
Television White Spaces database receives FCC certification - cleverjake
http://blog.google.org/2013/06/television-white-spaces-database.html
======
jleader
Apparently a "database administrator" is a kind of registry of spectrum and
location, keeping track of what devices are using which frequencies in which
places, and so ensuring no overlaps? Based on this description of the proposal
they submitted: [http://googlepublicpolicy.blogspot.com/2010/01/our-
proposal-...](http://googlepublicpolicy.blogspot.com/2010/01/our-proposal-to-
build-and-operate-white.html) and this FCC page:
[http://www.fcc.gov/topic/white-space](http://www.fcc.gov/topic/white-space)

It turns out that I live in one of the largest "black" areas on their map of
channel availability, Los Angeles. The other large black spots are Salt Lake
City and New York. There are also a couple odd black spots in New Mexico that
must be regulatory rather than physical, since they don't have any "gradient"
of decreasing channel availability around them.
[https://www.google.org/spectrum/whitespace/channel/](https://www.google.org/spectrum/whitespace/channel/)
(looks like it's US-only).

ETA: It looks like the NM rectangular black spot is the "Very Large Array" of
radio-telescopes
([http://en.wikipedia.org/wiki/Very_Large_Array](http://en.wikipedia.org/wiki/Very_Large_Array))

------
jauer
This is exciting progress on the (regulatory) future of radio systems in the
US.

In a nutshell, in the past the FCC assigned exclusive use for a slice of
spectrum to a particular user. A while back the FCC established spectrum
ghettos (the ISM band) in 900Mhz, 2.4Ghz, and 5Ghz as a sort of power-limited
free-for-all. This enabled the explosion of personal connectivity that we've
experienced in the past decade.

They are trying a hybrid approach with the TV Whitespace (TVWS) spectrum freed
up from the analog to digital TV conversion (~400-700Mhz). Multiple
competitive databases were commissioned (Google, Spectrum Bridge, Telcordia,
etc). When a TVWS AP powers up it checks for free channels with the database
over the internet (each TVWS AP has a embedded GPS for location-awareness)[1].
This allows for APs to slot in between licensed users (TV Stations) and the
politically connected illegitimate users, cough, I mean key stakeholders, such
as stadiums and churches (wireless microphones).

1: The idea is database operators can charge for access and give you a API key
to put in the radio or something.

The super exciting part comes (if this works to the FCC's satisfaction) when
you can dynamically allocate spectrum that otherwise would have been reserved
for users that rarely use it. E.g. DoD spectrum that is only used during
natural disasters or spectrum used for ship to shore (if you are in the
midwest).

