Enhancing User Mobility in Indoor Visible Light Communication System Using Intelligent Surface

Recently, the world has witnessed a tremendous increase in the number of devices connected to the Internet, i.e.Internet for everything (IOET), which requires high-speed data transfer, a wide bandwidth, and an appropriate coverage area.The radio frequencies of these advanced technologies in communications systems no longer meet these requirements, so the turn was to optical communications technology.Wireless is the best option because of its advantages, as its wide frequency range does not require a license and its energy consumption is low, in addition to its relatively cheap costs.On the other hand, it has some disadvantages, including limited coverage in the indoor environment, which leads to loss of signal, knowing that it mostly depends on the line-of-sight (LOS).This paper aims to improve the performance of MIMO-OOFDM systems in optical wireless communications systems.A novel method was developed to address the coverage issue of this system inside.This system is represented by a three-dimensional adaptive surface that aids in maintaining user communication continuity, particularly for the downlink.Scenarios were simulated depending on the number of photodetectors (PDs) and light emitters diodes (LEDs) and the number of levels of user sites, and the proposed surface was tested at several points from the room.it was found that there are always two effective photodetectors through the calculation of the channel matrix, while in traditional scanning there is a break in communication at points far from the center of illumination.The simulation was done with many photodetectors (N = 110) with (6) levels and was compared with the traditional system.The simulation results showed that the proposed system reduced the outage probability to a very high rate to become more efficient and reliable.