It has never been a secret that UWB was going to have some difficulty finding a place of its own in the global spectrum. The bands below 6 GHz are pretty crowded and the ones above it offer something of a patchwork of availability when you look at it from a global perspective.
An added difficulty is the problem of designing and building a cost-effective radio that operates at 6 GHz and up. CMOS is just not there yet. But apparently SiGe isif you wish to infer that from the fact that Alereon has a SiGe solution and is sampling its AL5000 chip set now.
Alereon plans to have sample evaluation boards in the third quarter. It's not saying anything too definitive about when production quantities will be available. But it is likely they will be ready before anybody who is using CMOS.
Solving the radio challenge also allows Alereon to address the spectrum challenge in an intelligent way.
By supporting the three band groups between 7.9 and 10.6 GHz, Alereon makes it possible to provide 17 channels for consumers in Japan and Korea (two big markets). Multiple channels are necessary because UWB technology s based on sending information at low power across (you guessed it) a wide, even ultra-wide, spectrum.
UWB in general and Certified Wireless USB in particular have had a tough time getting traction.
At the beginning of this year, Belkin had some widely reported problems with end-user equipment. Since then, there has been a lot of silence in terms of certifications. As far as I know, only Alereon's PHY has been certified by the USB-IF (Universal Serial Bus Implementers Forum).
Right now, it looks to me like we aren't going to see a lot of products using the 3 GHz spectrum alone even though those were the ones most companies were working on. As I understand it, the 3 GHz products were always thought of as being a bridge into the market and that they would be supplanted by 6 GHz products sooner or later.
Now it seems that the 3-gig window of opportunity may be closing. My guess it got even more complicated when chipmakers encountered hesitancy from OEMs who really don't want to go through the same kind of pain Belkin must have experienced.
Even more important as far as future considerations go is the fact that OEMs would much prefer to have one chip set that can handle all the bands right up to 10 GHz. They don't want to be selling products based on one chip set here and another in Japan. For one thing, the cost of buying in smaller quantities is significant. And design costs are greater as well even though they may not be double.