Stealth Radar 3s Signal Parameter Estimation And Recognition Algorithm

In order to enhance the surviving capability in modern warfare, complex modulated and varied parameter signals are adopted, such as Hybrid Spread Spectrum Stretch(3S) radar signal, which is also used in the pulse frequency modulation and phase encoding, making the traditional interception systems lose their advantages. How to effectively recognize and estimate new Low Probability of Intercept (LPI) stealth radar signals is important in military areas.In this dissertation, the recognition and parameter estimation of Continuous Peseudo-Random Bi-phase Code-Linear Frequency Modulation(PRBC-LFM) multiplicative and convolution signal in 3S radar signals are studied. The results obtained from this dissertation are some references to increasing probability of interception for electronic reconnaissance system in complex electromagnetic environment. The main contributions are as follows:1. Based on signal generation mechanism, the models of multiplicative and convolution signals in 3S radar signals are established. The properties of time domain, frequency domain, time-frequency domain, spectral correlation domain and ambiguity domain for these signals are analyzed.2. For the two kinds of signals, recognition algorithms based on establishing frequency model and calculating the moment coefficient of kurtosis in frequency domain are proposed.3. When the LFM signal, the Bi-phase Code signal, the multiplicative signal and the convolution signal coexist, the tree discriminator method is studied to separating them after feature extraction.4. For multiplicative signal, two approaches are adopted to estimate parameters. One is based on square transform-delay-and-multiply(DM), the other is based on square transform-cyclic autocorrelation.5. For convolution signal, two approaches are adopted to estimate parameters. One is based on reverse-order conjugation convolution-fast dechirp, the other is based on spectral analysis-fast dechirp.