目前,用于室内定位的雷达技术为了达到高精度而使用高带宽的调频连续波,这样不仅对设备要求高且杂波干扰大。为降低带宽开销,该文使用双频连续波比相测距机制来实现室内人体定位。在该方法中复杂的室内环境和人体变化的移动速度会造成频谱扩展,导致有效信号信噪比降低,能量发散甚至出现峰值误判,直接降低测速和定位的精度。由此,提出应用于室内环境中的基于双频连续波比相测距的局部速度差补偿算法,以校准频域信号,获取高精度的速度与距离信息。实验结果表明在设备功率提供的测距范围内固定位置均方根误差在9~14 cm内,与已有调频连续波有同等级的测距精度,最终实现了低带宽下的高精度人体定位。同时该系统的算法复杂度较低,能更好地适用于人体轨迹的实时跟踪。
The radar technology used in indoor localization prefers wide bandwidth frequency modulated continuous wave for high accuracy, yet this way needs specific device and suffers from clutters. In order to reduce the bandwidth overhead, the indoor human localization is implemented based on dual frequency continuous wave phase ratio. However, the receive signal spectrum spreads due to the complex indoor environment and the changing moving speed. The spectrum spread will leads to SNR reduction, energy divergence and wrong peak value, which decrease velocity measuring and localization accuracy. To improve the location accuracy, the frequency domain signal is calibrated with the proposed partial velocity deviation compensation algorithm in the dual frequency phase ratio localization. The experiment results show that the root mean square error of the distance measuring is as high as 9 - 14 cm in low bandwidth, which is parallel to the state of art. Moreover, the indoor localization and tracking can work in real time by using the proposed low complexity algorithm.