WAAS expansion by using Cell towers?


#1

I was wondering if anyone had thought of using Cell towers near airports as GPS locators to enhance accuracy on approaches. I don’t know a heck of a lot about WAAS, so I don’t know if it would be a good idea or not. I just figure a cell tower would be a good location and that their would be enough to make for excellent triangulations.


#2

A WAAS receiver in a plane doesn’t receive its information directly from the ground stations. There are 25 ground stations in North America each with a 200 nm radius. These stations receive general data for GPS satelites, correct it for clock and atmospheric errors, send that data to two master ground stations which further correct the data then send that info to the GEO stationary WAAS satellites which then send it on to your aircraft’s WAAS receiver. More ground stations would help increase coverage, but most of the US is pretty well covered.

Other uses of cell towers could be for Local Area Augmentation System (LAAS). LAAS uses local radio towers sending info directly to the aircraft. LAAS is a standalone unit, separate for WAAS and I haven’t heard any word of it in years.


#3

Cool, thanks for the explanation. I was thinking WAAS worked like LAAS (though I have only heard a bit about LAAS, so don’t know how they got confused).

So, I guess my idea is for LAAS, which it sounds like may not be something they are going to ever budget for if the airlines get control with the new legislation.