Modulation techniques for multiple access to a hard-limiting satellite repeater

This paper considers the problem of devising modulation techniques that allow a large number of earth stations to use, simultaneously, a satellite repeater with the transfer characteristics of a wide-band hard-limiting amplifier. Four distinct classes of modulation techniques and their singular properties are described. Three important design considerations are discussed: repeater bandwidth and power sharing, network timing, and operational considerations. The paper provides a framework for further study of the multiple access problem. The hard-limiting repeater is shown to accommodate a wide variety of signal designs. No single class of multiple-access modulation techniques is found to be uniformly best in satisfying all needs of the diverse networks which can use communication satellites.