Parametric Variational Sum-Product Algorithm for Cooperative Localization in Wireless Sensor Networks

Wei Li,Dong Liu

doi:10.1109/access.2021.3090566

Abstract

Communication overhead is a key task for the large-scale wireless sensor networks (WSNs) in the cooperative localization problems. This paper is aimed to propose a low-overhead algorithm without sacrificing the performance of localization, which is more practical for energy-saving WSNs. In this paper, the cooperative localization problem is formulated as a variational reference problem on a factor graph (FG). Combining the high performance of particle-based algorithms and the overhead advantage of parametric ones, a parametric variational sum-product algorithm (PVSPA) is proposed for the cooperative localization of WSNs. In prediction operation, to ensure high accuracy, messages referenced inside sensor nodes are particle-based. In correction operation, Gaussian parametric representation is adopted to the observation message and the communication overhead is obviously decreased. Simulation results show that the localization accuracy of PVSPA equally matches the classic particle-based algorithms, while the communication overhead of it is far lower.

Highlights

In wireless sensor networks (WSNs), information collected and communicated by a wireless sensor node is usually valuable only if the node’s location is known
In cooperative localization problems, where the accurate clock synchronization must be taken into consideration [7], only a few sensor nodes know their coordinates in WSNs, while the others with unknown positions need to estimate their own positions, by exploiting absolute position information available from a few reference anchors and relative position information obtained from measurements with neighboring targets [8]
EVALUATION To verify the performance of parametric variational sum-product algorithm (PVSPA), this section uses MATLAB 9.4.0 to simulate the application of PVSPA for cooperative localization in WSNs

Summary

Introduction

In WSNs, information collected and communicated by a wireless sensor node is usually valuable only if the node’s location is known. In cooperative localization problems, where the accurate clock synchronization must be taken into consideration [7], only a few sensor nodes (referred as anchors) know their coordinates in WSNs, while the others (referred as targets) with unknown positions need to estimate their own positions, by exploiting absolute position information available from a few reference anchors and relative position information obtained from measurements with neighboring targets [8]. Literature [13] provide a unified factor graph-based framework for passive localization in WSNs based on TOA measurements. In these message passing algorithms, how messages are represented (particle-based or parametric representation) for computation and transmission depends largely on computational complexity and communication overhead [14]. Literature [14], based on the SPAWN algorithm [15], point out that due to the limited energy of WSNs, the message representation method requires a VOLUME XX, 2017

Objectives

Results

Conclusion