Abstract: Radio location finding A method of detecting a radio emission source (2) includes receiving three or more radio signal datasets from three or more respective sensors (3). Each sensor (3) corresponds to a physical location and includes at least one radio receiver (4). The three or more radio signal datasets include one or more directional datasets obtained using a directional antenna (9, 23) or a directional antenna array of the corresponding sensor, and two or more omnidirectional datasets, each obtained using an omnidirectional antenna (9, 22) or an omnidirectional antenna array of the corresponding sensor. The method also includes determining whether an emitter signal (8) within a target frequency range is present in any of the one or more directional datasets.

Abstract: A method (1) for passively locating a radio emission source (2a, 2b) is described. The method includes including receiving radio signal datasets (D) corresponding to each of three of more sensors (3). Each sensor (3) includes at least one radio receiver (4). The method also includes receiving or retrieving a physical location corresponding to each sensor (3). The physical locations define a convex hull (5). The method also includes determining whether an emitter signal (8) within a target frequency range is present in any of the radio signal datasets (D), and assigning any radio signal dataset which comprises the emitter signal as a detection dataset. The method also includes, in response to determining three or more detection datasets, calculating a signal location (r) based on arrival times of the emitter signal and the respective physical locations. The method also includes generating a locus of possible positions based on calculating two or more alternative signal locations.