ABSTRACT
For three known satellite positions on a common reference frame, the receiver coordinates can be computed on that reference frame by the three distances measured. A fourth satellite, however, needs to be observed due to the lack of synchronization between satellite clocks and the receiver clock. e ephemeris data of all 34 satellites are continuously determined by the operational network of control stations at Colorado Springs, Colorado; Ascension Island; Diego Garcia; Kwajalein Atoll; and Hawaii.
