6-DoF Location-and-Pose Estimation Toward Integrated Visible Light Communication and Sensing: Algorithm Design and Performance Limits

Visible light communication (VLC) is envisioned as an important technique for short-range communications, but its potential for user device (UD) localization is not fully exploited, which is challenging due to diffuse-scattering interference and random fading. In this paper, we focus on the 6 degree-of-freedom (DoF) UD state estimation (i.e., 3D location and 3D pose angles) based on VLC. Specifically, a novel successive convex approximation (SCA)-based optimization algorithm is proposed, where UD location, pose angles and channel state are simultaneously estimated. Thus, the disturbance of random fading and diffuse-scattering interference for UD localization is alleviated via VLC-assisted channel equalization, and hence our SCA-based 6-DoF state detection solution outperforms state-of-the-art baselines. In addition, a unified performance analysis framework is established for VLC-based 6-DoF state detection, and structured information models are exploited for tractable performance quantification. A closed-form Cramer-Rao lower bound on UD localization error and pose angle estimate error is established respectively, and the impact of measurement noise, scattering interference, bandwidth, the quantities of photodiodes and light-emitting-diodes, etc, on the VLC-based UD state detection performance is analysed. Our closed-form analysis cannot only shed lights on the performance limits of VLC-based 6D state detection, but also gain insights into the impact of system configuration and fading environments.