Re: Ground Bound?
Yes, I'm pretty sure you're correct; the shape of the affected volume of air-space indicates a ground-based system.
GPS operates on several frequencies between 1.17645 - 1.57542 GHz and requires line-of-sight to receive a signal so any jamming system would need to operate in the same frequency range, give or take a few harmonics, and will also be essentially line-of -sight. As a consequence, if you move away from a ground-based transmitter/jammer, it will fall below the horizon and out of line-of-sight. This effectively raises the floor-elevation of the signal as distance from the transmitter/jammer increases, which is what the map and numbers show.
However, an even worse faux-pas, than getting the basics of the system wrong, in this article is the pathetic attempt at sensationalism by making the ridiculous claim that the FAA are grounding all civil/commercial aircraft in the region concerned, for six of the busiest hours of the day, when the tests are running...
Quote: "The US Federal Aviation Authority (FAA) is warning aircraft to stay a few hundred miles away from the Naval Air Weapons Station at China Lake"
Yes, it's clarified in the next paragraph... Quote: "The FAA has issued a Notice to Airmen (NOTAM) warning [PDF] that on June 7, GPS readouts will be unreliable or nonexistent for..."
But that's not the same as saying that aircraft shouldn't fly in the region, which is what the first quote above says.
Whilst I can forgive the journalist's ignorance regarding the nature of the system being tested, the pathetic attempt at sensationalism is simply insulting in what is supposed to be a tech/science journal; just because your readers enjoy the informal and light-hearted 'tabloid' format it doesn't mean they're stupid.