FMCW无线电波反射室内人员跟踪系统回波检测方法

Echo detection method for indoor personnel tracking system based on FMCW radio wave reflection

针对基于调频连续波(FMCW)无线电波反射的室内人员定位跟踪系统中的目标回波信号检测问题,提出了一种频域检测方法。将反射回波与FMCW的差频信号进行连续M次采样后,变换为频域信号,采用恒虚警率(CFAR)准则在频域上设置差频信号的检测门限,通过比较门限,判决出差频信号的首个频率分量,从而实现了目标回波信号的检测。通过理论推导得到CFAR与频域门限的关系,并通过仿真分析了不同参数对检测性能的影响。结果表明,提出的检测方法能准确地提取到回波信号的首个频率分量。

A frequency domain detection method is proposed aiming at the problem of target echo signal detection in indoor personnel localization and tracking system based on frequency module carrier wave( FMCW) radio wave reflection. Frequency offset between after reflected echo and difference frequency signals of FMCW are sampled M times,and then transfer to frequency domain signal,detection threshold of difference frequency signal in frequency domain is set by constant false alarm rate( CFAR),through comparing threshold,the first component of frequency is judged and thus echo signal detection of the target is realized. Relationship between CFAR and frequency dmain threshold is obtained by derivation,and the effects of different parameters on the detection performance are analyzed. Simulation results show that the proposed detection method can accurately extract the first frequency component of echo signal.