Wireless Home Digital Interface becomes standard

Sony and Samsung, along with Motorola, Sharp and Hitachi, will develop an industry standard around technology from Amimon Ltd. of Israel called WHDI, for Wireless Home Digital Interface.

“If you have a TV in the home, that TV will be able to access any source in the home, whether it’s a set-top box in the living room, or the PlayStation in the bedroom, or a DVD player in another bedroom. That’s the message of WHDI,” said Noam Geri, co-founder of Amimon.

In an effort to create a broad industry group so consumers will be able to buy compatible enabled devices from different manufacturers, Amimon is already selling chips that fulfill part of that promise.

Wireless streaming of high-definition video can be done with the fastest versions of Wi-Fi, a technology already in many homes, but that requires “compression,” or reduction of the data rate, with picture quality degrading as a result.

That problem led to radio technologies research that is faster, requiring less compression. A leading contender is WirelessHD, centered on technology from SiBEAM of Sunnyvale, Calif. It uses an open portion of the radio band, at 60 gigahertz, for ultrafast transmission of uncompressed video, but it could be years away from commercialization. Its range is limited, meaning that it would be used for in-room links rather than whole-house networking, like WHDI.

Another promising wireless technology is ultra-wideband, or UWB. It requires less compression than Wi-Fi, but its range is more limited, generally to in-room networking. Monster Cable Products Inc. plans to introduce a kit that produces a wireless video link using UWB.

Wireless Home Digital Interface is less exotic than either WirelessHD or UWB. It uses a radio band at 5 gigahertz that’s used by some Wi-Fi devices, which means it can take advantage of research in that field. To get around the limitations of the limited bandwidth, Amimon uses a clever trick instead of compression.

Amimon’s chips separate the important components of the video signal, the ones that really make a difference to the viewer, from the less important ones, like tiny variations in color over a small area. It then gives priority to the important parts, while putting less effort into getting the fine nuances to the receiver.

The result of the transmission works over relatively long distances, albeit with lower image quality as the distance increases.