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Emerging Wireless Communication
Published in Rebecca Lee Hammons, Ronald J. Kovac, Fundamentals of Internet of Things for Non-Engineers, 2019
Lauren McNally, Aaron Khoury, Jerry Walker, Stephan Jones
Li-Fi is a technique to help move to higher frequencies using light wave communications on the electromagnetic spectrum. Li-Fi as an emerging technology within the wireless space that will help to increase the speed of wireless communication through light. Li-Fi utilizes light-emitting diodes (LEDs) and its modulation techniques: single carrier (e.g., pulse amplitude modulation, pulse width modulation, and on–off keying) and multi carrier (e.g., orthogonal frequency division multiplexing), Li-Fi can cover more of the spectrum [6]. Being able to utilize LEDs instead of radio frequencies will cut down interference. LED lights are high speed transmitters of data over reduced transceiver units.
Secure sound and data communication via Li-Fi
Published in Sabyasachi Pramanik, Anand Sharma, Surbhi Bhatia, Dac-Nhuong Le, An Interdisciplinary Approach to Modern Network Security, 2022
Vibha Ojha, Anand Sharma, Suneet Gupta
Li-Fi works based on visible light communication technology using LED bulbs. Many indoor premises already have LED bulbs for lighting purposes; the same source of light can be used as a means of communication to transmit data. It is possible to adjust Li-Fi bulbs so that the light is barely visible to the human eye when there is no need for light.
Limos—Live Patient Monitoring System
Published in Saravanan Krishnan, Ramesh Kesavan, B. Surendiran, G. S. Mahalakshmi, Handbook of Artificial Intelligence in Biomedical Engineering, 2021
T. Ananth Kumar, S. Arunmozhi Selvi, R.S. Rajesh, P. Sivananaintha Perumal, J. Stalin
Li-Fi is a wireless technology that uses visible light as the communication medium of standard IEEE 802.15.7. Li-Fi was proposed by Harald Haas in 2011 (Li-Fi, 2019). Li-Fi refers to an innovative wireless system of visible light communication (VLC) technology. The VLC technology can deliver bidirectional communication with high-speed data rates and networked mobile communication by using LED as the light source. The LED transmits the binary form of data in the form of light pulses and thus is an optical wireless communication (OWC) communication (Li-Fi, 2019). Li-Fi technology is also based on a visible-light wireless communication system that lies between the violet color (800 THz) and red color (400 THz). The Li-Fi uses the optical spectrum that is visible light part of the electromagnetic spectrum, whereas Wi-Fi uses RF of the electromagnetic spectrum. It uses fast strokes of LED light to transmit data, as it cannot be noticed by the normal human eye. It includes the visible light spectrum to transmit the information. VLCs features are providing wide bandwidth, that is, the optical spectrum guarantees more than 10,000 times better bandwidth than the convention of the harmful RF frequencies. The LED lights work rapidly for transmitting the binary data by switching the LED on and off because it has no interfering light frequencies like that of the radio frequencies in Wi-Fi. In Li-Fi, the LED in the transmitter is connected to the data network (Internet through the modern) and the receiver (photodetector/solar panel) on the receiving end, which obtains the data as light gesture and decrypts the information and then displays on the device connected to the receiver (An Internet of Light, 2014). In the early stage, the data transfer speed was 15 Mbps. Later, many commercial luminaries helped to increase the speed of Li-Fi up to almost 10 Gbps, which has overcome the speed of 802.11.ad. IEEE 802.15.7 is a specific wireless network standard that defines the working of the physical and data link layer, which is a media access layer that defines the working of the mobility of optical transmission and its coexistence with the present architecture. There are many features of Li-Fi related to modulation, illumination, and dimming scheme, which is the first concern (Wikipedia, 2016). In December 2017, Velmenn introduced an advanced Li-Fi USB adapter for its use in the communication of USB components and Li-Fi-enabled LED lights (LaMonica et al., 2019). This technology that is of a light form of data transmission is highly radiation-free and plays an energetic role in the medical field. The advantages include efficiency, availability, and security (Rohner et al., 2015).
Investigation of Energy Generation Potential of Solar Panels Placed as Shutters for Windows in Residential
Published in Electric Power Components and Systems, 2023
It is also possible to use the LED strips used for the illumination of the sample flat within the scope of the study for the purpose of providing wireless communication within the flat [57]. Wireless communication with visible light (380-750 nm) has become a rapidly developing and preferred method in recent years, and its abbreviation is known as Li-Fi [58]. In the Li-Fi wireless communication method, the data sent by a visible light source that flashes at high frequencies that the eye cannot detect is detected and processed by a photodiode that is also sensitive to visible light [59]. Thus, both lighting and wireless data communication can be realized with the visible light source. There are significant advantages in Li-Fi wireless communication using LEDs [60]. That can be said that using the Li-Fi method for data communication, especially in indoor environments, is safer for human health than Wi-Fi, RF, IR, Bluetooth etc. methods [61]. In this respect, within the scope of the study, the idea that LED strips fed directly with electrical energy generated from solar energy can also be used in data communication has been examined. In other studies conducted with the Li-Fi method, the visible light source used in data transfer is generally concentrated at a certain point [59]. Since the LED strips are used for the illumination of the sample flat, the visible light is diffusely reflected along all the walls. This allows for easier and uninterrupted wireless data communication throughout the sample flat. For the Li-Fi communication system test, the instantaneous voltage, instantaneous current and ambient temperature of the batteries were selected as the transmitted data. These data are measured by the support of a microcontroller (PIC16F877). The measured data is transferred to the Li-Fi receiver with the LEDs driven over the Mosfets connected to the same microcontroller output. The temperature of the environment where the battery pack is located was measured via DS18B20 temperature sensor. The data transmitted by the (visible light source) LEDs are detected by the photodiode (BPW21) on a Li-Fi receiver then sampled and processed by another microcontroller (PIC16F877) and reflected on an LCD screen. The block diagram of Li-Fi wireless data communication is given in Figure 7.