We live in an increasingly connected world today driven predominantly by the wireless revolution. WiFi has been the driving force which has shaped and transformed the internet connectivity landscape over the past two decades. However, with 50 billion devices predicted to be online by 2030, existing wireless networks are under tremendous strain to support this massive growth. We need a successor to cope with the upcoming data tsunami – this is where LiFi seems to be a promising solution.
In this extensive guide, we take a closer look at various aspects of this new technology – how it works, comparison with WiFi, commercial status, futuristic applications and also bust some common myths. Read on to get your queries answered in simple terms on Light Fidelity (LiFi)!
What Exactly is LiFi?
The concept of LiFi was first introduced by Professor Harald Haas from University of Edinburgh, UK back in his 2011 TED Talk. He demonstrated the possibility of sending information encoded in LED light pulses at very high speeds. Essentially, LiFi allows wireless communication between electronic devices through visible light communication (VLC) using standard LED bulbs rather than traditional radio frequencies as in WiFi.
Haas also founded pureLiFi in 2012 – one of the pioneering companies alongside large firms like Signify, LVX System and Fraunhofer HHI which are driving this technology today towards commercial deployments.
Key Benefits of LiFi over WiFi:
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Faster data rates exceeding 100 Gbps theoretically
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More capacity with wider spectrum availability
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Enhanced security as signals confined to a room
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Elimination of electromagnetic interference
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Much better availability through LED light sources
So in a nutshell, LiFi aims to eventually complement WiFi by addressing some key gaps using the immense optical spectrum for data transmission through LEDs which act as access points. Let‘s take a closer look at how this fascinating wireless communication works!
Principle Behind High Speed Bi-directional LiFi Communication
The basic principle leveraged in LiFi systems is intensity modulation and direct detection (IM/DD). A bright visible LED light which is normally used for illumination is used as the data transmitter. This LED light intensity is varied at extremely high speeds imperceptible to the human eye by modulating the driving circuitry ON and OFF to generate digital bits.
Discrete optical power levels indicate logical 0 or logical 1 to mimic a binary signal. For a simple example, let the LED ON state represent a 1 bit and OFF state represent a 0 bit. By switching the LED at megabit speeds, a digital data stream can thus be encoded into the light.
At the receiver side, a fast photodiode detects this subtle high speed intensity fluctuation and generates corresponding electric current pulses. This photocurrent is then decoded to extract the transmitted binary data. Through this mechanism, the intensity modulation essentially helps embed high speed data readily within the instantaneous power emitted by standard LED bulbs which can be recovered using LiFi terminals.
This technique easily enables data rates exceeding gigabits per second with good signal-to-noise ratio. Thanks to advanced modulation schemes like OFDM, data rates as high as 10 Gbps have already been demonstrated over distance of 10 meters through the visible light spectrum in lab environments.
For bi-direction communications required in networks, both source and destination need an LED transmitter module and a photodiode receiver module. With rapid strides in solid state lighting combined with imaging and optic communication technologies, LiFi aims to leverage the LED and photodiode ubiquity to deliver seamless high speed wireless internet connectivity.
LiFi Set to Join Mainstream – The New IEEE 802.11bb Standard
The Institute of Electrical and Electronics Engineers (IEEE) which oversees technical standards for WiFi networks has finally embraced the advancement in visible light communication through a dedicated standard for LiFi named 802.11bb. This was necessitated by the fact that a tremendous amount of research and prototyping over the past decade had proven LiFi‘s capabilities and readiness for real-world usage.
The latest 802.11 release has two modes of operation defined for LiFi:
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LiFi Access Point (AP) mode similar to a WiFi hotspot
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LiFi Peer-to-Peer (P2P) mode for device-to-device networking
The standard specifies mechanisms for coexistence between LiFi and WiFi data links for interoperability. By bringing LiFi under the wider IEEE 802.11 umbrella covering WiFi standards, this integration will accelerate adoption among device makers and communication networks to easily offer LiFi connectivity alongside WiFi.
Does LiFi Score Over WiFi? Comparative Analysis
The advent of LiFi has sparked interesting debates whether it can beat WiFi or not. Let‘s analyze across some key parameters to conclude:
Speed and Latency
| Metric | LiFi | WiFi |
|---|---|---|
| Max Speed | >100 Gbps demonstrated | Typical is up to 1 Gbps |
| Latency | < 10 microseconds | > 10 microseconds |
Owing to the wide frequency range within visual light spectrum available, LiFi can support exceedingly high data rates compared to WiFi. Lower latency is an added advantage.
Range and Mobility
| Metric | LiFi | WiFi |
|---|---|---|
| Range | Up to 10 meters radius | 100 meters outdoors |
| Mobility Support | Low | High |
Coverage range and user mobility support are clear wins for WiFi over LiFi links which span shorter distances from transmitter to receiver. Enhanced mobility is still an active research domain for LiFi.
Interference Performance
LiFi outscores WiFi hands down when it comes to resilience against electromagnetic interference. WiFi signals often degrade in presence of other interfering radio signals and physical barriers.
Use Cases
LiFi is ideally suited for deployment across medical, aviation, automotive, underwater and other areas with needs for security, high capacity and resistance to interference. WiFi prevails for conventional internet access.
Security
By confinement of light within limited spaces, interception or sniffing of data is not easy providing inherent security strength for LiFi. WiFi signals can be intruded beyond walls easily.
Overall, while WiFi is the popular wireless standard now with strong mobility support, LiFi brings complementary benefits like high speed, low latency, security and capacity which would make it preferred choice in specific usage scenarios.
Demystifying Common Myths Around LiFi
As an emerging niche technology still in adoption phase, some opacity exists on how LiFi functions. Let‘s clarify certain popular myths:
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LiFi uses dangerous or harmful light: LiFi relies on visible light which has longer wavelengths than ultra-violet rays and is completely safe for people.
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LiFi requires the light source to be always switched ON: While the optical transmitter LED needs to be powered ON to send data, the light intensity can be dimmed to low levels comfortable for humans when there is no active transmission.
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Bad weather deteriorates LiFi links: Rain or fog may absorb certain incident light frequency components but does not interfere with modulation used in LiFi. Links work unaffected.
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Any household bulb can enable LiFi: Actually, LED lamps require retrofits to drive the rapid ON-OFF modulation used in LiFi. But any standard streetlight style LED bulb can be upgraded to deliver Gbps internet!
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Line of sight is compulsory: Reflected light transmission also gives decent throughput rate of more than 50 Mbps allowing some obstruction between source and destination.
On the whole, LiFi aims to provide reliable high speed wireless communication without health side-effects leveraging LED lighting fixtures widespread today.
Mapping the LiFi Industry Ecosystem and Supply Chain
An entire industrial ecosystem spanning components, equipment providers, chip makers, software and system integrators is evolving to unlock the promise of this new optical wireless standard globally. Here is a partial list of key players:
- pureLiFi, Oledcomm – LiFi Access Points
- Signify, LG, Oledcomm – Integrated Luminaires
- Semiconductor Companies – PDs, LED drivers – Hamamatsu Photonics, Panasonic
- Networking Gear Makers – Huawei, Cisco, Nokia
- Software Specialists – Golem, Lightbee, Velmenni
Besides the above players driving R&D and product development tailored for LiFi ecosystems, this new wireless technology has attracted interest from leading technology giants including Apple, Facebook and Google which have acquired specialist startups indicating significant future market opportunities.
With falling hardware costs and standardization, affordable LiFi enabled consumer electronics products integrated into lighting equipment for indoor settings might soon be within reach!
Where Does LiFi Adoption Stand Today and What is Holding it Back?
First and foremost, lack of awareness among general populace exists as LiFi remains still an industry terminology. At present, active deployments are largely limited to certain commercial use cases like in-flight internet connectivity and hospitals where extremely reliable and low-latency links are paramount.
For example, Air France and Emirates already have optically connected cabin systems technology from pureLiFi and Latécoère. In hospitals, LiFi helps clinicians securely access patient records on the fly without causing interference. Companies like Oledcomm, VLNComm, Signify are driving pilots across medical, retail, defense sectors.
Challenges to Address for Mainstream Adoption:
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Requirement of direct line of sight between transmitter and receiver
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Low mobility support during active data transfers
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Range limitation which reduces flexibility for device movements
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High installation costs compared to WiFi equipment
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Lack of compatibility with existing WiFi network router devices
However, the LiFi industry is expected to be worth USD 85 billion by 2027. With rising maturity of suitable modulation and multiplexing techniques combined with knowhow from visible light communication and photonics applications getting transferred to the newer LiFi platforms, rapid strides towards unlocking full potential for this spectrum are being made.
Exploring Futuristic Killer Applications of LiFi – Beyond Mobile Internet
LiFi undoubtedly holds great promise in specific areas where limitations of WiFi prove bottleneck:
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Robotics and Industrial Automation: Eliminating interference while enabling machine to machine communication with low latency
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Smart Transportation: Low latency alerts combined with enhanced security necessary for driverless vehicles
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Underwater Connectivity: Optical wireless technology allowing internet and sensing across water medium
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Hazardous Environments: Signaling in petroleum, chemical or power plants safely
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IoT and Smart Cities: LiFi-enabled smart street lighting doubling up as urban data network
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Wearables and Implants: High speed body-centric networks like smart contact lenses
Further into the future, LiFi is sure to pave the way for radical applications still inconceivable today, just like the disruption sparked off decades ago by the advent of WiFi itself!
Resources to Try Out LiFi Hands-on
For engineers, researchers or students keen on gaining practical knowhow on LiFi systems, there exist certain helpful learning material:
Starter Kit and Development Board
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SP5000E Dev Kit from pureLiFi for prototyping Gbps links
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Open source Arduino shield for custom experiments
Books
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Getting Started with LiFi by Jon Arne Grytnes – Step by step tutorials
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LiFi Enabled by Jyoti Rathore – Demystifying theoretical concepts
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Build Your Own LiFi Network by A. Muriith – DIY projects covered
Hands-on Course Bundle from Udemy
- Lab exercises on modulation, link planning and troubleshooting
YouTube Channels
- LiFi University – Video demos and training webcasts
With these excellent references, any learner can gain invaluable practical knowledge on various concepts underlying this forward-looking optical wireless technology and its implementation.
Conclusion – Let There Not Be Darkness When it Comes to Wireless Connectivity!
Will LiFi replace WiFi completely? Most probably not, as both technologies have certain complementary strengths catering to specific networking requirements which will co-exist together powering the world’s communication needs. WiFi will continue to dominate widespread internet access over the next 5-10 years given its cost advantage and extensive penetration.
However, with stability, security and high throughput necessities across industries served by autonomous systems, IoT, robotics and mobility solutions which existing RF networks struggle to fully address today, LiFi adoption will gradually gain critical mass this decade. Thanks to dedicated integration efforts as part of the new IEEE standard coupled with rapid evolution of high speed optical and lighting devices through solid state lighting innovations, affordable LiFi at scale is not an impossibility at all.
The dream of future cities illuminated with multifunctional intelligent lighting which provides ultra-responsive and omnipresent wireless connectivity could be realized through LiFi advancements, ushering an era of ‘Internet of Lights’!
So are you ready to welcome the power of light to transform the way we communicate wirelessly? Do share this intro guide with folks who might still be perplexed about how exactly LiFi technology works to dispel myths and trigger valuable discussions. Should you have any other queries on LiFi, post them in comments below.
