独立不同分布Nakagami-m衰落信道下最大比合并性能分析  

A Performance Analysis of Maximal Ratio Combining under Condition of Non-Identically Distributed Nakagami-mFading Channels

作　　者：李涛[1] 蒋磊[1] 陈博文 LI Tao;JIANG Lei;CHEN Bowen(Information and Navigation College,Air Force Engineering University,Xi'an 710077,China;Unit95844,Jiuquan735000,Gansu,China)

机构地区：[1]空军工程大学信息与导航学院 [2]95844部队

出　　处：《空军工程大学学报（自然科学版）》2018年第6期84-89,共6页Journal of Air Force Engineering University(Natural Science Edition)

基　　金：国家自然科学基金(61601500)

摘　　要：为研究独立不同分布(i.n.d.)Nakagami-m衰落信道下的分集接收系统采用最大比合并(MRC)时的系统性能,以输出信噪比的概率密度函数为基础,导出了系统中断概率的精确解并给出中断概率数值解的一种获得方法。根据输出信噪比的矩生成函数,推导出不同调制方式下系统平均误符号率的Chernoff上界、渐进分集增益和有效分集增益的表达式,并仿真验证了其正确性。仿真结果表明:增加分集支路数能够很大程度地减小系统平均误符号率,提高分集增益,但同时各支路衰落不平衡程度对系统性能的影响变大,各支路衰落不平衡程度在信道衰落越小时对中断概率影响越大。For convenience of studying the performance of the maximal ratio combining (MRC)diversity system under condition of non-identically distributed (i.n.d.)Nakagami-m fading channels,both the exact solution of the system outage probability and a method for obtaining the numerical solution of the outage probability are concluded based on the probability density function of the output signal to noise ratio (SNR).In accordance with the moment generation function (MGF)of the output SNR,the expressions of Chernoff upper bound of the average symbol error rate (ASER),the asymptotic diversity gain and the effective diversity gain under different modulation methods are obtained,and the correctness is verified by simulation.The simulation results indicate that with the increase of the number of diversity branches,the system's average symbol error rate decreases,and the diversity gain is enhanced.Simultaneously,the degree of fading unbalance for each branch has a greater impact on the system performance.Besides,the smaller the degree of channel fading,the greater its impact on the outage probability.

关 键 词：Nakagami-m衰落 最大比合并 矩生成函数 平均误符号率 分集增益 

分 类 号：TN911.2[电子电信—通信与信息系统]