Optimal Power Allocation for Integrated Visible Light Positioning and Communication System with a Single LED-Lamp

TL;DR

This paper presents an optimal power allocation strategy for a combined visible light positioning and communication system using a single LED-lamp, optimizing performance without pilot signals by leveraging location-dependent channel models.

Contribution

It introduces a novel system model that estimates channel state information from positioning data and derives bounds for positioning error and data rate, optimizing power allocation accordingly.

Findings

Optimized power allocation reduces positioning error and improves communication rate.

Derived bounds provide insights into system performance under various parameters.

Numerical results demonstrate the effectiveness of the proposed optimization.

Abstract

In this paper, we investigate an integrated visible light positioning and communication (VLPC) system with a single LED-lamp. First, by leveraging the fact that the VLC channel model is a function of the receiver's location, we propose a system model that estimates the channel state information (CSI) based on the positioning information without transmitting pilot sequences. Second, we derive the Cramer-Rao lower bound (CRLB) on the positioning error variance and a lower bound on the achievable rate with on-off keying modulation. Third, based on the derived performance metrics, we optimize the power allocation to minimize the CRLB, while satisfying the rate outage probability constraint. To tackle this non-convex optimization problem, we apply the worst-case distribution of the Conditional Value-at-Risk (CVaR) and the block coordinate descent (BCD) methods to obtain the feasible solutions. Finally, the effects of critical system parameters, such as outage probability, rate threshold, total power threshold, are revealed by numerical results.