Two updates from the ever-delayed land of ultrawideband (UWB): I remember when 2003 was going to be the year of UWB. Then 2004, 2005, 2006, definitely 2007. Well, maybe 2008. Alereon announced today that they have a UWB chipset that will work with allotted frequencies worldwide. This has been a big stumbling block that has been part of the delays of the last year-plus, along with delays in a certification program. (The news is in this Associated Press article.)
After the IEEE group that UWB figured large in disbanded in Jan. 2006, the various firms and associations involved in UWB hoped to get regulatory approval in much of the world in a matter of months. It's taken years, of course, and the array of frequency limitations is surely one advantage in the multi-band approach that the WiMedia Alliance's partial predecessor, the Multi-Band OFDM Alliance took. The multi-band approach allowed the ultrawide stretches of frequency to be subdivided into smaller bands, making it easier to pick and choose which bands to use. (UWB pioneer and now-out-of-the-UWB-business Freescale's "classical" approach used filters to notch out frequencies that couldn't be trod upon, such as the 5 GHz unlicensed range, and that was reportedly unwieldy as an international approach. Freescale disagreed with that characterization when they were still in the business.)
Interestingly, although Alereon announced a year ago that they had U.S.-based UWB chips, this Associated Press article quotes an Alereon spokesperson stating that products using their first chipsets will appear in Wireless USB in the next month or two. Alereon had expected perhaps a February ship date last fall. The new chips from Alereon will appear in products next year.
The Alereon spokesperson says that the top speed of 480 Mbps won't be achievable on early devices, which is news to me, too. I'm expecting some clarification, as that's not what I've heard. Perhaps he's referring to a range and speed issue.
Meanwhile, the AP noted that Belkin had a Wireless USB product on the market, and I nearly wrote the reporter to correct that information. But Belkin appears to have quietly released the Cable-Free USB Hub ($200) months ago. They managed to ship this without a press release. The last mention on their site is a Dec. 4, 2006, press release that has a note that the product won't ship until January.
Reviews date back to March on Amazon.com (which offers it for $220), with three of four reviews offering a single star: two reviewers say that the unit won't work with Mac OS X, and a third notes a lack of Vista support. One of the Mac reviewers got a blue screen of death with XP SP2.
While Wireless USB requires no special drivers for the devices plugged into the remote USB hub, the dongle that connects to a computer has to be recognized as some kind of USB device. Freescale had planned paired dongles initially that would mimic a USB cable, and thus obviate the necessity of host USB drivers.
To clarify on the PHY data rate, the PHY will run at the full 480Mbps that is specified, however, that data rate will not be seen by end users. this is similar to the 54Mbps quoted as the speed of Wi-Fi, yet most of us get somewhere between 20-25Mbps of usable bandwidth.
[Editor's note: Right; I thought some detail was lost in the AP report. USB 2.0's "480 Mbps" in wired form has the same issue, of course; there's always overhead. Wireline networking tends to have much less as a percentage of bandwidth.-gf]