Signal synchronization problem is a hot research of physical layer network coding, in order to improve the channel capacity of the system and robustness, in view of high error rate problem in asynchronous communication, a wireless commuting method was put forward that based on physical-layer network coding and convolution channel coding. Firstly, belief propagation algorithm was introduced to the relay node coding, and then the convolution channel decoding and physical layer network coding were used to solve the adverse effects caused by asynchronous communication, finally, the simulation experiments were carried out to test its validity and superiority. The simulation results indicated, compared with other coding methods, the method not only reduces the error rate of data transmission enhances the system reliability of communication and information transmission rate, but also enhances the system robustness to phase offset and symbol offset, and has higher practical application value.