arrow
Return

Approximate Maximum-Likelihood RIS-Aided Positioning

delete2023-12-01
delete0
delete
OA
AI
W
Wei Zhang *
Z
Zhenni Wang
W
Wee Peng Tay
DOI:10.1109/TWC.2023.3266457delete
deleteOriginal
deleteOriginal request for help
deleteShare
deleteSave
Abstract

Abstract

En 中文
A reconfigurable intelligent surface (RIS) allows a reflection transmission path between a base station (BS) and user equipment (UE). In wireless localization, this reflection path aids in positioning accuracy, especially when the line-of-sight (LOS) path is subject to severe blockage and fading. In this paper, we develop a RIS-aided positioning framework to locate a UE in environments where the LOS path may or may not be available. We first estimate the RIS-aided channel parameters from the received signals at the UE. To infer the UE position and clock bias from the estimated channel parameters, we propose a fusion method consisting of weighted least squares over the estimates of the LOS and reflection paths. We show that this approximates the maximum likelihood estimator under the large-sample regime and when the estimates from different paths are independent. We then optimize the RIS phase shifts to improve the positioning accuracy and extend the proposed approach to the case with multiple BSs and UEs. We derive Cramer-Rao bound (CRB) and demonstrate numerically that our proposed positioning method approaches the CRB.
Keywords:
Channel estimation
Clocks
Wireless communication
Reflection
MIMO communication
Estimation
Three-dimensional displays
Reconfigurable intelligent surface
positioning
mmWave communications
Cramer-Rao bound

Journal

IEEE Transactions on Wireless Communications cover
IEEE Transactions on Wireless Communications
IF:
10.7
Papers:
1.3W
Citations:
5.3W

Organization

N
Nanyang Technological University
Scholars:
4.9W
Papers: 4.8W
Citations: 8.1W
C
City University of Hong Kong
Scholars:
2.3W
Papers: 3.0W
Citations: 6.1W