基于APD与PIN接收机的UWOC系统误码率性能优化研究  

Study on the BER Optimization of UWOC Systems Based on APD and PIN Receivers

作　　者：史宏强 李岳衡[1] 黄平[1] 谭跃跃 刘陕陕 居美艳[1] SHI Hong-qiang;LI Yue-heng;HUANG Ping;TAN Yue-yue;LIU Shan-shan;JU Mei-yan(School of Computer and Information,Hohai University,Nanjing,Jiangsu 211100,China)

机构地区：[1]河海大学计算机与信息学院,江苏南京211100

出　　处：《电子学报》2022年第2期446-454,共9页Acta Electronica Sinica

基　　金：中央高校基本科研业务费项目(No.2019B15714);国家自然科学基金(No.61832005)。

摘　　要：本文主要研究采用雪崩光电二极管(Avalanche PhotoDiode,APD)和PIN(Positive-Intrinsic-Negative)光电二极管作为接收机时,水下无线光通信(Underwater Wireless Optical Communication,UWOC)系统的误码率(Bit Error Rate,BER)性能及其优化.具体而言,提出并通过数值仿真验证了一种含指向误差的双指数函数路径损耗模型,以更全面地描述清澈海洋水质UWOC的信道特性.基于此模型,在上述两种接收机场景下,分别推导了采用OOK(On-Off Keying)调制时UWOC系统的理论BER闭型表达;以最小化BER为优化目标,证明该优化问题实际上是一个关于接收机倾斜角的凸优化问题,并给出了相应的理论解与数值仿真验证.理论分析和仿真结果均表明:根据理论计算与仿真得到的最佳倾斜角,可以合理地倾斜接收机,相较于未倾斜前的UWOC系统误码性能,其性能提升幅度最大能达到71.68%.The bit error rate(BER)and its associated optimization of an underwater wireless optical communication(UWOC)system employing avalanche photodiode(APD)andpositive-intrinsic-negative(PIN)photodiode as receivers were investigated.For this purpose,a double-exponential path loss channel that takes the pointing error into account was proposed,which was verified by numerical simulations to be more suitable for modeling the characteristics of UWOC under clear ocean water links.Based on this model,the theoretical expressions of system BER were deduced when we adopted onoff keying(OOK)modulation in two different receiver scenarios mentioned above.To minimize the BER further,we proved that the problem is actually a simple convex optimization problem about the tilting angle of the receiver,and then provided possible theoretical solution and its corresponding numerical verifications.Both theoretical analysis and simulation results show that according to the optimal tilting angle obtained by theoretical calculation and simulations,the receiver can be reasonably tilted;and the BER performance can be improved up to71.68%compared with the one before tilting.

关 键 词：水下无线光通信 指向误差 误码率 凸优化 蒙特卡洛数值仿真 

分 类 号：TN929.3[电子电信—通信与信息系统]