Global positioning satellite techniques

A better technique is to compute Tab and to apply a correction to the broadcast. A correction for Tab can be computed if the position of both the transmitter and the receiver are known. If the transmitter is stationary, a constant can be used for the transmitter position. If the transmitter is moving (a satellite, for example), it must broadcast its position in addition to broadcasting time. The Global Positiorung System provides the best of both worlds—each satellite broadcasts its position and the receiver can use coordinates from mirltiple satellites to compute its own position. 

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