Design of an optical attocells configuration for an indoor visible light communications system

Improve uniformity for an indoor visible light communication system

“…In order to improve the receiver gain and enhance the received power and SNR distribution, the FOV should be decreased, but not less than the limited value in order to avoid the blind area of the room as in Komine and Nakagawa . In this study, an optimized FOV of 40° was used based on findings from Gismalla et al for the proposed model.…”

“…In previous studies, several design models were introduced to improve uniformity distribution and VLC system performance as well. [14][15][16][17][18][19][20][21][22][23] Single and four-optical attocells configuration models were introduced in Nguyen et al 20 and Ganjian et al 21 ; they were evaluated in terms of their received power, signal-to-noise ratio (SNR), and illumination levels. Results showed that four optical attocells had more uniformity; however, a drop at the center and corners of the room was observed at small and wide optical attocell angles, respectively.…”

“…One of the most popular LED array configurations used in indoor environments is square and hollow LEDs array. In previous studies, several design models were introduced to improve uniformity distribution and VLC system performance as well . Single and four‐optical attocells configuration models were introduced in Nguyen et al and Ganjian et al; they were evaluated in terms of their received power, signal‐to‐noise ratio (SNR), and illumination levels.…”

“…Thus, a clear trade‐off between system performance and complexity was observed. In a recent study by Gismalla et al, authors have proposed an optical attocells configuration model to acquire an improved uniformity at lower power consumption, while increasing the number of attocells in the room by installing one optical attocell at the center of the ceiling. Similarly, Azizan et al proposed three topologies of six optical attocells to improve the quality of communication in terms of SNR distribution; however, a drop at the corners of the room was observed as well.…”

Performance enhancement for a non-orthogonal multiple access system using 4 × 4 multiple-input multiple-output visible-light communication

“…8 To date, a range of schemes has been introduced to boost efficiency and expand the VLC system coverage. 9 The most common and efficient method is the multiple-input multiple-output (MIMO) scheme, with arrays of illuminating LEDs. 10,11 Meanwhile, 150 Mbps over 6 m using on-off keying and 100 Mbps over 0.6 m using orthogonal frequency-division multiplexing (OFDM) modulation with a 2 × 2 MIMO was demonstrated in Refs.…”