title: Wearable Sensor Localization Considering Mixed Distributed Sources in Health Monitoring Systems.
abstract: In health monitoring systems, the base station (BS) and the wearable sensors communicate with each other to construct a virtual multiple input and multiple output (VMIMO) system. In real applications, the signal that the BS received is a distributed source because of the scattering, reflection, diffraction and refraction in the propagation path. In this paper, a 2D direction-of-arrival (DOA) estimation algorithm for incoherently-distributed (ID) and coherently-distributed (CD) sources is proposed based on multiple VMIMO systems. ID and CD sources are separated through the second-order blind identification (SOBI) algorithm. The traditional estimating signal parameters via the rotational invariance technique (ESPRIT)-based algorithm is valid only for one-dimensional (1D) DOA estimation for the ID source. By constructing the signal subspace, two rotational invariant relationships are constructed. Then, we extend the ESPRIT to estimate 2D DOAs for ID sources. For DOA estimation of CD sources, two rational invariance relationships are constructed based on the application of generalized steering vectors (GSVs). Then, the ESPRIT-based algorithm is used for estimating the eigenvalues of two rational invariance matrices, which contain the angular parameters. The expressions of azimuth and elevation for ID and CD sources have closed forms, which means that the spectrum peak searching is avoided. Therefore, compared to the traditional 2D DOA estimation algorithms, the proposed algorithm imposes significantly low computational complexity. The intersecting point of two rays, which come from two different directions measured by two uniform rectangle arrays (URA), can be regarded as the location of the biosensor (wearable sensor). Three BSs adopting the smart antenna (SA) technique cooperate with each other to locate the wearable sensors using the angulation positioning method. Simulation results demonstrate the effectiveness of the proposed algorithm.
authors.affiliation: Department of Information and Communication Systems, Hohai University, Changzhou 213022, China. wanliangtian1@163.com.
authors.forename: Liangtian
authors.initials: L
authors.lastname: Wan
authors.affiliation: Department of Information and Communication Systems, Hohai University, Changzhou 213022, China. hanguangjie@hhu.edu.cn.
authors.forename: Guangjie
authors.initials: G
authors.lastname: Han
authors.affiliation: Department of Information and Communication Systems, Hohai University, Changzhou 213022, China. wanghaohhu@outlook.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: Guangdong Petrochemical Equipment Fault Diagnosis Key Laboratory, Guangdong University of Petrochemical Technology, Guangdong 525000, China. lei.shu@ieee.org.
authors.forename: Lei
authors.initials: L
authors.lastname: Shu
authors.affiliation: Institute of Electromagnetics and Acoustics, Xiamen University, Xiamen 361005, China. fengnaixing@gmail.com.
authors.forename: Nanxing
authors.initials: N
authors.lastname: Feng
authors.affiliation: School of Electronic and Communication, Shenzhen Institute of Information Technology, Shenzhen 518172, China. pengb@sziit.com.cn.
authors.forename: Bao
authors.initials: B
authors.lastname: Peng
keywords: direction-of-arrival (DOA) estimation; health monitoring systems; incoherently-distributed (ID) and coherently-distributed (CD) sources; virtual multiple input and multiple output (VMIMO)