LI-FI LIGHTCASTING

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TELECOM: LIGHT-CASTING EVEN WORKS IN OUTER SPACE

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Inquire about acquiring the issued mobile device patents on this technology

SCOTT'S PATENTED LIGHT-CASTING(TM) EVEN WORKS IN OUTER SPACE

THE INTERNET: POWERED BY LIGHT!

In 1977, a group of technicians and engineers in San Francisco, California went up on top of a mountain in the middle of San Francisco, named Twin Peaks, and broadcast the internet across all of San Francisco, Oakland and Berkeley in Northern California. They did not use wires or radio waves. They used light.

Entrepreneur and technologist Scott Douglas Redmond ( http://www.scottdouglasredmond.com/ ) , and his team of brilliant engineers rigged up a system on the mountain designed to save time and money, but they soon discovered other advantages. The city of San Francisco gave him the mountain for nearly a week, during which he received a mayoral proclamation and the donation of an entire radio station and the main laser used in Star Wars for special effects.

What happens when you give a legion of engineers a whole mountain in the middle of San Francisco?

…They beam light, audio and video to over two million people….just for fun!

Take 148 crew, one mountain, a city center with 7 million people around it and more candle-power than many small cities have, and you get the first outdoor urban light networked experience for a whole city!

The event was viewed by millions but 1000 people interacted with it on the first public web, connected by light

 

You could see the event, hear the event on the radio, transduce audio from the light and transduce basic video from the light. It was one of the first mass broadcasts using light as the delivery platform. If you were close enough, you could feel the sound. Satellites could see the event. Mr. Redmond has now taken this technology to consumer pockets. He has built mini versions of his Lightcaster and has been issued multiple patents by the U.S. Government on cell phones networked by light. Redmond has offered the patents, engineering and manufacturing rights to any manufacturer who wishes to deliver the “lightphone” to the volume consumer market.

WAVEY GRAVY – THE MC IN THE FILM: “WOODSTOCK”, Keeping the crew fired up at one of the Twin Peaks lightcasting events


 

This kind of internet-by-light now has a name. It is often called Light-Fi or Li-Fi

Li-Fi (Light Fidelity) is a bidirectional, high speed and fully networked wireless communication technology similar to Wi-Fi. The term was coined by Harald Haas [1] and is a form of visible light communication and a subset of optical wireless communications (OWC) and could be a complement to RF communication (Wi-Fi or Cellular network), or even a replacement in contexts of data broadcasting. It is so far measured to be about 100 times faster than some Wi-Fi implementations, reaching speeds of 224 gigabits per second.[2]

It is wireless and uses visible light communication or infra-red and near ultraviolet (instead of radio frequency waves) spectrum, part of optical wireless communications technology, which carries much more information, and has been proposed as a solution to the RF-bandwidth limitations.[3]

Technology details

This OWC technology uses light from light-emitting diodes (LEDs) as a medium to deliver networked, mobile, high-speed communication in a similar manner to Wi-Fi.[4] The Li-Fi market is projected to have a compound annual growth rate of 82% from 2013 to 2018 and to be worth over $6 billion per year by 2018.[5]

Visible light communications (VLC) works by switching the current to the LEDs off and on at a very high rate,[6] too quick to be noticed by the human eye. Although Li-Fi LEDs would have to be kept on to transmit data, they could be dimmed to below human visibility while still emitting enough light to carry data.[7] The light waves cannot penetrate walls which makes a much shorter range, though more secure from hacking, relative to Wi-Fi.[8][9] Direct line of sight isn't necessary for Li-Fi to transmit a signal; light reflected off the walls can achieve 70 Mbit/s.[10][11]

Li-Fi has the advantage of being useful in electromagnetic sensitive areas such as in aircraft cabins, hospitals and nuclear power plants[citation needed] without causing electromagnetic interference.[8][9] Both Wi-Fi and Li-Fi transmit data over the electromagnetic spectrum, but whereas Wi-Fi utilizes radio waves, Li-Fi uses visible light. While the US Federal Communications Commission has warned of a potential spectrum crisis because Wi-Fi is close to full capacity, Li-Fi has almost no limitations on capacity.[12] The visible light spectrum is 10,000 times larger than the entire radio frequency spectrum.[13] Researchers have reached data rates of over 10 Gbit/s, which is much faster than typical fast broadband in 2013.[14][15] Li-Fi is expected to be ten times cheaper than Wi-Fi.[7] Short range, low reliability and high installation costs are the potential downsides.[5][6]

PureLiFi demonstrated the first commercially available Li-Fi system, the Li-1st, at the 2014 Mobile World Congress in Barcelona.[16]

Bg-Fi is a Li-Fi system consisting of an application for a mobile device, and a simple consumer product, like an IoT (Internet of Things) device, with color sensor, microcontroller, and embedded software. Light from the mobile device display communicates to the color sensor on the consumer product, which converts the light into digital information. Light emitting diodes enable the consumer product to communicate synchronously with the mobile device.[17][18]

History

Harald Haas, who teaches at the University of Edinburgh in the UK, coined the term "Li-Fi" at his TED Global Talk where he introduced the idea of "Wireless data from every light".[19] He is Chair of Mobile Communications at the University of Edinburgh and co-founder of pureLiFi.[20]

The general term visible light communication (VLC), whose history dates back to the 1880s, includes any use of the visible light portion of the electromagnetic spectrum to transmit information. The D-Light project at Edinburgh's Institute for Digital Communications was funded from January 2010 to January 2012.[21] Haas promoted this technology in his 2011 TED Global talk and helped start a company to market it.[22] PureLiFi, formerly pureVLC, is an original equipment manufacturer (OEM) firm set up to commercialize Li-Fi products for integration with existing LED-lighting systems.[23][24]

In October 2011, companies and industry groups formed the Li-Fi Consortium, to promote high-speed optical wireless systems and to overcome the limited amount of radio-based wireless spectrum available by exploiting a completely different part of the electromagnetic spectrum.[25]

A number of companies offer uni-directional VLC products, which is not the same as Li-Fi - a term defined by the IEEE 802.15.7r1 standardization committee.[26]

VLC technology was exhibited in 2012 using Li-Fi.[27] By August 2013, data rates of over 1.6 Gbit/s were demonstrated over a single color LED.[28] In September 2013, a press release said that Li-Fi, or VLC systems in general, do not require line-of-sight conditions.[29] In October 2013, it was reported Chinese manufacturers were working on Li-Fi development kits.[30]

In April 2014, the Russian company Stins Coman announced the development of a Li-Fi wireless local network called BeamCaster. Their current module transfers data at 1.25 gigabytes per second but they foresee boosting speeds up to 5 GB/second in the near future.[31] In 2014 a new record was established by Sisoft (a Mexican company) that was able to transfer data at speeds of up to 10Gbit/s across a light spectrum emitted by LED lamps.[32]

Standards

Like Wi-Fi, Li-Fi is wireless and uses similar 802.11 protocols; but it uses visible light communication (instead of radio frequency waves), which has much wider bandwidth.

One part of VLC is modeled after communication protocols established by the IEEE 802 workgroup. However, the IEEE 802.15.7 standard is out-of-date, it fails to consider the latest technological developments in the field of optical wireless communications, specifically with the introduction of optical orthogonal frequency-division multiplexing (O-OFDM) modulation methods which have been optimized for data rates, multiple-access and energy efficiency.[33] The introduction of O-OFDM means that a new drive for standardization of optical wireless communications is required.

Nonetheless, the IEEE 802.15.7 standard defines the physical layer (PHY) and media access control (MAC) layer. The standard is able to deliver enough data rates to transmit audio, video and multimedia services. It takes into account optical transmission mobility, its compatibility with artificial lighting present in infrastructures, and the interference which may be generated by ambient lighting. The MAC layer permits using the link with the other layers as with the TCP/IP protocol.[citation needed]

The standard defines three PHY layers with different rates:

  • The PHY I was established for outdoor application and works from 11.67 kbit/s to 267.6 kbit/s.

  • The PHY II layer permits reaching data rates from 1.25 Mbit/s to 96 Mbit/s.

  • The PHY III is used for many emissions sources with a particular modulation method called color shift keying (CSK). PHY III can deliver rates from 12 Mbit/s to 96 Mbit/s.[34]

The modulation formats recognized for PHY I and PHY II are on-off keying (OOK) and variable pulse position modulation (VPPM). The Manchester coding used for the PHY I and PHY II layers includes the clock inside the transmitted data by representing a logic 0 with an OOK symbol "01" and a logic 1 with an OOK symbol "10", all with a DC component. The DC component avoids light extinction in case of an extended run of logic 0's.[citation needed]

The first VLC smartphone prototype was presented at the Consumer Electronics Show in Las Vegas from January 7–10 in 2014. The phone uses SunPartner's Wysips CONNECT, a technique that converts light waves into usable energy, making the phone capable of receiving and decoding signals without drawing on its battery.[35][36] A clear thin layer of crystal glass can be added to small screens like watches and smartphones that make them solar powered. Smartphones could gain 15% more battery life during a typical day. This first smartphones using this technology should arrive in 2015. This screen can also receive VLC signals as well as the smartphone camera.[37] The cost of these screens per smartphone is between $2 and $3, much cheaper than most new technology.[38]

Philips lighting company has developed a VLC system for shoppers at stores. They have to download an app on their smartphone and then their smartphone works with the LEDs in the store. The LEDs can pinpoint where they are located in the store and give them corresponding coupons and information based on which aisle they are on and what they are looking at.[39]

Internet by light promises to leave Wi-Fi eating dust

By Laure Fillon


 

Barcelona (AFP) - Connecting your smartphone to the web with just a lamp -- that is the promise of Li-Fi, featuring Internet access 100 times faster than Wi-Fi with revolutionary wireless technology.

French start-up Oledcomm demonstrated the technology at the Mobile World Congress, the world's biggest mobile fair, in Barcelona. As soon as a smartphone was placed under an office lamp, it started playing a video.

The big advantage of Li-Fi, short for "light fidelity", is its lightning speed.

Laboratory tests have shown theoretical speeds of over 200 Gbps -- fast enough to "download the equivalent of 23 DVDs in one second", the founder and head of Oledcomm, Suat Topsu, told AFP.

"Li-Fi allows speeds that are 100 times faster than Wi-Fi" which uses radio waves to transmit data, he added.

The technology uses the frequencies generated by LED bulbs -- which flicker on and off imperceptibly thousands of times a second -- to beam information through the air, leading it to be dubbed the "digital equivalent of Morse Code".

View gallery

A delegate checks his smartphone at the Mobile World Congress in Barcelona, on February 22, 2016 (AF …

It started making its way out of laboratories in 2015 to be tested in everyday settings in France, a Li-Fi pioneer, such as a museums and shopping malls. It has also seen test runs in Belgium, Estonia and India.

Dutch medical equipment and lighting group Philips is reportedly interested in the technology and Apple may integrate it in its next smartphone, the iPhone7, due out at the end of the year, according to tech media.

With analysts predicting the number of objects that are connected to the Internet soaring to 50 million by 2020 and the spectrum for radio waves used by Wi-Fi in short supply, Li-Fi offers a viable alternative, according to its promoters.

"We are going to connect our coffee machine, our washing machine, our tooth brush. But you can't have more than ten objects connected in Bluetooth or Wi-Fi without interference," said Topsu.

Deepak Solanki, the founder and chief executive of Estonian firm Velmenni which tested Li-fi in an industrial space last year, told AFP he expected that "two years down the line the technology can be commercialised and people can see its use at different levels."

 

Li-Fi has been tested in France, Belgium, Estonia and India (AFP Photo/Sam Yeh)

- 'Still laboratory technology' -

Analysts said it was still hard to say if Li-Fi will become the new Wi-Fi.

"It is still a laboratory technology," said Frederic Sarrat, an analyst and consultancy firm PwC.

Much will depend on how Wi-Fi evolves in the coming years, said Gartner chief analyst Jim Tully.

"Wi-Fi has shown a capability to continuously increase its communication speed with each successive generation of the technology," he told AFP.

Li-Fi (Light-Fidelity) has reached speeds of over 200 Gbps (AFP Photo/Jung Yeon-Je)

Li-fi has its drawbacks -- it only works if a smartphone or other device is placed directly in the light and it cannot travel through walls.

This restricts its use to smaller spaces, but Tully said this could limit the risk of data theft.

"Unlike Wi-Fi, Li-Fi can potentially be directed and beamed at a particular user in order to enhance the privacy of transmissions," he said.

Backers of Li-Fi say it would also be ideal in places where Wi-Fi is restricted to some areas such as schools and hospitals.

"Li-fi has a place in hospitals because it does not create interference with medical materials," said Joel Denimal, head of French lighting manufacturer Coolight.

In supermarkets it could be used to give information about a product, or in museums about a painting, by using lamps placed nearby.

It could also be useful on aircraft, in underground garages and any place where lack of Internet


 


 

Read More about internet-by-light:

  • Tsonev, Dobroslav; Videv, Stefan; Haas, Harald (December 18, 2013). "Light fidelity (Li-Fi): towards all-optical networking". Proc. SPIE (Broadband Access Communication Technologies VIII) 9007 (2). doi:10.1117/12.2044649.

  • "pureVLC Ltd". Enterprise showcase. University of Edinburgh. Retrieved 22 October 2013.

  • Tsonev, D.; Sinanovic, S.; Haas, Harald (15 September 2013). "Complete Modeling of Nonlinear Distortion in OFDM-Based Optical Wireless Communication". IEEE Journal of Lightwave Technology 31 (18): 3064–3076. doi:10.1109/JLT.2013.2278675.

  1. Philips Creates Shopping Assistant with LEDs and Smart Phone, IEEE Spectrum, 18 February 2014, Martin LaMonica


 

 

READ THIS TECH DOC ON LIGHTCASTING: LiFi News.pdf

The information transfer from a laser satellite will be 90 to 100 times faster than the speed of a home Internet connection, and hours faster than from current satellites.

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By Lonnie Shekhtman, Staff  

The European Space Agency Saturday launched a telecommunications satellite into space from Baikonur, Kazakhstan, that will use lasers to gather information from Earth observation satellites and quickly send it to sensors on Earth. The launch was part of a project known as European Data Relay System, or EDRS, and is the first of several of these data-transfer satellites that will be launched into space in the next several years. The ESA says that its new laser communications network will create what it calls a “SpaceDataHighway,” able to transfer information such as photos and videos from Earth observation satellites, drones, and even from the International Space Station down to Earth at a near real-time speed of 1.8 Gigabits per second. This is 90 to 100 times faster than the speed of a home Internet connection, says the ESA. Recommended: How well do you know the moon? Take our quiz! “EDRS is one of a kind and ESA’s most ambitious telecom programme to date, creating the means for an entirely new market in commercial satellite communications,” the agency said in an announcement. The faster transmission speed will be a boost to responders to disasters, pollution incidents, or illegal fishing or ocean piracy, for example, who could make better decisions with more immediate access to satellite data. "Some important shipping routes go through the North Pole region, where thick-ice [floes] can cause damage to vessels and even threaten human life," Magali Vaissiere, ESA's director of telecommunications told the BBC. "It's also an environment in constant motion which means that data that is two days old is not only unhelpful – it could even be unsafe,” she said, referring to the limitations of traditional radio satellites. Current satellites in low Earth orbit are able only to send back the data they collect during their 100-minute orbit time around Earth during a 10-minute window when they have line-of-sight with sensors on Earth. ESA’s first optical satellite will remain in a stationary position higher in space (same as television satellites) than other satellites, about 36,000 kilometers (nearly 23,000 miles) from the Earth's equator and above Europe. It will collect data from this location and relay it down to European ground stations, avoiding the time delay when other Earth observation satellites have to wait for “line of sight” with ground stations, says the ESA. EDRS laser technology was developed by German satellite builder Tesat, a subsidiary of French aerospace company Airbus at a cost of 500 million euros. The laser terminal will be tested over the coming weeks and months with ground stations in Germany, Belgium, and the United Kingdom, and is expected to be fully operational this summer, when it should start serving its first customer, the European Commission. Over the next several years, ESA plans to discharge two more laser-equipped satellites into space, one over Europe and the other over the Asia-Pacific region. Their biggest challenge, said ESA project manager Michael Witting, will be to get these laser terminals to talk to each other. "It's a laser beam; you have to point it accurately. It's the same as taking a torch in Europe and pointing at a two-euro coin in New York,” Mr. Witting told ArsTechnica. “That's one of the main challenges for developing the laser communication terminal, but also developing the satellite – it has to be stable enough to allow that kind of accuracy," he said. The rise of Wi-Fi and cellular data services made Internet access more convenient and ubiquitous. Now some of the high-speed backhaul data that powers Internet services looks set to go wireless, too.

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  Technology that uses parallel radio and laser links to move data through the air at high speeds, in wireless hops of up to 10 kilometers at a time, is in trials with three of the largest U.S. Internet carriers. It is also being rolled out by one telecommunications provider in Mexico, and is helping build out the Internet infrastructure of Nigeria, a country that was connected to a new high-capacity submarine cable from Europe last year. AOptix, the company behind the technology, pitches it as a cheaper and more practical alternative to laying new fiber optic cables. Efforts to dig trenches to install fiber in urban areas face significant bureaucratic and physical challenges. Meanwhile, many rural areas and developing countries lack the infrastructure needed to support fiber, says Chandra Pusarla, senior vice president of products and technology at AOptix. He says a faster way to install new capacity is to use his company’s wireless transmission towers to move data at two gigabits per second. Pusarla says the service is particularly attractive to wireless carriers, whose customers have growing appetites for mobile data. Many U.S. providers are currently scrambling to install fiber to replace the copper cables that still link up around half of all cellular towers, he says, but progress has been slow and costly. In the suburbs of New York City, the cost of installing a single kilometer of new fiber can be $800,000, says Pusarla. AOptix technology takes the form of a box roughly the size of a coffee table with an infrared laser peering out of a small window on the front, and a directional millimeter wave radio beside it. The two technologies form a wireless link with an identical box up to 10 kilometers away. A series of such connections can be daisy-chained together to make a link of any length. AOptix teamed up the laser and radio links to compensate for weaknesses with either technology used

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TELECOM: Broadcast With Light - This Technology Is For Sale

You can acquire this fully functioning technology. Interested? CONTACT US

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Beat Wi-fi by hundreds of miles...

Invest, license or purchase. Read More >>> PATENTED LI-FI LIGHT-CASTING MAIN Rev. 2.3

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TELECOM: Laser Antenna For Light-Casting In Specific Circumstances

Ask Us About Deploying This Technology:

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Laser Antenna For Light-Casting In Specific Circumstances

Overview

The Laser Antenna is a block capable of establishing a communication link between units. Contrary to the Antenna, it does not broadcast the ship/station name of the specific systems it is on, giving an advantage on P2P servers - communication between two different locations without revealing the position of either. The Laser Antenna can also relay the signal of other antennae within its range as long as another Antenna or Laser Antenna are present within the same system.

Usage

Unlike the Antenna, the Laser Antenna does not need to broadcast its location.

Remote Access

The laser antenna functions similar to that of Antenna block in which you can control remotely from extreme distances.   INFRARED LIGHT DEPLOYMENTS Infrared signals, with frequencies from 300 GHz to 400 GHz can be used for communication. Infrared signals cannot penetrate walls without a Light-Casting Thrower. This advantageous characteristic prevents interference between one system and another: a short-range communication system in one room cannot be affected by another system in the next room. When we use our infrared remote control, we do not interfere with the use of the remote by our neighbors. No licensing is required for infrared signals, that is, no frequency allocation issues with infrared signals  

  • Infrared (or milimeter) waves characteristics :
                • Used by remote controls for TV, VCRs, etc.
                • Cheap and easy to build.
                • Straight line, no obstacles - even more so than microwaves.
                • Used for wireless LANs within a room.
              • Applications of Infrared
                • Infrared signals can be used for short-range communication in a closed area using line-of-sight propagation.
                • The infrared band, almost 400 THz, has an excellent potential for data transmission.
                • The Infrared Data Association (IrDA), an association for sponsoring the use of infrared waves, has established standard for using these signals for communications between devices such as keyboards, mice, PCs, and printers.
                • For example, some manufactures provide a special port called the IrDA port that allows a wireless keyboard to communicate with a PC.
    1. Satellite Communication

Not so long ago, satellites were exotic, top-secret devices. They were used primarily in a military capacity, for activities such as navigation and espionage. Now they are an essential part of our daily lives. We see and recognize their use in weather reports, television transmission by DIRECTV and the DISH Network, and everyday telephone calls. In many other instances, satellites play a background role that escapes our notice :

  • Some newspapers and magazines are more timely because they transmit their text and images to multiple printing sites via satellite to speed local distribution.
  • Before sending signals down the wire into our houses, cable television depends on satellites to distribute its transmissions.
  • Guided Missiles use the satellite-based Global Positioning System (GPS) to track the proper destination.
  • Emergency radio beacons from downed aircraft and distressed ships may reach search-and-rescue teams when satellites relay the signal.

What is a Satellite ? Satellite is basically any object that revolves around a planet in a circular or elliptical path. The moon is Earth's original, natural satellite, and there are many manmade (artificial) satellites, usually closer to Earth. The path a satellite follows is an orbit. In the orbit, the farthest point from Earth is the apogee, and the nearest point is the perigee. Artificial satellites generally are not mass-produced. Most satellites are custom built to perform their intended functions. Exceptions include the GPS (Global Positioning System) satellites (with over 20 copies in orbit) and the Iridium satellites (with over 60 copies in orbit). Although anything that is in orbit around Earth is technically a satellite, the term "satellite" is typically used to describe a useful object placed in orbit purposely to perform some specific mission or task. We commonly hear about weather satellites, communication satellites and scientific satellites. The Soviet Sputnik satellite was the first to orbit Earth, launched on October 4, 1957. Some Examples of Artificial satellites :

  • 1957 - launch of SPUTNIK 1, Low Earth orbit (LEO), 200 to 600 km, period 90mins.
  • 1958-64 - early developments mainly related to space race !
  • TELSTAR I elliptical orbit 960 to 6080 km, period 2 hr 38 mins.
  • 1965 - INTELSAT I (Early Bird). First geosynchronous satellite that provided a routine link between USA and Europe for 4 years

INTELSAT - International Telecommunications Satellite Organization. More than 110 countries are members of this organization. The INTELSAT is responsible for providing communication links between its members - hires out a service. In satellite transmission signals travel in straight lines, the limitations imposed on distance by the curvature of the earth are reduced. Satellite communication is an extreme example of line-of-sight radio links. One tower is of height 35600km. Satellite relays allow microwave signals to span continents and oceans with a single bounce. Satellite communication systems use UHF (Ultra High Frequency) or SHF (Super High Frequency) microwaves. This ensures that they penetrate the ionosphere and provides a large bandwidth. A satellite network is a combination of nodes that provides communication from one point on the earth to another. A node in the network can be satellite, an earth station, or an end-user terminal or telephone. Although a real satellite, such as the moon, can be used as a relaying node in the network, the use of artificial satellite is preferred because we can install electronic equipment on the satellite to regenerate the signal that has lost its energy during travel. The relay function of the satellite communications system is to receive the up-link signal from the ground, amplify it, change its frequency and retransmit it to the ground. Another restriction on using natural satellites is their distances from the earth, which create a long delay in communication. Satellite can provide transmission capability to and from any location on earth, no matter how remote. This advantage makes high quality communication available to undeveloped parts of the world without requiring a huge investment in ground-based infrastructure. Physical description

  • Communication satellite is a microwave relay station between two or more ground stations (also called earth stations).
  • Satellite uses different frequency bands for incoming (uplink) and outgoing (downlink) data.
  • A single satellite can operate on a number of frequency bands, known as transponder channels or transponders.
  • Geosynchronous orbit (35,784 km).
  • Satellites cannot be too close to each other to avoid interference : This limits the number of available satellites.

Transmission characteristics

  • Optimum frequency range in 1 to 10 GHz.
  • Below 1 GHz, significant noise from galactic, solar, and atmospheric noise, and terrestrial electronic devices.
  • Most satellites use 5.925 to 6.425 GHz band for uplink and 4.2 to 4.7 GHz band for downlink.
  • Propagation delay of about a quarter second due to long distance.
  • Problems in error control and flow control.
  • Inherently broadcast, leading to security problems.

Orbits An artificial satellite needs to have an orbit, the path in which it travels around the earth. Geosynchronous orbits (also called synchronous or equatorial-orbit) are orbits in which the satellite is always positioned over the same spot on Earth. A geosynchronous orbit is one for which the orbital period of the spacecraft is the time taken for the Earth to complete 360o rotation. Geostationary orbits This is a special case of the geosynchronous orbit. In such an orbit the satellite remains above the same point on the ground all the time. Geostationary orbits are 36,000 km from the Earth's surface. At this point, the gravitational pull of the Earth and the centrifugal force of Earth's rotation are balanced and cancel each other out. Centrifugal force is the rotational force placed on the satellite that wants to fling it out into space. Many geostationary satellites are above a band along the equator, with an altitude of about 22,223 miles, or about a tenth of the distance to the Moon. The "satellite parking strip" area over the equator is becoming congested with several hundred television, weather and communication satellites ! This congestion means each satellite must be precisely positioned to prevent its signals from interfering with an adjacent satellite's signals. Television, communications and weather satellites all use geostationary orbits. Geostationary orbits are why a DSS satellite TV dish is typically bolted in a fixed position. The scheduled Space Shuttles use a much lower, asynchronous (or inclined) orbit, which means they pass overhead at different times of the day. Other satellites in asynchronous orbits average about 400 miles (644 km) in altitude. In a polar orbit, the satellite generally flies at a low altitude and passes over the planet's poles on each revolution. The polar orbit remains fixed in space as Earth rotates inside the orbit. As a result, much of Earth passes under a satellite in a polar orbit. Because polar orbits achieve excellent coverage of the planet, they are often used for satellites that do mapping and photography Artificial  satellites  which orbit the earth follow the same laws that govern the motion of the planets around the sun. Johannes Kepler (1571-1630) was derived law called as Kepler’s law, describes planetary motion. The period of a satellite, the time required for a satellite to make a complete trip around the earth, is determined by Kepler’s law, which defines the period as a function of the distance of the satellite from the center of the earth. Period = C  distance1.5 Where C is a constant approximately equal to 1 /100. The period is in seconds and the distance in kilometers.

  • Example 1 : What is the period of the moon according to Kepler’s law ?

Solution : The moon is located approximately 3,84,000 km above earth. The radius of the earth is 6378 km. Period = C  distance1.5 =(1/100)  (3,84,000 + 6378) 1.5 =24,39,090 sec =1 month

  • Example 2 : According to Kepler’s law, what is period of a satellite that is located at an orbit approximately 35,786 km above the earth?

Solution : Period = C  distance1.5 =(1/100)  (35,786 + 6378) 1.5 =86,579 sec =24 hrs This means that a satellite located at 35,786 km has a period of 24 hrs, which is the same as the rotation period of the earth. A satellite like this is said to be stationary to the earth. 4.6 Geostationary Satellite The point 36,000 km from the Earth's surface, the gravitational pull of the Earth and the centrifugal force of Earth's rotation are balanced and cancel each other out. Centrifugal force is the rotational force placed on the satellite that wants to fling it out into space. Many geostationary satellites are above a band along the equator, with an altitude of about 22,223 miles, or about a tenth of the distance to the Moon. The "satellite parking strip" area over the equator is becoming congested with several hundred televisions, weather and communication satellites ! This congestion means each satellite must be precisely positioned to prevent its signals from interfering with an adjacent satellite's signals. Television, communications and weather satellites all use geostationary orbits. Geostationary orbits are why a DSS satellite TV dish is typically bolted in a fixed position.

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TELECOM: Build Your Own Light-Phone Prototype

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Build Your Own Light-Phone

Using Open Source Modules, you can build a perpetually upgradeable Light-Phone. Here are some of the instructions for base chassis creation for your project. The Light Phone Team is working on additional modules to constantly expand the features and performance of your device. You can use Arduino, Raspberry Pi, ARM, Cyanogen Mod, Ubuntu Phone and other existing resources to get you going. You are free to use it non-commercially and you may not sell it without paying the legally required licensing fees. One Great Chassis for your Build-It-Yourself version is the Arduino-based chassis. Here is one set of plans for it. CLICK THIS LINK TO GET THE PDF:  Light-Phone #5F CLICK TO DOWNLOAD OR OPEN PDF

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TELECOM: Light-Phone Patents Can Use Light Capability Recently Discovered

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CONTACT US to license this technology

Light-Phone Patents Can Use Light Recently Discovered To Exist in a Previously Unknown Form to Broadcast Internet and Phone

Source Newsroom: Imperial College London

Nature Communications

Newswise — New research suggests that it is possible to create a new form of light by binding light to a single electron, combining the properties of both.

According to the scientists behind the study, from Imperial College London, the coupled light and electron would have properties that could lead to circuits that work with packages of light - photons - instead of electrons.

It would also allow researchers to study quantum physical phenomena, which govern particles smaller than atoms, on a visible scale.

In normal materials, light interacts with a whole host of electrons present on the surface and within the material. But by using theoretical physics to model the behaviour of light and a recently-discovered class of materials known as topological insulators, Imperial researchers have found that it could interact with just one electron on the surface.

This would create a coupling that merges some of the properties of the light and the electron. Normally, light travels in a straight line, but when bound to the electron it would instead follow its path, tracing the surface of the material.

In the study, published today in Nature Communications, Dr Vincenzo Giannini and colleagues modelled this interaction around a nanoparticle - a small sphere below 0.00000001 metres in diameter - made of a topological insulator.

Their models showed that as well as the light taking the property of the electron and circulating the particle, the electron would also take on some of the properties of the light.

Normally, as electrons are travelling along materials, such as electrical circuits, they will stop when faced with a defect. However, Dr Giannini's team discovered that even if there were imperfections in the surface of the nanoparticle, the electron would still be able to travel onwards with the aid of the light.

If this could be adapted into photonic circuits, they would be more robust and less vulnerable to disruption and physical imperfections.

Dr Giannini said: "The results of this research will have a huge impact on the way we conceive light. Topological insulators were only discovered in the last decade, but are already providing us with new phenomena to study and new ways to explore important concepts in physics."

Dr Giannini added that it should be possible to observe the phenomena he has modelled in experiments using current technology, and the team is working with experimental physicists to make this a reality.

He believes that the process that leads to the creation of this new form of light could be scaled up so that the phenomena could observed much more easily. Currently, quantum phenomena can only be seen when looking at very small objects or objects that have been super-cooled, but this could allow scientists to study these kinds of behaviour at room temperature.

 

Tags: Lightphone, lifi, lightcasting, mobile internet, cellular internet, light-casting, laser broadcasting, light broadcasting, laser internet

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TELECOM: LFi Vs. Fiber

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The Latest Threat to Fiber Networks

 

blue-laser-light-technology With apologies to Dr. Evil, I have one simple request: Internet with frickin’ lasers. Lasers are cool. The Internet is cool. Combining the two sounds like one of the best ideas since peanut butter and jelly. But, until recently, the problem was that practical industrial lasers have been more sci-fi than not. Now, though, the technology is real. The military is already using a laser communication system, and like all military projects, it has an appropriate acronym: the Enhanced Air Ground Lasercom System (EAGLS). Aoptix, the company that designed EAGLS, claims its laser Internet technology has the potential for 2-4 Gbps speeds, double to quadruple the current fastest speeds available in this country. Technically, Aoptix wants to deliver Internet via laser and radio, as the two technologies have to work literally side-by-side. Each technology is susceptible to different forms of weather interference so together they provide redundancy. Raindrops can affect radio, but not lasers, and fog can affect lasers, but not radio. The company says their dual transmitters can reliably send data up to 10 kilometers between relay towers already built and in place. And in case you’re wondering, the laser operates on a non-visible portion of the light spectrum, so you won’t have to put up with looking into the Eye of Sauron to get a fast connection. Here’s how the laser portion of the transmission works: [youtube https://www.youtube.com/watch?v=Di3yScA8wXk] Sure It’s Cool, But Why This Particular Wireless Tech? Like other companies with fiber network alternatives, Aoptix sees infrastructure cost savings as the primary benefit of wireless networks over fiber. There aren’t miles and miles of trenches to dig or fiber to lay. EAGLS has proven the technology works, and the fact that it can work with existing infrastructure means that implementing the laser/radio broadband network should be very inexpensive. Three U.S. carriers are currently in talks with Aoptix, and the system is already in use with Car-Sa, an Internet provider in Mexico. Aoptix has even installed a laser/radio link between NASDAQ and the New York Stock Exchange, where an even slightly faster connection can result in increased profits for stock market traders. Unlike other fiber alternatives that require some infrastructure cost, the fact that Aoptix uses existing towers to relay their signals means that this could be a great way to bring high-speed Internet access to rural areas that already have radio and cell towers. Installation should require little more than putting transmitter relays on those towers. It’s Okay to Geek Out a Bit With these real-world trials already under way, it shouldn’t take long to determine whether lasers are the answer to the wireless broadband question. But take a step back, and forget the science. Forget the infrastructure. We live in a world where nothing amazes us anymore, and there’s a company installing lasers that will let us interact and share content faster than ever. Sure, it’s always smart to be a bit skeptical over promises of better mousetraps, sometimes it’s hard not to get excited. Especially when lasers are involved. Commercial Internet by laser isn’t available quite yet, but if you can’t wait until it is, enter your zip code below to see high-speed plans that are available in your area. Image by Andrew Adams/Flickr

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