The FCC approved White Spaces yesterday - conservatively.
It looks like the rules haven't been published yet (in the Federal Register?), and that will be the definitive answer to a number of lingering questions, such as actual power levels permitted.
I wish I had been able to view the streaming video from the FCC meeting yesterday, but as one commenter put it "bandwidth is a bit scarce in the DC area today". I guess there was something :-) going on yesterday besides the FCC meeting.
The broadcasters and wireless microphone users won a minor victory in that the FCC, for now, requires geolocation database as part of any white space usage. I didn't appreciate the elegance of that solution for fixing the nagging issue of low-power wireless microphone usage and the often-ignored (except by those of us really paying attention) use of portions of the television spectrum for public safety two-way radio. That is, the wireless microphone users, if they register their usage in "the database" (and this database - administration, access, cost, maintenance hasn't been defined) then they'll be as protected as well as a television broadcast station's usage will be protected. The white spaces devices will check "the database" and if they're near a "protected use", including wireless microphones, they won't be able to use that particular portion of spectrum.
The use of beacons was apparently rejected outright.
But the FCC recognized that spectrum sensing has huge potential that's only been provisionally demonstrated and left the door open for vendors and industry to demonstrate when spectrum sensing is actually ready, but with an unusually "open" process of submission of devices, testing, and certification for use/sale. But there will be a feeding frenzy of vendors to do so because with a spectrum sensing system they can eliminate the expense and bother of the devices having to submit to a geolocation database. It will be a real challenge to sense wireless microphones without beacons, but so be it. DSP technology is up to the challenge of surveying the spectrum for such low-power signals; it will just be expensive at first.
The FCC indicates that this authorization of white spaces will lead to new options for providing Broadband Internet Access. I don't think it will, at least any time soon, at least for primary Broadband Internet Access. The white spaces rules, from what little we know at the moment, weren't that favorable. From what little I've gleaned, the power levels permitted at the moment are way too low for reliable, long-range service such as what will be required in rural areas. For that, I fall back on my Amateur Radio background where 25 watts is considered a reasonable power level for simplex communications in the Amateur UHF band (420-450 MHz) of more than a few miles in terrain that's even a little bit uneven. But the FCC also had language that higher-power operation in white spaces might be permitted in the future.
One interesting tradeoff that will take place in the Wireless ISPs is a tradeoff of antenna size. To make use of the relatively low power, they'll have to use focused / beam antennas. But UHF would require a big panel or dish antenna, so they'll start using yagi beams.
More than a few commenters, including Commissioner Martin, and Google's Larry Page, used the phrase "Wi-Fi on steroids", and that's probably the immediate use. It's easy to imagine a "White Spaces Wider-Fi" access point that will finally cover an entire household... or even cluster of homes that isn't subject to the limitations of 902-928 MHz (good spectrum, but only 26 MHz) or 2.4 GHz (83.5 MHz of spectrum, but too easily blocked by physical obstructions).
The FCC also apparently rejected the idea of "licensed-lite" as advocated by WISPA and some other organizations, of a second tier of registration databases for competing white-space users / usage and mandated sharing and interference resolution. I understand why WISPA wanted that... but in the end I think that the FCC did the right thing in rejecting that approach because there's enough "fraught with peril" for a white spaces device to work around television broadcasting and wireless microphone.
All in all a good day... and I think the voters of the US picked the right person for the leading the US into the next four years. A bonus is that he really gets the importance of the Internet.
By Steve Stroh
This article is Copyright © 2008 by Steve Stroh except for specifically-marked excerpts. Excerpts and links are expressly permitted (and encouraged).
This article was written and posted via Broadband Wireless Internet Access (BWIA) ; Sprint Mobile Broadband service using a Sierra Wireless 595U USB modem - 1xEV-DO Rev. A on a MacBook Pro laptop.
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