GPS technology uses which of the following technique(s) to determine location coordinates?

• A. Triangulation
• B. Trilateration
• C. Dead Reckoning
• D. Inertial Navigation

Answer: (B)

GPS locates you by measuring how far you are from multiple satellites. Each distance defines a sphere around a satellite, and your position is where these spheres intersect. Because the receiver’s clock isn’t perfectly in sync with the satellites, you must solve for four unknowns at once: x, y, z, and the receiver’s clock bias, which requires at least four satellites. This approach is trilateration, since it relies on distances to known points rather than angles. Triangulation would use angles, which GPS does not provide. Dead reckoning and inertial navigation are different techniques that estimate position from motion data, though they can be used alongside GPS in integrated systems.