Research On The F-OGSM Algorithm Based On Location Retrieval In The VLC System

Visible light communications（VLC）is a wireless communication technology that uses visible light,which ranges from 385 THz to 789 THz,as the carrier and transmits information through the rapid blinking of Light Emitting Diodes（LEDs）.Indoor VLC technology not only needs to meet lighting requirements,but also needs to consider communication.Therefore,in visible light indoor lighting scenarios,a multi-LED array layout is usually adopted,especially in large scenes where the number of LED arrays increases sharply,making the reliability and applicability of traditional multiple-input multiple-output（MIMO）systems uncertain.Based on this,this paper conducts in-depth research on the light source layout,spatial modulation,generalized spatial modulation,and full-light generalized spatial modulation algorithms involved in VLC-MIMO systems.and solves the problem of insufficient channel capacity of the MIMO system.At the same time,in order to further improve the scope of application of the VLC-MIMO system,a position retrieval antenna selection algorithm based on Pearson coefficients is proposed to achieve performance guarantee in sub-regions and further improve the communication quality of MIMO systems.The specific research contents are as follows:Firstly,based on the Lambert radiation model,a layout model of indoor 4 LED arrays is designed,and simulation analysis shows that the layout model conforms to international lighting standards;At the same time,a VLC-MIMO channel model is built based on the layout model,and the channel capacity of the MIMO system is derived from the channel capacity of the single input,single output system.The simulation shows that when the signal-to-noise ratio is 20 d B,the capacity of the 4×4 MIMO channel increases by about 15 bits/s compared to the 1×1 channel.Secondly,in order to solve the problems of inter-channel interference and antenna synchronization in VLC-MIMO,optical spatial modulation,optical generalized spatial modulation and fully generalized optical spatial modulation are introduced into the VLC-MIMO system at the transmitter,greatly improving transmission performance through a reasonable selection of the number of transmit antennas.Thirdly,in order to further improve the system communication quality and applicable scenarios in large scenarios,traditional antenna selection algorithms are introduced into OSM-MIMO,OGSM-MIMO,and F-OGSM systems.As the efficiency of traditional antenna selection algorithms in improving system performance decreases as the number of antennas increases,this paper proposes a location retrieval antenna selection algorithm based on Pearson coefficients.By calculating the Pearson coefficient correlation between the central luminous intensity of different combinations of LED arrays and the illumination received by photodetectors at different positions,the optimal antenna combinations are obtained.Finally,for OGSM-MIMO and F-OGSM systems with different antenna selections,simulation analysis shows that the Pearson coefficient based location retrieval antenna selection algorithm is optimal.When the bit error rate reaches 10^-3,in OGSM-MIMO systems,the Pearson coefficient based location retrieval antenna selection algorithm reduces the signal-to-noise ratio by about 3d B compared to the norm antenna selection algorithm;The norm antenna selection algorithm reduces the signal-to-noise ratio by 1 d B compared to the RSS based antenna selection algorithm;In the F-OGSM system,the position retrieval antenna selection algorithm based on the Pearson coefficient reduces the signal-to-noise ratio by about 3d B compared to the norm antenna selection algorithm;The norm antenna selection algorithm reduces the signal-to-noise ratio by 0.5 d B compared to the RSS based antenna selection algorithm.