中文摘要：

利用Wi Fi（Wireless Fidelity）信号作为外辐射源进行探测可获得较好的性能,然而Wi Fi信号本身及其应用环境的复杂性又决定了其参考信号获取的难度。该文分析了利用Wi Fi信号进行探测的特点,探讨了参考信号获取的不同方式,针对典型Wi Fi信号结构,提出了与Wi Fi无源探测相适应的参考信号重构方法,并结合接收信号的信噪比分析了参考信号重构质量对探测性能的影响。研究表明,参考信道所接收信号的信噪比越高,其解调误比特率越低,重构后的参考信号对于杂波抑制性能越好,其模糊函数噪声基底也越低,越有利于目标探测。同时,针对接收信号中的非监测信号成分所产生的虚假目标＂重影＂,提出了基于重构的参考信号修正方法进行消除。仿真分析表明了以上处理方法对参考信号获取的有效性。

英文摘要：

While Wireless Fidelity （WiFi）-based passive radar can achieve high detection resolution in both the range and Doppler domain, it is difficult to extract the reference signal because of the complexities of its signal format and application scenarios. In this study, we analyze a typical application of WiFi-based passive radar and discuss different methods for reference signal extraction. Based on the format and features of WiFi signals, we propose a method for reference signal reconstruction, and analyze the influence of the reconstructed reference signal’s performance on detection. The results show that higher reference SNRs generate lower decoding bit rate errors and better clutter suppression with the reconstructed reference signal. Moreover, we propose a method for removing irrelevant signals to avoid the impact on target detection of a non-direct path signal in the receiving signal. The experimental results validate the efficacy of the proposed signal processing method.