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2014年1月14日星期二

ABI Research: LED and Visible Light Communications Could be Key to Indoor Location Market

LED/visible light communication technology is one method of establishing a person’s location indoors. While the indoor location market is relatively nascent, companies are already aggressively addressing next-generation, high accuracy (sub-5m) technologies to ensure they are best placed to...


lifi_environment lifi_environment


While GPS (global positioning satellite) technology works well outside to give a person’s location, finding your location indoors requires different technology. LED/visible light communication technology is one method of establishing a person’s location indoors. While the indoor location market is relatively nascent, companies are already aggressively addressing next-generation, high accuracy (sub-5m) technologies to ensure they are best placed to dominate the emerging multi-billion dollar retail technology market. According to ABI research LED/Visible light Communications (VLC) is tantalizingly close to providing huge performance benefits without the usual cost implications.


ABI Research’s latest report examines the case for LED/VLC technologies in the high-accuracy indoor location space. Senior analyst Patrick Connolly commented, “As a standalone location technology, LED/VLC has some inherent problems, including the need for line-of-sight and a complex value chain. But as part of a hybrid solution it becomes indoor location on steroids, offering ubiquitous sub-meter levels of accuracy in three dimensions, and even has the theoretical possibility as a data communications alternative to Wi-Fi, etc.”


Connolly added, “Most implementations under consideration are already compatible with existing smartphone technology today. If this can be incorporated with negligible cost at the infrastructure side as retail stores naturally migrate to LED lighting, it immediately becomes a no-brainer. However, this means it will also require the backing of at least one of the big four LED OEMs.”


ABI research points out that major OEMs, start-ups, and universities are investigating a host of competing technologies including: sensor fusion, audio/ultrasound, magnetic field, UWB and future evolutions of BLE and Wi-Fi, such as Quuppa’s HAIP technology.


Practice director, Dominique Bonte noted, “Despite the inherent barriers, many companies continue to research and develop in the LED/VLC area, because the technology is potentially so powerful. With large companies like Qualcomm, Casio, Motorola (via Bytelight investment) and Intel joining start-ups in this area, there is now the necessary muscle to force this technology into the mainstream.”



ABI Research: LED and Visible Light Communications Could be Key to Indoor Location Market

2013年10月20日星期日

LED light bulb Li-Fi closer - China scientists develops new Li-Fi data transfer technology

LED light bulb Li-Fi closer – China scientists develops new Li-Fi technology: a microChipped 1 watt LED bulb can produce data speeds of up to 150 megabits per second (Mbps), very enough to provide net connectivity to four computers. Compared with an average internet connection speed of 150...


LED light bulb Li-Fi closer – China scientists develops new Li-Fi technology: a microChipped 1 watt LED bulb can produce data speeds of up to 150 megabits per second (Mbps), very enough to provide net connectivity to four computers.



Li-Fi-LED-light-bulb

Li-Fi-LED-light-bulb



Shanghai’s Fudan University has made a breakthrough with the development of “Li-Fi” technology, in which a one watt LED light bulb can help connect four computers to the internet simultaneously. A microChipped 1 watt LED bulb can produce data speeds of up to 150 megabits per second (Mbps), IT professor at Shanghai’s Fudan University Chi Nan said. Current wireless networks have a problem: The more popular they become, the slower they are. Chi Nan has just become the latest to demonstrate a technology that transmits data as light instead of radio waves, which gets around the congestion issue and could be ten times faster than traditional Wi-Fi.


Compared with an average internet connection speed of 150 megabytes per second (Mbps), the new technology — which uses light as a carrier instead of traditional radio frequencies used for Wi-Fi — can also generate speeds as fast as 3.25 gigabytes per second (Gbps), the university said.


In dense urban areas, the range within which Wi-Fi signals are transmitted is increasingly crowded with noise—mostly, other Wi-Fi signals. What’s more, the physics of electromagnetic waves sets an upper limit to the bandwidth of traditional Wi-Fi. The short version: you can only transmit so much data at a given frequency. The lower the frequency of the wave, the less it can transmit.



LiFi-vs-WiFi

LiFi-vs-WiFi



The current wireless broadband connections are expensive and less efficient, said Xue Xiangyang, a professor at the university’s Department of Computer Science. He cited the example of wireless services in mobile phones, where although there are many base stations set up to help increase the signals, efficiency rates are as low as 5%. On the other hand, LED lighting, which could be used to replace traditional devices, can provide a safer and cheaper solution by adding a microchip on the bulb, Xu said.


The Shanghai Committee of Science and Technology asked Fudan University to work on key applications to help develop the information industry last year, and the university will now showcase ten computer samples using the new technology at the Shanghai Industry Expo next month.


Chi Nan, a member of the research team, said that Wi-Fi, which depends on an invisible wave, has the hidden danger of electromagnetic radiation, while with Li-Fi technology, the light spectrum is 10,000 times more than the radio spectrum and it does not require any new infrastructure construction. He added, however, that there is still a long way to go before Li-Fi can be used by thousands of households as it would take time to manufacture a series of products, such as the connection control and chip at a mass production level.


Chi said that Li-Fi should not be treated as a rival to Wi-Fi connection but rather as a complementary technology, as the Li-Fi connection may be disrupted when the light is blocked.


about Li-Fi



Edinburgh University

Edinburgh University’s Prof Harald Haas coined the term “li-fi”



Li-fi, also known as visible light communications (VLC), at these speeds would be faster – and cheaper – than the average Chinese broadband connection. In 2011, Prof Harald Haas, an expert in optical wireless communications at the University of Edinburgh, demonstrated how an LED bulb equipped with signal processing technology could stream a high-definition video to a computer.


He coined the term “light fidelity” or li-fi and set up a private company, PureVLC, to exploit the technology.”We’re just as surprised as everyone else by this announcement,” PureVLC spokesman Nikola Serafimovski told the BBC.


“But how valid this is we don’t know without seeing more evidence. We remain sceptical.”


This year, the Fraunhofer Heinrich Hertz Institute claimed that data rates of up to 1Gbit/s per LED light frequency were possible in laboratory conditions, making one bulb with three colours potentially capable of transmitting data at up to 3Gbit/s.


Unlimited capacity



Li-Fi-light-data-transfer

Li-Fi-light-data-transfer



Li-fi promises to be cheaper and more energy-efficient than existing wireless radio systems given the ubiquity of LED bulbs and the fact that lighting infrastructure is already in place. Visible light is part of the electromagnetic spectrum and 10,000 times bigger than the radio spectrum, affording potentially unlimited capacity.But there are drawbacks: block the light and you block the signal.


However, this is also a potential advantage from a security point of view. Light cannot penetrate walls as radio signals can, so drive-by hacking of wireless internet signals would be far more difficult, if not impossible.


Prof Chi’s research team includes scientists from the Shanghai Institute of Technical Physics at the Chinese Academy of Sciences, the report says.She admitted that the technology was still in its infancy and needed further developments in microchip design and optical communication controls before it could go mass market.Her team is hoping to show off sample li-fi kits at the China International Industry Fair in Shanghai on 5 November, the report said.




LED light bulb Li-Fi closer - China scientists develops new Li-Fi data transfer technology