Abstract: An asynchronous time-hopping multiple access "(ATHMA") protocol and a simplex mode communication system utilizing the same requires no synchronization between transmitting stations, no handshaking between transmitters and receivers and no system manager to coordinate data message transmission. The ATHMA protocol ensures that for an n-channel asynchronous simplex mode communication system, each transmitter repeatedly sends each unique data message n successive times according to its own time-hopping schedule. In the preferred embodiment the time-hopping schedules are coordinated such that at least one duplication of each unique message will not collide with any other messages over a given period. Thus, at most n-1 transmissions out of the total n transmissions of each unique data message will be collided and lost. The ATHMA protocol and communication system of the present invention is ideally suited for applications requiring a low throughput rate and channel capacity.