I am using Xilinx's RFSoC in I/Q mode. The important point is that in the digital space I have real and complex samples. I take the incoming data and multiply it by a complex sinusoid.
In my test setup I am sampling a 125 MHz sine wave and am mixing it with a 5 MHz sinusoid. I take the mixed signal and pass it out a DAC to view it on a spectrum analyzer. What I would like to see is the 125 MHz digitally upconverted to 130 MHz. What I actually see is two tones: 120 MHz and 130 MHz.
Is there a way, without just filtering the 120 MHz sine wave, to upconvert the 125 MHz tone to 130 MHz by mixing?