Researches On Technology Of Clutter Suppression And Inter-frame Correlation Processing In Some Radar

Clutter suppression technology is an important method to detect target under the clutter background. It is a problem worth studying how to detect the small and slow target of the sea surface effectively.In this paper, the researches on the design of the adaptive filter and the inter-frame correlation processing technology are carried out. The main work is summarized as follows:First, research on the design methods of moving target indication(MTI) filter. Starting from the analysis of the characteristics of the clutter, the traditional delay line canceller filter and the optimal design of the MTI filter are introduced. The design method of three kinds of MTI filters, which are the prediction error method, the feature vector method and the zero point distribution method, are emphatically analyzed. Then the time-varying cascaded filter design method under the variable T mode is introduced. In order to obtain a better MTI filter passband performance, the method of genetic algorithm is used to analyze the method of optimize stagged code. In addition, the estimation method of three kinds of clutter doppler frequency is introduced in detail, and the simulation analysis of these methods is carried out. Simulation results show: When the clutter is strong, zero point distribution method should be used to design the MTI filter. When the clutter is weak, the MTI filter can be designed by using the prediction error method or the feature vector method. Meanwhile, the linear phase method can be used to estimate the doppler frequency under the variable T mode, and the correlation function method can be used to estimate the doppler frequency under the T mode. Finally, the measurement data is processed.Second, researches on the design methods of moving target detection(MTD) filter and slow target detection. Design methods of several kinds of MTD filters are introduced in detail, including MTI cascade FFT filter group, point doppler filter group and equal interval doppler filter group. Start from the basic principle of clutter map and two kinds of methods to establish the clutter map, two kinds of slow target detection methods based on the super clutter detection and the zero-frequency restrain are introduced, and the simulation analysis is carried out. The simulation results show that the effectiveness of the two methods.Third, research on the inter-frame correlation processing technology. Firstly, two methods of the radar echo data accumulation are introduced, and the simulation analysis is carried out. Then the target echo model of the inter-frame correlation processing is analyzed in detail. On the basis of the above, the general processing flow of the inter- frame correlation processing is given. The five modules of the processing flow, including the pulse selection, pulse compression, MTD processing, comepensation for the number of targets across the distance unit and the noncoherent accumulation of inter-frame are described in detail, and the simulation analysis is carried out. Finally, combining with the measured data processing, the above process is verified. The results show that the effectiveness of the process.