Phase shift keying (PSK) is a large class of digital modulation schemes. PSK is

widely used in the communication industry. In this chapter we study each PSK modulation

scheme in a single section where signal descr iption, power spectral density,

modulator/demodulator block diagrams, and receiver error performance are all included.

First we present coherent binary PSK (BPSK) and its noncoherent counterpart,

differential BPSK (DBPSK), in Sections 4.1 and 4.2. Then we discuss in

Section 4.3 M-ary PSK (MPSK) and its PSD in Section 4.4. The noncoherent