In order to verify the space borne three dimensional lidar imaging technology,a ground scaled model lidar prototype is designed based on high repetition rate photon counting technique,and it has the characteristics of sub-field,non-scanning and multi-channel.The system uses two high repetition frequency,micro-pulse lasers(repetition frequency 10 kHz,single pulse energy 60 μJ),and the multi-channel detection is achieved based on large spot multi-sub-array photon detection.Besides,the time interval and time correlation statistics for single photon response time are measured by using FPGA based time coincidence count signal processing technology.Then the target distance can be obtained according to the target response time consistency and randomness of the noise response.In the field experiment,the distance of the buildings that is more than 10 km was measured,and the ranging accuracy is better than 0.3 m,detection probability is more than 99%,and the influences of different atmospheric visibilities on ranging are compared.The system validates the feasibility of multi-sub field of view of space born lidar and fiber optic focal plane receiving scheme,and proves the ranging accuracy and adaptability of lidar based on photon counting.%为了验证星载激光三维成像雷达技术,设计研制了一种基于高重频光子计数体制的分视场、无扫描的多通道激光雷达地面原理样机.系统采用两路高重频、微脉冲激光器输出,结合大光斑多元细分阵列光子探测方式实现多通道探测,并采取基于FPGA的时间相关符合计数信号处理技术,对单光子响应时刻进行时间间隔测量和时间相关统计,根据目标响应发生时机一致性和噪声响应的随机性提取目标距离信息.在外场试验中对水平距离大于10 km的楼宇目标进行了有效地测量,单通道的距离测量精度优于0.3 m,探测概率超过99%,并对比不同大气能见度下对测距的影响.该系统验证了星载激光雷达大光斑多元细分、光纤拼接焦面接收方案的可能性,并验证光子计数体制激光雷达测距精度及适应性.
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