Abstract: Aimed at PCM/FM reentry remote sensing systems existed in multipath-Induced, the characteristic of amplitude, phase, group delay of the two-path model is analyzed based on presenting some typical theoretical models of reentry remote sensing transmission channel. And the effects on receiver (which are cause by the change of amplitude distortion), group delay distortion, bit rate and channel attenuation factor are analyzed by using two-path model. Delay distortion can cause large amplitude variance of receiving signal. And the joint action between delay distortion and channel attenuation factor influences receiver's performance boundary. Increasing bit rate alone directly leads to worse capacity parameters of the system. The simulation results give references to design reentry remote sensing system rationally in engineering application.