Blinking lights eyed for new wireless spec

Soon, visible LED lights may be used to "talk" to — or exchange data with — compatible devices as part of a new wireless specification. The IEEE 802.15 Working Group on Wireless Personal Area Networks said the IEEE Standards Board has approved two standards, according to an article in PC Magazine. IEEE 802.15.7-2011 uses visible light as a communications medium while IEEE 802.15.4-2011 is a short-range communications protocol for "personal" networks, the PC Mag article said. While neither protocol will likely have as much impact as IEEE 802.11, the basis for Wi-Fi, they offer interesting possibilities for communications. The 802.15.7-2011 indicates lights could flicker to transfer data from the light to a compatible device, with the flickering at frequencies too quick for the human eye to detect. Citing the IEEE abstract, PC Mag said the standard is capable of delivering data rates sufficient to support audio and video multimedia services. It also considers mobility of the visible link, compatibility with visible-light infrastructures, impairments due to noise and interference from sources like ambient light and a MAC layer that accommodates visible links. "The standard will adhere to any applicable eye safety regulations," it added. PC Mag cited a 2010 report by EE Times that notes that the standard was not designed to cause lights to flicker annoyingly, but to allow lights to be dimmed yet still communicate. Potential applications EE Times cited a graphic designed by Boston University where a car's brake lights connected to a 802.15.7-2011 chip could be used to signal the car behind it to sharply brake in the case of an emergency. But PC Mag said the scope of the second standard is somewhat unclear. "What's unclear, however, is what the 802.15.4-2011 specification covers. One source, however, said that the 802.15.4-2011 specification appeared to concern '6Lowpan,; promoted by the Internet Engineering Task Force as a technology for short-range personal area networks," it said. However, it cited an email sent to the IEEE member list saying the future amendment, also known as 802.15.4m, was described as a method for "large scale device command and control applications." In September 2010, the FCC opened the spectrum previously used by analog television signals, the so-called "white space." — TJD, GMA News