The Research Of Passive Ranging Technology Of Target Based On Image Chain

In modern military campaign, it plays a great role for precision positioning and tracking of object to attack the target efficiently in a short time, and the ranging of object. Especially the real time and precision measurement of the distance to the target is the most important step.There are two ways for distance ranging: active ranging and passive ranging. Traditional active ranging uses laser as a tool. In despite of its real time and high precision, it has to emit high power laser pulse which is prone to be exposed to enemies, that is a fatal disadvantage, also it needs complex equipment. So this method goes against the trend of lightness and convenience of weapons. As a result, passive ranging becomes the main way to measure the distance to target in modern wars.This paper is brought forward to realize the real time and precision passive ranging of flying object in air on target tracking and detecting system on ground then supply parameters for attacking weapons. Passive ranging has characteristics of high precision and real time, especially for its good concealment it is applies widely in military. There are single station passive ranging and multi station passive ranging sorted by the numbers of stations.Based on the analysis of kinds of methods of passive ranging, a new method combining binocular and motion was advanced. The distance is computed by the disparity which is got by image matching in different pictures. At first binocular passive ranging is tested, and then multi cameras are used to form image data chain to reduce error. Dual DSP plus FPGA hardware system was designed containing schematic circuit and PCB also part of FPGA program was designed. Correlation tracking algorithm was improved using image matching.There are five parts in the paper, the first chapter is exordium, and this chapter introduces the problem background and source, the development level of passive ranging. The second chapter depicts the principle and algorithm of random position multi station passive ranging combining binocular and motion. The third chapter introduces the structure of system hardware and the working processing. The fourth chapter contains FPGA programs of image transmission, transformation and display. The fifth chapter on basis of improvement of image tracking algorithm, a method for correlation image matching was put forward. And the last part is conclusion portion summarizing and prospecting for the whole paper.