一种混合认知RF和MIMO FSO系统的中断概率分析  

Outage Probability Analysis of a Mixed Cognitive RF and MIMO FSO System

作　　者：韩立强[1] 江红兵 Han Liqiang;Jiang Hongbing(School of Electrical Engineering, Yanshan University, Qinhuangdao, Hebei 066004, Chin)

机构地区：[1]燕山大学电气工程学院,河北秦皇岛066004

出　　处：《中国激光》2018年第4期233-240,共8页Chinese Journal of Lasers

摘　　要：给出了一种串联衬底认知射频(RF)网络与多输入多输出(MIMO)自由空间光通信(FSO)链路的双跳传输系统,分析了其中断概率。对于射频链路,采用瑞利衰落分布模型,分析次级用户与主用户共享频谱的衬底认知无线电网络;对于MIMO FSO链路,采用Gamma-Gamma大气湍流模型,考虑大气衰减效应和大气湍流效应,通过等增益合并建立MIMO FSO的信道模型。推导出中断概率的闭合表达式,仿真分析各种天气条件和大气湍流对串级链路的影响,结果显示随着次级用户发射器的峰值发射功率增大和发射孔径与接收孔径的数目增多,大气效应的影响逐渐减小,通信性能随之提高。In this paper,we present a dual-hop transmission system composed of underlay cognitive radio frequency（RF）network cascaded with multiple input multiple output（MIMO）free-space optical communications（FSO）links,and analyze the outage probability.For the RF link,we use the Rayleigh fading distribution model and analyze an underlay cognitive radio network where the secondary users share the spectrum with licensed primary users.For the FSO link,we use the unified Gamma-Gamma turbulence distribution model to establish the MIMO FSO channel model derived with the equal gained diversity combined technique considering the effects of atmospheric attenuation and turbulence.We derive a new exact closed-form expression for the outage probability under fixed amplify-and-forward relay scheme.The influences of various weather conditions and turbulence strength on the cascade link are verified via computer simulations.The results indicate that the performance of the mixed underlay cognitive radio network and MIMO FSO system is increased and the atmospheric effect is decreased gradually with the increase of the peak transmission power of secondary user transmitters and the number of transmitting aperture and receiving aperture.

关 键 词：光通信 自由空间光通信 双跳中继系统 中断概率 衬底认知无线电 

分 类 号：TN929.1[电子电信—通信与信息系统]