Chaotic Signals with Weak-Structure Used for High Resolution Radar Imaging

Recently, signals generated via chaotic maps for radar imaging have been studied. Chaotic signals are easy to be generated and applied, but not all chaos-based signals are suited for high resolution radar imaging. The autocorrelation and ambiguity functions of many chaos-base modulated signals are poor, so they aren't suited for radar imaging. Up to now, there has no reference to summarize which kinds of chaotic maps are fitted for high resolution radar imaging, or why they have these radar imaging properties. In this paper, we presented that chaotic maps with weak-structure, which have bigger Lyapunov exponent and bigger extending velocity, are similar to noise, and have good properties for high resolution radar imaging. We presented some chaotic maps with weak-structure, too. By simulating, It was demonstrated that, after many kinds of modulations, the autocorrelation and ambiguity functions of modulated signals generated via chaotic maps with weak-structure have good characteristic and these chaotic signals are suited for high resolution radar imaging, while those chaotic signals without weak-structure aren't.