Impact of multipath effects on theoretical accuracy of TOA-based indoor VLC positioning system

Abstract

This paper discusses the time-of-arrival (TOA) based indoor visible light communication (VLC) positioning system in a non-line-of-sight environment. The propagation delay is assumed to be gamma distributed. The generalized Cramer-Rao lower bound for multipath propagation is derived as the theoretical accuracy limitation. The performance of the positioning system is affected by the shape parameter and the scale parameter of gamma distribution. The influences on positioning accuracy of multipath effects are analyzed through discussing the physical meaning of the gamma distribution parameters. It is concluded that the lower bound of positioning accuracy is attained when variance of the non-line-of-sight propagation-induced path lengths is zero. The simulation result proves that the theoretical positioning accuracy is in the order of centimeters with the given scenario.

A Survey of Positioning Systems Using Visible LED Lights

“…LED-based positioning systems can also be affected by multipath effect. The effects on RSS-based and TOA-based positioning systems were studied in [60][61][62][63].…”

“…The impact of the multipath effect on a TOA system was studied in a NLOS environment [63]. This system generated prior information of the NLOS distribution using NLOS propagation-induced path lengths modeled by gamma distribution [64].…”

Convex Polygon Positioning for Homogeneous Optical Wireless Networks

“…A positioning error of 9.8 mm was achieved when no multipath effect was considered whilst the error increases to 1.7 m when reflections were introduced in the simulation using a reflection factor of of 0.66. The effect of multipath in TOA-based localization was studied in [15]. The Generalized Cramer-Rao lower bound (G-CRLB) was obtained modeling reflections path by gamma distribution.…”

United block sequence mapping-based visible light positioning for dense small cell deployment

“…An unprecedented opportunity for visible light communication and visible light positioning (VLP) is brought by the introduction of white LEDs for illumination and extensive research has been done [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] . Techniques based on different parameters are applied in VLP.…”

“…[8], an VLP system based on time differences of arrival (TDOA) can achieve an estimation accuracy of 3.6 cm on average in the simulation and the impact of multipath effects on the theoretical accuracy of time of arrival based indoor VLP positioning system is analyzed in Ref. [9]. In Ref.…”