Wave Communication Anti-multipath Technology Research

Shortwave channel is time varying transmission channel.It has dispersion in frequency and time domains.This characteristics hinds the data transmi- ssion at high speed and the correction of received data.In this dissertation I have analyzed the statistic characteristic of shortwa-ve channel,established the model of shortwave channel and simulated the Rayleigh fading distribution. The technology of spreading spetrum has been proved that it has the capability for anti-multipath and discerning multipath. I have introduced the technology of diversity and conventional RAKE technology.The main contribution of the dissrtation is that I have applied the betteradaptive RAKE algorithm to shortwave channel. The algorithm has less computation and more quick ability to trace channel. The result of computer simulation has showed the adaptive algorithm can quickly tracing the change of shortwave channel and constrain from the affection of noise.The combination of DS-spreading spectrum technology with adaptive RAKE tech-nology can reduce BER of data transimission and raise the transmitted speed.