Abstract: A method and apparatus for detecting and classifying submerged swimming object from a passive signal generated by, and an active signal reflected from the object. In a first input of a passive mode branch a first signal representative of the passive signal is received. A second signal representative of the active signal is received in a second input of an active mode branch. In the active mode branch, the first signal is processed to generate a first classification estimate output, with first clues, of the most probable class of target for the object. In the passive mode branch, the second signal is processed to generate a second classification estimate output, with first clues, of the most probable class of target for the object. Both estimate outputs are received in a merger, for generating a merged classification estimate output with clues, which is input to a joint classifier that classifies the object.

Abstract: A method and apparatus for detecting and classifying submerged swimming object from a passive signal generated by, and an active signal reflected from the object. In a first input of a passive mode branch a first signal representative of the passive signal is received. A second signal representative of the active signal is received in a second input of an active mode branch. In the active mode branch, the first signal is processed to generate a first classification estimate output, with first clues, of the most probable class of target for the object. In the passive mode branch, the second signal is processed to generate a second classification estimate output, with first clues, of the most probable class of target for the object. Both estimate outputs are received in a merger, for generating a merged classification estimate output with clues, which is input to a joint classifier that classifies the object.

Abstract: In a method and a device for tracking an object (2a), especially a subsea object, while utilizing a mother vessel (1) or an intermediate craft (101) equipped with sonars (3a) for the transmission and reflection of searching rays (3b, 3n) which on a display on the vessel (1) indicate one or more objects (2a) in the subsea search area, there is provided a searching unit (2) which is controlled from the vessel (1), and which comprises at least one transponder/responder (10, 13) or the like, for the transmission of signals corresponding to the searching rays (3b). The signal(s) is registered on the display on the mother vessel (1) and is used for guiding the searching unit (2) towards a selected object (2a) along the searching rays (3b, 3n) of the sonars.