- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Handbook of Position Location (Theory, Practice, and Advances, Second Edition) || Visible Light-Based Communication and Localization
摘要： Solid-State device light-emitting diodes (LEDs) are rapidly being embedded in different commonly used devices, as are photodiodes and image sensors. Furthermore, illumination using LED reduces power consumption and motivates decorative illumination design. Because LED-based light sources are widely available, there are several options for visible light communication and positioning systems. This chapter provides an overview of the technologies that have paved the way for visible light communication and positioning systems.
关键词： photodiode,VLC,indoor positioning,VLP,visible light positioning,image sensor,LED,visible light communication
更新于2025-09-19 17:15:36
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LuxSteg: First Practical Implementation of Steganography in VLC
摘要： Visible-light communication (VLC) is a new technique for high-speed, low-cost wireless data transmission services. One of the areas in which VLC is considered superior to traditional radio-based communication is security. The common slogan summarizing the VLC security features is WYSIWYS—''What You See Is What You Send.'' However, the broadcast nature of downlink VLC makes it possible for eavesdroppers to easily intercept the light communication in various settings, e.g., offices, conference rooms, plenum spaces, and so on. Similarly to radio-based data broadcasting systems, such as Wi-Fi, VLC opens the possibilities of hiding information in the public channel. In this paper, we describe (for the first time, to the best of our knowledge) the implementation of steganographic data transmission in a VLC system called LuxSteg. This VLC system utilizes pulse position modulation and direct sequence-code division multiple access modulation. In our implementation, multiple steganographic data streams are mixed with the spreading codes and combined with the overt data stream. We achieve a steganographic transmission rate of approximately 1 Mb/s hidden in a 110-Mb/s data stream. We analyze the influence of the spreading factor, spreading code type, number of hidden data streams, and the amplitude on the achievable transmission rate, undetectability, and robustness.
关键词： network security,computer networks,Communication system security,visible light communication
更新于2025-09-19 17:15:36
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[IEEE 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Sydney, Australia (2018.11.21-2018.11.23)] 2018 28th International Telecommunication Networks and Applications Conference (ITNAC) - Analysis of the effects of multiple reflection paths on high speed VLC system performance
摘要： In the recent past, research in visible light communication (VLC) has gained a lot interest due to its distinct characteristics in supporting high-speed data transmission and illumination simultaneously. To implement a reliable VLC system, few parameters have to be considered for communication channels such as distance between transmitter and receiver, data rate, line of sight (LOS) and non-line of sight (NLOS) communication paths, signal power and delay of the channel. In this paper, we designed and simulated a LOS and NLOS multipath VLC model using single and multiple LEDs. Basic on-off keying (OOK) modulation scheme and available conventional LED configuration have been considered to analyze the effects of field of view (FOV) and the reflection of the light signal on received power level. Moreover, BER and quality of transmission were measured for single and multipath transmissions considering distance, incident and irradiance angles.
关键词： BER,LED refraction,Visible Light Communication,multi-channel,FOV,irradiance and incident angle
更新于2025-09-19 17:15:36
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Spatial Carrierless Amplitude and Phase Modulation Technique for Visible Light Communication Systems
摘要： Spatial carrierless amplitude and phase modulation (S-CAP) technique is developed in this paper as a physical layer solution to improve the spectral efficiency of the conventional CAP scheme while preserving its low-complexity transceiver design. The S-CAP technique is proposed and investigated for systems employing the visible light communication technology. An analytical expression for the joint detection of the spatial and signal bits for the user equipment experiencing line-of-sight propagation (LOS) is derived and validated via simulation. The effects of the multipath propagation and user mobility on the bit-error-rate (BER) performance of the proposed S-CAP are also investigated. It is found that the BER performance of the S-CAP in LOS is dictated by the minimum of the channel gains hmin, the signal constellation points, and the channel gain dissimilarity, Δ|h|. The power factor imbalance (PFI) and multiple photodetectors (PDs) are then introduced to improve the performance and mitigate the channel impairments. The use of the PFI and PDs in LOS results in the signal-to-noise gain of 33.5 and 43 dB, respectively. The proposed scheme is thus a novel implementation of the CAP in a multiple-input–multiple-output system and demonstrates its potential as a suitable physical layer solution for the VLC technology.
关键词： multiple-input–multiple-output (MIMO),visible light communication (VLC),Carrierless amplitude and phase modulation (CAP),multipath propagation,spatial modulation (SM)
更新于2025-09-19 17:15:36
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Spectral-Efficient Reconstructed LACO-OFDM Transmission for Dimming Compatible Visible Light Communications
摘要： Dimming control is critical in practical visible light communication (VLC) systems to satisfy illumination demand. Upon exploiting multiple layers of asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM) signals for simultaneous transmission, layered ACO-OFDM (LACO-OFDM) constitutes a promising spectral-efficient modulation technique for VLC. However, dimming by integrating the industry-preferred pulse width modulation (PWM) to the LACO-OFDM scheme induces severe clipping noise due to the nonlinearity of LEDs. In this paper, we conceive a reconstructed LACO-OFDM (RLACO-OFDM) scheme incorporating the PWM technique for VLC to accommodate the dimming demands for indoor illumination, while maintaining a spectral-efficient communication link. Moreover, superior to its counterparts, the transmitted symbols in the RLACO-OFDM based VLC system can be readily recovered by a standard LACO-OFDM receiver while no additional detection of the PWM signal is required, which reduces the receiver complexity. Numerical results demonstrate that the proposed RLACO-OFDM is capable of realizing high spectral efficiency over a broad dimming range.
关键词： asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM),layered ACO-OFDM,pulse width modulation (PWM),Visible light communication (VLC),dimming control
更新于2025-09-19 17:15:36
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Energy Efficient Transceiver Design for NOMA VLC Downlinks with Finite-Alphabet Inputs
摘要： Non-orthogonal multiple access (NOMA) is considered as a promising technique in visible light communication (VLC) systems for performance enhancement. In order to improve the system’s energy ef?ciency, we carry out transceiver design for an NOMA VLC system. We develop an optimal power allocation scheme for the system based on ?nite-alphabet inputs, and we propose a joint detection and decoding (JDD) algorithm for signal detection. Comprehensive simulation results demonstrate that our proposed NOMA strategy can achieve signi?cant performance gains over the time division multiple access (TDMA) scheme, and our designed JDD algorithm outperforms the conventional successive interference cancellation (SIC) algorithm for NOMA.
关键词： visible light communication (VLC),?nite-alphabet inputs,joint detection and decoding (JDD),power allocation,non-orthogonal multiple access (NOMA)
更新于2025-09-19 17:15:36
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Spectral-Efficiency -Illumination Pareto Front for Energy Harvesting Enabled VLC Systems
摘要： The continuous improvement in optical energy harvesting devices motivates the development of visible light communication systems that utilize such available free energy. In this paper, an outdoor visible light communications (VLC) system is considered where a VLC base station sends data to multiple users that are capable of harvesting optical energy. The proposed VLC system serves multiple users using time division multiple access (TDMA) with unequal time and power allocation, which are allocated to achieve the system communications and illumination objectives. In an outdoor setup, the system lighting objective is to maximize the average illumination flux, while the communication design objective is to maximize the spectral efficiency (SE). A multiobjective optimization problem is formulated to obtain the Pareto front of the SE-illumination region. To this end, the marginal optimization problems are solved first using low complexity algorithms. Then, based on the proposed algorithms, a Karush-Kuhn-Tucker-based algorithm is developed to obtain an inner bound of the Pareto front for the SE-illumination tradeoff. The inner bound for the Pareto-front is shown to be close to the optimal Pareto-frontier via several simulation scenarios for different system parameters.
关键词： Pareto front,outdoor communication,illumination,multiobjective optimization,mass gathering events,spectral efficiency,energy harvesting,Visible light communication
更新于2025-09-19 17:13:59
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[IEEE 2018 International Conference on Recent Innovations in Electrical, Electronics & Communication Engineering (ICRIEECE) - Bhubaneswar, India (2018.7.27-2018.7.28)] 2018 International Conference on Recent Innovations in Electrical, Electronics & Communication Engineering (ICRIEECE) - Improvement of Uniformity of Illumination for Circular LED Arrangement in VLC System
摘要： Light emitting diode (LED) offers several advantageous properties that they can be used in many lighting applications. The optimal placement of LED lamps is very crucial for effective visible light communication (VLC). In this paper, different LED arrangements have been investigated and analyzed using MATLAB for estimating the illumination uniformity. To closely approximate the practical scenario, single bounce reflections from the walls has been considered for evaluating the results. The results show that the uniformity of illumination within the room significantly improves with the increase in the radius of the circular array of LEDs. The optimal arrangement of LEDs shows significantly better results than the other proposed arrangements.
关键词： visible light communication,Light emitting diode (LED),illuminance,uniformity
更新于2025-09-19 17:13:59
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Red-shift effect in multi-color LEDs based visible light communication
摘要： Visible light communication (VLC) is a short range wireless optical communication system that provides lighting and data transmission, simultaneously. Besides lighting, in order to obtain high data rates, color-shift keying (CSK) which modulates the intensity of light using multi-color light emitting diodes (LEDs) has been introduced in IEEE 802.15.7 VLC standard. In CSK-based VLC (VLC-CSK) systems, some parameters of LEDs such as junction temperature is affected by physical and operation conditions. Junction temperature variations change the power spectral density (PSD) of LEDs, which is known as red-shift effect. In this study, the red-shift effect is examined for the first-time in VLC-CSK systems. The obtained numerical results show that the red-shift effect may dramatically reduce the performance of optical communication system. To eliminate the negative effect of red-shift, an effective solution based on the power normalization is proposed at the receiver side.
关键词： Visible light communication (VLC),red-shift effect,color shift keying (CSK),light-emitting diode (LED)
更新于2025-09-19 17:13:59
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Optical polar based MIMO-OFDM with fully generalised index-spatial LED modulation
摘要： A novel efficient visible light communication (VLC) modulation technique teams as polar fully generalised index-spatial (PFGIS) modulation light emitting diode (LED) for the multi-input multi-output (MIMO) optical polar based OFDM (MIMO-POFDM) system is proposed here. The PFGIS is a spectrally efficient (SE) modulation scheme which introduces an elegant solution to tackle the OFDM signal shaping problem, moreover, the PFGIS improves the optical MIMO-OFDM system SE. In the PFGIS, the Cartesian complex OFDM signal is transformed to polar OFDM (POFDM). Then, the indices of the active LEDs are exploited to convey the POFDM signal components. While, the spatial position of the LEDs are exploited as a spatial modulation (SM). In the SM, the LEDs indices used for data transmission are changed from the case of two LEDs are selected to case where all/multiple LEDs are selected. Subsequently, the proposed system achievable data rate is linearly increased with the LEDs number. The PFGIS gives higher SE even with a lower LEDs number compared with the recently OFDM optical LED index modulation techniques. Simulation results confirm the efficiency of the proposed PFGIS in improving both the achievable data rate and the bit error rate compared with the up-to-date LED index modulation OFDM schemes.
关键词： multi-input multi-output (MIMO),spatial modulation (SM),visible light communication (VLC),polar fully generalised index-spatial (PFGIS) modulation,optical polar based OFDM (MIMO-POFDM),spectral efficiency (SE)
更新于2025-09-19 17:13:59