Research Of Data Processing Technology In Photon Counting LIDAR Systems Under Movable Conditions

Photon counting LIDAR system is a kind of active photoelectric detection technology based on the detection of weak photon signals, able to respond to every single photon in echo wave signals and solve the contradiction between the limited system resources and the overall performance of LIDAR system effectively. With the development of laser ranging technology and the deepening of its application, it has become a key application field to measure the 3D information of topography, providing high accuracy surface information for land observation and city modeling by means of laser ranging. More and more attention has been paid to measurement of distance information of targets in moving conditions such as airborne laser ranging. Besides, as an important function of photon counting laser radar systems, acquisition of ground target information, especially detection of ground moving targets, has important applications in the fields like monitoring ground traffic flow. As a result, it is helpful to realize the fast and effective extraction of the distance information of moving targets and improve the detection efficiency of moving targets to study the data processing technology of photon counting LIDAR systems under movable conditions.Application background and current development situation of photon counting LIDAR system are introduced in this paper. Besides, detection theory of photon counting LIDAR under movable conditions is studied. In addition, theoretical issues related to the data processing technology of photon counting laser radar system such as statistical features and detection probability of echo wave signals are analyzed. Aiming at laser ranging in moving conditions, motion model of target and detection model of system are established. Moreover, simulated echo wave sequences containing both target echo wave signals and noise echo wave signals in accordance to the law of statistical distribution are produced based on Matlab. Also, traditional data processing algorithms of photon counting laser radar are studied. Furthermore, combined with the characteristics of photon counting laser ranging in moving conditions, a developed point cloud processing algorithm based on division of range bins and an algorithm based on correlation matching of the movement of target are brought up. Noise signals that distribute randomly in the entire detection space are filtered effectively and motion track of the target is obtained after applying these algorithms to the simulation echo wave signals and using ranging point cloud data acquired in real experimental environment to validate the performance of the algorithms. Compared with traditional data processing algorithms which are used mainly in the field of immobile target ranging through photon counting LIDAR system, the two algorithms have better adaptability to the point cloud data processing of photon counting laser ranging under movable conditions and can avoid the disadvantage of being too dependent on accurate prediction of target distance information. Finally, devices needed for the realization of point cloud data processing algorithm are selected according to both the data processing performance requirements and features of the algorithm, providing a meaningful reference for subsequent algorithm realization and further study of data processing technology in photon counting LIDAR system.