基于SC分集的混合FSO/RF航空通信系统性能分析  

Performance analysis of hybrid FSO/RF airborne communication system based on SC diversity

作　　者：刘文亚 赵尚弘[1] 王翔[1] 牟迪 LIU Wen-ya;ZHAO Shang-hong;WANG Xiang;MU Di(Information and Navigation College,Air Force Engineering University,Xi′an 710077,China)

机构地区：[1]空军工程大学信息与导航学院,陕西西安710077

出　　处：《激光与红外》2020年第5期525-531,共7页Laser & Infrared

摘　　要：研究了基于选择合并(SC)分集的混合激光/射频(FSO/RF)航空通信系统性能,该系统设计简单且在发射端无需信道状态信息(CSI)。激光链路服从平均孔径效应下的Exponentiated Weibull大气湍流分布模型,射频采用Nakagami-m衰落信道模型,推导求出混合FSO/RF航空通信系统接收端信噪比的累积分布函数,进一步利用Meijer′s G函数推导了混合FSO/RF通信系统中断概率以及平均误码率的闭合表达式,通过仿真对比分析了不同湍流强度、调制方式及分集通信方案对系统中断、误码性能的影响。仿真结果表明,混合FSO/RF航空通信系统有效地利用了FSO及RF链路在不同大气信道条件下的互补性质,具有更优的中断和误码性能;采用BPSK调制能有效降低大气湍流对混合FSO/RF航空通信系统的影响;信噪比高时,并行传输、分集接收的通信方案对系统误码性能的改善要优于低阶调制对误码性能的改善。In this paper,the performance of hybrid Free Space Optical/Radio Frequence(FSO/RF)airborne communication system based on selection combining(SC)diversity is analyzed.The system is simple in design and does not require channel state information(CSI)at the transmitting end.The FSO link is modeled by the Exponentiated Weibull distribution and the RF link experiences the Nakagami-m fading.For the hybrid FSO/RF airborne communication system,we derive closed form expressions for the cumulative distribution function(CDF)of the signal-to-noise ratio at the receiving end.The closed expressions of the outage probability(OP)and the average bit error rate(BER)are further deduced in terms of Meijer′s G function.The effects of different turbulence intensity,modulation mode and diversity communication scheme on the OP performance and the BER performance are analyzed by simulation.The simulation results show that the hybrid FSO/RF airborne communication system has better BER performance and OP performance than the single FSO system and the single RF system.Using BPSK modulation can effectively reduce the impact of atmospheric turbulence on hybrid FSO/RF airborne communication system.When the signal-to-noise ratio is high,the communication scheme of parallel transmission and diversity reception improves the BER performance of the system better than the low-order modulation.

关 键 词：FSO/RF通信系统 SC分集 Exponentiated Weibull分布模型 NAKAGAMI-M衰落信道 平均误码率 中断概率 

分 类 号：TN929.1[电子电信—通信与信息系统]