Commutation Signaling - An Antimultipath Technique

Abstract

Two types of commutation signaling for combating multipath are introduced:M \times Nsignaling, in which the signal set cycles successively amongNdifferent sets ofMsigals each; andM + Nsignaling, in which the signal set at any time consists ofMmembers of an alphabet ofM + Nsignals,Nof which are inactive at any epoch. In both cases, the objective is to remove from use any signal sent recently enough that it is still "ringing" in the multipath channel. We consider the problems of minimization ofMandN, hence the total number signals used; analysis of2 \times Nsets (M = 2is almost uniformly optimal); analysis of the simplestM + Nset, i.e., a 2 + 1 set; and presentation of the results of simulation ofM \times NandM + Nsignaling through realistic urban/suburban radio channels. Comparison of these simulations to simulations of other antimultipath techniques is also made. The simulation results are due to Kamil [3].