摘要
针对已有差分光空间调制系统(DOSM)中存在的频谱效率不理想问题,利用高能量效率的脉冲位置调制(PPM)和高频谱效率的脉冲幅度调制(PAM),通过构建满足差分过程的空时弥散矩阵,提出一种包含空间域、时间域和数字符号域的高维DOSM(HD-DOSM)方案。在详细介绍HD-DOSM的差分编码原理后,推导了HDDOSM的理论误码率上界,并与DOSM进行了性能对比。结果表明:所提方案实现了频谱效率和误码性能的折中。当频谱效率为1 bit·s^(-1)·Hz^(-1)、误码率为1×10^(-3)时,和基于PAM的DOSM相比,HD-DOSM的信噪比改善了约2 dB,其传输速率增加了2 bpcu(bit per channel use)。利用发送信号的稀疏性,提出了一种先检测PPM符号的分步检测算法,以有效降低接收端译码算法的计算复杂度。当PPM阶数为4时,相较于最大似然检测算法,所提方案的复杂度降低了约75%。
In order to effectively solve the problem of suboptimal spectrum efficiency of a differential optical spatial modulation scheme(DOSM), a high-dimensional DOSM(HD-DOSM) including spatial, time, and digital signal domains is proposed by using pulse position modulation(PPM) with high energy efficiency and pulse amplitude modulation(PAM) with high spectrum efficiency to construct the space-time dispersion matrix which satisfies the differential process. After the differential coding principle is introduced in detail, the upper bound of the theoretical bit error rate of HD-DOSM is deduced, and its performance is compared with the DOSM system. The results show that the proposed scheme achieves a compromise between spectrum efficiency and error performance. When the spectrum efficiency is 1 bit·s^(-1)·Hz^(-1)and the bit error rate is 1×10^(-3), the signal-to-noise ratio(SNR) of HD-DOSM is improved by about 2 dB, compared with DOSM based on PAM. Meanwhile, the transmission rate of HD-DOSM improves by 2 bpcu(bit per channel use). Based on the sparsity of the transmitted signals, a stepwise detection algorithm is proposed to detect PPM symbols first, which effectively reduces the computational complexity of the decoding algorithm at the receiver. When the PPM order is 4, the complexity of the proposed scheme is reduced by about 75% compared with the maximum likelihood detection algorithm.
作者
王惠琴
毛一聪
黄瑞
彭清斌
曹明华
Wang Huiqin;Mao Yicong;Huang Rui;Peng Qingbin;Cao Minghua(School of Computer and Communication,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;School of Electrical Engineering and Information Engineering,Lanzhou University of Technology,Lanzhou,Gansu 730050,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2022年第1期80-88,共9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)。
关键词
光通信
光空间调制
信道状态信息
差分光空间调制
误码率
频谱效率
optical communications
optical spatial modulation
channel state information
differential optical spatial modulation
bit error rate
spectrum efficiency
