Abstract: A locating device comprises a memory (10) arranged to receive data concerning the distance between a plurality of anchors and one or more mobile sources at a plurality of locations different to each other. The number of anchors and the number of locations is such that one must be higher than four and is designated as the primary number, and the other higher than ten and is designated as the secondary number. The device further comprises a decomposer (4) arranged to calculate a decomposition, into singular values, of a matrix formed by the product of the Euclidean distance matrix derived from the distance data multiplied by two square matrices, one of which has a size equal to the primary number squared and the other is the transpose of a matrix with a size equal to the secondary number squared.