Trilateration is the use of distances (or "ranges") for determining the unknown position coordinates of a point of interest, often around Earth (geopositioning).
The distances or ranges might be ordinary Euclidean distances () or spherical distances (scaled ), as in true-range multilateration; or biased distances (), as in pseudo-range multilateration.
Trilateration or multilateration should not be confused with triangulation, which uses for positioning; and direction finding, which determines the line of sight direction to a target without determining the radial distance.
Terminology
Multiple, sometimes overlapping and conflicting terms are employed for similar concepts – e.g.,
multilateration without modification has been used for aviation systems employing both true-ranges and pseudo-ranges.
["Multilateration (MLAT) Concept of use", International Civil Aviation Organization, 2007][ "Radar Basics", Christian Wolff, undated] Moreover, different fields of endeavor may employ different terms. In
geometry,
trilateration is defined as the process of determining absolute or relative locations of points by measurement of distances, using the geometry of
,
or
. In surveying,
trilateration is a specific technique.
[ Encyclopædia Britannica][ diracdelta ][ free dictionary]
True-range multilateration
Pseudo-range multilateration
