Cutting the Cord on HDTV

Advocates of cordless HDTV continue moving toward their goal of in-home microwave networks capable of transmitting digital video and audio at high speeds.
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WESTCHESTER COUNTY, NY
Advocates of cordless HDTV continue moving toward their goal of in-home microwave networks capable of transmitting digital video and audio at high speeds.

As a step in that direction, IBM and MediaTek recently announced a joint research and development initiative to create ultra-fast chipsets that can wirelessly transmit full-length movies and other HD content to and from a home computer, handheld device, retail kiosk, or television set.

In tandem with this initiative, several wireless standard-setting projects are moving ahead. Will these diverse wireless standards be compatible? And what about concerns over the health risks of such wireless technologies?

Leading the chipset development drive for IBM are experts at the T.J. Watson Research Center. Established in 1961, the Westchester County, N.Y.-based center has a sister lab in Cambridge, Mass., with almost 1,800 people staffing four facilities.


(click thumbnail)The silicon-germanium (SiGe) chips from IBM and MediaTek will be small enough for handheld consumer devices.“We are developing bipolar 60 GHz silicon-germanium chipsets that combine with regular CMOS transistor technology to transmit and receive HD wireless signals,” said Mehmet Soyuer, group manager of the wireless and wireline communications technology department at the Watson labs.

Silicon-germanium (SiGe) chips can be integrated with CMOS logic to form heterojunction bipolar transistors. A bipolar junction transistor usually has three semiconductor terminals used to amplify or switch signals.

LOW CURRENT, HIGH FREQUENCY

The transistors are termed “bipolar” because they use both electrons and “holes.” These holes are created by the absence of an electron from the otherwise full valence band, affecting the speed of the carrier signal. Heterojunction bipolar transistors offer higher forward gain and lower reverse gain than homojunction bipolar transistors, which yield better low-current and high-frequency performance, making SiGe a viable choice for the mixed-signal circuits needed in HDTV.

Soyuer added that the SiGe transmit and receive chips in the chipset each will be about 1.5mm x 2mm in size. Each will drive a semiconductor antenna of close to the same dimensions. A downversion mixer in the chipset will lock the signal loop.

“Since the 60 MHz wavelength is very short, we’ll be able to implement two low-gain 60 MHz antennas into the chipsets with a range of five to 10 meters,” Soyuer said. “This is why chipset applications may include uncompressed HD video.”

The Watson Research Center will develop all elements of the chipset except the baseband chips, “which we don’t do,” said Soyuer. The baseband chips will come from MediaTek, headquartered in Taiwan with subsidiaries in mainland China, India, Korea, Singapore, and Silicon Valley.

Development will not be overnight, however. Soyuer said he expects the chipset to be ready for consumer electronic devices by 2010 or 2011.

SPECS COMING

This timing means the chipset will enter the market after most of the wireless standards-setting projects have offered their specifications for ratification.

The IBM chipset is meant to comply with the specification slated for release in 2008 by the IEEE 802.16.cc Working Group, which is targeting 60 GHz applications, including HD video transfer at both 1080i and 1080p, according to Soyuer. “It’s going to take a while for these types of products to ramp up to high volume, so I don’t think there’s going to be any wireless HD products in the marketplace by 2010, but if there are, the manufacturers still could upgrade to our chipset,” he said.

A specification for wireless HDTV is just one of the 50 projects now in development by the IEEE 802 LAN/MAN Standards Com- mittees, according to Paul Nikolich, chair of the iEEE 802 LMSC, which coordinates the efforts of more than 1,300 people.

For example, the 802.11 wireless LAN working group includes a study of video streaming throughput at rates up to 1 GBps, Nikolich said. The 802.15 wireless working group is concentrating on the 60 GHz physical layer at up to 1 GBps, and another group is tasked with audio-video bridging and related architecture.

Yet IEEE is not the only one playing in the wireless sandbox.

HDTV AT 60 GHz


(click thumbnail)Chips from Amimon would power devices in the unlicensed 2 GHz spectrum.The Israeli company Amimon is leading a drive to promote WHDI (wireless high-definition interface), which seeks to establish a 60 GHz wireless standard capable of delivering uncompressed HD video and audio across an effective range of 100 to 150 feet from sources like a PC or DVD player to any display, such as a flat-panel screen.

“We demonstrated WHDI solutions at CES as well as at shows in Japan and Germany,” said Noam Geri, Amimon co-founder and vice president of marketing and business development. “The key is that WHDI uses a video modem approach as opposed to the data modem approach at the center of the IEEE effort. As a result, we’ve already shipped chipsets to some leading CE manufacturers for products that will be on the shelves by early 2008.”

Geri declined to list the CE manufacturers incorporating WHDI into their products, but did not deny that Motorola may use WHDI in their cable set-top boxes.

“We’re not really competing with any other wireless standards,” said Geri. “We see our efforts as complementary.”

Among those Amimon supposedly complements is the 60 GHz standard now being developed by the WirelessHD consortium, which includes LG, Samsung, Sony, Toshiba and Matsushita (Panasonic and SiBeam). WirelessHD chair John Marshall said using the unlicensed 60 GHz frequency band means no interference with other household devices that typically operate in the 2 to 6 GHz range. The WirelessHD specification, expected to be released by the end of 2007, will enable HD video streaming over distances of up to 32 feet without the need for line-of-sight connection, as with IR remotes.

Marshall said he’s not concerned about consumer protection activists who claim that wireless technology poses a health hazard in the home. “The FCC wanted to conduct a study of how 60 GHz interacted with the human body. They found that for the most part, 60 GHz signals reflect off water, and since the human body is mostly water, the signals will not penetrate tissue. There’s a white paper at the SiBEAM Web site to support all this.”

The main thing, Marshall said, “is that the industry is now looking at a major technology breakthrough with chips smaller than my fingernail that will deliver HDTV without a tangle of cables in the home. That’s historic.”