What are the three functional elements of GPS?

• A. Space, Ground, User
• B. Orbit, Control, Receiver
• C. Space, Control, User
• D. Satellites, Control, Equipment

Answer: (C)

The three functional elements of GPS are Space, Control, and User. Space refers to the satellites in orbit that broadcast navigation signals. Control is the ground segment that monitors the satellites, updates their orbital data and timing (ensuring accuracy and integrity). User is the receivers and the processing performed by end users to compute position from the received signals. This three-part architecture—space, control, and user—together enables GPS to function: satellites provide the signals, the control segment maintains the system, and receivers use the signals to determine location. The other descriptions don’t capture all three essential parts: one uses Orbit or Satellites, which is just the space portion; another uses Equipment instead of User, which omits the role of the receiver processing; and one uses Ground instead of Control, which doesn’t name the dedicated control segment responsible for maintenance and timing.