Li-Fi Technology
There are two main components to a light fidelity system. They are LED light bulb acting as an emitter, and photodetector acting as a receiver. The LED bulb is connected to the internet via Ethernet wires and transmits data through the light. On the receiving end, the photo detector is used to detect the light waves and send it through the amplification and processing unit. In this system, as soon the LED starts emitting light, the photo detector detects the light using binary codes. (Appendix A, Appendix B). The use of visual light makes it the fastest data transmission medium (Singh 2015).
A common misconception is that sunlight acts as interference to the li-fi signal, as shot noise which can’t be removed using optical filters. As fact, sunlight is highly useful as the solar cell enables the li-fi receivers acting as a data receiver device and sunlight can be used an energy source.
Many LED’s have the improved technology which can provide strong turn-on voltage which enables the li-fi operates with low amount of light for high data transfers. Therefore turning the LED ‘off’ to darken a room while retaining the li-fi signal is possible (Hass 2017).
Why Li-Fi?
A major limitation of Wi-Fi was the lack of security of the network and the data transmitted. Due its use of radio signals, its network can be hacked. In order to prevent data loss, companies had to encrypt the data with the help of software and other virtual security systems which eventually increase the cost (Batten et.al 2003).
Wi-Fi has a very limited application compared to li-fi. Limitations to speed (200mbps) and range (32 meters) are some of the factors which actually lead to development of li-fi in the year 2011. Li-fi has come a long way since then its application has reach to new possibilities and cost has significantly decreased.
Consumption of Wi-Fi data increased rapidly by 2010’s – 60% every year. Almost all data was consumed indoors using radio frequencies. Radio-frequency space slowly became overly saturated which resulted in a ‘spectrum crunch’ (Westmoreland 2017).
Therefore, Wi-Fi is now considered a superseded technology, as shown below:
| Li-Fi | Wi-Fi |
| Interference Issues | Does not have any issues regarding interference as it does not use radio frequencies | Will have issues regarding interference from WI-FI access points (routers) |
| Privacy in useage | The transmitting waves will be blocked by physical boundary and thus is more secure | The signals cannot be blocked by physical boundaries and thus could be accessed by third party from outside the physical premises |
| Speed | Up to 224 GBPS | From 150 MBPS to 1 GBPS |
| Operational Frequencies. | 10 thousand times frequency spectrum of the radio | 2.4 GHz, 4.9 GHz and 5 GHz |
| Density (DATA) | Can easily work in high dense environment. | Will only work in less dense environment due to interference-related issues |
(Sharma 2017) Cities like Sydney, Brisbane, and Melbourne already have over one million li-fi units in traffic and street lights, hospitals and other major premises. The cost of converting to li-fi transmission and LED’s has lowered considerably, particularly where existing Wi-Fi infrastructure already exists. However where it does not, the cost of expansion remains high.
Sydneysiders save $876 annually using LED li-fi enabled bulbs compared to older generation fluorescent bulbs (Geer 2017). The two billion dollars saved annually could be diverted to the cost of further regional and infrastructure expansion. (Appendix C).
Current Applications
Patient Monitoring System
Australia’s healthcare industry has become increasingly digitized (Australia Digital Health agency 2018). With the evolution of robotic surgery and substantial enhancement in this field, the role of network communication is paramount. In this fast-moving field, every activity needs to be done more effectively and with less physical presence by using new technologies.
Monitoring a patient’s health condition is achieved using li-fi monitoring via sensors attached to the patient’s body. The sensors convert data to binary codes for transmission (Sudha et.al 2016). With the help of a microcontroller, the transmission is converted into real data via a light-emitting diode. There are no wires and no harmful radioactive waves. The heart rate, pulse rate, blood pressure, temperature, respiratory condition, and glucose level are monitored carefully using sensors conveying information with li-fi (Shivakumar & Rajeswari 2016).
The Wireless Patient Monitor Sensor Platform (Appendix D) was similarly developed using the former Wi-Fi technology – now upgraded to li-fi. The system accurately conveys vital life sign information directly to the doctor, who can respond immediately (Deshmukh 2013).
This allows a more instantaneous response to irregularities in the patient, and reduces death rates significantly.
Vehicle to Vehicle Communications
Vehicles with inbuilt li-fi transponders act as both receivers and senders of information to sense collisions, apply safety measures when making their way through traffic, such as lane departure and automatic braking, and dynamic proximity cruise control for cars in front and rear. Inbuilt vehicle li-fi systems are aware of cars around them – actively acting as beacons for cars in front and behind – along with traffic lights and street lights acting as li-fi hubs. Vehicular Light Communication (VLC) uses light signals coming from both traffic signals and other cars to self-manage the flow of traffic in the event of traffic jams, accidents, hazards and to permit emergency vehicles unhindered road access. Cars utilize their GPS systems to assist with autonomous driving, knowing when to start, stop, apply turn signals, and make turns.
According to a study performed by NHTSA (2015) two decades ago, 90% of crashes occur due to human error. Across 2017 and 2018, Australia had an average of 1,220 road deaths in January according to the Australian Dept. Infrastructure, Regional Development and Cities (2018). Today, the road death toll has reduced to approximately 100 thanks to li-fi implementations. This is a 90% reduction in traffic incidents, as predicted by McKinsey & Company (2015) two decades ago (Appendix E, Appendix F).
That is not all. Traffic signals now enhanced with li-fi LED’s acting simultaneously as li-fi hubs, public emergency beacons, and news displays for weather reports. Tolls and fast-food drive throughs deduct payments from a user’s integrated vehicular li-fi system. Parking lots now house electric-vehicle charge points with li-fi transmitters, communicating free spaces and charging users wirelessly.
The future options for li-fi built into vehicles and traffic infrastructure provide amazing new potentials for all vehicles, including busses, rail and airplanes, to deliver safe and efficient new means to navigate and provide environmental awareness for passengers.
Retail
With the advancement of light fidelity has made some unique developments in the indoor positioning systems domain. The implementation of li-fi in retail industry has empowered retailers to enhance customer experience by bringing digital channels to physical stores, such as enabling location based interaction on mobile devices. Li-fi helps customers in navigation while taking advantage of location based alert and promotions. The implementation of li-fi in retail has been seamless due to the existing availability of LED lights in many stores. Li-fi in retail helps in all possible data transfer, all the way from the store-front to customer interaction and back-office coordination (Sarkar 2015). It also enables the store owners to synchronize it with their warehouse and automatically request inventory.
From a customer’s standpoint; the customers can be directed all the way from entering the store to the right position in the store for the products they are looking for, store owners can direct the customers to the store offers. From a store owner’s perspective, the owners can change the pricing and roll out discount prices across stores country wide from a centralized location. Li-fi provides the opportunities to roll out solutions, such as inventory checks or system upgrades, overnight.
The smart-trolley is also a game changer. The smart trolley interacts with customers during their shopping trip, marketing offers to the customer based on where they are in the supermarket. (Sharma 2017). Similarly, street lights with li-fi hubs broadcast advertisements conveying product information, offers, videos and catalogue information (Sharma 2017).
Li Fi Working Theory
Goals
- Accessibility – The government and industry related goals for li-fi would be to capitalize on the expanding technology to make it more widespread, and accessible to businesses but also to create the infrastructure for li-fi to upgrade into more remote regional areas.
- Innovation – New and innovative LED technologies also need to be sought to deliver light across greater ranges with longer-lifespans. Also new mediums of transmission.
Certainties
- High efficiency – Li-Fi has successfully been accepted as a high speed, highly secure and easy to adopt method of wireless internet transfer
- Beneficial to Industries – Li-Fi has brought positive changes to transport, medical and retail industries
- Economic Growth – Businesses are capitalizing on the many areas of growth for li-fi to expand on areas where it can be utilized.
- Continuing development – researchers continue to advance upon the existing technology, creating LED’s with stronger ranges, greater use of frequencies and longer lasting bulbs
Uncertainties
- Funding – Future costs of maintaining li-fi as part of government infrastructure across transport, medical and other means may require third party funding
- Natural Disasters – Natural disasters could affect existing infrastructure, requiring specialised service and maintenance
Limitations – Certain physical limitations of li-fi such as range and light interference may or may not improve or find adequate solutions - Hacking – As more advanced forms of hacking are found, it may only be a matter of time before the closed-wall nature of li-fi is exploited.
Drivers
- Existing Infrastructure – The existing government-supported infrastructure means that there is ample room to implement li-fi
- Bandwidth – Bandwidth limitations for wi-fi reaching upper limits require a new transmission modality
- Efficiency – Speed and cost-effectiveness means li-fi is an efficient solution for consumers
- Security – Li-fi is attractive to consumers for its closed-wall privacy
The goals for li-fi innovating upon existing li-fi technology, and achieving higher accessibility for those regional or undeveloped urban areas is justifiable based upon the drivers above. Certainties make the adoption of the li-fi technology easier, with benefits aiding cost effectiveness, providing economic growth and given the investment and development by business and industry presently. Unknown factors are generally uncontrollable, however the primary issue of funding may see further funds from third party investors rather than sought via government means.
Conclusions
Many start-up companies such as PureLifi, VLNComm and LightPointe have made great headway in developing the li-fi technology. Larger companies such as Qualcomm, GE, Panasonic, Philips, and Samsung are but a few who have further included li-fi in their current technology, including smartphones, televisions, tablets and laptops and smart-home devices. Li-fi, in near future will be a part of every smart building.
Farms of the future will be office farming with an eco-friendly approach. They will enable workers to have green space around them while growing farm produce monitored by LED based li-fi systems. The li-fi technology accommodates smart building features such as office farm monitoring as well as light and connectivity inside the building which reduces power consumption and increases the efficiency in the building.
The Military continue to develop li-fi, having produce underwater applications such as ROV’s and submarine to submarine communications. The Navy in the coming decades will be launching new fleet of submarines that will be fully equipped by li-fi.
With over 18 billion bulbs worldwide, initiatives have been taken to replace all the bulbs by smart LEDs making li-fi the communication future for humanity.
The advantages of li-fi are limitless and continuous development of this technology will help us drive future businesses. With the ever-growing population, Australia’s focus on energy efficiency, and flexibility of the li-fi spectrum, continual development of li-fi is the way of the future.
APPENDICES
Appendix A: Li-Fi Component Cost For An Office (Estimate)
| Cost of Li-Fi enabled LED bulb | $20 |
| Total number of LED bulbs in building (3000) | $60,000 |
| Cost of transmitting unit | $100 |
| Total number of transmitting units in building (3000) | $300,000 |
| Labour and installation | $140,000 |
| TOTAL COST OFFICE BUILDING AVERAGE | $500,000 |
Source: Suhail Ahmed Reshi – MBA (Marketing) Western Sydney University
