842107.fig.006a
(a)
842107.fig.006b
(b)
842107.fig.006c
(c)
Figure 6: Triangulation. (a) As few as two bearings from known positions are required to estimate the position of a target. (b) Degenerate case where a third bearing is needed to disambiguate position. (c) Three bearings may not intersect at the same position.