Patent ID: 8179316

Claim:
A method of passively locating a target in TOA or TDOA mode comprising the steps of: subdividing into blocks a space in which a location area is situated; and iteratively performing on the blocks, until a predetermined criterion is obtained, the steps of: searching within each block for a presence of at least one point belonging to the location area; excluding from the blocks any blocks that do not contain a point that belongs to the location area; resubdividing into subblocks any blocks that contain a point that belongs to the location area; replacing the blocks by the subblocks, wherein each iteration increases an accuracy of defining the location area, and the method further comprises the steps of: forming a current selection from a first block that corresponds to an a priori search space; forming a current list from the first block; iteratively performing the steps of: subdividing each block of a current list into a first, second, third, and fourth adjoining subblocks; searching the first, second, third, and fourth subblocks for at least one point forming part of the location area, to produce searched subblocks; selecting the searched subblocks having at least one point forming part of the location area, to produce selected subblocks; updating the current list to obtain an updated list, by performing the steps of: deleting blocks that have no selected subblocks; and replacing blocks not deleted by the first, second, third, and fourth subblocks to form an updated current list, wherein: the iteratively performed steps comprise a test to compare a resolution of the blocks that constitute the updated current list; and the iteratively performed steps stop when the resolution is greater than a desired resolution.