Bearings-only localization using direction cosines

Algorithms for localizing a target given multiple simultaneous direction measurements to the target (triangulation) are useful for passively localizing emitters. This paper derives an explicit suboptimal least squares solution to 2D and 3D passive localization using direction cosines (a natural output of an antenna array processing algorithm) as well as refinement techniques. A consistent covariance matrix can be obtained using cubature integration.