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This never has added up to me. The FCC certainly doesn’t want to license this if it will interfere with GPS. It sounds like Ligado has to prove to the FCC that it will not interfere with GPS. Where is the FAA on this?
This never has added up to me. The FCC certainly doesn’t want to license this if it will interfere with GPS. It sounds like Ligado has to prove to the FCC that it will not interfere with GPS. Where is the FAA on this?
Ligado, in its earlier incarnation as LightSquared demonstrated clearly and convincingly that its proposed plan will disrupt GPS networks for a minimum of a 1400 nm radius of a solo transmitter running at a fraction of its proposed power. Phil Harbin, a venture capitalist behind LightSquared bought GPS guardband frequencies designated low power orbit to earth only, and proposed running high power terrestrial communications. The final blow was the test that clearly demonstrated first order harmonics falling directly in the GPS spectrum would decimate WAAS and gps throughout North America. Lightsquared went bankrupt, but like all bad ideas, Ligato has arisen from its ashes.
I kept my ADF. Still have it.
Money talks. It was a bad idea 10 years ago, it’s a bad idea today. But, helps fill the coffers of the bureaucrats, so, public interest, convenience, or necessity (as defined as the reason for spectrum licenses to be issued) takes a second row to investments, stockholder return, and executive bonuses.
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Wonder why the FCC wouldn’t allow it ten years ago but will now? Oh - yeah, right ?
The group of GPS users are 62 days premature in asking the Senate Committee on Commerce Science and Transportation to block the FCC’s approval of Ligado’s application–depending on what happens tomorrow.
Ever try and take a juicy bone from a dog? Unless things change, the Senate’s lapdogs will never let go…and the American people will get bitten yet again.
Not only aviation, but a whole slew of industries plus almost every personal car uses GPS navigation. You’d think that the auto manufacturers would chime in on this one too. Talk about killing the goose that lays the golden egg!
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The insatiable quest for more and more bandwidth already is creating this exact problem in other services. If you are a mobile user of Sirius/XM Radio you’ve probably noted occasional signal dropouts not attributable to buildings, terrain or thick vegetation. Most often it’s the result of a nearby cellphone tower which, transmitting on a different but nearby frequency, is blasting your XM receiver with a signal level so strong that it desensitizes the poor XM unit. This is of course merely a minor irritation affecting a limited user base. With GPS the consumer user base is much larger and in many cases is using devices that depend on tiny inexpensive integrated chip/antenna receivers that were never designed to function while subjected to high signal levels on nearby frequencies. It’s going to be a fun experiment.
I was surprised to find out that many industries use GPS not for navigation, but for timing. GPS satellites are basically orbiting atomic clocks. Cell-phone towers use this time signal to keep their towers in sync with each other. This allows handling a multitude of calls simultaneously and seamlessly handing them off from one tower to the next as you scoot down the highway at 60mph.
This site gives just an inkling of how many industries use GPS for timing instead of navigation:
https://www.gps.gov/applications/timing/
I’ll stick with the FCC not approving Ligado’s scheme after the test are run.