Li-Fi eyed as complement to Wi-Fi, cellular

Light fidelity, or Li-Fi, is being eyed as a complement to capacity-challenged Wi-Fi and cellular networks, and a spinoff from a major European university earlier this month shipped its first commercial Li-Fi product.

Li-Fi, a moniker used for visible light communication (VLC) technology, delivers wireless data via visible light spectrum instead of radio frequencies and could be used to enable LED light fittings in buildings to connect to a broadband network.

VLC supporters contend that using the vast amounts of readily available free and unlicensed visible light as well as infrared spectrum could not only solve issues of limited and congested RF spectrum but also deliver much faster wireless. Further, Li-Fi is said to over more security than Wi-Fi because VLC signals, unlike RF, cannot penetrate walls, which protects them from interference or hacking from outside their visual range.

A spinoff from Scotland's University of Edinburgh, pureVLC, has been working to commercialize light-based communications. The company, which will change its name to pureLiFi next month, just shipped its first product, an $8,000 unit delivered to an unspecified U.S. healthcare provider, according to the Financial Times.

Dr. Harald Haas demonstrates Li-Fi. (Video source: TED)

Last month, the startup demonstrated that Li-Fi does not require a line-of-sight connection between the transmitter and receiver and can instead operate by using incident light, which includes reflections. PureVLC said it achieved an industry first by demonstrating high-speed Li-Fi from a reflection, streaming four videos in parallel.

Harald Haas, chair of mobile communications at the University of Edinburgh, is also co-founder and chief science officer of pureVLC. He says adding a microchip to a standard LED bulb to make it rapidly blink on and off is key to delivering binary code to a light-sensitive reciever.

"We have completed ground-breaking research demonstrating speeds up to 1.67 Gbps on a single color/LED. By the end of this year, we believe we can achieve 2 Gbps on each of the R, G, B channels, with a target of demonstrating aggregate speeds up to 6 Gbps," Haas announced in August.

He more recently told the Financial Times that pureVLC's products will initially target niche applications. But he said future growth will be driven by an impending RF spectrum capacity crunch that will hit the wireless industry hard in "two or three years" as data-centric services such as video streaming overwhelm existing networks.

However, indoor networking and location-based services are the only VLC technology applications that have so far penetrated the market, according to a report released early this year by research firm MarketsandMarkets."Products for other applications (intelligent traffic management system, in-flight entertainment, and underwater communication) are expected to hit the market by the end of 2013," said the firm.

MarketsandMarkets predicts visual light communication technology revenues will experience an estimated compound annual growth rate (CAGR) of 82 percent from 2013 to 2018, reaching a value of $6.14 billion in 2018.

In addition to pureVLC, other Li-Fi players include U.S. companies ByteLight and  VX System as well as Japanese companies Nakagawa Laboratories and Outstanding Technology. The Financial Times noted that Casio has created Li-Fi applications enabling data exchanges between smartphones, while French company Oledcomm has demonstrated street lights equipped with Li-Fi.

 For more:
- see this Financial Times article (sub. req.)
- see this pureVLC web page

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