This thesis is aimed at the problem of quickly and accurately communicating digital data between fixed and mobile (either vehicle-mounted or hand-held) radio stations. Digital error is of prime concern and the effects which multipath propagation, Gaussian noise, and implusive noise have on digital errors are analyzed. The importance of other analyses such as economic factors, interrogation procedures, or analog transmission might be peculiar to land mobile communication, but the recommendations for improving the noisy, fading digital channel should have broader application and a more general appeal.