Design Of The Receiver Of VLC System Based On MIMO Technology

VLC(visible light communication) system can get larger communication capacity and higher reliability with spatial multiplexing technique, which is also called MIMO(multi-input and multi-output) technology and is widely used in wireless communication system. Thus, VLC system based on MIMO technology is recognized as the best choice of high-speed VLC system. However, how to resolve the signal accurately and quickly is one of the key problems of MIMO VLC system.In this paper, we first introduce the basic concept of VLC system, discuss the classification and key technology of MIMO system and expound the advantages of MIMO technology in the visible light communication application.To update of channel matrix H automatically when the receiver moves in the room, a plan of using high-speed sampling rate and bad judgment redundant is proposed. Experiments show that, when the system sampling rate is greater than the 10 M, the channel matrix H can be update automatically. To realize imaging MIMO system by designing a property optical system and use it to simplify the process of recovering signal. In this way, less calculation and memory is used in DSP(digital signal process), furthermore, the cost of recovering the signal can be reduced and the speed of recovering can be higher. We designed a parabolic lens with reflectance film coated on the parabolic. Simulation results and theoretical analysis proves the practicability of this structure. Four advantages are put forward.Finally, the optimization scheme of the optical system design is presented. Optimization can save the cost of manufacture. Further, by tilting the structure, we find the limit angle of titling in the practical range.