An Optimal Scheme for the Number of Mirrors in Vehicular Visible Light Communication via Mirror Array-Based Intelligent Reflecting Surfaces

• Published in: Photonics Vol. 9; no. 3; p. 129
• Main Authors: Zhan, Ling, Zhao, Hong, Zhang, Wenhui, Lin, Jiming
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.03.2022
• Subjects: Algorithms; Arrays; Communication; Computer applications; Energy efficiency; energy efficiency (EE); intelligent reflecting surface (IRS); Iterative methods; Light; Maximum power; Noise; Optical communication; Optimization; Power consumption; Receivers & amplifiers; Reconfigurable intelligent surfaces; Signal processing; the number of mirrors; Transmitters; Vehicles; vehicular visible light communication (VVLC)
• ISSN: 2304-6732; 2304-6732
• DOI: 10.3390/photonics9030129

The optimization problem of the number of mirrors under energy efficiency (EE) maximization for vehicular visible light communication (VVLC) via mirror array-based intelligent reflecting surface (IRS) is investigated. Under considering that the formulated optimization problem is subject to the real and non-negative of the transmitted signal, the maximum power consumption satisfied luminous ability and eye safety, the minimum achievable rate, and the required bit error ratio (BER), EE is proved to be a unimodal function of the number of mirrors. Then, the binary search-conditional iteration (BSCI) algorithm is proposed for quickly finding the optimal number of mirrors with maximum EE. Numerical results demonstrate that fewer mirrors can obtain the maximum EE, and the computational complexity of the BSCI algorithm is reduced by 105 orders of magnitude, compared with the Bubble Sort method.