# Image Sensor-Based Three-Dimensional Visible Light Positioning for Various Environments

## TL;DR

This paper introduces a 3D visible light positioning system using image sensors and an algorithm to improve accuracy in different environments.

## Contribution

A novel 3D positioning system using height–size curve fitting and a firefly-assisted particle filter for improved accuracy.

## Key findings

- The system achieves a positioning error under a single LED of within 10 cm.
- The FA-UPF algorithm reduces average positioning error to 6.45 cm when no light source is detected.

## Abstract

Research on image sensor (IS)-based visible light positioning systems has attracted widespread attention. However, when the receiver is tilted or under a single LED, the positioning system can only achieve two-dimensional (2D) positioning and requires the assistance of inertial measurement units (IMU). When the LED is not captured or decoding fails, the system’s positioning error increases further. Thus, we propose a novel three-dimensional (3D) visible light positioning system based on image sensors for various environments. Specifically, (1) we use IMU to obtain the receiver’s state and calculate the receiver’s 2D position. Then, we fit the height–size curve to calculate the receiver’s height, avoiding the coordinate iteration error in traditional 3D positioning methods. (2) When no LED or decoding fails, we propose a firefly-assisted unscented particle filter (FA-UPF) algorithm to predict the receiver’s position, achieving high-precision dynamic positioning. The experimental results show that the system positioning error under a single LED is within 10 cm, and the average positioning error through FA-UPF under no light source is 6.45 cm.