机载激光雷达是近年来比较热门的主动式三维数据采集技术，相比传统测量方法、航空摄影测量技术、微波雷达等具有采集速度快，数据量大，精度高等优点，引起了人们的广泛关注。但目前，国内技术应用严重依赖国外成熟系统产品进口，技术研发相对滞后。本文根据多方调研，对国内生产机载激光雷达系统的可行性和相关技术难点作了大量的研究，并提出了一套初步的设计方案。 根据调研，国内IMU/DGPS定位导航产品精度达不到机载雷达系统的使用要求，因此本文的设计思想为采购一整套的进口POS产品来确定飞行平台的位置及姿态，核心内容为主要传感器——机载激光扫描仪的设计。 设计系统采用低空遥感平台，飞行高度300~1000m，不超过1500m，巡航速度160~220km/h，扫描带宽300~800m。采用美国Spectra-Physics（理波）公司NavigatorTM系列的一款激光器产品Navigator 1064-5作为探测光源，激光波长1064nm，每秒可产生20000~50000个数据点，经扩束镜准直后激光发散角0.55mrad。采用交流电机驱动正六面镜旋转扫描方式，使用最大扫描角±30°，视场角30°~60°可调。设计扫描频率45~60Hz，激光脚点间距小于1m。设置两个探测器，PIN管用于主波探测，APD管用作回波探测，由FPGA完成时间间隔测量。各种传感器获取的信息，包括电机转速、回波强度、其他设备监测信息等也被FPGA数字电路高速采集，通过接口传输给ARM嵌入式系统。ARM是扫描仪的主控制器，通过键盘或上位机获取控制指令，再由FPGA执行具体的测量操作。 本文还就集成系统各个组件获取的距离、角度、坐标、姿态等信息进行组合，由极坐标原理得到了激光点云定位模型。并分析了设计系统的理论精度和影响精度的各种因素，最后对系统设计中发现的问题进行总结，分析了国内产品研发滞后的部分原因，肯定了该项技术的产品化前景。

As a proactive detection technology, Light Detection and Ranging, also known as Airborne Lidar, is more popular in recent years in the three-dimensional data acquisition. Compared to regular measuring methods, the aerial photogrammetry technology and microwave radar, Airborne Lidar systems are faster in speed, higher precision in large amounts of data acquising. Therefore, Light Detection and Ranging technology has aroused widespread concern. But the situation of domestic technical researches and development present is relatively backward. The domestic market mainly relys on the applications of importing commercial system products from the overseas. According to various researches, this paper made a lot of work on the feasibility of the domestic production of Airborne Lidar systems as well as the technical difficulties in program designing, and proposed a preliminary design scheme finally. Based on the market investigation and study, it is found that the accuracy of the domestic IMU/DGPS positioning and navigation system products does not meet the needs of the requirements of Airborne Lidar systems. Therefore, the design philosophy of this paper is to design an airborne laser scanner——the main sensor of the system independently and to purchase a set of POS products, which can provide the flying platform the position coordinates and posture information, to integrate a set of radar system at last. The design of the airborne laser scanner is the core content of this study. The designed system is placed on the low-altitude remote sensing platform, relative flying height:300 to 1000m approximately, no more than 1500m in principle, to cruise at the speed of 160 to 220 km/h. The scan bandwidth is 300 to 800m. Using Navigator 1064-5, one of the Navigator TM series laser products as the system light source, which is manufactured by United States Spectra-Physics (Newport Corporation) company. The laser scanner may send out 20000 to 50000 bunches of lasers each second, with the wave length of 1064nm. The laser beam divergence angle is 0.55mrad after the collimation of the scattering beam mirror. The cube mirror scanning mode is applied. The maximum scanning angle is ± 30 ° and field of view angle 30 ° to 60° adjustable. 45 to 60 scan lines are received per second, which can be said to be the scanning frequency 45 to 60Hz. The interval between the two adjacent scans is less than 1m. Two detectors are introduced, one PIN detector works as the primary wave detector, and the other APD works for echo detecting. The time interval between the primary wave and the echo is measured by the FPGA digital logic circuits. At the same time FPGA also can gain the information from anther sensors, such as the rotational speed of the electrical machinery, the echo-strength, monitors information, and so on. FPGA transmits the information to the ARM embedded system through an interface. ARM is the main controller of the scanner, who is allowed to access control directives through a keyboard or host computers. FPGA is responsible to carry out these specific measurement operations. The paper also combines distances, angles, coordinates and attitude obtained by various components in the system for a model to locate laser points cloud according to the polar-coordinate method. Moreover, the theory precision of the designed system is derived and each kind of factors who influence precision is analyzed. At the end of the paper, the problems found in system designing are summarized. And several reasons for the lag of the domestic products research and development have been analyzed. It is certern that mature products homemade under this technology will appear in the near future.