Tracking And Recognition Technologies Based On Target Glint Signature For Terminal Guidance Radar

Target glint is the main factor which influences tracking and guidance accuracy of terminal guidance radar. Researchers on radar precision guidance weapon pay much attention to suppress glint, improve angle measuring accuracy and improve guidance radar's tracking and guiding accuracy. On the other hand, it is well known from the glint generation mechanism that target line glint error is also a target signature and it contains plenty of target information. So it is valuable to use target glint to enhance the performance of target recognition by high resolution range profile. In this paper, the theory and some applicational technologies about target glint for terminal guidance radar in optical region, including glint simulation, glint suppressing, target tracking with glint, target recognition using glint, are discussed in detail. The main work is outlined as follows.In chapter 1, radar precision guidance and its critical technology are clarified. Then the current status of the study on target glint is introduced. At the end of this part, the main works of this paper are outlined.In chapter 2, the theories and technologies of suppressing glint and improving angle measuring accuracy for frequency agility radar are studied. Firstly, the feasibility of glint simulation using multiple-scattering-centers target model is studied. Based upon this model, the decorrelation performance for target echo amplitude as well as the decorrelation performance for target glint of frequency agility radar is studied and the decorrelation frequency condition is verified. Secondly, a study on glint suppressing algorithm is performed based on amplitude weighting. Peformance comparison under different integer power amplitude weighting is made and the optimization of square amplitude weighting is proved. A kind of noncoherent integration angle measuring method based on SAW (square amplitude weighting) is developed. Finally, a new monopulse radar angle measuring algorithm based on ABA (amplitude based angle) plus SAW processing is presented. This algorithm takes ABA processing instead of common monopulse radar angle extraction method, and use amplitude weighting to further process the measured angle data. The optimal region principle is presented for monopulse radar antenna design.In chapter 3, the angle measuring method for stepped frequency radar and target tracking with glint are studied. Firstly, a systematic study is performed on high resolution range separation profile for stepped-frequency radar. The range resolution, unambiguous rangeseparation and the accuracy of motion compensation are analyzed in detail. The principle for high resolution range separation profile angle measuring is clarified. Then three angle measuring algorithms based on high resolution range separation profile are developed under oversampling conditions. SLCE method (selecting the largest of cross entry) is proved to be optimal through computer simulation. Secondly, a study is performed on the application of particle filter for tracking with glint noise. Monte-Carlo simulation proves that the performance of particle filter is far superior to EKF for tracking with glint noise.In chapter 4, the application of target glint signature in high resolution radar target recognition is studied. Firstly, the concept of "distributed glint" is put forward; the expression of "distributed glint" is deduced. Secondly, a new target recognition algorithm based on range profile and distributed glint is developed. Finally, a practical target recognition algorithm based on wavelet decomposition and BP neural networks is developed. Computer simulation verifies the performance of this algorithm.In chapter 5, all the work in this paper is summarized and related conclusions are presented, together with further research to be done.