Demodulating P25 CQPSK Signals Using a C4FM Receiver

Usually a modulation of one species can only be demodulated with the radio signal processing chain of the same species. But P25 has a very interesting and unusual concept of demodulating a signal from one modulation species using the receiver of another species. APCO Project 25, commonly known as P25, is a suite of digital radio standards designed for public safety and first responder…