In this paper, transmitted signal leakage(TSL) and propagation delay in wireless communication system are studied; Firstly, a baseband digital model of TSL pollution is established, the time variation of the polluted channel and the propagation delay to the receiver is considered in this model, and the TSL time-varying channel based on the first-order autoregressive model is analyzed and established. Secondly, the complex gain estimation of TSL time-varying channel is obtained based on the least mean square algorithm, and a discrete time observation model is established to implement the compensation of TSL pollution and propagation delay. The asymptotic performance expression of the compensation algorithm in the case of uncompensated fractional delay is obtained. Finally, a digital compensation algorithm based on the joint estimation of complex channel time-varying gain and fractional delay is proposed by analyzing the complex channel gain estimation and fractional delay influence in the case of synchronization. The simulation experiment results show that the proposed joint estimation compensation algorithm is not only effective and robust, but also has better signal interference ratio performance and lower complexity than the multi-tap LMS solution and other advanced schemes.