Problem:The Global Positioning System (GPS): Observables

Problem: The Global Positioning System (GPS): Observables

What is the minimum number of satellites that must be available for a differential solution of latitude, longitude, height and time?

(A) 1
(B) 2
(C) 3
(D) 4

This is problem 24(11-14) from the new second edition of1001 Solved Surveying Problemsby Jan Van Sickle. Reprinted with permission from1001 Solved Surveying Problemsby Jan Van Sickle (1997, 728 pp., Professional Publications Inc.). For details on this and other FLS exam-prep books, call 800/426-1178 or .

Answer: D

The solution of all four variables requires observation of at least four satellites simultaneously.