I thought GPS was spread spectrum which would make it resistant to these kinds of interference? After all, GPS satellites broadcast at the same frequency as each other, that's the genius of how GPS works.
By the time the GPS signal reaches earth it is at a very low power, think milliwatts.
Lets think of it as you trying to eavesdrop on a meeting.
You have your ear pressed on a big thick wooden door that lets very little sound through, you are attempting to hear so you have everything around you very quiet and try your best to hear that very faint sound of your boss talking about the companies plan to fire everyone. Now your co-worker just a cubicle down is on the phone and instead of keeping it down is talking very loudly. It doesn't matter how hard you try to listen for the sound from inside the meeting all you can hear is your co-worker.
Now think of your boss in the meeting as the GPS satellites and your co-worker as this new company.
Unfortunately when it comes to transmitting power, the more you have of it the more likely you are to overpower other signals. This is the same issue that FM transmitters have as mentioned in the article.
Unless we put better band filters on GPS devices and attempt to filter out a very high power signal GPS is going to get lost in the signal that is being transmitted from the ground.
GPS signal strength at Earth's surface is -130dBmW, so that'd be attowatts... A GPS satellite capable of 0dBmW would be truly scary; it'd have about a petawatt of electrical supply.
