Research And Implementation On DSP Of Radar Signal Sorting

The electronic countermeasure environment has become more and more complicated along with the rapid development of radar system.The complicated signal environment including more complex radar signal modulation,faster parametric variation,and more types of application is challenging for radar signal processing.As part of the radar signal processing,radar signal sorting needs to be improved continuously.In this paper,the traditional signal sorting algorithm based on PRI radar signal sorting and multi parameter joint sorting was investigated to provide a theoretical basis for the following study.The paper proposed the two-level separation structure including pre-sorting and main-sorting.Pre-sorting employed improved K-means algorithm to process Direction of Arrival(DOA)and Carrier Frequency(CF)as two stages.The main-sorting was carried out by de-interleaving via combination of improved PRI transform algorithm and dual-threshold sequence search.The Emitter Description Word(EDW)was given by parameter estimation and pulse interval identification.A new method of singal sorting based on time difference was proposed to recognize the complicated pulse interval modulation and hybrid pulse repetition interval radar.The time Difference of Arrival was extracted by multi-station observation and deinterleaved with other Pulse Description Words(PDW),followed by sorting with the Multi-layer Perceptron neutral network and Random-Forest classifier.The method was verified by simulation experiment.According to the previous theoretical research,the radar signal sorting is achieved on the Digital Signal Processor(DSP)of TMS320C6678 with improved K-means algorithm and PRI estimation algorithm.The algorithm with the FPGA+DSP architecture completed data interaction,logic control,algorithm implementation and other functions.Finally,the whole system was tested to meet the requirements of the index and complete the excepted functions.The system can recognize various types of signal including constant,jitter,stagger,sliding,and frequency hopping signal.The runtime of module was under 0.32s.