The WHDI Consortium has finished a spec for running 1080p at 60 GHz and 12 bits over 5 GHz spectrum: It's not Wi-Fi, nor anything remotely like it, but the WHDI spec uses 40 MHz channels in the 5 GHz band to carry the equivalent of 3 Gbps as far as 100 feet. This new spec, based on work from Amimon, which developed the technology, boosts resolution fro 720p in the previous version to 1080p. It also supports HDCP, the digital rights management (DRM) specification that's used with wired HDMI to ensure end-to-end protection of content.
I wrote about the several contending wireless high-definition specifications in contention back in February 2009 for Ars Technica, including this detailed explanation of how the WHDI/Amimon system works.
While 5 GHz Wi-Fi using 40 MHz channels can only claim with 2x2 MIMO and two data streams to deliver a raw data rate of 300 Mbps, WHDI will deliver 3 Gbps. Because they aren't.
From the press release: the new spec "supports the delivery of equivalent video data rates of
up to 3Gbps." That's equivalent.
WHDI uses a clever system of representing visually more important data in the encoding such that it's more likely to get through in the worst circumstances. Ever less significant information is encoded in methods that are ever more susceptible to interface. The more noise, the less insignificant information gets through.
But that's where you have that equivalent: during the best transmission times, the WHDI Consortium's spec will be able to push through what looks like uncompressed 1080p; during the worst, something far lower than that. It's unclear whether best efforts will win the day.
The competitor for WHDI is pretty clearly WirelessHD, backed by SiBeam, which uses 60 GHz millimeter-wave signals for as much as several Gbps (real Gbps, not equivalent) for each of several channels. The 60 GHz signals are limited to within one room, and have some non-line-of-site and obstruction issues; the 5 GHz service can work over longer distances, but the WHDI probably doesn't want to go into any great depth on how rapidly a signal degrades providing an equivalent bandwidth that's far below 3 Gbps.
The WHDI Consortium was set up by Amimon, Hitachi, Motorola, Samsung, Sharp, Sony, and LG Electronics. Those are some pretty big names in the consumer electronics space. The WirelessHD group also, oddly, includes Samsung, Sony, and LG, as well as Philips, Intel, NEC, and Toshiba, and a host of chipmakers including Intel and Broadcom.
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