Research On MIMO Radar Waveform Design Based On Chaotic Signal

The multiple-input multiple-output(MIMO)radar has more advantages than the conventional phased array radar.Recently,it has attracted the attention of many scholars.Since the waveforms transmitted of each radar array unit are orthogonal to each other,the orthogonal performance of the designed waveform should be considered.Chaotic signals as pseudo-random signals are controllable and easily generated in large quantities.Therefore,researching the radar waveform design based on chaotic signals can easily avoid the complicated optimization process in the optimization algorithm and make the analysis of the transmission waveform more flexible and convenient.So,the paper focus on the chaotic signal waveform design.My main research work is:1.Analyzed and explained the working principles and the requirements of waveform design of MIMO radars.Introduced the theory of chaos signals.Analyzed four one-dimensional discrete chaotic maps of logistic,tent,bernulli,and quadratic,and three-dimensional continuous-time chaotic system of lorenz,rossler,and chua.Simulated and analyzed several characteristics of chaotic signal systems.2.Three kinds of discrete chaotic modulation signals are analyzed.They are discrete chaos frequency modulation signals,discrete chaos phase modulation signals and discrete chaos frequency-phase composite modulation signals.Simulated and analyzed the formation mechanism,the quantification method and the waveform performance of these three types of signals.The research shows that the correlation of modulated discrete chaotic signal systems have been optimized.The power spectrum is flat.It is really a good radar signal.3.After discretization,the continuous chaotic system was applyed to design the radar waveform.Tha paper used lorenz system as an example to perform the performance of frequency modulation,phase modulation,and complex modulation respectively.Compared the correlation,power spectrum,and ambiguity function of modulated continuous chaotic system.Researched the performance of the waveform,and the relationship between the length of the sequence and it's correlation.The relationship between the length of the sequence and the correlation was obtained.4.The innovation of this paper is the design of discrete and continuous chaotic signal waveforms through the combination of chaos and the introduction the polyphase coding.It improved the complexity of the waveform and optimzed the correlation.It makes the waveform library is more abundant.For example,the number of phase states can be set autonomously by multi-time coding,and the duration of each phase is different.New waveforms obtained by chaotic sequence quantized modulation of multi-time coding will have great research value in the future.