基于近红外单元单光子雪崩二极管的相干测速实验分析  

Experimental Analysis of Coherent Velocity Measurement Based on Near-infrared Single-element SPAD Detector

作　　者：李彬 王晓芳 康岩 岳亚洲[1] 李薇薇 张艺馨 雷宏杰[1] 张同意[2,3] LI Bin;WANG Xiaofang;KANG Yan;YUE Yazhou;LI Weiwei;ZHANG Yixin;LEI Hongjie;ZHANG Tongyi(Xi′an Flight Automatic Control Research Institute,Aviation Industry Corporation of China,Xi′an 710065,China;State Key Laboratory of Transient Optics and Photonics,Xi′an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi′an 710119,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国航空工业集团公司西安飞行自动控制研究所,西安710065 [2]中国科学院西安光学精密机械研究所瞬态光学与光子技术国家重点实验室,西安710119 [3]中国科学院大学,北京100049

出　　处：《光子学报》2024年第1期202-211,共10页Acta Photonica Sinica

基　　金：国家自然科学基金(Nos.62001473,62171443);陕西省重点研发计划(No.2022GY‒009);西安市青年人才托举计划(No.095920211305)。

摘　　要：为分析死时间、暗计数等因素对单光子相干测速性能的影响,搭建了基于近红外单元单光子雪崩二极管探测器的外差相干测速实验系统,实验分析了探测器暗计数率和信号探测光子计数率对多普勒信息重建的影响,以及由探测器死时间决定的饱和计数率限制下的最优信号探测光子计数率。在1μs探测器死时间、1 ms采集时间下,分别对1.8 kHz、52.4 kHz和194.4 kHz探测器暗计数率影响下的光子到达时间序列进行快速傅里叶变换,从频谱数据中提取拍频信号。实验结果表明,随着光子计数率的增加,相干拍频信号频谱信噪比逐渐增大而后趋于平稳,当接近饱和计数率时,在相干拍频信号频谱低频区域和拍频频率两侧出现了谐波分量,谐波频率间距与光子计数率数值基本相等,受谐波影响较小的最优光子计数率约为单光子探测器饱和计数率的90%。研究结果可为全光纤单光子多普勒测速雷达技术的发展和应用提供参考。Coherent lidar has advantages of suppressing background noise such as sunlight and detecting sensitivity close to shot noise limit.It is widely used in civil and defense fields such as wind detection,velocity measurement and military target detection.Coherent detection can be divided into heterodyne detection to extract frequency information and homodyne detection to extract phase information.For velocity measurement,heterodyne detection is usually used to extract the Doppler frequency shift of the echo laser from a moving target,and then the velocity of target is retrieved.Conventional heterodyne lidar adopt normal optical detectors,such as PIN detectors,which have limited detection sensitivity for a small number of echo photons.And generally,strong local oscillator laser power is required to suppress thermal and circuit noise,but excessive local oscillator is likely to generate excess shot noise.With the development of Single Photon Avalanche Diode(SPAD)detector with low circuit noise,it not only provides a way for the detection of a small number of echo photons,but also makes it possible to realize heterodyne detection with a weak local oscillator.Researchers have successively adopted InGaAs SPAD array detectors and superconducting nanowire single-photon detectors for near-infrared spectrum,single-element Si SPAD detectors and MPPC detectors for visible spectrum,but there have been few experimental research on heterodyne detection with single-element InGaAs SPAD detector.The heterodyne lidar based on near-infrared SPAD can be integrated in all-fiber structure with an operating wavelength of 1.5μm,which makes it more suitable for practical working platforms such as airborne.Although the count rate dynamic range of the single-element SPAD is not as good as that of the SPAD array,the current disadvantages of SPAD array,such as low pixel fill-factor,poor uniformity of pixel performance(e.g.,hot pixel),and slow speed of data readout,limit its performance to a certain extent.Besides,compared with superconducting na

关 键 词：相干探测 光子计数 外差探测 多普勒 测速 

分 类 号：TP79[自动化与计算机技术—检测技术与自动化装置]