标记型多层光空间脉冲位置调制  

Marked Multi-Layer Optical Spatial Pulse Position Modulation

作　　者：王惠琴[1] 叶归清 彭清斌[1] 包仲贤[1] 曹明华[1] Wang Huiqin;Ye Guiqing;Peng Qingbin;Bao Zhongxian;Cao Minghua(School of Computer and Communication,Lanzhou University of Technology,Lanzhou 730050,Gansu,China)

机构地区：[1]兰州理工大学计算机与通信学院,甘肃兰州730050

出　　处：《光学学报》2022年第14期59-68,共10页Acta Optica Sinica

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

摘　　要：现有光空间调制存在传输速率低、发射器利用率低和误码性能不理想等问题,利用分层空间结构,并结合脉冲位置调制(PPM),提出了一种标记型多层光空间PPM(MMLOSPPM)。它利用额外扩展的每个PPM符号内的时隙进行层标记,提高了首先检出层及其调制符号的正确性。此外,推导出了Gamma-Gamma湍流模型下系统理论误比特率的表达式,并用蒙特卡罗方法对其进行了验证。结果表明:当频谱效率为3/2 bit·s^(-1)·Hz^(-1)时,(5×4-2-2)MMLOSPPM系统的传输速率相较(4×4-2)空间PPM(SPPM)和(3×4-2)广义SPPM(GSPPM)改善了3 bpcu(bit per channel use);在传输速率相同的条件下,(5×4-2-2)MMLOSPPM系统所需要的激光器数目分别比(7×4-4)GSPPM和(16×4-4)SPPM节约了2个和11个,并且在大信噪比(SNR)区域(SNR大于28 dB)中MMLOSPPM系统获得了最好的误码性能。The existing optical spatial modulation has some problems,such as low transmission rate,low transmitter utilization rate and undesirable bit error rate performance.A marked multi-layer optical spatial pulse position modulation(MMLOSPPM)scheme is proposed by employing the layered spatial structure and combining pulse position modulation(PPM).The timeslot of each PPM symbol is extended to distinguish layers,and the correctness of the first detection layer and its modulation symbol is improved.Besides,the theoretical bit error rate expression of the MMLOSPPM system is derived under the Gamma-Gamma turbulence model and is verified by Monte Carlo method.The simulation results show that when the spectral efficiency is 3/2 bit·s^(-1)·Hz^(-1),the transmission rate of(5×4-2-2)MMLOSPPM is 3 bpcu(bit per channel use)better than that of(4×4-2)spatial PPM(SPPM)system and(3×4-2)generalized SPPM(GSPPM).When given the same transmission rate,the(5×4-2-2)MMLOSPPM system requires 2 and 11 fewer lasers than that of(7×4-4)GSPPM and(16×4-4)SPPM system respectively,and MMLOSPPM gains the best bit error rate performance in the high signal to noise ratio(SNR)region(SNR is greater than 28 dB).

关 键 词：光通信 无线光通信 光空间调制 脉冲位置调制 多层光空间调制 

分 类 号：TN929.2[电子电信—通信与信息系统]