Abstract: The inventive method relates to the field of submarine detection and deals in particular with the problem of detecting low-power acoustic underwater objects by passive detection systems, of the passive drifting buoy type, which are used by maritime patrol systems, for example. The method consists in processing the complex amplitude-azimuth spectrum of an acoustic signal received by a directional buoy. For different target models envisaged, this processing involves associating the complex frequency components of the received signal, located along the time-evolution curve of the frequency of a signal corresponding to a model target, and comparing the modulus and argument variation of these frequency components with the modulus and argument variation over time of the spectral components of the signal corresponding to the model, the processing using both the amplitude and azimuth information contained in the received signal.

Abstract: The inventive method relates to the field of submarine detection and deals in particular with the problem of detecting low-power acoustic underwater objects by passive detection systems, of the passive drifting buoy type, which are used by maritime patrol systems, for example. The method consists in processing the complex amplitude-azimuth spectrum of an acoustic signal received by a directional buoy. For different target models envisaged, this processing involves associating the complex frequency components of the received signal, located along the time-evolution curve of the frequency of a signal corresponding to a model target, and comparing the modulus and argument variation of these frequency components with the modulus and argument variation over time of the spectral components of the signal corresponding to the model, the processing using both the amplitude and azimuth information contained in the received signal.

Abstract: The invention is a process relating to the processing of the signals sent by passive buoys dropped from an aircraft so as to compile EGP (Energy Geographic Plot) maps. The process is split into three steps: the first makes it possible to produce an EGP map of the x,y positions of the noise sources, the second makes it possible to associate the velocities Vx,Vy with certain designated positions and the third makes it possible to eliminate the noise sources regarded as hampering the readability of the maps.

Abstract: The invention is a process relating to the processing of the signals sent by passive buoys dropped from an aircraft so as to compile EGP (Energy Geographic Plot) maps.

Abstract: A method for mapping a maritime zone, in which buoys transmit and receive signals that echo off a target, and are forwarded to a processing base to determine a position and estimate a velocity of a target. The method includes producing a grid for a zone of possible presence; creating blind elliptical zones by deleting direct signals between transmitting and receiving buoys; determining an amplitude and azimuth of a cell; calculating a likelihood index of a cell; calculating a neutral index of a cell; normalizing by the neutral index and performing a base adjustment; multiplying the likelihood indexes for independent observations of buoys; and thresholding of positions to obtain a number of noncontiguous contacts, forming an Active Geographic Plot.

Abstract: The invention consists, after launching (1) a vehicle (9), in guiding (2) the vehicle (9) towards the mine (5; 6) by means of a sonar coupled to a tactical control station (12) of a hunter (8), fulfilling the functions of classification and permanent monitoring of the position of the vehicle (9) relative to the mine (5; 6), in releasing a locating means (13), carried by the vehicle (9), once the vehicle (9) has arrived at a determined distance from the mine (5; 6), making it possible to fulfil a target designation function by interacting with the vehicle (9) and the tactical control station (12) of the hunter (8), then in communicating (3) to the vehicle (9), by means of the tactical control station (12), the navigation parameters necessary for its attack strategy as a function of the type of mines (5; 6) encountered, and its position referenced by the fixed locating means (13), and in destroying (4) the mine (5; 6) according to the attack strategy acquired by the vehicle (9).