Hi,
I am generating a BFSK signal at mark frequencies 18k and space frequencies 22k then performing FM modulation on it. when i observed the same FM signal at RF 430M Center Frequency in R&S spectrum analyzer. i see some side bands generated on either side of the carrier frequency. Also I checked the IF signal at 25M, these side bands are present there also.
My hardware is as follows
5641r IF transceiver
5610 Rf upconverter.
I found that 5641R does not have band pass filters integrated on it.
i would like to know, how these sidebands are removed from FM signal.
Thanking you