There are a number of great tutorials online explaining phase shift keying as a means of digital wireless communication, but none of them seem to cover the topic of multiplexing. At first glance, it seems that frequency division multiplexing (FDM) would work for PSK, but whenever I flip the phase at the zero crossing, it appears the signal naturally gains high harmonics that interfere with higher bands of the communication medium. Is there something I'm missing? Is FDM even possible on a PSK signal?
P.S. I am new to Stack Exchange and wireless communication in general, so go easy on me. I looked for a Stack Exchange directly related to wireless but didn't find it. If it exists, sorry I wasted your time. Just point me in the right direction.