Hitachi Adopts UWB for 'Wooo' LCD TVs; A First for Japanese TV Manufacturers

Oct 24, 2007
Hiroki Yomogita, Nikkei Electronics
The Wireless Unit receiver
The Wireless Unit receiver
[Click to enlarge image]

Hitachi Ltd has prepared an HDTV video transmission system using UWB wireless networks for its ultra slim "Wooo UT series" LCD TVs, which will be released in mid December 2007.

The system uses UWB for wireless transmission of HDMI signals. The maximum transmission length is about 9m. UWB has already been applied to computer peripherals and some other devices, but this is the first time that UWB is ever employed by a Japanese TV manufacturer.

Data rates reach 160Mbps

A TV monitor unit and a tuner unit (Wooo Station) are separated and normally connected with an HDMI cable in the Wooo UT series products. UWB is used to connect the monitor and tuner units without a cable. Hitachi expects the wireless system will be highly appreciated when hanging the monitor unit on the wall and setting the Wooo Station on the corner of the room, for example.

The wireless system is named the "Wireless Unit." It consists of a transmitter unit that is connected with the Wooo Station and a receiver unit that is connected with the monitor. The transmitter unit compresses and encodes HDMI signals (including HD quality video data), which are then decoded by the receiver unit.

JPEG 2000 is used for video compression coding. The effective maximum data rate between the wireless transceivers is about 160Mbps. Using multiple carrier-based multiband OFDM for UWB transmissions, the system sends and receives data via a band between 4.2GHz and 4.8GHz.

At the presentation, the company showcased a Wireless Unit mockup and set a similarly-shaped prototype, which can actually send and receive data, on the rear side of the showcase, etc.

Hitachi has not specified the manufacturer of the UWB transceiver chip. However, the shape of the mockup displayed at the presentation and the measure that compresses HDMI signals in the JPEG 2000 format are quite similar to those of the system previously disclosed by Tzero Technologies Inc of the US that designs UWB transceiver reference systems and develops compatible chips. Tzero Technologies' system used Analog Devices Inc's codec LSI for JPEG 2000.

The prototype that actually transmitted radio at the presentation had the name of ASUSTek Computer Inc of Taiwan marked on and used an antenna, which appeared to be Omron Corp's resin small antenna. The shape of the antenna, however, may be different when the system is released on the market, said Hitachi.

There is no MSRP for the Wireless Unit but the company expects pricing for a pair of the receiver and transmitter units to be about ¥90,000. Hitachi estimates 10% to 15% of all Wooo UT series purchasers will buy the Wireless Unit as well.

When set on the lower side of the TV's rear surface
When set on the lower side of the TV's rear surface
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The Wooo Station (center) and the Wireless Unit transmitter (right). At this presentation, a prototype that actually transmits radio was located on the rear of the showcase. An antenna can be seen to the left, behind the Wooo Station.
The Wooo Station (center) and the Wireless Unit transmitter (right). At this presentation, a prototype that actually transmits radio was located on the rear of the showcase. An antenna can be seen to the left, behind the Wooo Station.
[Click to enlarge image]
The prototype located on the rear side. The antenna seemed to be Omron's product.
The prototype located on the rear side. The antenna seemed to be Omron's product.
[Click to enlarge image]