Light Fidelity Research Articles

Traffic Management with Deployment of Li-Fi Technology

Light Fidelity or commonly known as Li-fi, is an emerging technology that works on the principle of using light as a medium for transferring signals. It is bidirectional and is fully networked wireless communication that focuses on the use of light from light-emitting diodes (LEDs). The system is affluent and can provide connectivity within a larger area with more security, higher data rates and high-speed as compared to Wi-Fi. Apart from that, it relies on the use of visible light communication or infra-red and near-ultraviolet spectrum majorly working on the idea of switching bulbs on and off within nanoseconds. The paper consists of vivid insights about the use of Li-fi as a solution to the excessive traffic congestion in roadways. The paper is further divided into prominent sections that deal in providing an accurate idea about the working and implication of Li-fi technology in the current scenario. Moreover, the paper also proposes various technical standards and modulation that are and will be followed by Li-fi technologies, thereby focusing on its future implication. Apart from that, the main aim of designing the system is to limit traffic congestion and thus, reduce the increasing number of road accident in the present times.

Visible Light Communication Design and Implementation

There have been many recent technological developments in wireless communication and exponential growth in demand such as lack of sufficient space, bandwidth restriction, and interference. Radio waves have been used to interact conventionally, and there is a growing obligation to look for new technology because of this challenge. Therefore, contact using light is a very motivating vision of wireless communication to solve most challenge. LiFi (Light Fidelity) is the modern contact approach. Visible Light Communication (VLC) simultaneously addresses enlightenment and communication problems. In this paper, a VLC concept was conceived and implemented.

Plasmonic Antenna Embedded Chalcogenide MZI Circuit for Ultra-high Density Up- and Downlink Transmission

A unique device is proposed for ultra-high density up- and downlink transmission. The device comprises of the chalcogenide Mach–Zehnder interferometer (MZI) and panda ring resonator with silver bars at the center microring at the upper and lower parts of the MZI. The device is operative based on the space–time function where the input space (soliton) via the input port multiplexes with time at the add port of the device with a wavelength bandwidth of 1.50–3.50 µm and the frequency bandwidth of 85–250 THz. The WGM is observed at the upper (uplink) and lower (downlink) center microring with suitable parameters. The silver bars at the center microring form the dipole oscillation, where the uplink and downlink plasmonic antennas have the directivity 18.68 and 13.27, and gain is 9.34 and 6.64, respectively. The light fidelity (LiFi uplink and downlink) employs the wavelength spectrum while the wireless fidelity (WiFi uplink and downlink) employs the frequency spectrum. The LiFi uplink and downlink have an optimum wavelength of 2.30 µm and 2.27 µm, respectively, while the WiFi uplink and downlink have an optimum frequency of 130 THz and 132 THz. For the transmission signal, the bit rate of 28 Pbits−1 is achieved. The bit error rate (BER) value of 0.36 is obtained which indicates the system performance. Low BER value indicates high system performance. The device can be employed for the coverage of the light-wave and microwave wavelength link for 6G communication, where AI (artificial intelligence), 3D communication, code encryption, and secured transmission can be applied.

Integrating Metamaterial Antenna Node and LiFi for Privacy Preserving Intelligent COVID-19 Hospital Patient Management.

Light fidelity (LiFi) and wireless fidelity (WiFi) can be applied with the same network under the different constraints, which is suitable for COVID-19 surveillance in hospitals. The LiFi network is a high-capacity and security platform. A COVID-19 surveillance system using LiFi is proposed, which consists of two switching modes: communication and surveillance. Firstly, the communication targets are to accommodate the electromagnetic interference (EMI) immunity and high-capacity and security data transmission, where secondly the COVID-19 surveillance can be applied. In operation, the up and downlink system uses a metamaterial antenna embedded by Mach Zehnder interferometer (MZI). An antenna consists of silver bars embedded at the microring center with two-phase modulators at its sides. The entangled source namely a dark soliton is applied to form the transmission, where the information security based on quantum cryptography can be managed. By using the suitable parameters, the whispering gallery modes (WGMs) are generated and the up and downlink nodes are formed. The input information is multiplexed with time to form the multiplexed signals, where the big data transmission (40 Pbit {mathrm{s}}^{-1}) can be employed. By using the surveillance mode, the plasmonic antenna can be applied for temperature and electric force sensors, which can offer the disinfectant spray and temperature sensor for COVID-19 applications. The optimum plasma force sensitivity is 0.16 N kg−1 mW−1. The center frequencies of 191.48 THz and 199.41 THz are obtained for uplink and downlink antennas, respectively. The optimum temperature sensitivity is 0.05 rads−1 °C−1. In conclusion, the novelty of proposed work is that the integrated sensor circuits are employed for COVID-19 surveillance in the hospital. The fuzzy-based system is designed for critical patient monitoring alert using this surveillance and management inside the hospital for COVID-19 patients.

Remote Tracking Gas Molecular via the Standalone-Like Nanosensor-Based Tele-Monitoring System

HighlightsA standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way is created;Metal–organic framework-derived hollow polyhedral ZnO was successfully synthesized, allowing the created smart device to be highly selective and to sensitively track the variation of NO2 concentration;A novel photoluminescence-enhanced Li-Fi telecommunication technique is proposed, offering the created smart device with the capability of long distance wireless communication.Remote tracking the variation of air quality in an effective way will be highly helpful to decrease the health risk of human short- and long-term exposures to air pollution. However, high power consumption and poor sensing performance remain the concerned issues, thereby limiting the scale-up in deploying air quality tracking networks. Herein, we report a standalone-like smart device that can remotely track the variation of air pollutants in a power-saving way. Brevity, the created smart device demonstrated satisfactory selectivity (against six kinds of representative exhaust gases or air pollutants), desirable response magnitude (164–100 ppm), and acceptable response/recovery rate (52.0/50.5 s), as well as linear response relationship to NO2. After aging for 2 weeks, the created device exhibited relatively stable sensing performance more than 3 months. Moreover, a photoluminescence-enhanced light fidelity (Li-Fi) telecommunication technique is proposed and the Li-Fi communication distance is significantly extended. Conclusively, our reported standalone-like smart device would sever as a powerful sensing platform to construct high-performance and low-power consumption air quality wireless sensor networks and to prevent air pollutant-induced diseases via a more effective and low-cost approach.

Dynamic ambient HetNet for hybrid data communication and transmission in IoT networks

In this manuscript, the Dynamic ambient HetNet for hybrid data communication and transmission in IoT networks is proposed. The lodging of colossal devices and their linkages in and beyond 5th generations (5G) has obtained a great deal of studies from academia and business. In the macro hotspot field, the uses of emerging Device-to-device (D2D), Light Fidelity (LiFi), Unmanned Aerial Vehicle (UAV) and Drones can’t simply cross the paths of transient network support prerequisites. Environmental interaction is an optional way to efficiently reduce this problem through the provision of urgent connections among limited-power servers. In addition, the effectiveness of transmission relies on parameters and range from factors like signal form, Radio frequency (RF) origin and the atmosphere, i.e. indoor or outdoor. The proposed Dynamic Ambient HetNet architecture both indoors and outdoors, where a source node is connected to the target node via radio frequency-powered relays to increases network coverage and enhance the efficiency of mobile devices either within the macro hot spot region or during the disaster area like hurricanes. This method can exploit the Wireless interweave down-convert up-convert protocol with energy-collection capacity for simultaneous information and power transfer. During the propagation from the origin node, radio frequency-powered relay can monitor hybrid data broadcasts, owing to its full duplex features. The efficiency assessment in MATLAB demonstrates the traditional models for radio frequency relay in hybrid communication. Moreover, we endow with the challenges in relation to the ambient backscatter communication network. The experimental results proved that the proposed method is better in terms of power factor and throughput gives 90%, ratio for the uplink and down link in terms of cell load has obtained 75%, and packet throughput in terms of speed has the value of 93%.

LiFi-based smart systems for industrial monitoring

Light fidelity (Li-Fi) is an unfolding technology which can be used to transfer data through light. It is a complete transformation to the world of wireless data transfer. Harald Haas from the University of Edinburgh, UK termed and introduced light fidelity to world through the global talk show in which he demonstrated of a Li-Fi prototype at the TED Global Conference in Edinburgh on 12 July 2011. Challenging the pre-existing data transfer model namely the wireless fidelity (Wi-Fi) on various parameters such as speed, safety, reliability eco-friendliness and efficiency. The light emitting diode in a Li-Fi system is the source of data transfer utilising visible light as medium of communication. This can provide greater download capacity in comparison to the existing wired or wireless networks due to higher bandwidth of light. With such high potential every electronic day to day use commodity that has role of light over it can be thought of to be used as an internet accesses point. Since it cannot penetrate through walls, they have short range but are highly secure in the confinement of the surrounding in comparison to Wi-Fi and overcome the radio frequency bandwidth availability issues in the near future.

On-The-Move Measurement Analysis for Ka-Band High Throughput Satellite and LiFi Communication Networks in Tropical Region

With the point in evaluating the performance of the On-the-Move (OTM) Satellite Communication and Light Fidelity (SatCom-LiFi), an extensive study of measurement has been conducted to give a wide vision of the SatCom-LiFi potential under a tropical region. As the interest for OTM network connectivity to offload the C-band capacity arises due to frequency spectrum scarcity, satellite networks offer to balance topographical requirements under tropical environment as the Next Generation Networks (NGN) trend for OTM communication system solutions. To date, mobile satellite terminal propagation model was carried out at temperate regions where further experimental measurement is needed under the OTM scenario in tropical region. This paper discusses on the areas where there are limited real-time data under the OTM scenario (e.g. rain attenuation, power arch) at Ka-band frequency. Integration infers, to be specific, the use of new elements capable in providing performance analysis of all systems involved and to take possible decision, in determining the need for a technically feasible solution. Measurement results reveal that, throughput data rate of 15 Mbps were able to be delivered for more than 80% of the time under the speed of 150 km/h with shielded mesh antenna. In addition to that, this paper reveals the favorable circumstances and inadequacies of OTM network quality, in which the measurement presented plays an important role for future researchers in distinguishing highly accurate predictions.

Reconfigurable Intelligent Surface Aided Multi-User Communications: State-of-the-Art Techniques and Open Issues

Reconfigurable intelligent surface (RIS)-aided communication is considered as an exciting research topic in academic and industrial communities since it provides an emerging affordable solution to achieve high quality and secure next-generation wireless systems. Especially, the deployment of RIS in multi-user wireless networks promises to reduce system hardware costs, signal processing complexity, as well as energy consumption due to small size, lightweight and ability to actively shape the wireless propagation environment. Further, by realizing a cost-effective radio environment, RIS-aided communication can be implemented to be an appealing technology for future integration with other emerging wireless applications and communication systems. Despite the positive appeal, RISs face new challenges that hinder integrating efficiently into wireless networks, such as network secrecy performance and system sum-rates, as well as achieving efficient deployment design in highly dynamic and time-varying wireless environments. To this end, we overview recent state-of-the-art techniques to address the above issues faced in the integration of RISs with various emerging multi-user communication techniques, such as Unmanned Aerial Vehicles (UAVs), Non-Orthogonal Multiple Access (NOMA), Millimeter Wave (mmWave) and Terahertz (THz) communications, Physical Layer Security (PLS), massive antennas, and Simultaneous Wireless Information and Power Transfer (SWIPT). Finally, we highlight promising future research directions of RIS-aided communication in Cell-Free Massive Multiple-Input-Multiple-Output (MIMO) systems, Rate-Splitting Multiple Access (RSMA), Light Fidelity (LiFi), and Cognitive Radio (CR) systems.

Design and Analysis of Light Fidelity Network for Indoor Wireless Connectivity

In the world of 20 billion connected devices, the data centers are just a drop in the ocean for the total energy consumption compared to the wireless access that is required for them. In the past years, it never became possible to obtain unprecedented bandwidth, to keep our data safe and repurpose the energy that we use for illumination to provide wireless communication, but now in the modern era, Light Fidelity (Li-Fi) can offer these things and much more. LiFi points towards high-speed, bi-directional, and networked wireless communications with the assistance of light. It offers users an almost similar experience as traditional wireless communications except using the light spectrum. With LiFi, a world connected by light has become an unbelievable reality. The design and functionality of the previous models are targeted to provide wireless communication but, to prove better quality results, an entire system is checked, and a new model is put forward. In this research study, the entire system is examined and tested on different values with various transmitting angles, data rates, distances, frequencies, the responsivity of PIN diodes to ensure the accuracy and best possible results are achieved. Testing of numerous ambient sources and modulation schemes aided in the success of this advanced technology. Different filters, transmitted pulses, modulation schemes, and angles are also changed and analyzed to study the behavior of LiFi thoroughly, which helped to attain a high-quality factor (Q-factor). The objectives of decline in Bit error rate (BER), increase in data rate, and quality signal are successfully achieved in the conclusion of this model. The research article is not only optimized but also has advanced features which mainly helped in gaining maximum results and goals behind this project.

Hybrid LiFi and WiFi Networks: A Survey

In order to tackle the rapidly growing number of mobile devices and their expanding demands for Internet services, network convergence is envisaged to integrate different technology domains. For indoor wireless communications, one promising approach is to coordinate light fidelity (LiFi) and wireless fidelity (WiFi), namely hybrid LiFi and WiFi networks (HLWNets). This hybrid network combines the high-speed data transmission of LiFi and the ubiquitous coverage of WiFi. In this article, we present a survey-style introduction to HLWNets, starting with a framework of system design in the aspects of network architectures, cell deployments, multiple access and modulation schemes, illumination requirements and backhaul. Key performance metrics and recent achievements are then reviewed to demonstrate the superiority of HLWNets against stand-alone networks. Further, the unique challenges facing HLWNets are elaborated on key research topics including user behavior modeling, interference management, handover and load balancing. Moreover, the potential of HLWNets in the application areas is presented, exemplified by indoor positioning and physical layer security. Finally, the challenges and future research directions are discussed.

A novel binary encryption algorithm for navigation control of robotic vehicles through visible light communication

Scarcity in radio frequency spectrum has increased the demands for alternate sources of communication medium out which visible light communication (VLC) is quite notable. VLC works by exploiting the abundance in availability of light as an effective means of communication medium. This principle known as Li-Fi or light fidelity conveys information in the form of light pulses modulated with information signals collected by a suitable detector. The objective of this research article is to ensure a secured wireless communication channel using light as the medium. Communication through a wireless medium necessitates appropriate security mechanisms for data being transmitted. In the proposed work, a binary encryption algorithm (BEA) has been tested in a multi-node environment using a mobile robotic vehicle. Data transmitted through the medium contain instructions to navigate the motion of the vehicle. The algorithm simple yet powerful with precise encryption observed from the results.

Li-Fi technology: A Era of New Data Transmission

The main focus of this paper is to clarify the concept and working of Li-Fi technology. In present era, wireless communication plays an important role in day to day life. Wifi is the most used wireless technology which transmits data through radio frequencies. However, during multiple accesses WiFi is facing many challenges related to speed, security and efficiency. Also, WiFI emits radio waves which are harmful in hospitals for patients and cannot be used in underground communication and airplanes. These limitations of WiFi are overcome by Li-Fi technology. The term Li-Fi stands for Light Fidelity which uses visible light communication (VLC) to transfer data at high speed. In this paper, a detailed study on Li-Fi technology, its working and future scope is discussed.

Li-Fi delivering broad band and multimedia content under dimming in train

This paper focuses in delivering broad band and media content to numerous users while traveling in the train through light fidelity (Li-Fi), an innovative technology under Visible Light Communication (VLC). In our daily life, there is increasing traffic request for open Radio Frequency (RF) to support the users. In RF, even recurrence and spatial reuse of spectrum not able to support in conveying broad band and multimedia content to the internet users. For high-capacity mobile data networks, the VLC can balance the RF-based mobile communication systems. VLC conserves energy through dimming. Dimmed Light Emitting Diode (LED) luminaries provide visual comfort with appropriate optics while accessing internet. In the proposed work, LED dimming is achieved through digital dimming modulation technique, Variable Delta Sigma Modulation. The broad band and multimedia content can be delivered faster through Reverse Polarity Optical Orthogonal Frequency Division Multiplexing modulator to the internet users under dimming with better bit error rate and bit rate.

Nanosensor-Based Flexible Electronic Assisted with Light Fidelity Communicating Technology for Volatolomics-Based Telemedicine.

Telemedicine provides an attractive vision for tele-monitoring human health conditions and, thus, offers the opportunity for timely preventing chronic disease. A key limitation of promoting telemedicine in clinic application is the lack of a noninvasive med-tech and effective monitoring platform, which should be wearable and capable of high-performance tele-monitoring of health risk. Here we proposed a volatolomics-based telemedicine for continuously and noninvasively assessing human health status through continuously tracking the variation of volatile markers derived from human breath or skin. Particularly, a nanosensor-based flexible electronic was specifically designed to serve as a powerful platform for implementing the proposed cost-effective healthcare. An all-flexible and highly packed makeup (all functional units were integrated in a 2*2*0.19 cm3 plate) enables an electronic, compact configuration and the capability of resisting negative impact derived from customers' daily movement. Notably, the nanosensor-based electronic demonstrates high specificity, quick response rate (t90% = 4.5 s), and desirable low detection limit (down to 0.117 ppm) in continuous tele-monitoring chronic-disease-related volatile marker (e.g., acetone). Assisted by the power saved light fidelity (Li-Fi) communicating technology, a clinic proof on the specifically designed electronic for noninvasively and uninterrupted assessing potential health risk (e.g., diabetics) is successfully implemented, with the accuracy of around 81%. A further increase in the accuracy of prewarning is predicted by excluding the impact of individual differences such as the gender, age, and smoking status of the customer. These promising pilot results indicate a bright future for the tailor-made nanosensing-device-supported volatolomics-based telemedicine in preventing chronic diseases and increasing patients' survival rate.

Vehicle to vehicle data transfer and communication using LI-FI technology

The concept of Vehicle to vehicle data transmission refers to the communication between two vehicles that ensures safety and security of the vehicle occupants. In this project, we present the designs and results of a prototype using the light fidelity (Li-Fi) technology, which is the latest technology that was developed in the last few years, which needs some systematic inquiry on its sustainability for use in the vehicles. Vehicle to vehicle communication is the most effective solution that is available in order to reduce the road accidents. The proposed use of this Li-Fi technology comprises mainly the light- emitting diode (LED) bulbs as the means of connectivity that functions by sending data through the light spectrum as an optical wireless medium for the signal propagation. In fact, the usage of these light emitting diode (LED) eliminates the need of a complex wireless networks and protocols. The designed system ensures a highly-reliable communication between the vehicles so that accidents can be reduced to a greater extent.

Perovskite light-emitting/detecting bifunctional fibres for wearable LiFi communication

Light fidelity (LiFi), which is emerging as a compelling technology paradigm shifting the common means of high-capacity wireless communication technologies, requires wearable and full-duplex compact design because of its great significance in smart wearables as well as the ‘Internet of Things’. However, the construction of the key component of wearable full-duplex LiFi, light-emitting/detecting bifunctional fibres, is still challenging because of the conflicting process between carrier separation and recombination, as well as the highly dynamic film-forming process. Here, we demonstrate light-emitting/detecting bifunctional fibres enabled by perovskite QDs with hybrid components. The hybrid perovskite inks endow fibres with super-smooth QD films. This, combined with the small exciton binding energy and high carrier mobility of perovskite QDs, enables successful integration of electroluminescence and photodetection into monofilaments. The bifunctional fibres possess the narrowest electroluminescence full width at half maximum of ~19 nm and, more importantly, the capability for simultaneously transmitting and receiving information. The successful fabrication of narrow emission full-duplex LiFi fibres paves the way for the fabrication and integration of low crosstalk interoperable smart wearables.

Smart Handover for Hybrid LiFi and WiFi Networks

This work investigates handover in hybrid light fidelity (LiFi) and wireless fidelity (WiFi) networks (HLWNets). In such a network, the handover process becomes challenging due to two main factors: i) the relatively short coverage range of a single access point (AP), and ii) the largely overlapping coverage areas of different networks. As a result, HLWNets are susceptible to frequent handovers. To reduce the handover rate, the concept of handover skipping (HS) was introduced, which enables handovers between non-adjacent APs. However, conventional HS methods rely on knowledge about the user's trajectory, which is not readily available at the AP. In this paper, a novel HS scheme is proposed on the basis of reference signal received power (RSRP) and its rate of change, with an adaptive network preference adopted. Since RSRP is commonly used in the existing handover schemes, the proposed method requires no additional signalling between the user and the AP. Simulation results show that the new method can effectively reduce unnecessary handovers, especially those between LiFi and WiFi. Compared to the standard and trajectory-based handover schemes, the proposed method improves network throughput by up to about 120% and 30%, respectively.

An Experimental Assessment of LiFi Data Communication

In this paper, two functional light fidelity real-time testbeds implemented on custom Light fidelity (LiFi) kits are presented. This paper evaluates the use of LiFi technology over differ­ent distances and angular placement of illuminating devices and endpoint transceivers with connectivity locally and to the internet. The objective is to determine if distance or angular positioning in LiFi influence speeds or not. Finally, it aims to contribute to knowledge in the LiFi communication domain. We were limited to developing a customized testbed for wireless optical communication by accessing data in the physical layer via photons. In a lateral dis­tance and angular position, we examined the performance of a laptop with LiFi activated by a 3730 lm LED. The setup evaluated the performance of our design in a downlink and uplink scenario where the transmitter was embedded in the main LED unit and the laptop was used as a photoreceiver. The data rate/kbps, the lateral distance / m, and the angle displacement / θ° were the comparison metrics. The results of the tests show that the transmission of LiFi is not influenced by distance and angular positioning for both downloads and uploads over different distances.

Transmission of the Numeric Data Using Light Fidelity Technology

Transmission of the Numeric Data Using Light Fidelity Technology