Abstract
A multi-user visible-light communication (VLC) system based on 4 × 4 multiple-input multiple-output (MIMO) was investigated. The system consists of four light-emitting diodes (as a transmitter) and four photodetectors (as a receiver). The proposed system was simulated for two, three, and four users. The objective of this study is to optimize the system power consumption and to utilize the sum rate on the system coverage area. By expanding the system from a 2 × 2 MIMO-VLC to a 4 × 4 MIMO-VLC, the results demonstrate that the total sum rate of the system can be improved. The findings reveal that the 4 × 4 MIMO-VLC achieves a maximum sum-rate enhancement of 143% compared with the 2 × 2 MIMO-VLC. The results also show that the efficiency of 4 × 4 MIMO-VLC system with non-orthogonal multiple access (NOMA) and gain ratio power allocation (GRPA) was increased by around 181% compared to 2 × 2 MIMO-NOMA-based VLC with GRPA in combination. For the 4 × 4 MIMO-NOMA-VLC device with GRPA, the sum bit rate for two, three, and four users was increased by 40%, 33%, and 24%, respectively. Through this study, it can be concluded that GRPA scheme plays an important role in utilizing MIMO-VLC system sum rate of the MIMO-VLC system.
Highlights
Ease of use and mobility are two important features provided by wireless devices, research interests to find other alternatives have been emerging in the field of optical wireless communications, especially visible-light communication (VLC) technology.[1]
The results show that after applying gain ratio power allocation (GRPA) on 4 × 4 multipleinput multiple-output (MIMO)-non-orthogonal multiple access (NOMA)-VLC, the achievable sum rate was improved
It can be seen that the sum rate of the 4 × 4 MIMO-NOMA-based VLC system with GRPA for both K 1⁄4 2, 3, and 4 was increased compared to that with OFDMA only. These findings clearly indicate the better performance for the device with GRPA
Summary
Ease of use and mobility are two important features provided by wireless devices, research interests to find other alternatives have been emerging in the field of optical wireless communications, especially visible-light communication (VLC) technology.[1] This is because VLC offers various advantages, such as license-free wide bandwidth, no electromagnetic interference, and low-power consumption.[2,3,4] VLC transmitters use high-brightness lightemitting diodes (LEDs) rather than the incandescent and fluorescent lamps of traditional light transmitters. Due to its outperformance of other technologies, VLC has recently attracted the attention of researchers, in Europe. Spectral efficiency and LED exploring capabilities were enhanced using a non-return-to-zero on–off keying modulation scheme, where the data rate reached was 100 Mbps.[7] In a single-input single-output architecture, a data rate of 3.5 Gbps was recently achieved using a single-color micro-LED.[8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
