In geometry, trilateration is the process of determining absolute or relative locations of points by measurement of distances, using the geometry of circles, spheres or triangles.
Trilateration is a widely used method in wireless sensor networks. It both n
-dimensional space, this method can be used to localize a point using n+1
other points.
In a WSN (wireless sensor network) localization problem, the coordinates of the sensors are unknown, but some of the pairwise distances are known. Using those pairwise distances, relative coordinates of the sensors can be calculated, if and only if there are sufficient calculations.
If coordinates of n+1
sensors are known, localization of WSN can be based on those sensors. Those sensors are reffered to as beacon or seed nodes.
Given a weighted and undirected WSN graph G=(V,E)
, vertices represent the sensors and edges represen their adjacencies. Weights of the edges indicate the distance between two sensor nodes.
G' = (V', E')
is localizable if and only if there is a trilateration ordering among E'
.
G'
is either a subset of G
or equal to G
.
Often referred to as triangulation.