Continuous Phase Frequency Shift Keying ( CPFSK )

Abstract Continuous Phase Frequency Shift Keying (CPFSK) is a modulation that, as its name implies, can be characterized as a traditional frequency shift keyed (FSK) signal constrained to maintain continuous phase at its symbol time boundaries. This constraint offers important advantages in error rate performance as well as signal spectrum containment. In this paper, the modulation is introduced and its relationship to the more general Continuous Phase Modulation (CPM) is outlined. The spectrum of CPFSK is presented and optimal coherent and noncoherent receiver structures are developed. Finally, the coherent and noncoherent error‐rate performance of CPFSK is presented.