- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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A Low-Cost Surveillance and Information System for Museum Using Visible Light Communication
摘要： This paper designed and implemented a low-cost surveillance and information system for museums with two new coding schemes using Visible Light Communication (VLC). For security, we use a key in place of the clock in the Manchester coding. For the enhanced data transfer, we use the unbalanced time duration for data one and zero. The prototype system was built with two low-cost microcontrollers, an LED, and linear light sensors. With 1 m distance in a dark environment, the maximum data transfer rate was roughly 1.93 kbits/s with a 10 Φ white LED. Under the dark-to-modest ambient brightness of up to 120 lux, the white LEDs were performed well in terms of the transmission to LEDs with different colors. The distance, compared experiments with flashlights reveal that our system can easily detect the prohibited use of flashlight. Experiments with the mobile phones’ flashlight also revealed that photographing with the flashlight would have a worse impact on arts than the continuous illumination. We also measured the distance between arts to avoid inevitable interference between illumination sources in neighbor.
关键词： Encoding,Indoor communication,Communication system security,Visible light communication
更新于2025-09-10 09:29:36
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Outage and error analysis of three hop hybrid VLC/FSO/VLC-based relayed optical wireless communication system
摘要： In this paper, we consider a three hop hybrid visible light communication/free space optical/visible light communication (VLC/FSO/VLC) system in which the information is transmitted from a room inside the building on a VLC link toward the decode and forward (DF) relay attached to that building. The relay maps the incoming signal on the FSO link and forwards it to the other DF relay attached to the second building, which further passes it down to the user inside the room onto the VLC downlink. The VLC and FSO links follow the Lambertian emission model and Gamma-Gamma fading statistics, respectively, under the impact of atmospheric turbulence, pointing errors, semiangle, and field of view of the detector. The performance of the three hop hybrid system is derived in terms of the closed-form expression for the outage probability. The error performance is analyzed in terms of average symbol error probability of the considered hybrid system. Furthermore, an expression for asymptotic outage probability of the system is derived to investigate the behavior of the system at high signal-to-noise ratio (SNR) regimes. The impact of variation in the parameters on the hybrid VLC/FSO//VLC communication system performance is illustrated by the numerical plots.
关键词： free space optical,relayed optical wireless communication,outage probability,average symbol error probability,visible light communication
更新于2025-09-10 09:29:36
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Adaptive Thresholding Scheme for Demodulation of Rolling-Shutter Images Obtained in CMOS Image Sensor Based Visible Light Communications
摘要： Light-emitting-diode transmitter and complementary-metal–oxide–semiconductor (CMOS) image sensor receiver based visible light communication is a promising scheme for an optical wireless communication. During the demodulation of the rolling shutter pattern obtained from the CMOS image sensor Rx, due to the high signal fluctuation introduced by the uneven light exposure, special thresholding schemes are needed to correctly identify the data logic. In this work, we propose and demonstrate a modified adaptive scheme (MQA) for the demodulation of the rolling shutter pattern. Experimental bit-error-ratio (BER) measurements using different thresholding schemes at different illuminance are analyzed. The results show that the proposed MQA scheme can provide much lower BER, with similar process latencies when compared with other schemes.
关键词： visible light communication (VLC),Light emitting diode (LED),CMOS image sensor.
更新于2025-09-10 09:29:36
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Improved Joint Generalized Spatial Modulations for MIMO-VLC Systems
摘要： In this letter, we propose the computationally efficient constellation design algorithms for single-mode and dual-mode joint generalized spatial modulations (JGSMs) to improve the symbol error rate (SER) performance over highly correlated indoor visible light communication channels. Our simulation results show that the proposed joint and improved dual-mode JGSMs can offer a better SER performance than the proposed single-mode JGSM (SM-JGSM) and the conventional SM-JGSM, which are validated through the analytical bounds.
关键词： Correlated channels,multiple-input multiple-output (MIMO),visible light communication (VLC),joint generalized spatial modulation (JGSM)
更新于2025-09-10 09:29:36
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[IEEE 2017 IEEE International Conference on Computational Intelligence and Computing Research (ICCIC) - Coimbatore, India (2017.12.14-2017.12.16)] 2017 IEEE International Conference on Computational Intelligence and Computing Research (ICCIC) - Multiuser Visible Light Communication System For Reliable Wireless Communication
摘要： Visible Light Communication (VLC) is evolving likewise a guaranteeing act on give pervasive remote association. In this paper, we study an indoor multiuser Visible Light Communication framework can substantially increase the achievable bit rate of Adaptively Modulated Optical Orthogonal Frequency-Division Multiplexing (AMO-OFDM) system and has the ability to maximise data throughput by adjusting the number of bits per subcarrier based on the set of subcarrier's channel Gain to Noise Ratio (GNR). For each subcarrier resolved alongside OFDM, those comparing precoding grids will be in the recurrence area to eradicate multiuser viewed as obstruction. VLC is one of the promising candidates because of its features of non-licensed channels, high bandwidth and low power consumption. As a visible light source can be used both for illumination and communication, therefore, it saves the extra power that is required in RF communication. The revolution in the field of solid state lighting leads to the replacement of florescent lamps by Light Emitting Diodes (LEDs) which further motivates the usage of VLC.The modulation bandwidth of white emanation is about ～2MHz.
关键词： VLC (Visible Light Communication),Multiple transmitter and receiver links,MIMO (Multiple Input Multiple Output),OFDM (Orthogonal Frequency Division Multiplexing),MMSE (Minimum Mean-Squared Error),Precoding
更新于2025-09-10 09:29:36
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Evaluating the risk of eavesdropping a visible light communication channel
摘要： Visible light communication (VLC) technologies are becoming a method to communicate with a wide range of devices. One of VLC's biggest proposed advantages is the inherent security that this technology provides. The concept of securing on VLC is based on its indoor use since optical radiation is confined by walls. However, doors and windows are usually present in any inhabited structure through which the optical signal can leak and be detected by external devices. In this study, the signal leaked through such a window and the risk of eavesdropping the VLC-based channel may have is studied. In this way, a risk evaluation parameter, which includes different variables, is proposed and analysed.
关键词： Visible light communication,eavesdropping,security,risk evaluation,VLC
更新于2025-09-10 09:29:36
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[IEEE 2018 10th International Conference on Information Technology and Electrical Engineering (ICITEE) - Bali, Indonesia (2018.7.24-2018.7.26)] 2018 10th International Conference on Information Technology and Electrical Engineering (ICITEE) - A Circuit for Robust Visible Light Communication Systems in Indoor Environment
摘要： In the recent decades, Visible light communication (VLC) becomes the favorite research topic in the world. VLC has been successfully applied to the outdoor or indoor area though not yet en masse. The VLC transceivers operating in typical indoor environments are subject to intense ambient light, emanating from both natural and artificial sources. The primary sources of ambient light as mentioned before are the background light comes from sunlight, DC light sources (LED bulb & flashlight), incandescent and fluorescent lamps. These signal must be filtered-out because it will make the received signal distortion. Previous research about low-cost Analog Front-End (AFE) circuit has been carried out on the simulation only. This research is trying to test the designed AFE receiver circuit on the laboratory. Moreover, we add the several analog blocks to be involved. The test data obtained; the designed circuit able to compensate the optical noise. It makes VLC system has robustness ability from other lights in the indoor environment.
关键词： Indoor Environment,Visible light communication,Robust VLC,Analog Front-End
更新于2025-09-10 09:29:36
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Convolution neural network-based time-domain equalizer for DFT-Spread OFDM VLC system
摘要： This paper presents a novel time-domain equalizer for visible light communication (VLC) system using machine learning (ML) method. In this work, we employ discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) as modem scheme and convolution neural network (CNN) as kernel processing unit of equalizer. After estimating channel state information (CSI) from training sequence, the proposed equalizer recovers transmitted symbols according to the estimated CSI. Numerical simulations indicate that the equalizer can significantly enhance bit error rate (BER) performance. For example, when signal-to-noise ratio (SNR) is 20dB and 16/32/64-quadrature amplitude modulation (QAM) is exploited, original BER is about 0.5 while the BER after recovery achieves 10?5, which is much lower than forward error correction (FEC) limit 3.8×10?3. This work promotes the application of ML in VLC domain. To the best of our knowledge, this is the first time a CNN-based equalizer has been explored.
关键词： Machine learning (ML),Discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM),Visible light communication (VLC),Convolution neural network (CNN)
更新于2025-09-10 09:29:36
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Outage of SEE-OFDM VLC-NOMA Networks
摘要： In this letter, an indoor spectrally and energy efficient orthogonal frequency division multiplexing (SEE-OFDM) based visible light communication (VLC) network with non-orthogonal multiple access (NOMA) is studied. An exact expression of the outage probability for K NOMA users is derived. We also provide an upper bound of the data rate of the SEE-OFDM VLC-NOMA network. Finally, the proposed system model shows its superiority compared to the orthogonal multiple access.
关键词： outage probability (OP),visible light communication (VLC),Non-orthogonal multiple access (NOMA)
更新于2025-09-10 09:29:36
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[ACM Press the 17th ACM Workshop - Redmond, WA, USA (2018.11.15-2018.11.16)] Proceedings of the 17th ACM Workshop on Hot Topics in Networks - HotNets '18 - Connecting Battery-free IoT Tags Using LED Bulbs
摘要： We introduce BackVLC, a system to connect battery-free IoT tags using LED bulbs. We make use of bulbs beyond illumination. We send data to the tags with visible light communication (VLC), and retrofit the bulbs with simple circuitry to enable the uplink channel current VLC systems lack, using Radio Frequency (RF) backscatter communication from the tags. Tags process and send data, harvesting energy from light and radio. We present our system design and implementation, evaluate it in preliminary simulation studies and experiments, and discuss the research challenges to develop a complete network architecture. BackVLC is the first work that combines VLC with RF backscatter.
关键词： RF backscatter,LED bulbs,visible light communication,battery-free IoT tags,BackVLC
更新于2025-09-10 09:29:36