I have built a prototype board using an AD630 balanced modulation circuit (gain of 1). I have verified this circuit works because I have tested it with a 1 kHz sine wave carrier and modulated a 100 Hz sine wave. I, then, acquired this data and brought into MATLAB where I want to demodulate the signal digitally. However, when I tried using frequency modulation it does not work. I read deeper into the data sheet and it said that the output of the AD630 is a double sideband suppressed carrier waveform, but it does not mention if it is AM or FM. I looked into MATLAB's built in signal processing and they have an AM double side band suppressed carrier demod, but it doesn't work either.
Has anyone experienced this problem and have an way to remedy it?