Cutting The HDMI Cord


Wireless HDMI is something everyone wants. But how close are manufacturers to delivering uncompressed full-resolution at an affordable price?

Jan. 18, 2008 — by .(JavaScript must be enabled to view this email address)

A year ago, a few upstarts at CES were showing prototype systems for “Wireless HDMI.”  These companies intended to remove that bulky and expensive wire between your cable box and your big-screen TV by providing a full-rate wireless connection. A year later, there is one shipping product, and a lot more promise that full rate technology will reach the shelves in 2008.

The problem hasn’t become any easier. Uncompressed full-resolution (1080p) signals require a throughput of 3 gigabits per second (Gb/s). Compare that to the puny 54 megabits per second (Mb/s) for 802.11g, or even the 200Mb/s promised for 802.11n. Pushing gigabits of data through the air is quite a challenge, and I saw few implementations that even claimed to be up to it.

At the top of the pyramid are technologies from three small companies you’ve never heard of:  Amimon, Radiospire, and SiBeam. All three had technology on display in suites, and some in booths on the floor. All claim to be sending full-resolution data, but in different ways.

Amimon claimed to send pictures up to 50 feet using multiple 802.11n channels and antennas. Five channels provides them with a maximum throughput of 1Gb/s, or 1/3 of what’s required for 1080p. They promote their method as uncompressed, but admit to doing perceptual coding, sending over only the “important” data, and discarding the “data that you won’t see.”  Amimon WHDI-based products were on display at the Belkin and Sony booths. The Sony product was a simple two-dongle wireless connection shipping late this year (no price info), while the Belkin product had a variety of inputs on the transmitter, and a small receiver module located behind the TV. It’s promised to ship in the second half of 2008, with a retail price of $599.  Bottom line:  Quality may be an issue (no one was showing it on a particularly large monitor), but there may indeed be product on the shelf late this year.

Radiospire is a Massachusetts startup who is trying to do it right. They are using a proprietary technology (they call it AirHook) to push the full picture through the air, using the same spectrum used for wireless USB. At last year’s show they had a prototype showing in the Philips booth that looked pretty good. They have real chips now, and their demo (at 30 ft.) looked quite sharp. They were showing a switcher product with multiple HDMI, component, and S-Video inputs, which they claimed a major CE manufacturer would be shipping in Q3 for under $600. (Philips perhaps?)  Bottom line: Could be the real deal, but still a bit pricy.

SiBeam is a west-coast startup taking a very different route. Using 60 GHz radios for transmission, their goal is a ubiquitous high-speed (4Gb/s) technology embedded in all kinds of audio/video products, to replace all the wires in your home theater system. They are building a consortium of CE manufacturers to adopt their WirelessHD technology and claim to have their first working signal-processing chips. However, all their demos, which also appeared in the Panasonic and Toshiba booths as “technology demonstrations” (no products or pricing), used their RF chips mounted in their older prototype systems. Still, they hope to seed the technology across multiple manufacturers later this year, and build consensus for interoperability standards that must be met on all products. They expect to see the first products go to market in spring of 2009. Bottom Line:  The technology may be promising, but the consortium/standards approach could slow things down considerably (check the history of 802.11n and wireless USB).

The next lower tier of technologies uses heavy compression to reduce the data stream down to around 150Mb/s. This makes it more manageable, but increases cost, and can increase latency (bad for gaming), as well as produce visual artifacts. Samsung has such a product that won Best-of-show in 2007. This year, it was absent from the floor because it was “nothing new,” having been shipping for months embedded in 50” and 58” TVs (models FP-T5094, FP-T5894). Still, with the huge category buzz at this year’s show, you would think they would want to lord their shipping product over everyone else, which makes one wonder how well it works.

At the 2007 show, a company called Tzero Technologies appeared to have beat everyone out by showing a complete working product. A year later nothing has shipped, and rumors of their demise have haunted the press in recent months. Still, their product from last year appeared in the Gefen and Hitachi booths, and they had a 30 ft. demo running in their own suite where their story was definitely upbeat. Hitachi is promising an embedded product (receiver inside the TV) at the end of Q1, but pricing wasn’t available. Gefen still lists their product on their website (pre-order) for $699.

Other contenders with compressed products included LG and Pulselink. Pulselink‘s gear was also being shown by Westinghouse, but only as a “technology demonstration” as they considered the cost too high for consumers.

Finally, a number of companies were talking about using wireless USB to convey the MPEG-2 compressed stream you receive on your cable or satellite box on to your TV. It sounds good in theory, but the signal still has to be decompressed at the set-top box, and the heavy re-compression (to 50 Mb/s or less) can again add cost, delay, and artifacts.

There’s no question that wireless HDMI is something that everyone wants, and this year it seemed like all the major manufacturers felt the need to show something in their booths, even if it was nowhere near a finished product. Still, as products roll out over the next year, the question will be how badly do people want it?  Will they pay many hundreds of dollars, and then settle for less-than-pristine quality?  Or will they wait until the early adopters pick the winners and losers? I don’t really know (I’m just a writer), but I’ll keep you posted over the year and watch how things turn out.

Check out our Photos from the CES Show Floor.

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