Research Of UAV Tracking Target Location Technology On BDS

UAV(Unmanned aerial vehicle)tracking reconnaissance has received high attention from many countries for its advantages such as high rea l-time performance,high resolution,low cost,no casualties,easy to use,etc.The target location accuracy is the most important indicator of UAV reconnaissance system,which occupies an important place in UAV design.The realization of the function of positioning involves several aspects including the position,the attitude,the azimuth and the elevation of flight platform.Besides,there are the distance from photoelectric platform to target,all kinds of coordinate transformation,and so on.The target location errors of UAV aerial are mainly summarized as follows: positioning error,attitude angle error,laser ranging error and measuring angle error of the optoelectronic stabilization platform,etc.The Ground tracking Station,Global Navigation Satell ite System(GNSS),Inertial Navigation System(INS)and Integrated Navigation System can be used for measuring the UAV aerial positioning.Here we analyze the Global Navigation Satellite System.Traditional UAV navigation is through the Global Positioning System(GPS)and Inertial Navigation System(INS)to obtain the position information and attitude angle of flight platform.GPS is a navigation system of the United States,and completely controlled by the United States.In wartime,the situation is grim,The Global Navigation Satellite System plays a crucial role in the war,if only rely on the GPS navigation system of the United States,must be controlled everywhere,if there is a sudden change in the wartime,it will have an immeasurable effect.China's own development of the “COMPASS II” network will be successful,accuracy of measurement can be comparable with GPS.Then BD will cover the global and serve the world.Using the triple BD navigation signal through carrier phase measurement technology can realizes the high positioning accuracy,which will have a great help for improving of the UAV aerial positioning accuracy.In this paper,we mainly study the impact of UAV aerial positioning error and platform attitude angle error on target location accuracy.The impact of attitude determination accuracy of Multi-BD receivers on target localization accuracy is researched.Then,the model of coordinate transformation is established.The method of the attitude measurement of BDS instead of INS(inertial navigation system)is analyzed,which can eliminate the error caused by INS due to time accumulation.In addition,the traditional approach of single target location is difficult to adapt the situation of the modern battlefield in changeable and large number of targets.To solve this problem,a multi-object real-time location method is proposed,and RLS filtering is used to improve the target localization accuracy.The experimental results show that the target location error is mainly related with the measurement error of the aircraft attitude angle,the system error of BD,the azimuth angle of the photoelectric platform and the measurement error of the high and low angle.In addition,it is related with the oblique distance between the platform and the target.Moreover,it can be concluded as follows: the high a nd low angle of optoelectronic platform is smaller when the flying height is higher.The positioning error is larger when slant distance is bigger.The attitude measurement accuracy is greater when the baseline is longer.The error of rolling angle is the minimum when the baseline is vertical.The proposed method of multi-target real-time location can effectively enhance the real-time performance of UAV and improve the location accuracy and reconnaissance efficiency.