多天线频谱共享CR-NOMA系统安全中断性能分析

Secrecy outage performance of multi-antenna spectrum sharing CR-NOMA system

认知无线电(CR)非正交多址接入(NOMA)网络(记为CR-NOMA)已是无线通信领域的研究热点之一。由于无线信道的开放性,使得无线网络的安全通信成为当前急需解决的问题。该文研究了频谱共享多天线CR-NOMA网络安全中断性能,首先分析了最优天线选择(OAS)方案的安全中断概率(SOP),并推导了其精确的闭合表达式。其次,分析了空时传输(STT)方案的SOP,并推导了其精确的闭合表达式。最后,对次用户两种方案的SOP渐近性能进行了分析,揭示了系统参数对SOP的影响。最后,采用Monte Carlo仿真验证了理论分析的正确性。研究发现,两种方案基站分别存在一个最优峰值发射功率,使得远距离次用户的安全中断性能最佳。仿真结果表明增大基站峰值发射功率,OAS方案的近距离次用户的SOP会始终优于STT方案,远距离次用户的SOP会劣于STT方案。

Cognitive radio(CR)non-orthogonal multiple access(NOMA)network(recorded as CR-NOMA)is one of the research hotspots in the field of wireless communication.Due to the openness of wireless channel,the security communication of wireless network becomes an urgent problem.For the spectrum sharing multi-antenna CR-NOMA network,First,the secrecy outage probability(SOP)of the optimal antenna selection(OAS)scheme is analyzed,and its exact closed-form expression is derived.Secondly,the SOP of space-time transmission(STT)scheme is analyzed,and its exact closed-form expression is derived.Then,the asymptotic secrecy performance of secondary user SOP is analyzed to reveal the influence of system parameters on the secrecy communication performance.Finally,the Monte Carlo simulation is used to verify the correctness of theoretical analysis.It is found that there is an optimal transmit power in the base station under two schemes,which makes the secrecy outage performance of secondary user the best.The simulation results show that increase the peak transmission power of the base station,the secrecy outage performance of close secondary user under OAS scheme is always better than that of STT scheme,the secrecy outage performance of remote secondary user will be inferior to that of STT scheme.