基于大规模阵列单光子雪崩二极管探测应用的编码方式研究  

Coding Based on Large⁃Scale SPAD Array Ranging Application

作　　者：潘庆愉 王超[1] 任嘉伟[1] 王大鹏 朱义君[1] Pan Qingyu;Wang Chao;Ren Jiawei;Wang Dapeng;Zhu Yijun(Information Systems Engineering College of PLA Strategic Support Force Information Engineering University,Zhengzhou 450000,Henan,China)

机构地区：[1]战略支援部队信息工程大学信息系统工程学院,河南郑州450000

出　　处：《中国激光》2023年第19期125-133,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(62071489,61901524);国家重点研发计划(2018YFB1801963)。

摘　　要：单光子雪崩二极管(SPAD)阵列探测器常被用作空间远距离目标的测距和三维成像。为快速获取光子数据,SPAD阵列探测系统一般选用高重复频率的探测体制。目前,主要采用随机序列对脉冲进行编码的方法来抑制高重复频率引起的距离模糊效应。为了在接收端对阵列像素实现有效区分,而且各周期内的编码波形不相互串扰,需要数量庞大且可保持相互正交的随机编码序列。本文提出了使用混沌序列对SPAD阵列进行编码的思路,并通过分析Lyapunov指数的值域变化,提出了复合型Logistic序列的优化编码方案。为确保阵元间的互扰不会影响最终的探测效果,提出了峰值旁瓣差(PSLD)的概念,并对阵列间互相关积累的影响进行了定量分析。依据峰值旁瓣差对生成的混沌序列进行了筛选,以保证其能够满足所需阵列规模的抗互扰要求。最后给出了具体的编码流程。Objective Single-Photon Avalanche Diode(SPAD)array detectors are commonly used for the ranging and three-dimensional imaging of long-range targets in space.In the application of detection with SPAD devices,the detection system generally selects a high-repetition-frequency detection system to obtain photon data quickly.Currently,random sequence coding is primarily used to suppress the range ambiguity effect caused by a high repetition frequency.To meet the requirements of fast target detection under the conditions of a long distance and large field of view,more complete target information must be obtained through multiple parallel SPAD detection pixels.For an SPAD array with a large array structure,any photon signal reaching the receiver surface can cause an equivalent photocurrent response.The return signal received by a certain element may originate from several different transmission signals,which may affect the array detection results.To effectively distinguish the array pixels at the receiver,the coding waveforms in each period should not interfere with each other,and numerous random coding sequences are required to be orthogonal to each other.Because of factors,such as waveform duration and hardware system accuracy,the coding sequences in the actual system have a certain degree of correlation.In addition,the optical signal is non-negative,and the power is only superimposed but not offset.The cross-correlation responses among the array elements accumulate,which interferes with the identification of correlation peaks,resulting in false detection alarms and result misjudgment.Therefore,identifying a random sequence with a strong anti-interference ability to encode an SPAD array is required for highly accurate detection.Methods The basic principle of using random coding to solve the range ambiguity problem in a single-photon detection system is introduced,and the coding structure and correlation characteristics of pseudo-random,true random,and chaotic sequences are compared and analyzed.Owing to the fixed coding

关 键 词：探测器 单光子探测阵列 混沌序列 峰值旁瓣差 级联编码 

分 类 号：O436[机械工程—光学工程]