Log-normal信道下MIMO-FTN-OWC系统BER性能分析  

BER Performance of MIMO-FTN-OWC Communication over Log-normal Fading Channel

作　　者：李文文[1] 曹明华[1] 张悦 王惠琴[1] 刘玲[1] LI Wen-wen;CAO Ming-hua;ZHANG Yue;WANG Hui-qin;LIU Ling(School of Computer and Communication,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学计算机与通信学院,兰州730050

出　　处：《光通信研究》2022年第6期64-69,共6页Study on Optical Communications

基　　金：国家自然科学基金资助项目(61875080,61861026);甘肃省科技计划资助项目(20JR5RA472)。

摘　　要：超奈奎斯特(FTN)技术可以提高无线光通信(OWC)系统的频谱效率,但信号在传输过程中会受到人为引入码间干扰(ISI)和大气湍流的影响,导致系统误码率(BER)性能恶化。针对此问题,文章构建了4阶脉冲幅度调制(4PAM)的多输入多输出(MIMO)FTN-OWC系统,通过采用MIMO技术抑制了大气湍流对信号的影响。在此基础上,推导了该系统在Log-normal信道下的理论BER,并分析了信道间相关性对系统BER性能的影响。仿真结果表明,当BER为10时,2×2 MIMO-FTN系统的BER性能较单输入单输出(SISO)-FTN系统提高了9.5 dB。当信道相关且相关因子低于0.6时,MIMO-FTN系统的BER性能优于SISO-FTN系统。Faster-than-Nyquist(FTN) technology can improve the spectral efficiency of Optical Wireless Communications(OWC). However, it is affected by the artificially introduced Inter-Symbol Interference(ISI) and atmospheric turbulence, which leads to the degradation of Bit Error Rate(BER) performance. To deal with this issue, a PAM modulated Multiple Input Multiple Output(MIMO)-FTN-OWC system is proposed, and MIMO technology is utilized to suppress the influence of atmospheric turbulence. Furthermore, the theoretical BER in log-normal fading channel is deduced, and the influence of channel correlation on the BER performance is analyzed. The simulation results show that the BER performance of 2×2 MIMO-FTN system is 9.5 dB higher than that of Single-Input Single-Output(SISO)-FTN system when BER is 10. In addition, the MIMO-FTN system has better BER performance than that of SISO-FTN system when the channel spatial correlation coefficient is lower than 0.6.

关 键 词：无线光通信 超奈奎斯特 多输入多输出 误码率性能 空间相关性 

分 类 号：TN929.12[电子电信—通信与信息系统]