Design and performance analysis of Asynchronous Physical-layer Network Coding system

For Physical-layer Network Coding (PNC), the problem of the symbol misalignment is a focus field. In this paper, we present an effective method to detect the number of symbol misalignment by utilizing Zadoff-Chu sequence (ZC sequence). Based on this method, we propose a joint communication system of Asynchronous Physical-layer Network Coding (APNC) and an Improved ZC sequence (IZC) based on BPSK modulation (IZC-APNC). In this system, we design a rule to the relay's symbol misalignment mapping, and correspondingly derive mathematical expressions of data processing. The simulation results show that our proposed system can effectively solve the problem of the symbol misalignment in APNC and improve the reliability of system transmission information.