I am capturing data using the AD6688 Eval Board and ACE software with the following settings :
NCO frequency set to 1 GHz
I apply 4.1 GHz , 10 dBm tone signal. Against my expectation the the signal has a component at the image frequency (- 100 MHz). Following is the DDCFFT of the capured data:
What is it that I am doing wrong?
I failed to notice that 4100 MHz tone has components at +200 and - 200 MHz not +/- 100 MHz in DDCFFT graph. I also noticed that in the waveform graph I and Q waveforms are in phase.