| Passive radar contains no transmitter, uses extra illumination sources for target detection and tracking. Thus, it's undetectable to surveillance receivers using conventional radio direction finding techniques. In a military scenario, it can immune to the effects of deliberate directional jamming/interference and anti-radiation missiles attack. It requires no spectrum allocation and has no environmental impact. It is more portable and less expensive, and also has no coverage problems. So passive radar plays an important role in modern electronic batterfield, and it's also the hot research topic in radar area recently. In this thesis, WiMAX signal is firstly used as illumination source for passive radar application. Researches on feasibal analysis, system design and implementation, applications in movition target detection are conducted in detail.Firstly, performance of WiMAX passive radar is predicted. Components of clutters are analyzed based on the bistatic radar equation. Coherent integration gain as well as bistatic radar cross section are considered to modify the radar equation. Performance of WiMAX passive radar is predicted according to the mofied radar equation to provide the theoretic foundation for the passive radar design.Secondly, a MIMO-OFDM testbed is designed and realized according to the fixed WiMAX specification. The parameters can be changed freely, which makes the possibility of WiMAX passive radar from theory to realization.Thirdly, WiMAX signal waveform is analyzed. The WiMAX signal waveform parameters are calculated. Both fixed WiMAX signal and mobile WiMAX signal ambiguity functions are analyzed, and the effect of WiMAX signal physical layer parameters modification on the ambiguity function is concluded. The waveform calculation and the ambiguity function analysis results domenstrate that, WiMAX signal has a'bed of nail'ambiguity function. Fortunately, ambiguities have no effect on moving target detection, and the WiMAX signal will outperform other illumination sources in range resolution and coverage scheme.At last, we propose a simplified WiMAX passive radar system architecture, design and realize a world's first WiMAX passive radar system, and then apply it to the moving target detection. An effective least square based adaptive FIR direct path interference cancellation algorithm is proposed, and the improved one, multi-dimention least square base adaptive direct path and clutter interferences cancellation algorithm is also proposed to cancel the interference from both static stuff and the low speed moving stuff. The delay range-Doppler mathed filter 2D moving target detection algorithm is also realized. Indoor fixed WiMAX based and outdoor mobile WiMAX based moving target detection experiments are successfully conducted. The experimental results show that the WiMAX passive radar system can track the moving target accurately, which demonstrates that the system designed and the algorithm proposed can work effectively.A word in all, this thesis demonstrates the feasibility of WiMAX signal as passive radar illumination source from both theoretic and practical aspects. It also shows the superiority of WiMAX signal as the passive radar illumination source. All the results help WiMAX passive radar to be developed for practical or commercial use.
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