Point-to-point mobile underwater acoustic (UWA) communication is one of the key technologies for UWA networks which consists of mobile and stationary nodes. The mobile communication UWA channels are analyzed, whose eigen rays have different Doppler shifts which enhances the complexity of intersymbol interference (ISI) caused by the multipath channel, that goes against the UWA communication. The channel equalization using single sensor passive phase conjugation mirror (PPCM) is proposed to compensate for the Doppler shift in real time and to focus the multipath signals. The application of single sensor PPC to communication system based on Pattern time delay shift coding scheme is carried out in lake trials. The results of lake trials validated the capability of PPCM mitigating ISI and the robustness of the communication system.