A digital computer simulation of a frequency-modulation differentially coherent phase-shift-keying (FM-DCPSK) system is described. This simulation program is used to investigate the effect of intersymbol interference on the error-rate performance of the two- and four-phase system. Nyquist channels have been obtained and verified. Performance curves are presented to facilitate system design.

This paper examines the analog methods presently used in carrying digital signal via the terrestrial microwave radio relay systems. It then summarized the state of the art of two proposed digital radio systems, operating above and below 10 GHz. It also highlights some of the problem areas yet to be solved, with particular emphasis on these design problems associated with the high-capacity system. An extensive bibliography is given for easy reference.