Forgive me for not answer your question. I am not looping back tx to rx. I inputed a fixed amplitude signal at rx input, and set the gain mode to fast attack. Still the Rx output peak clipping, any suggestion please? Thanks a lot.