چكيده به لاتين
Optical Wireless Communciation (OWC) links are an appropriate complement for radio frequency communication systems. The most important advantageous of OWC systems are the wide and unregulated band as well as its high security. Visible Light Communication (VLC) is a subset of OWC systems. VLC systems are the promising solution as an alternative for the fully-occupied radio frequency bands in near future. The rear (tail) and front of vehicles have lamps which can be used for vehicular visible light communication (VVLC) systems. On the other hand, one of the most important challenges of VLC systems is the line-of-sight (LoS) blockage issue. In this project, we propose the installation of Intelligent Reflecting Surfaces (IRSs) (i.e., smart mirrors, and Metasurfaces) on the back of vehicles to overcome this challenge for VVLC systems. In this regard, we assume three different patterns of angular distribution for the radiation intensity, such as a commercially available LED with an asymmetrical pattern (Philip Luxeon Rebels), Symmetrical Lambertian pattern, and Asymmetrical Gaussian pattern. The structure of this project is summarized as follows: in the first chapter, the introduction and related works to VVLC and IRS systems are discussed. In chapter two, we obtain the channel model for the Smart mirror VVLC systems, then the evaluation of the path loss results versus link distances under different conditions such as weather type (clear weather, rainy, moderate fog, and thick fog) and radiation patterns is investigated. Also, the impact of system parameters such as aperture size of the photodetector (PD), side-to-side and front-to-front distances, number of IRS elements, and IRS area are investigated. In the second section of this chapter, we derive a closed-form expression for the maximum achievable link distance versus the probability of error for the IRS-based VVLC system. In third section, the channel capacity for IRS-based VVLC systems with two types of receivers, namely, APD and SPAD, are analyzed. In chapter three, other types of intelligent reflecting surfaces called Metasurfaces with constant and variant reflection coefficient (Liquid Crystals) are introduced. Then, the comparison of the path loss result and maximum achievable distance based on the three IRS types (Smart mirrors, Metasurfaces with constant reflection coefficients, Metasurfaces with variant reflection coefficients) are shown. The fourth chapter is dedicated for the suggestions and results of this project.
