Abstract: Usually, the quality of signal will decrease in the multipath signal transmission of high rate modulated signals. In this paper, time reversal arithmetic for multipath signal transmission is researched. According to the known multipath transmission function, by transmitting the time reversal signal, the required signal will focus on the receiver location, thus S/N ratio of signal can be improved, waveform can be optimized, and code error rate can also be reduced, which can mitigate the influence of multipath transmission. This arithmetic is proved to be effective by the injection test.