High-Def Is in the Air
New technologies wirelessly transmit high-definition video.
A trip across the showroom floor at last week’s Consumer Electronics Show (CES) in Las Vegas pointed to a home entertainment trend: bulky cabinets that hold boxy televisions, stereos, and media players are out, and flat-panel displays on walls are in. But as good as those skinny displays look, they still pose the aesthetic and logistical challenge of what to do with the wires connected to them. Now, a handful of companies are racing to outfit televisions, media players, video cameras, and gaming systems with wireless chips that can cut some of those cords.
At CES, SiBeam demonstrated its wireless chipset, which could stream high-definition video and audio from a media player to a television. With SiBeam’s technology, it would be possible to hang a television on a wall and place the media player in the same room, but far away and out of sight, without wiring the two together. In the demonstration, the company sent data from the media player to the television at a rate of two gigabits per second, fast enough for standard high-definition video, which is known as 1080i. But the company’s first commercial chips–available in Panasonic displays in early 2009–will be better. They will transmit data at four gigabits per second, fast enough to stream the highest-quality high-definition video, 1080p.
Wireless data-transfer technologies are already familiar to most people. But Wi-Fi and Bluetooth, the most common, weren’t designed to send and receive as much data as is needed to make a wireless entertainment center possible, explains John Marshall, vice president of sales and marketing at SiBeam and president of Wireless HD, a collection of companies developing technology guidelines for the consumer electronics industry to follow.
Unlike Wi-Fi, which operates in the 2.4-gigahertz range of the electromagnetic spectrum, Wireless HD works in the 60-gigahertz range, a previously unused region that has a significant amount of bandwidth to spare. As a consequence, Wireless HD can transmit over a broad swath of spectrum, between 59 and 66 gigahertz, greatly expanding its data capacity. But transmission in the 60-gigahertz range also poses significant technical challenges.
For one thing, objects, such as walls or people, readily absorb signals at this frequency, says Jeff Gilbert, chief technology officer at SiBeam. This means that if a signal were simply sent from a media player to a display, and someone walked in front of the player, the picture quality would degrade. SiBeam got around this problem by building a radio that uses beam steering, says Gilbert. Unlike Wi-Fi signals, which send data in all directions, SiBeam’s chips create a beam of information and send it directly between two devices–essentially creating a wireless wire. But the chips’ antenna arrays can also route the signal along multiple paths. To ensure that the link between devices is never broken, explains Gilbert, the radio’s software is ready to switch to an alternate path almost instantly. “In less than a millisecond, it can switch directions,” he says.

SiBeam’s beam-steering technology can bounce signals off of surfaces to maintain a wireless link between devices. If the beam is interrupted by an object or a person, the SiBeam chip automatically and instantly reroutes it.
Credit: SiBeam

2 comments. Share your thoughts » 0 comments about this story. Start the discussion »