Wireless HDTV Interface at 60 GHzWireless HDTV Interface at 60 GHz

The Consumer Electronics show will be in Las Vegas next week, and one of the surprise announcements is that an industry consortium will be displaying a short-range, wireless HDTV interface. Called WirelessHD, the consortium includes Sony, NEC, Toshiba, LG, and Intel, and will be using a new brand of wireless technology.

The Consumer Electronics show will be in Las Vegas next week, and one of the surprise announcements is that an industry consortium will be displaying a short-range, wireless HDTV interface. Called WirelessHD, the consortium includes Sony, NEC, Toshiba, LG, and Intel, and will be using a new brand of wireless technology.The WirelessHD interface is designed to clean up a good part of that rat's nest of cables that lurks behind your home entertainment system. Primarily it is intended to replace the High-Definition Multimedia Interface (HDMI) used to connect set-top boxes, DVD and DVR units to high definition TV displays; in Wireless HD, the devices actually form a small wireless LAN with a controller. The first generation Wireless HD specification supports data rates up to 4 Gbps, though the technology can theoretically support rates as high as 25 Gbps. That will support uncompressed audio and video at up to 1080p resolution and 24 bit color at 60 Hz refresh rates.

The unique feature of the radio interface is that it operates in the unlicensed 60-GHz band; in North America there is about 7 GHz available between 57 and 64 GHz. Japan has a similar allocation in a slightly different range (59 to 66 GHz), and the EU regulators are considering a similar allocation. Designers have steered clear of the 60-GHz band up until now for a variety of reasons:

* Higher frequency signals lose power more rapidly

* At 60 GHz, oxygen in the atmosphere absorbs some of the energy, further increasing signal loss

* Higher frequency radio signals travel in a linear path normally requiring line of sight between transmitter and receiver

* Up until a few years ago, 60 GHz transmitters could only be built from exotic materials rather than cheap and abundant silicon

As the Wireless HD interface is short-range (up to about 10m), the signal loss is not an issue, and actually helps limit interference with systems in neighboring apartments or homes. Smart beam-forming antenna technology allows non-line of sight operation, and silicon fabrication should make the transmitters cost effective. There is also a built-in security mechanism to appease the content providers.

While primarily a consumer electronics interface, it's only a matter of time before this interface is incorporated in telepresence systems, making them cheaper to install and potentially more portable. I just wish they had this before I drilled all those holes through the wall of my den.