Capacity of bandlimited phase only modulated systems in AWGN [satellite channels]

The authors discuss the maximum rate at which data can be reliably communicated through an AWGN channel where phase only modulation is used, and the reduction of the maximum rate if the demodulator in the system responds only to the phase of the modulated signal. They then look at how these rates are reduced if the modulator is restricted to a finite set of phase symbols (such as in 8 or 16-PSK systems) and how the rates compare with the maximum rates for hard decision detected systems