非理想频谱检测对主用户干扰的性能分析

摘要

实际中认知中继网络的频谱检测不可能完全正确检测频谱状态，次级用户传输会对主用户传输产生干扰。在分布式协作频谱检测和集中式协作频谱检测情况下，研究了认知中继网络中非理想频谱检测对主用户干扰性能的影响。在瑞利信道下推导了非理想频谱检测条件下主用户干扰概率的数学表达式。最后，仿真结果证明了理论分析的合理性，并表明非理想频谱检测会对主用户产生较大干扰，而中继节点数目的增加可以明显降低干扰概率。%Due to the imperfect spectrum sensing in practice, the secondary user’s ( SU’s) transmission in-terferes with the primary user ( PU) unavoidably. With distributed spectrum sensing ( DSS) and coopera-tive spectrum sensing ( CSS ) , this paper investigates the impact of imperfect spectrum sensing on PU in cognitive relay networks. The exact expression for interference probability of PU is derived over Rayleigh fading channels. Finally, the theoretical analysis is validated by Monte-Carlo simulations. The results show that, though the imperfect spectrum sensing leads to the interference on PU, an increase of the num-ber of relays can compensate the loss significantly.