Looking for Spectrum

http://www.ntia.doc.gov/files/ntia/publications/spectrum_wall_chart_aug2011.pdf

The office of Spectrum Management of the National Communications and Information Administration of the US Department of Commerce produced that informative chart of allocation of the Radio Spectrum  (and you thought that was the FCC’s job!)

A few notes – the table is logarithmic.   Each row of the chart is 10x more than the previous row.    The entire AM radio band is just a bit over 1 Mhz of bandwidth – FM uses 20 Mhz

So the government is looking for spectrum in that map in order to create more wireless broadband available.   The strip at the bottom indicates if the spectrum is controlled by the government (US Military, intelligence and law enforcement, etc…), Private sector (Satellites, Ham Radio, mobile radio, Cell Phones, wireless broad etc…) or a mix of private and government.

1 Ghz = 1,000 Mhz

An absolutely huge part of the spectrum is controlled by NASA (possibly by international treaties)…  when that space probe out past Jupiter wants to talk to earth, it needs a frequency that isn’t competing with some guy using a CB radio.   SETI needs quiet so it can “listen” to outer space.

Lightsquared has been in the news lately – they want to offer 4G internet access and the FCC granted them a license, but the US Military says it is “too close” to the military GPS network

http://www.pnt.gov/interference/lightsquared/

The Issue is not really that Lightsquared is interfering with GPS, but that GPS devices were made assuming there was a wide buffer of empty space around them so they didn’t have to carefully tune the receivers.   You can imagine that your cell phone with GPS is listening to a radio 100s of miles up in space – and that signal is very weak.

Lightsquared’s conditional FCC license is using from 1522-1559 Mhz – they plan to build out a national 4G network making mobile broadband available close to everywhere, which has been a priority of the FCC and the Obama Administration.   GPS goes from 1559-1610 Mhz.

The right wing nutjobs are trying to frame this as the Obama administration wanting to have US Military planes flying into the ground to benefit their friends at Lightsquared.    The frequency is also used by http://www.inmarsat.com/   Inmarsat, a satellite phone company used both by business and military users.   Because 4G systems would essentially be “always on” in the area around their base station, it would interfere with those phones.  Not a problem with a handset in Afghanistan, but a problem in Virginia (maybe)

The problem with spectrum management is everyone in government has a legitimate reason why they need it for some esoteric future contingency, and in most cases you’re talking about global agreements.