Research Of Real-time Analysis And Processing Technique Of Radar Signal Intra-pulse Feature

The analysis and processing technique of radar signal intra-pulse feature plays a more and more important role in the passive radar system.This paper researches lots of radar signal intra-pulse feature’s analysis methods based on time domain and time-frequency domain,analyzes the advantages and disadvantages of these methods by simulation.Then it proposes a system method based on cyclic spectrum correlation combined with wavelet transform.In this paper we put the analysis and processing technique of radar signal intra-pulse feature in use on the platform of VPX framework and Power PC processor,and then improve part of real-time performance.The research work includes software simulation and hardware work,which can be described as follows.1).The analysis methods of radar signal intra-pulse feature on time domain are introduced.Firstly this paper analyzes the principle of instant autocorrelation,phase differencing and autocorrelation function for first differencing,then it makes a conclusion on the performance of these methods by simulation.2).The analysis methods of radar signal intra-pulse feature on time-frequency domain are introduced.Firstly this paper analyzes the STFT and wavelet transform algorithm.Secondly it proposes a system method based on cyclic spectrum correlation combined with wavelet transform to deal with the situation where the identification’s accuracy rate and parameters’ estimation are required to be better and PDW is required to be more comprehensive.The steps of this method are introduced in detail and the conclusion is made by simulation.3).The VPX standard and Power PC processor are studied.The real-time flushbonading system of VxWorks and the mode of cross developing are discussed,which makes a necessary preparation for the use of the analysis and processing technique of intra-pulse feature on the hardware platform.4).The analysis and processing technique of radar signal intra-pulse feature is put in useand partly improved on the platform of Power PC processor.Firstly the total tasks of four Power PC CPUs are designed.Secondly the intra-pulse modulation’s identification and parameters’ estimation modules are designed by the comprehensive usage of the analysis methods of radar signal intra-pulse feature,then the performance is tested with the process of actual measured intermediate frequency signals.Thirdly the element factors that affect the real-time performance are discussed,the improvement is made by the methods of lookup table and so on.The conclusion is made by the comparison of processed results before and after the improvement.At last another improved method is discussed,which analyzes some certain intra-pulse feature after brief PDW calculation and classification to make the system’s process faster.The analysis and process of actual measured data is given to make a conclusion.