We have been testing AD9361 using FMCOMMS3. We observed that the IQ tracking works well and the image component disappears. Using IIO-scope, a simple complex tone was transmitted in order to double check the IQ-tracking functionality.
Fs = 30.72 MHz
Ftone = 0.96 MHz (=Fs/32)
Then, we did a loopback with following parameters with IIOscope:
TXatt: 10 dB
External attenuation: 20 dB (SMA-SMA attenuator)
IQ tracking: ON
DC tracking: ON (RF + BB)
Complex tone from DAC Buffer output or from DDS.
The DAC output seems to have many spurious tones compared to the DDS output:
How could we get as clean output with DAC output as with DDS?