scholarly journals Visible Light Wireless Data Center Links with Distinct Beam Configurations

2021 ◽  
Author(s):  
Jupeng Ding ◽  
Chih-Lin I ◽  
Lili Wang
Keyword(s):  
Visible Light ◽  
Data Center ◽  
Numerical Evaluation ◽  
Dynamic Range ◽  
Signal To Noise Ratio ◽  
Visible Light Communication ◽  
Optical Beam ◽  
Wireless Data ◽  
Data Signal ◽  
Snr Gain

Visible light communication (VLC) is being explored as one promising approach to enable wireless data centers (WDC). Up to now, the visible light wireless data center links are still limited to the conventional Lambertian beam paradigm. The potential coverage gain relevant to the optical beam space is waiting for sufficient investigation. For addressing this issue, in this paper, the dynamic optical beam based WDC coverage enhancement scheme is introduced, and for each transmitter, the best candidate asymmetrical optical beam is selected to load the data signal. Numerical evaluation shows that, compared with the conventional static beam configuration, up to 6.76 dB peak signal to noise ratio (SNR) gain and 4.46 dB average SNR gain could be provided by the proposed dynamic beam scheme. Moreover, this SNR dynamic range is reduced to 36.65 dB while the counterpart of the static non-Lambertian beam configuration is up to 44.78 dB.

scholarly journals A Full-Duplex LED-to-LED Visible Light Communication System

Electronics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1713
Author(s):  
Hyunwoo Jung ◽  
Sung-Man Kim
Keyword(s):  
Visible Light ◽  
Bit Error Rate ◽  
Error Rate ◽  
Signal To Noise Ratio ◽  
Light Emitting Diode ◽  
Visible Light Communication ◽  
Full Duplex ◽  
Signal To Noise ◽  
Light Emitting ◽  
Half Duplex

We experimentally demonstrated full-duplex light-emitting diode (LED)-to-LED visible light communication (VLC) using LEDs as the transmitter and receiver. Firstly, we investigated the performance dependency on the wavelengths of the LED transmitter and receiver by measuring the rise time and signal-to-noise ratio (SNR). Through the investigation, we were able to choose the optimal LED color set for LED-to-LED VLC using Shannon’s channel capacity law. The bit error rate (BER) results of full-duplex and half-duplex LED-to-LED VLC systems with the optimal LED sets are shown to compare the performance. Furthermore, we discuss major distortions and signal losses in the full-duplex LED-to-LED VLC system.

scholarly journals Polarization Differential Visible Light Communication: Theory and Experimental Evaluation

Sensors ◽  
2020 ◽  
Vol 20 (19) ◽  
pp. 5661
Author(s):  
Jorik De Bruycker ◽  
Willem Raes ◽  
Stanislav Zvánovec ◽  
Nobby Stevens
Keyword(s):  
Visible Light ◽  
Communication Theory ◽  
Rotation Angle ◽  
Signal To Noise Ratio ◽  
Visible Light Communication ◽  
Signal Quality ◽  
Polarization Direction ◽  
Signal To Noise ◽  
Research Attention ◽  
Analytical Expression

Visible Light Communication (VLC) has received substantial research attention in the last decade. The vast majority of VLC focuses on the modulation of the transmitted light intensity. In this work, however, the intensity is kept constant while the polarization direction is deployed as a carrier of information. Demodulation is realized by using a differential receiver pair equipped with mutually orthogonal polarizers. An analytical expression to evaluate the Signal-to-Noise Ratio (SNR) as a function of the rotation angle of the receiver is derived. It is demonstrated that the signal quality can deteriorate heavily with receiver orientation when using a single differential receiver pair. A way to overcome this drawback using two receiver pairs is described. The analytical expression is experimentally verified through measurements with two different receiver setups. This work demonstrates the potential of polarization-based modulation in the field of VLC, where receiver rotation robustness has been achieved by means of a dedicated quadrant photodiode receiver.

scholarly journals Performance evaluation of optical attocells configuration in an indoor visible light communication

2019 ◽  
Vol 14 (2) ◽  
pp. 668 ◽  
Author(s):  
M.S. M. Gismalla ◽  
M.F. L. Abdullah
Keyword(s):  
Visible Light ◽  
Power Distribution ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Data Communication ◽  
Visible Light Communication ◽  
Base Stations ◽  
Configuration Model ◽  
Received Power ◽  
Small Base

Visible light communication VLC is deemed as futuristic technology applied for both illumination and data communication due to the low-cost energy consumption, long life expectancy, huge bandwidth, and high security compared to radio frequency RF. Uncovered area, minimum signal-to-noise ratio (SNR) and received power results from the non-uniform distribution of small base stations (i.e. Optical attocells) in the room. In this paper, the researchers propose a new LEDs distribution of five optical attocells configuration model in order to optimize the received power distribution and SNR at the center of the room for indoor VLC system. The optical attocells configuration in terms of received power to fill the uncovered area at the center of the room has been investigated. The simulation results showed that the proposed attocells configuration saved 24.9% of the transmitted power. Besides that, the whole room was covered uniformly.  As a result, the received power and SNR are improved.

scholarly journals An Optimization of the Signal-to-Noise Ratio Distribution of an Indoor Visible Light Communication System Based on the Conventional Layout Model

2020 ◽  
Vol 12 (21) ◽  
pp. 9006
Author(s):  
Xiangyang Zhang ◽  
Nan Zhao ◽  
Fadi Al-Turjman ◽  
Muhammad Bilal Khan ◽  
Xiaodong Yang
Keyword(s):  
Visible Light ◽  
Communication System ◽  
Signal To Noise Ratio ◽  
Visible Light Communication ◽  
Optimal Layout ◽  
Signal To Noise ◽  
Ratio Distribution ◽  
Channel Quality ◽  
Reflected Light ◽  
Noise Ratio

For an actual visible light communication system, it is necessary to consider the uniformity of indoor illumination. Most of the existing optimization schemes, however, do not consider the effect of the first reflected light, and do not conform to the practical application conventions, which increases the actual cost and the complexity of system construction. In this paper, considering the first reflected light and based on the conventional layout model and the classic indoor visible light communication model, a scheme using the parameter Q to determine the optimal layout of channel quality is proposed. We determined the layout, and then carried out a simulation. For comparison, the normal layout and the optimal layout of illumination were also simulated. The simulation results show that the illuminance distributions of the three layouts meet the standards of the International Organization for Standardization. The optimal layout of channel quality in the signal-to-noise ratio distribution, maximum delay spread distribution, and impulse response is obviously better than the optimal layout of illumination. In particular, the effective area percentage of the optimal layout of channel quality is increased by 0.32% and 6.08% to 88.80% as compared with the normal layout’s 88.48% and the optimal layout of illumination’s 82.72%. However, compared with the normal layout, the advantages are not very prominent.

scholarly journals Designing of an Indoor Visible Light Communication Transceiver for Data Transmission using White LED

2016 ◽  
Author(s):  
Ha Duyen Trung ◽  
Do Trong Tuan
Keyword(s):  
Visible Light ◽  
Signal To Noise Ratio ◽  
Light Emitting Diode ◽  
Image Transmission ◽  
Visible Light Communication ◽  
Symbol Error Rate ◽  
Data Rate ◽  
Full Duplex ◽  
Light Emitting ◽  
Environment Experiment

Abstract: In this paper, a prototype of full-duplex indoor  Visible  Light  Communication  (VLC) transceiver  is  designed  to  demonstrate  an  optical wireless  system  based  on  Universal  Serial  Bus (USB) port for data transmissions using white Light Emitting  Diode  (LED).  Based  on  VLC  technology, the  designed  system  consists  of  transmitters  and receivers can achieve data rate of 161.2 Kbps error free at the distance of 92 cm between two computers for  real-time  text  and  image  transmission  over indoor  environment.  Experiment  results  show  that for text transmission, symbol error rate (SER) does not  vary  data  rate  at  some  transmission  distances, whereas  for  image  transmission,  minimum  square error (MSE) and peak signal to noise ratio (PSNR) indicate  that  the  received  image  and  transmitted image were almost similar.

scholarly journals Analysis of Visible Light Communication Link’s Performance in Fire Smoke Environment

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Yu-Feng Yang ◽  
Kang-Kang Chang ◽  
Ying Ci
Keyword(s):  
Visible Light ◽  
Signal To Noise Ratio ◽  
Visible Light Communication ◽  
Communication Link ◽  
Maximum Difference ◽  
Background Light ◽  
Opposite Trend ◽  
Received Power ◽  
Fire Smoke ◽  
In Fire

This paper mainly studies the communication performance of visible light communication link in fire smoke environment. Compared with the previous studies, this study no longer only considers a single wavelength and considers the influence of smoke and background light noise. Firstly, the variation of background light noise caused by sunlight during a day was analyzed, then signal-to-noise ratio (SNR) and bit error rate (BER) of the visible light communication link in fire smoke environment with different visibility were calculated, and finally, the variation of received power with the angle β between the LED optical axis and the communication link (from LED to receiver) was analyzed. The results show that, during a day from 07:00 to 18:30, background light noise first increases and then decreases, BER changes in the same trend and reaches the maximum at about 13:00, while SNR changes in the opposite trend and reaches the minimum at about 13:00. When visibility is 100 m, the maximum difference of SNR between 7:00 and 13:00 is about 19 dB, and the maximum difference of BER is about 5.3E-10. At 7:00, the maximum difference of SNR is about 13 dB between the visibility of 1 m and the visibility of 100 m, and the maximum difference of BER is about 1.44E − 11, and received power decreases with the increase of β. In addition, SNR increases with visibility of fire smoke environment, and BER changes in the opposite trend. Lastly, in order to enhance the performance of visible light communication in fire smoke environment, this paper gives the transmitting power scheme.

Sign in / Sign up

Export Citation Format

Share Document