What is Triangulation?
Triangulation is a technique for determining the location of an unknown point by measuring angles from two known reference points. It forms the basis of surveying, navigation, and many positioning systems.
How It Works
Baseline
The known distance between two observation points A and B.
d = sqrt((Bx-Ax)^2 + (By-Ay)^2)
Law of Sines
Relates sides and angles of the triangle formed by A, B, and the target.
a/sin(A) = b/sin(B) = c/sin(C)
Target Position
Computed from the baseline direction, angle, and distance.
T = A + dA * (cos(theta), sin(theta))
Applications
Triangulation is used in land surveying, GPS systems, cell tower positioning, astronomy (stellar parallax), and search-and-rescue operations. The method has been used for centuries to create accurate maps.
Limitations
- The two angles plus the angle at the target must sum to 180 degrees.
- If both angles are too small or too large, the result becomes inaccurate.
- The method assumes a flat plane; for large distances, curvature must be considered.
- Measurement errors in angles are amplified when the target is far away.