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diff --git a/www/gps-hacking.html b/www/gps-hacking.html index 9bec6628..4a2ff097 100644 --- a/www/gps-hacking.html +++ b/www/gps-hacking.html @@ -78,13 +78,14 @@ GPS works and ending with architectural suggestions about how to use <h2>How GPS Works</h2> <p>First, the basics of how GPS works. It depends on the fact that -satellite orbits can be modelled accurately. A GPS sensor is a specialized -computer that knows about the orbits of GPS satellites, and in -particular can predict exactly where each satellite will be at any -given time with respect to the fixed Earth. (For those of you who -enjoy such details, what they actually predict is each satellite's -position with respect to an imaginary ellipsoid called the "WGS 84 -geoid" which closely fits the mean sea level of Earth.)</p> +satellite orbits can be modelled accurately. A GPS receiver is a +combination of a radio receiver and computer that receives timing +signals and orbit information from GPS satellites, and in particular +can compute exactly where each satellite will be at any given time +with respect to the fixed Earth. (For those of you who enjoy such +details, what they actually predict is each satellite's position with +respect to a coordinate system known as WGS84 which closely fits the +mean sea level of Earth.)</p> <p>Although the term <strong>GPS</strong> properly refers only to the system operated by the United States Air Force (also |