Radio Frequency Vs. Light Communication
The number of devices accessing mobile network is increasing rapidly which is directly proportional to the mobile data traffic. Unfortunately, the RF spectrum is suffering to a great extent due to the high demand resulting in poor performance and high interference. With RF communication, comes the following problems:
- Interference with other communication & navigation systems
- Disruptions due to the bandwidth limitations
- High congestion leading to low speed or inefficiency
- Security issues as RF waves can easily penetrate through walls
- Health hazards as more RF waves can be dangerous
Light Communications, on the other hand, have high bandwidth and are immune to any interference from electromagnetic sources. The light spectrum is globally unlicensed and can be utilised to communicate freely with low power consumption and the cost-effective deployment of the connectivity infrastructure. LC provides wireless data connectivity in spaces where the use of RF is unwanted or not secure or not possible. Isn’t it impressive?
Want high-speed internet to transfer your data? All you need is light!
In ancient times, the light was used to convey messages using methods such as fire and smoke signals. The Roman used polished metallic plates for sunlight reflection to carry out long-distance signaling.
And then, inventions in the field of science and technology happened. We got to discover and study things closely which broadened our scope of research work.
Talking about light, we ought to explain what’s Electromagnetic Spectrum. It is the range of frequencies of electromagnetic radiation from zero to infinity, starting from the shortest wavelengths and high frequencies to the longest wavelengths and lowest frequencies. It includes a wide range of light waves, but we can only see light within a certain range of wavelengths and frequency.
Visible light is near the center of the spectrum, with intermediate wavelengths and frequencies. The non-visible types of waves include radio waves, microwaves, infrared rays, ultraviolet rays, X-rays, etc.
Visible Light Communication = Illumination + Communication
Visible Light Communication (VLC) is a data communication variant which uses visible light between 400 and 800 THz. This means that any form of information can be sent using visible light. To be precise, VLC is a method of transmitting data using LEDs.
As the visible light spectrum is 1000 times larger than the radio frequency spectrum, VLC is regarded as a solution to RF bandwidth limitations.
The visible light source is capable of saving the extra power as it can be used for both illumination as well as communication. And this makes VLC a cheaper deal as compared to RF communication. Moreover, since light cannot trespass through physical environments (like walls), it’s a more secure way of communicating confidential data.
Use Cases of Light Communication
1. High-Speed Indoor Wireless Networks (LiFi)
LiFi is defined as a technology that uses the visible and infrared light spectrum to provide bi-directional (transmit and receive) capability. The LiFi framework involves multiple LED light bulbs that form a wireless communication network, offering a similar user experience to other wireless communication technologies such as Wi-Fi using the light spectrum. It comes with inherent wireless communication properties like multiple user access from single LiFi AP as well as complete mobility for users.
LiFi provides a high-speed, secure, dense and reliable wireless network for enterprise and home environments and acts as an enabler for smart buildings, intelligent transport, smart cities, and in the areas that are sensitive to electromagnetic radiation (such as aircrafts).
2. Wireless Backhaul Infrastructure for 5G/Telecom Operators
Unlike previous generations of mobile networks, the fifth generation (5G) technology is expected to fundamentally transform the role that telecommunications technology plays in the society. It is also expected to enable further economic growth and pervasive digitalisation of a hyper-connected society, where people are not only connected to the network whenever needed, but also to many other devices virtually creating an inter-connected society (i.e. Internet of Everything).
5G will, therefore, enable new use cases such as smart cities, smart agriculture, logistics and public safety agencies but simultaneously the spectral efficiency of 5G technology shall be much lower than the 3G or 4G/LTE. This will require densification of telecom infrastructure in terms of deployment of Macro cells and Small cells on every 150–200 meters i.e. lamp posts, building rooftops, public infrastructure, in-building cells etc.
Light communication based wireless backhaul solution for indoor & outdoor networks will be a future-proof and reliable backhauling solution not only for LTE and 5G but also for last mile connectivity in enterprise & FTTx broadband solutions.
3. Indoor Localisation for Retail Establishments/Airports
Light communication technology opens the door for retailers to engage and influence consumers on the retail floor more effectively.
LC enables way finding just like a GPS. It provides indoor location-positioning functionality that helps, for instance, shoppers in a mall to look for particular items, by guiding them in the right direction. The staff can also deliver targeted information to the customers regarding coupons or any other offers as they pass through a product section. All this can happen because light can communicate with smartphones with a camera.
Devices (such as sensors), can be incorporated within the LEDs to capture the traffic or activities at a store or huge offices. Similar mechanism creates huge value in all large establishments specifically airports where passengers can navigate to the desired location with ease. It also opens up augmented revenue generation opportunities for retailers & an accurate consumer/passenger behavior analytics for better product merchandising.
4. Vehicle to Vehicle Communication
LC can be used for communication in vehicles, thanks to the vehicle lights. They can detect a collision or any crashes, lane change warnings, emergency brakes, etc. We are moving in the era of highly secure & self-driving vehicles. LC can establish a complete wireless network on roads wherein each of the cars will be acting as a node.
5. Connectivity in Hospitals
In electromagnetic sensitive areas like hospitals, LC can play a vital role in preventing the interference of radio waves with other machines.
6. Underwater Communication
LC can be used in underwater communication using Un-Tethered Remotely Operated Vehicle (UTROV) for observatory maintenance of the oceans and ships’ deployment.
Thus, light communication is what we need, but it still has a long way to go. Have any queries? Comment below and let us know your feedback.