摘要
蓝牙技术联盟在蓝牙5.1规范引入寻向功能,为大幅提升蓝牙定位技术的精度提供了新的解决途径,但并未对信号的角度测量算法提供统一方案。针对低功耗蓝牙在室内环境多径干扰下到达角估计困难这一问题,提出了一种面向矩形阵列的改进二维MUSIC算法,通过对矩形阵列天线阵元进行二次划分,采用前后向平滑的方法修正一维子阵的协方差矩阵,再利用接收信号矩阵的广义逆求出各个子阵协方差的关系,从而修正整个阵列接收信号的协方差矩阵。该算法在没有降低信号协方差矩阵维数的同时,恢复了信号协方差矩阵的秩,有效抑制室内多径信源引起的干扰。经过仿真实验,证明了本文算法在低快拍数、低信噪比的情况下对角度估计的精度有着较大改善。并设计了相应的硬件系统进行室内与室外的实验,结果表明在多径干扰严重的室内定位时定位精度改善更为明显,室内定位圆概率误差降低了26.75%~60.25%。仿真和现场定位实验证明了本文提出角度估计算法的有效性,该算法对其他应用领域的来波方向估计也具有重要参考意义。
The Bluetooth SIG announced support for angle of arrival(AoA)and angle of departure(AoD)in the Bluetooth 5.1 specification,which provides a new solution to greatly improve the precision of Bluetooth positioning.However,the Bluetooth 5.1 does not provide a unified algorithm for angle calculation.An improved two-dimensional MUSIC algorithm based on rectangular array was proposed to solve the problems of angle calculation caused by serious multipath interference in indoor environment.The antenna array is divided twice,and the covariance matrix of one-dimensional subarray is corrected by the method of forward and backward smoothing,and the covariance matrix of the whole array is corrected by the generalized inverse of the received signals matrix.This algorithm restores the rank of the signals covariance matrix without reducing the dimension of the signals covariance matrix,interference caused by indoor multipath sources can be effectively suppressed.Through the simulation experiment,it is proved that the proposed algorithm can greatly improve the accuracy of angle estimation under the condition of low fast beat number and low SNR.Positioning system is designed for indoor and outdoor experiments.The results show that the improvement of location accuracy is more obvious in indoor location.The circular probability error of stationary location is reduced by 26.75%~60.25%in the indoor environment.Simulation and indoor positioning experiments show the effectiveness of the angle estimation algorithm proposed in this paper,this algorithm also has important reference significance for direction of arrival estimation in other application fields.
作者
韦子辉
蔡大鑫
叶兴跃
李小阳
方立德
孔祥杰
Wei Zihui;Cai Daxin;Ye Xingyue;Li Xiaoyang;Fang Lide;Kong Xiangjie(School of Quality and Technical Supervision,Hebei University,Baoding 071002,China;National Local Joint Engineering Research Center for Measuring Instruments and Systems,Baoding 071002,China)
出处
《电子测量与仪器学报》
CSCD
北大核心
2022年第10期157-165,共9页
Journal of Electronic Measurement and Instrumentation
基金
国家自然科学基金(61475041)
京津冀协同创新共同体建设专项(20540301D)
河北省自然科学基金重点项目(F2021201031)资助
关键词
蓝牙定位
达到角估计
矩形阵列
MUSIC算法
Bluetooth positioning
angle of arrival estimation
rectangular array
MUSIC algorithm
