The Global Positioning System is a global satellite navigation system created and maintained by the United States. The Galileo project is a European Union global satellite navigation system serving the same role.

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GPS Satellite - Special Relativity

I'm going through an old relativity assignment, and I've been asked to calculate the time dilation for a satellite which orbits the earth in 12 hours at 26000km from the surface, and travels at a ...
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What will happen when Russia shuts down the GPS stations? [closed]

Russian officials are seriously talking about shutting down US GPS ground stations within their borders and Deputy Prime Minister of Russia tweeted on the subject. What will happen to the GPS? My ...
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What is the longest distance over which echolocation is effective?

Some animals, most notably bats, use echolocation in order to navigate and detect the location and size of objects and prey. This usually takes place over short distances. What are the theoretical ...
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What is the constant $K_1$ in these orbital equations?

I want to compute the derivatives of argument of periapsis and longitude of the ascending node of the orbit of a GPS satellite from the following formula. $$\frac{d\Omega}{dt} = -K \cos{i} \\ ...
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Observations used to derive orbital and timing information required for GPS satellites

Although I have studied GPS receiver position finding procedure in some detail, I am struggling to find enough information to allow me to deduce how the essential highly accurate orbital and time ...
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Calculating Integrated Precipitable Water using GPS

I'm trying to calculate the Integrated Water Vapor (IWV) using GPS data. I'm following the equations in the following publication: GPS Meteorology: Remote Sensing of Atmospheric Water Vapor ...
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GPS Working Principle [closed]

Hand-held GPS units in modern phones identify your location by (A) transmitting their location and time to GPS satellites. (B) receiving location data of GPS satellites. (C) ...
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Gravitational resonances for satellites

I read on the website of European Space Agency that the altitude of Galileo satellites, which is 29600 Km from the center of the Earth, is chosen to avoid gravitational resonances so that station ...
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Is GPS time measuring the proper time on the mean sea level or the GPS station itself?

LeapSecond.com states: Global Positioning System time is the atomic time scale implemented by the atomic clocks in the GPS ground control stations and the GPS satellites themselves. Does GPS ...
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That 10km/day error predicted if GPS satellite clocks not corrected for relativity

Some authorities have stated publicly and without explanation that if the theories of Special and General Relativity were not taken into account in the design of the GPS (by building the satellite ...
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How do GPS devices work?

I have GPS in my phone but I have only a very rough idea of how it works. I have checked the Wikipedia article but that gone over my head (I can not understand that maths and other strange stuff ...
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Why GPS is at LEO?

Why GPS/GLONASS/Galileo satellites are on low earth orbit? Why geostationary orbit is so bad? Sattelites might be placed there 'statically' and more precise... The only problem I can see is ...