Spectral and Energy Efficiency of ACO-OFDM in Visible Light Communication Systems

TL;DR

This paper analyzes the spectral and energy efficiency of ACO-OFDM in visible light communication, proposing optimal power allocation schemes and validating their performance through numerical analysis.

Contribution

It introduces a novel power allocation scheme for maximizing spectral and energy efficiency in ACO-OFDM VLC systems, considering practical input constraints.

Findings

Proposed a closed-form lower bound for spectral efficiency.

Developed a Dinkelbach-type iterative algorithm for energy efficiency maximization.

Validated the effectiveness of the schemes through numerical simulations.

Abstract

In this paper, we study the spectral efficiency (SE) and energy efficiency (EE) of asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM) for visible light communication (VLC). Firstly, we derive the achiev-able rates for Gaussian distributions inputs and practical finite-alphabet inputs. Then, we investigate the SE maximization problems subject to both the total transmit power constraint and the average optical power constraint with the above two inputs, respectively. By exploiting the relationship between the mutual information and the minimum mean-squared error, an optimal power allocation scheme is proposed to maximize the SE with finite-alphabet inputs. To reduce the computational complexity of the power allocation scheme, we derive a closed-form lower bound of the SE. Also, considering the quality of service, we further tackle the non-convex EE maximization problems of ACO-OFDM with the two inputs, respectively. The problems are solved by the proposed Dinkelbach-type iterative algorithm. In each iteration, the interior point algorithm is applied to obtain the optimal power allocation.The performance of the proposed power allocation schemes for the SE and EE maximization are validated through numerical analysis.