Deinterleaving Of Radar Signals And Analyzing Fine Features Of Intra-pulse Signals

In order to fit for the Electronic Warfare environment of today and future, Electronic Support Measure and Electronic Intelligence systems must have the ability to analyze rapidly and dispose all kinds of radar signals in real time or near real time. Deinterleaving of radar signal and analyzing fine features of intra-pulse signal is a pivotal technique and difficult problem in these Electronic Counter Measure (ECM) fields all the time.The main conventional methods of deinterleaving radar signal are based on Pulse Repetition Interval (PRI) almost, including so-called benchmack algorithm, cumulative difference histogram, sequential difference histogram and PRI transform. This thesis introduces theories and realizing flows of these methods in detail, and analyzes their advantages and disadvantages by simulating experiments. Through modifying several flaws of PRI transform, the thesis brings forward a modified PRI transform algorithm. The modified algorithm has high estimating precision for PRI, and solves the problem of deinterleaving dither PRI radar pulses effectively. The thesis introduces several advanced deinterleaving algorithms, too. The first one is the deinterleaving method for irregular radar signals with Resnick model; the second one is the deinterleaving method for radar signals with dithering PRI; and the third one is the deinterleaving method based on pulse repetition frequency. All of these algorithms depend on advanced signal processing methods, and they provide new ways for deinterleaving of radar signals. Furthermore, the thesis researches the problems of synthetic analysis in deinterleaving field, too, and brings forward an effective method to pick up pulses.In the face of more and more complex radar signal environment, ECM systems of new generation not only use the five conventional parameters, i.e. direction of arrival, radio frequency, time of arrival, width of pulse and amplitude of pulse, to deinterleave pulses, but also have the ability to analyse and pick up radar signals' intra-pulse fine features. At present, the general methods to research intra-pulse fine features include autocorrelation method in time field, inverse spectrum technique in frequency field, detecting at zero point in modulation field, and so on. From the points of theory, realizing flow, and automatic recognition technique, the thesis analyses these methods' traits in detail, then brings forward a full scheme to pick up intra-pulse's fine features. Furthermore, a new method is brought forward in the thesis. The method measures signal's instantaneous frequency through differentiating instantaneous phase, and it has a fine effect in modulation type recognizing field.As an advanced method of time-frequency analysis, wavelet transform can get high resolution in both time field and frequency field. The last chapter of this thesis...