| Now, there are two problems in Remote Sensing (RS) techniques: images can not be obtained in real time and it is very expensive to obtain by plane or satellite. Aiming at these situations, a miniature airborne optical RS system which consists of a Digital Camera (DC), a miniature robot plane(Unmanned Aerial Vehicle, UAV) and its' ground-based subsystem was presented on the basis of analyses of the applied experiences of UAVs abroad and home. In this paper, two type problems about this miniature RS system would be discussed: one was system integration, amelioration and flight planning; another was geometrical correction of images from this system.In the stage of system integrating, the applications of DC in aerial RS was analyzed, the conclusion was that the advanced models in actual digital cameras had been satisfied to most RS application. In technique rebuilding of system, discharge curve of Ni-MH battery was measured, and power supplies in UAV were improved. The security, adaptability and efficiency of miniature aerial RS systems could be improved obviously by microwave video transmission system and self-regulating blocking net in landing. As a pattern, the flow of flight planning of WuMing county in GuangXi province was introduced, it was good to the planning of similar RS flight. The flight experiments had proved that the miniature aerial RS system based on UAV would be the useful supplement of satellite RS and aerial photography. The advantages of this system are as follows: obvious flexibility, broad adaptability, rapid response, low cost and the ability of acquiring high-resolution images.Because UAV is smaller and lighter than normal plane, the miniature aerial RS system is easily effected by wind, its' stabilities of position and stance are not good. Because the load of UAV is so finite, the large professional aerial photogrammetry camera can not be installed. Considered as size, weight and price, the Charge Coupled Device (CCD) DC is the best choice for the UAV RS system. The factors mentioned above would bring lots of complicated geometrical distortion to the images from the UAV RS system. On the basis of analyzing roundly origins of RS image geometrical distortion and existing methods of geometrical correction, the route of geometrical correction for the images from theminiature UAV RS system was brought forward. This technical route was based on integrated CCD camera calibration and image registration by orthograph.CCD camera calibration was accomplished by vertical photograph on the wall of buildings. This method was aimed at the texture of existing figures on the wall, so it did not need use special instruments and array lots of reference points, it only needed some simple marks and measuring work to accomplish the photograph of base image. The problems of CCD camera calibration could be solved effectively and simply by the obtained image and mathematic model.By means of images processing of satellite, geometrical correction of images from UAV RS system was accomplished by polynomial. In the processing of images of WuMing in GuangXi province, a set of scan large-scale relief maps were used. By testing the corrected image map, the mean error of point position was 1 meter, the maximal error was 2 meters, length distortions on X and Y axis orientation were not more than 1% and angle distortion was almost not existing. As the basic image, large-scale relief maps were not good, with some disadvantages of accuracy and surface features. If a high-resolution satellite image could be used to registration as a basic map, the accuracy of corrected image map would be improved obviously.This study has proved that it was feasible that common DC and UAV were combined to construct a miniature aerial RS system. After geometrical correcting, the high-resolution RS images from the UAV RS system were as good as the images of satellite or aerial photogrammetry. The miniature UAV RS system is a new technique that could be used to quickly acquire images of small region with low-costs.
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