Cooperative Communication with Physical-layer Network Coding in Cognitive Radio Network

Cognitive radio technology is a promising technology to solve the inefficiency problem of the usage of spectrum, and with the help of the cooperative communication technology, the system can obtain more performance. This paper proposes a cooperative communication strategy based on physical-layer network coding (PNC) to work out the difficulty that the primary cannot communicate, which the secondary user can also access the spectrum. Meanwhile, we also discuss the power allocation scheme and relay selection strategy to maximum the system capacity. With amplify forward (AF), the secondary forwards the signal after orthogonal zing the single of the primary user and the secondary user. Simulation results showed that, with the cooperation of the secondary user, the primary user can communicates efficiently; the secondary user transmits availably as well. The system achieves the best performance by the power allocation scheme and relay selection strategy.