摘要
无线光通信多路信号传输时,信号线的互感与互容会引发串扰噪声。为增强光通信抗干扰能力,设计一种基于稀疏采样的多路信号串扰自适应抑制方法。计算信道噪声功率均值,分析了时频明确信号特征分布情况。利用射线定义通信系统跳变单频脉冲电磁波信号传输损耗,得到无线光通信系统信道模型;降采样中频信号,使用匹配滤波器多路并行搜寻码相位,运用快速傅里叶变换法串行计算输入信号与匹配滤波器指数相乘的叠加值;采用主分量分析与小波降噪预处理串扰信号,推算串扰信号与信号伪随机序列的稀疏状态,构建信号稀疏字典与串扰稀疏字典来分离信号与干扰特征,完成信号串扰自适应抑制。实验结果证实,所提方法可以有效分割干扰信号,信号串扰抑制效果较好。该方法的误码率低,平均误码率为10-3,并且抑制串扰的耗时均低于1.3 s,大幅提升了无线光通信系统信号抗干扰性能。
When wireless optical communication is transmitted in multiple signals,crosstalk noise is caused by the mutual inductance and compatibility of signal lines.In order to enhance the anti-interference ability of optical communication,an adaptive suppression method of multi-channel signal crosstalk based on sparse sampling is designed.The average channel noise power is calculated,and the time-frequency clear signal characteristic is analyzed.The channel model of wireless optical communication system is obtained by using rays to define the transmission loss of single-frequency pulse electromagnetic wave signal of the communication system.Downsampling the IF sampling signal,using the matching filter to search for the code phase,and using the fast Fourier transform method to serially calculate the superposition value of the exponential multiplication of the input signal and the matching filter index.The crosstalk signal is preprocessed by principal component analysis and wavelet denoising,the sparse state of crosstalk signal and signal pseudo-random sequence is calculated,and the signal sparse dictionary and crosstalk sparse dictionary are constructed to separate the signal and interference characteristics,so as to complete the adaptive suppression of signal crosstalk.The experimental results confirm that the proposed method can effectively segment the interference signal,and the signal crosstalk suppression effect is better.The bit error rate of this method is low,the average bit error rate is 10-3,and the time-consuming of suppressing crosstalk is all less than 1.3 s,which greatly improves the signal anti-interference performance of the wireless optical communication system.
作者
胡恢军
周菁菁
邓锋
HU Huijun;ZHOU Jingjing;DENG Feng(Nanchang Jiaotong Institute,Nanchang 330100,China;East China Jiaotong University,Nanchang 330044,China)
出处
《激光杂志》
CAS
北大核心
2023年第6期177-181,共5页
Laser Journal
基金
江西省教育厅科研课题(No.GJJ2020171488)。
关键词
无线光通信
多路信号
串扰抑制
通信信道
稀疏采样
wireless optical communication
multiple signals
crosstalk suppression
communication channel
sparse sampling
