Originally Posted by
klevin99
^ yes, the windows. No doubt about it. With my GPS, which picks up much weaker signals in bands (frequencies) similar to cell phones, the nearer I am to windows (on regular aircraft of course) the stronger the signal. It also depends on angle to the window, since GPS signals propagate roughly on line of sight. If I move my GPS away from the window, say a foot below, I lose most or all signals. Middle seat it may work on the tray table (line of sight again) but not below. None of this is any surprise if you understand electromagnetic wave propagation and shielding. As others have said, the fuselage is a great shield.
I can always get a signal at the window seat I may lose it once in a while. Even in the middle seat usually. Once I get to the aisle, I usually get close to nothing. If I recall, GPS wavelength is in the 8inch range so half/quarter can definitely fit through a window. I don't think line of sight is strictly required as I can pickup satellites on the other side of the plane so I must be getting multi-path. I recall getting stuck in the middle on a 777 and still managing to get a gps lock sometimes.
Anyways, yes it's definitely the windows.