激光测距的空间卷积神经网络信号处理研究  

Signal Processing of Spatial Convolutional Neural Network for Laser Ranging

作　　者：白一波 潘康立[1] 耿林[1] Bai Yibo;Pan Kangli;Geng Lin(North China Research Institute of Electro-Optics,Beijing 100015,China)

机构地区：[1]华北光电技术研究所,北京100015

出　　处：《中国激光》2021年第23期32-42,共11页Chinese Journal of Lasers

摘　　要：激光测距在现代激光应用领域已经得到了广泛的应用。针对远距离激光测距中弱信号探测的问题,研究了一种基于阵列雪崩光电二极管(Avalanche Photon Diode,APD)探测器的光子计数法与卷积神经网络相结合的综合信号处理方法,从理论与仿真两方面验证了该方法的有效性。该方法可提升信号识别能力。提出了光子计数法和卷积神经网络相结合的空间三维卷积神经网络信号处理模型,该模型通过三级信号辨识,能够在"强背景、弱信号"情景下将信号光的辨识度提升近一倍。Objective The laser distance measurement system is widely used in various fields such as long-distance measurement,atmospheric concentration monitoring,three-dimensional laser imaging,and star-to-ground laser ranging,due to its small volume,high accuracy,and fast response speed.The echo time of the time-of-flight method is the focus of this technology.The situation of"strong background noise and weak signal light intensity"is that the laser ranging technology needs to face.On one hand,the background noise is too strong relative to the signal light and the signal-to-noise ratio is low,which makes signal processing difficult.On the other hand,the avalanche photon diode(APD)unit with Geiger mode is prone to channel saturation or channel blockage under strong background noise.This paper derives and discusses in detail the spatial three-dimensional convolutional neural network signal processing model,which combines the photon counting method with the convolutional neural network method.The simulation verifies that this algorithm can effectively identify the weak signal light from the strong background light.Methods A theoretical model is established via theoretical derivation and subsequently it is verified via simulation.Firstly,different from the previous laser ranging signal processing that only considers the probability distribution of the signal response in time domain and presents the Poisson distribution,this article adds a discussion of the probability distribution in spatial domain on this basis.We believes that the signal light and background light received by the receiving lens barrel used for laser ranging have spatial distribution differences.Therefore,in the simulation,the signal light is set as the far-field spot that obeys the two-dimensional Gaussian-like distribution,and the background noise is set to be evenly distributed in spatial domain.Then,this article simulates the insertion of short signal light into long background noise,and obtains the original signal used in this algorithm with the Geiger

关 键 词：测量 盖格模式 脉冲激光测距 阵列探测 光子计数 卷积神经网络 信号处理 

分 类 号：TN958.98[电子电信—信号与信息处理]