I am doing some test of Fmcdaq2 through ADI oscilloscope, I have found that the default sampling frequency of both ADC and DAC are set at 1GHz, and the output frequency of DAC is 500MHz. I loaded a file which is a 16QAM signal, and got the constellation diagram like below,
Then I checked the I/Q signal in Time Domain like these, which are irregular waveforms (of course they should be)
Here are my questions:
1. What's the DAC output frequency for each bit data? Is it still 500MHz? Since I counted the bit number,which is 25, each 0.05us.
2. Since the file Ioaded is generated from matlab (attached below), are the waves I checked already added to carrier waveform signals which are cos(wt) for I channel and sin(wt) for Q channel ? (I am sorry this may be a stupid question but wondering the answer.)
Hope anyone with experience can help me or give me a little hint.
Thank you so much!!!!