High Resolution Radar Target Recognition Method Based On Scattering Center Model

The wide band radar target recognition method can be classified into templates-based method and model-based method. The model-based recognition method has the advantages of small memory consumption, being on line, good flexibility and adaptable to extended operating conditions.The paper focuses on the research of wide band radar target recognition based on the global scattering center model. Two feasible recognition methods, which are retrieved profile-based method and the scattering centers matching method, are proposed using the 1D scattering center characteristics which is projected by the global scattering center model. Using the 2D scattering center characteristics projected by the global scattering center model, this paper transplants the 2D points matching method in computer vision field into the model-based radar recognition, and employs the combination of deterministic annealing and softassign optimization techniques to accomplish the target recognition by 2D points matching method. Specifically, more details are arranged as follows:Chapter 1 introduces the development status of the model-based radar target recognition and its significance.Chapter 2 introduces firstly the concept of scattering center of the wide band radar targets in optical region and some common parameter estimation methods, and then introduces briefly the reconstructing methodology of global scattering center model, at last, the measured data and the global scattering center model data used in this dissertation is introduced.In chapter 3, two profile recognition methods named retrieved profile-based method and the scattering centers matching method based on global scattering center model are proposed. The target profiles are retrieved using the scattering center's position information projected from the scattering center model and the amplitude information, the recognition based on retrieving profiles method is implemented. The scattering center characteristics are extracted from the target echo by parameters estimated method, and then a scattering center matching method based on amplitude weighting is proposed using the recognition thought of matching scattering center characteristics, which are verified by simulation tests using dark-room measured data and the electromagnetic computing data with scale models.Chapter 4 focuses on 2D scattering center matching method based on global scattering center model. The 2D points matching method from computer vision field is transplanted into the model-based radar target recognition using 2D characteristics, the matching problems of 2D scattering center can be treated as problems of minimum value of functions which restricted by inequations. By using the method of slack variables, inequation restriction can be transformed to equation restriction. Similarly, by using the method of Lagrange multipliers method, target function problems can be transformed to unrestricted problems. The combination of deterministic annealing and softassign optimization techniques is used to achieve 2D scattering center match, which is verified by simulation tests.Chapter 5 provides a systematic conclusion together with some discussions on further work.