1,070 Results Found

PIN (positive intrinsic negative) photodiodes and analog-to-digital converters (ADC) are commonly used on visible light communication (VLC) receivers in order to retrieve the data on detected signals. In this paper, a visible light communication rece...

With the rapid development of visible light communication (VLC) technology, traditional modulation schemes can no longer meet the high demands for bandwidth efficiency and signal stability in complex application scenarios. In particular, in orthogona...

Infrared and visible image fusion-based object detection is critical for robust environmental perception under adverse conditions, yet existing methods still suffer from insufficient modeling of modality discrepancies and limited adaptivity in their...

The development and growth of Wireless Sensor Networks (WSNs) is significantly propelled by advances in Radio Frequency (RF) and Visible Light Communication (VLC) technologies. This paper endeavors to present a comprehensive review of the state-of-th...

Aiming at the problem of resource allocation strategies limiting the system transmission rate in indoor visible light communication and radio frequency (VLC/RF) systems, a new resource allocation method is proposed, and orthogonal frequency-division...

Colour-shift keying (CSK) is a visible light communication (VLC) modulation scheme used in the existing IEEE 802.15.7 standard. In CSK, information is transmitted by changing the light intensities of the RGB LEDs. In this work, a low-complexity VLC s...

It is well known that modern wireless communications systems need linear, wide bandwidth, efficient Radio Frequency Power Amplifiers (RFPAs). However, conventional configurations of RFPAs based on Class A, Class B, and Class AB exhibit extremely low...

In order to increase transmission capacity, multiplexing schemes in different physical dimensions, including time, frequency, modulation quadrature, polarization, and space, can be employed. In this work, we propose and demonstrate a red color laser-...

Visible light communications (VLC) are an emerging technology that is increasingly demonstrating its ability to provide wireless communications in areas where radio frequency (RF) technology might have some limitations. Therefore, VLC systems offer p...

In order to achieve high-capacity visible light communication (VLC), five dimensions in physics, including frequency, time, quadrature modulation, space, and polarization can be utilized. Orthogonality should be maintained in order to reduce the cros...

In this study, we theoretically study the optical bistability (OB) of reflected light beams at visible light frequencies by using a Kretschmann–Raether (KR) configuration where double-layer MoS₂ is inserted. This OB phenomenon results from the...

We demonstrate a discretely tunable multiwavelength visible laser through second harmonic generation (SHG) and sum frequency generation (SFG) of multiorder Stokes lasers generated from an external Raman laser oscillator. The Raman laser oscillator, d...

In order to improve the spatial resolution of a one-dimensional aperture synthesis (1-D AS) radiometer without increasing the size of the antenna array, the method of visibility extension (VE) is proposed in this article. In the VE method, prior info...

In video pipelines, document content in recorded lectures, surveillance footage, and broadcasted materials is often overlaid with persistent visible watermarks. Such overlays greatly reduce the readability of document images and interfere with downst...

Visible–infrared person re-identification (VI-ReID) aims to minimize the modality gaps of pedestrian images across different modalities. Existing methods primarily focus on extracting cross-modality features from the spatial domain, which often...

Negative refraction of nanolight (e.g., polaritons, hybrid light, and matter excitation) provides a promising building block for nanophotonics, as it paves the way for developing cutting-edge nanoscale applications, such as super-resolution and subwa...

A new visible light communication (VLC) system is proposed for localization in underground mining. Existent systems, such as global positioning system (GPS) and systems based on mobile communication, are generally not useful in underground mining. Th...

The Environmental Protection Administration of Taiwan’s Executive Yuan has set up many air quality monitoring stations to monitor air pollution in the environment. The current weather forecast also includes information used to predict air pollution....

In indoor visible light communication (VLC) and visible light positioning (VLP) systems, the performance of conventional orthogonal frequency-division multiplexing (OFDM) schemes is often compromised due to the nonlinear characteristics and limited m...

Nonlinear effects have been restricting the development of high-speed visible light communication (VLC) systems. Neural network (NN) has become an effective means to alleviate the nonlinearity of a VLC system due to its powerful ability to fit compli...

Based on the decorrelation calculation of diffusion ultrasound in time-frequency domain, this paper discusses the repeatability and potential significance of Disturbance Sensitive Zone (DSZ) in time-frequency domain. The experimental study of Barely...

With the development of light emitting diode (LED) lighting technology and its wide applications, visible light communication (VLC) technology has also seen significant advancements. VLC is regarded as a supplementary technology to radio frequency (R...

Different from the radio frequency bipolar complex signalling, LED-based visible light communication (LED-VLC) meets the non-negativity requirement by adding a bias component (BC) to a bipolar real-valued signal. Although many people know that there...

Both light emitting diode (LED) characteristics for illumination and communication simultaneously have made visible light communication-orthogonal frequency division multiplexing (VLC-OFDM) a strong competitive to radio frequency (RF). In this junctu...

Perfect metamaterial absorber (PMA) is an attractive optical wavelength absorber with potential solar energy and photovoltaic applications. Perfect metamaterials used as solar cells can improve efficiency by amplifying incident solar waves on the PMA...

This paper proposes a tree-based regression model for hybrid channel estimation in wireless sensor networks (WSNs) in generalized frequency division multiplexing (GFDM) over both visible light communication (VLC) and radio frequency (RF) links. The h...

The design of solid-state lighting is vital, as numerous metrics are involved in their exact positioning, and as it is utilized in various processes, ranging from intelligent buildings to the internet of things (IoT). This work aims to determine the...

Indoor low-power positioning systems have received much attention, and visible light positioning (VLP) shows great potential for its high accuracy and low power consumption. However, VLP also exhibits some limitations like small coverage area and the...

In this paper, we propose and experimentally demonstrate an orthogonal subblock division multiple access (OSDMA) scheme for orthogonal frequency division multiplexing with index modulation (OFDM-IM)-based multi-user visible light communication (MU-VL...

Linear programming was used to assess the ability of polarized infrared absorption, Raman scattering, and visible–infrared sum-frequency generation to correctly identify the composition of a mixture of molecules adsorbed onto a surface in four...

Embankment piping and leakage are primary causes of flood control infrastructure failure, accounting for more than 90% of embankment failures worldwide and posing significant threats to public safety and economic stability. Current manual inspection...

In order to improve the spectral efficiency (SE) as well as the receiver performance of band-limited visible light communications (VLCs), two orthogonal frequency division multiplexing (OFDM)-based quadrature generalized multiple-input multiple-outpu...

The electro-optic output of light-emitting diodes commonly used in visible light communication systems is generally nonlinear in nature. It is particularly problematic when using advanced modulation formats, such as orthogonal frequency-division mult...

An optimized design of photodetectors and antennas for Förster Resonance Energy Transfer (FRET)-based glucose biosensing in endoscopic capsules is presented. The compact antenna design is tailored for the visible optical frequencies (~526 THz) a...

This paper investigates handover in hybrid visible light communication (VLC)/radio frequency (RF) networks. In such a network, mobile users are prone to experience frequent handovers (FHOs). To this end, we propose a collaborative online learning-bas...

In visible light communications (VLC), dimming control constitutes an indispensable technique to comply with various illumination necessities and with different energy consumption constraints. Therefore, a novel dimming compatible hybrid optical orth...

Non-orthogonal multiple access (NOMA) is deemed to be a prospective multiple access technology of the next generation. However, in visible light communication (VLC), when advanced hybrid optical orthogonal frequency division multiplexing (O-OFDM), su...

Given the tunability of their optical properties over the UV–Visible–Near IR spectral range, ligand-capped quantum dots (QDs) are employed for the design of optical biosensors with low detection threshold. Thanks to non-linear optical spectroscopies,...

In this letter, we present the first attempt of active light-emitting diode (LED) indexes estimating for the generalized LED index modulation optical orthogonal frequency-division multiplexing (GLIM-OFDM) in visible light communication (VLC) system b...

The expectation for communication systems beyond 5G/6G is to provide high reliability, high throughput, low latency, and high energy efficiency services. The integration between systems based on radio frequency (RF) and visible light communication (V...

Conventional optical orthogonal frequency division multiplexing (OFDM) schemes, such as adaptively biased optical OFDM (ABO-OFDM) and hybrid asymmetrically clipped optical OFDM (HACO-OFDM), are unable to tap all the resources of the subcarriers and o...

Filtered orthogonal frequency division multiplexing (F-OFDM), employed in visible light communication (VLC) systems, has been considered a promising technique for overcoming OFDM’s large out-of-band emissions and thus reducing bandwidth efficie...

To study the potential application of metasurfaces in lens technology, we propose a dendritic meta-molecule surface (also referred to as a dendritic metasurface) and realize the focusing effect in the visible spectrum through simulations and experime...

Visible light communication (VLC) is an emerging mode of wireless communication that supports both illumination and communication. One essential function of VLC systems is the dimming control, which requires a sensitive receiver for low-light conditi...

Visible light communication (VLC) channel quality depends on line-of-sight (LoS) transmission, which cannot guarantee continuous transmission due to interruptions caused by blockage and user mobility. Thus, integrating VLC with radio frequency (RF) s...

Billions of U.S. dollars of basic and applied research funding have been invested during the last few years in ideas proposing inverse concepts. The photonics market could not make an exception to this global trend, and thus, several agenda-setting r...

The key difference between visible light communication (VLC) and radio frequency (RF) communication is the former’s line-of-sight (LOS) transmission nature, and hence a relay node has to be adopted for VLC to extend its coverage. Physical-layer...

Here, we propose an optical bistable device structure with a few layers of graphene oxide integrated in the metal-dielectric-metal based asymmetric nanocavity. Through the light confinement in the nanocavity, the third order nonlinear absorption of g...

Atmospheric visibility is an important indicator that reflects the transparency of the atmosphere and characterizes the air quality, so it is of great significance to study the long-term change in visibility. This paper is based on the global surface...

The current deep learning-based image fusion methods can not sufficiently learn the features of images in a wide frequency range. Therefore, we proposed IFormerFusion, which is based on the Inception Transformer and cross-domain frequency fusion. To...