LiFi – The New Internet

LiFi The New Internet

In this LiFi blog we will learn  the Following

• What LiFi is
• How LiFi is already a 5G- technology
• How LiFi vs WiFi in a speed and capabilities comparison
• We will take a look at a LiFi project were complete LiFi cellular networks have been created
• LiFi Technology uses across a number of existing fields and emerging industries
• LiFi products and applications for todays use and future use

LiFi

LiFi uses the visible light spectrum and infrared for wireless high speed data communication. LiFi used the theory of visible light communication (VLC) to successfully reach a high speed , bi-directional wireless network that provides secure multiuser access with complete mobility.  The LiFi light spectrum is over 2600 X’s the radio prevalence / frequency spectrum …

The radio frequency (RF) spectrum is only a fraction of the entire electromagnetic spectrum. LiFi’s visible light spectrum and the infrared (IR) spectrum are unregulated, and offer 780 THz of bandwidth.

LiFi is the only viable solution to the WiFi / Radio frequency spectrum crunch . Wireless traffic has grown on average 60% over the last 10 years . With this average growth projection over the next 20 years the  WiFi / Radio frequency spectrum would have to be 12,000 X’s its current size in order to sustain usage efficiency. The entire WiFi / Radio frequency spectrum is only 0.3 THz. To  meet the projected requirements that will be put on the WiFi / Radio frequency spectrum over the next 20 years it would have to be 6 THz . The LiFi spectrum is 75,000 THz which means LiFi is not only the key to the inevitable  WiFi / Radio frequency spectrum crunch dilemma . LiFi is the assured solution for quite some time …

Wi-Fi companies have used the small cell concept for the geographical reuse of frequencies to try and overcome the looming spectrum crunch. The cell radius of the cellular communications have reduced as follows 2G/35km ,3G/5km, 4G /100m , 5G/ 25m.  The use of LiFi will be an eventual need as the scaling down of cell sizes a higher infrastructure cost for the backhaul and  fronthaul datalinks which connect the small cell access points to the networks core. The smaller cell size the line of site between base station and user terminal will significantly reduce date rate and cause cellular network problems. Wi-Fi access points have been secured under the seats in stadia to use the human body as an attenuator for RF signals to avoid the line of sight obtrusions making it a non viable solution for home and office usage. Making LiFi a vary attractive solution due to LiFi being plentiful and LiFi being license-free.

LiFi uses the resources shown for data communication which has been successfully used for decades in fiber -optic communications of light amplification . Now with the adoption of LEDs in high use we can use LiFi for wireless networking .

At the beginning LiFi systems were used as a single point – to -point wireless link a LED source and a receiver with a photo detector.  Lifi’s achievable data is dependent on digital modulation and lighting technology …

The chart above shows LiFi achievable data speeds are based on the light sources. red, green and blue (RGB) LEDs; Gallium Nitride (GaN) micro LEDs and laser-based lighting.

To perfect LiFi there had to be a variety of experiments below is the problem and solutions found.

• Problem – Most standard commercial buildings, homes and exterior lighting fixtures have a color temperature between 2700K and 5000K, these LEDs have a blue high brightness with the phosphorous coating converting the blue light into yellow. Combining the blue and yellow light together is seen as the most cost effective way to produce white light but the phosphorous color converting narrows the LiFi frequency response. The LiFi bandwidth for this type of LED is in the range of 2MHz .
• Solution A – LiFi products now have added a blue filter at the receiver to remove the slow yellow component making it possable for LiFi to achieve data rates of 1Gbps .
• Solution B – Red , Green , and Blue (RGB) LEDs give LiFi the ability to reach data rates of 5Gbps making white light by mixing the base colors opposed to a chemical conversion.
• Solution C – LiFi has been recorded at 8Gbps with the use of a single micro LED , and it is now shown that LiFi can reach 100Gbps with laser based lighting

The 4 major advantages of LiFi in wireless networking

• LiFi magnitude of enhanced data densities
• LiFi properties to enhance physical layer security
• LiFi ability to be used in places were RF is banned i.e. neonatal wards and all hospital rooms , petrochemical plants and oil plat forms
• LiFi ability to work using (PoE) which provides the opportunity connect to existing networks for the required backhaul connections between the light sources with its integrated LiFi modem and Internet

The image above shows a LiFi attocell network. The room shows several light fixtures driven by a LiFi modem or a LiFi chip which serves as a data access point while providing room illumination. The LiFi Lighting units are connected to the network by high speed backhaul connections. The fixtures turn off and on at a extremely high frequency which can not be picked up by the human eye which allows the fixtures to communicate in binary code. LiFi products can be can have power and data connected via PoE or by using a Ethernet cable and hard wiring the fixture directly into the existing  power supply . To use most LiFi products you simply plug in the USB into your computer or lap top down load the software . Plug the LiFi dongle into the port on your computer . and begin using . There are a variety of LiFi Apps that give you the ability to use LiFi on your cell phone and computer . The LiFi Lighting Fixtures are very easy to install as well , choose a location were the light from the fixture will shine on the most computers or internet enabled devices possable , Install the LiFi fixture the same as you would install any other fixture and plug in the PoE cable into the designated port or  hard wire in the LiFi fixture and plug in the ethernet cable in its designated port . LiFi works similar to the way cell towers work as you move out of  the range of one LiFi zone the next LiFi zone will provide coverage.  Then if you are to walk out of the LiFi coverage area all together your standard WiFi  will pick right up on your device…

LiFi vs Wi-Fi

• LiFi speed –  In an office setting with a standard WiFi system of a 100Mbps if there is an office of 15 people the speed goes down to 4 to 6 Mbps due to the band width being shared with a LiFi system single fixture that runs at 42Mbps can give every one with in that LiFi zone the 42Mbps speed at the same time no matter how big the file they are down loading  due to a band width 1000 larger.
• LiFi ROI – Studies have been shown to prove  that every year a company looses over 1 week of an employees productivity due to slow internet. With  LiFi  there is no down time  time due to slow internet speeds.
• LiFi Versatility – LiFi works in areas were RF is not allowed due to safety concerns i.e. Neonatal , and hospital rooms were delicately calibrated hospital machinery is located , Petrochemical plants and areas were explosives are held. LiFi can work deep underwater and other areas were security is of major concern as it will not transfer data through walls . LiFi can be set up in the most remote locations on earth ( LiFi has been in use in Africa for a number of years now providing internet services to African villages that Wi Fi  can not reach ) . LiFi can be used in diffrent light spectrums to work in the day light such as infrared . With The Wi-Fi spectrum crunch right around the corner its only a matter of time until LiFi becomes the new internet .
• LiFi Products – LiFi can be installed in a large variety of lighting fixtures and solar panels , Companies like LiFi Lighting are working with a variety of LiFi manufacturers across the world to make the LiFi market pricing competitive as of right now the average price LiFi product price point is between 1400 to 5000 USD . With price projected to decrease in 2019 due to newer models being designed with higher Mpbs speeds.

LiFi Technology

LiFi is a technology that is set to impact many industries. LiFi is an established 5G technology. It is unlocking the IoT, drive Industry 4.0 applications, light-as-a-service (LaaS) , enabling new intelligent transport system methods , LiFi will enhance road safety by its use in driverless cars and advance warning systems in newer vehicles, create new cybersecure networks, enable new systems of health monitoring for the disabled and aging populations,  LiFi will offer new solutions to close digital divides, and enable a Gigabit-speed wireless connections in future datacenters. LiFi will merger of two the major industries of wireless communications and lighting. In near future LiFi will serve thousands of applications such as smart cities, smart homes and the IoT.

Light as a service (LaaS) will be a dominating LiFi theme in the lighting industry, and will be a driving force requiring new business models. LaaS in combination with LiFi will allow the lighting industry to enter the wireless communications market. LiFi will have the potential to create a paradigm shift in the wireless industry by moving from cm-wave communication to nm-wave communication making the wireless industry and lighting industry merge into one market. LiFi prerequisite for the large-scale adoption is the available in the following standards. IEEE 802.15.7, IEEE 802.11 as well as ITU-R to standardize LiFi technology.

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