Design And Performance Analysis Of Optical Intelligent Reflecting Surfaces Assisted Optical Wireless Communication System

Optical intelligent reflecting surface(OIRS),as a new type of digitally encoded metama-terial,can improve the coverage and power utilization efficiency of optical signals by changing the direction,shape,and quantity of the beam.This article conducts a comprehensive anal-ysis of OIRS from two aspects: OIRS's hardware structure characteristics and OIRS-assisted optical communication system.In terms of the hardware structure characteristics of OIRS,this paper compares and analyzes the characteristics and performance of the micromirror array and the optical phased array-type OIRS from the aspects of control mode,power utilization efficiency,beam splitting mode and multi-beam power distribution.We have established two types of physical models of OIRS.Based on these models,we derive the closed-form solution of OIRS's output power density distribution,power efficiency and control algorithm.Then,for two types of OIRSs,beam splitting and multi-beam power distribution algorithms are proposed.According to the analysis results,we also compare the performance of the two types of OIRSs in the actual system.Both experiments and simulations are proposed to verify the feasibility of the model and algorithm.In terms of analysis of OIRS-assisted optical communication systems,we propose a controllable multi-branch wireless optical communication system based on single-input single-output OIRS.By setting multiple OIRSs in the environment,we can build multiple artificial channels to improve system performance and reduce the possibility of communication interruption.When analyzing the performance of the communication system,we focus on three factors that affect the channel coefficients,including beam jitter,OIRS jitter,and obstruction probability.We derive closed-form probability density function of channel coefficients,asymp-totic average bit-error rate,and the outage probability for systems with multiple branches.Our analysis reveals that the probability density function contains an impulse function,which causes irreducible error rate and outage probability floors.Based on our numerical results,the bit-error rate and outage probability floor of the multi-branch system are significantly reduced compared with the single direct path system.Therefore,OIRS-assisted multi-branch wireless communi-cation is an effective solution for optical wireless communication in complex scenarios with obstacles.