Periodic spikes in AD9364 I Q data


While I was working with AD9364 with ZedBoard, I noticed that, If I move the signal out of the band little bit, I notice spikes on both I and Q data. I added some screenshots to show this behaivour.

Normally what it should be (noise) : 

What I get : 

Spikes close up : 

My setup is LO frequency is at 2 ghz, single sinusoidal signal at 2.001 ghz, using fir filter below, slow attack auto gain is enabled.

AD9361_RXFIRConfig rx_fir_config = {
3, // rx
-12, // rx_gain
4, // rx_dec
{-103,82,-109,148,46,243,159,215,55,-10,-168,-179,-169,-14,126,274,277,179,-51,-268,-413,-359,-141,197,476,578,402,15,-445,-746,-735,-356,244,814,1061,830,156,-683,-1310,-1379,-787,280,1359,1932,1636,492,-1076,-2360,-2688,-1733,256,2494,3921,3667,1479,-2023,-5454,-7087,-5493,-143,8263,17891,26295,31184,31184,26295,17891,8263,-143,-5493,-7087,-5454,-2023,1479,3667,3921,2494,256,-1733,-2688,-2360,-1076,492,1636,1932,1359,280,-787,-1379,-1310,-683,156,830,1061,814,244,-356,-735,-746,-445,15,402,578,476,197,-141,-359,-413,-268,-51,179,277,274,126,-14,-169,-179,-168,-10,55,215,159,243,46,148,-109,82,-103}, // rx_coef[128]
128, // rx_coef_size
{800000000,25000000,8333333,4166667,2083333,520833}, // rx_path_clks[6]
434750 // rx_bandwidth

Best regards,


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