Intra-pulse Modulation Recognition And Parameter Extraction Based On Time-Frequency Distribution

Reconnaissance and jamming to enemy radar plays a key role in the electronic countermeasure,both of which will fail without the analysis of intercepted radar signal.In processing intercepted signal,the algorithm for analyzing the intra-pulse of radar signal is a very important issue.This paper mainly deals with the algorithm for intra-pulse modulation recognition and intra-pulse parameter extraction of radar signal.Firstly,this paper gives a brief introduction to the signal processing section of radar reconnaissance system.Three different time-frequency distributions,i.e.ambiguity function,Wigner-Ville distribution and MH-H transformation,are presented,based on which three different intra-pulse modulation recognitions are then proposed.Moreover key and detailed discussions of and research on these three algorithms are given,meanwhile the recognizing principles and detailed processes are also presented.These algorithms can automatically recognize six types of modulation signal,which includes monopulse,LFM,BPSK,QPSK,2FSK and 4FSK.The recognition performances of all these algorithms on mentioned signals are discussed.On the other hand,this paper presents intra-pulse parameter extraction algorithms according to different types of signal,which are experimented with Monte Carlo simulation additionally.The performances are compared based on the result analysis.Finally,the conclusion,which the algorithm for analyzing the intra-pulse based on time-frequency distribution has better performance but needs more calculation than traditional one,is verified.