非理想条件下认知非正交多址接入系统中断性能研究

Outage Performance Analysis of Cognitive Radio Non-Orthogonal Multiple Access System under Non-ideal Conditions

为满足网络需求,提高系统频谱利用率,该文提出一种覆盖式认知非正交多址接入(CR-NOMA)网络。考虑实际中非线性功率放大(NLPA)、非理想连续干扰消除(ipSIC)和非完美信道状态信息(CSI)等非理性因素,研究所提网络的可靠性能,推导出系统中断概率(OP)和系统吞吐量的解析表达式,并进一步分析高信噪比下中断概率的表达式、理想状态下中断概率的高信噪比(SNR)近似、分集阶数。分析及仿真结果表明:NLPA,ipSIC和信道估计误差参数对系统中断概率性能有负面影响;中断概率随着信噪比的增加而减小,在高信噪比下收敛到一个固定常数;中断概率随着功率分配系数的改变也会产生相应的变化。

To meet the network requirements and improve the utilization of system spectrum,a Cognitive Radio Non-Orthogonal Multiple Access(CR-NOMA)technology is proposed.To investigate the system reliability,NonLinear Power Amplification(NLPA),incomplete Successive Interference Cancellation(ipSIC)and incomplete Channel State Information(CSI)are taken into account.The analytical expressions of system Outage Probability(OP)and system throughput are derived,and the expressions of outage probability under high SNR,high SNR approximation of outage probability under ideal state and diversity order are further analyzed.The simulation results show that:NLPA,ipSIC and channel estimation error parameters have negative effects on interrupt probability;The interrupt probability decreases with the increase of SNR until it converges to a fixed constant at a high SNR;Interruption probability will also change with the change of power distribution coefficient.