The first trial of a live white space database has completed, and demonstrated that the technology works – even if the people using it need a little more work.

The 45-day trial was run by Spectrum Bridge, and is a necessary precursor to FCC certification as an official white space database. With the trial completed, the FCC could award certification very quickly, in theory allowing the first white space devices to appear on US shelves by the end of 2011.

Not that they'll be consumer shelves initially, but Spectrum Bridge is optimistic that vertical applications will be using white space devices, and its database, by the end of 2011.

White space devices operate in bands not being used locally for TV broadcasting, but they are required to check with an FCC-certified database to see what bands are available locally, and right now there are no FCC-certified databases.

There will, eventually, be around 10 of them, competing to provide device manufacturers with access to the data and additional services. Consumers should be able to buy white space kit bundled with lifetime access to one of the competing databases, hopefully programmed with a backup database too, in case of cloud failure.

Not that there are any white space devices yet, but as they only require a cursory glance from the FCC ("part 15") devices could get approval very quickly.

The Spectrum Bridge trial used live data, and allowed anyone to log on and see which bands were available in which parts of the USA. Only a handful of the 65 ticketed incidence reports (pdf, easy to read and quite interesting too) from the trial involved factual discrepancies, the vast majority arose from users failing to understand what the service was trying to do, which will be harder to fix.

In addition to television broadcasting channels, the white space database lists bands which have been reserved for wireless microphone use locally, and the Spectrum Bridge trial included an interface through which microphone users could register their reservations. That interface caused some confusion, but also hinted at problems yet to come, as many of the tickets were raised by users who wanted to reserve multiple channels, for their exclusive use, forever.

The FCC has said that it (not Spectrum Bridge, nor anyone else) will accept some reservations, but only in special circumstances. Most wireless microphone users will have to stick within the existing (exclusive) allocation, or take their chances with the rest of the white space users. White space spectrum will be free to use, but comes with no guarantees that everyone else won't be trying to use it at the same time.

It's clear from the tickets raised during the trial that not everyone understands that yet, and there will be something of a learning curve before they do. ®

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