Abstract: A method for jointly determining the azimuth angle ? and the elevation angle ? of the wave vectors of P waves in a system comprising an array of sensors, a number of waves out of the P waves being propagated along coherent or substantially coherent paths between a source and said sensors, includes at least the following steps: selecting a subset of sensors from said sensors to form a linear subarray of sensors; applying, to the signals from the chosen subarray, an algorithm according to a single dimension to decorrelate the sources of the P waves; determining a first component w of said wave vectors by applying, to the signals observed on the sensors of the chosen subarray, a goniometry algorithm according to the single dimension w; determining a second component u of said wave vectors by applying a goniometry algorithm according to the single dimension u to the signals from the entire array of sensors; determining ? and ? from w and u.

Abstract: A method for interpolating steering vectors a(?) of a sensor network, the sensor network receiving signals transmitted by a source, characterized in that, for the interpolation of the steering vectors a(?), use is made of one or more omnidirectional modal functions z(?)k where z(?)=exp(j?) where ? corresponds to an angle sector on which the interpolation of the steering vectors is carried out.

Abstract: Method and system for locating one or more transmitters in the potential presence of obstacles in a network comprising a first receiving station A and a second receiving station B that is asynchronous with A. The method includes the identification of a reference transmitter through an estimation of its direction of arrival AOA-TDOA pair (?ref, ??ref) on the basis of the knowledge of the positions of the reference transmitter and of stations A and B, an estimation of the direction of arrival of the transmitter or transmitters and of the reflectors (or estimation of the AOA) on station A, and the correction of the errors of asynchronism between station A and station B by using the reference transmitter and the location of the various transmitters on the basis of each pair (AOAi, TDOAi).

Abstract: A method for jointly determining the azimuth angle ? and the elevation angle ? of the wave vectors of P waves in a system comprising an array of sensors, a number of waves out of the P waves being propagated along coherent or substantially coherent paths between a source and said sensors, includes at least the following steps: selecting a subset of sensors from said sensors to form a linear subarray of sensors; applying, to the signals from the chosen subarray, an algorithm according to a single dimension to decorrelate the sources of the P waves; determining a first component w of said wave vectors by applying, to the signals observed on the sensors of the chosen subarray, a goniometry algorithm according to the single dimension w; determining a second component u of said wave vectors by applying a goniometry algorithm according to the single dimension u to the signals from the entire array of sensors; determining ? and ? from w and u.

Abstract: A goniometry method for one or several diffuse (or distributed) sources is disclosed. The sources or sources having one or more give directions and a diffusion cone. The sources are received by an array of several sensors. The method breaks down the diffusion cone into a finite number L of diffusers. A diffuser has the parameters (?mp, ??mpi, ?mp, ??mpi), associated with it. Directing vectors a(?mp+??mpi, ?mp+??mpi) associated with the L diffusers are combined to obtain a vector (D(?, ?, ??, ??) ? or U(?, ?) ?(??, ??, ?)) dependent on at least one of the incidence and deflection parameters (?, ?, ??, ??) and on the combination vector ?. A MUSIC-type criterion or other goniometry algorithm is applied to the vectors D(?, ?, ??, ??) ? or U(?, ?) ?(??, ??, ?) obtained in order to determine at least one of the incidence parameters ?mp, ?mp, ??mp, ??mp of the associated diffusion cone.

Abstract: Method and system for locating one or more transmitters in the potential presence of obstacles in a network comprising a first receiving station A and a second receiving station B that is asynchronous with A. The method includes the identification of a reference transmitter through an estimation of its direction of arrival AOA-TDOA pair (?ref,??ref) on the basis of the knowledge of the positions of the reference transmitter and of stations A and B, an estimation of the direction of arrival of the transmitter or transmitters and of the reflectors (or estimation of the AOA) on station A, and the correction of the errors of asynchronism between station A and station B by using the reference transmitter and the location of the various transmitters on the basis of each pair (AOAi, TDOAi).

Abstract: A method for interpolating steering vectors a(?) of a sensor network, the sensor network receiving signals transmitted by a source, characterized in that, for the interpolation of the steering vectors a(?), use is made of one or more omnidirectional modal functions z(?)k where z(?)=exp(j?) where ? corresponds to an angle sector on which the interpolation of the steering vectors is carried out.

Abstract: Disclosed is a method and a device to increase the bit rate in a communications system comprising N transmitters (2N) and M receivers (3M), with M greater than or equal to N. The method comprises the following steps. a) simultaneously sending different messages on several of the N (2N) transmitters, b) simultaneously receiving the superimposition of the messages sent during the step a) on several of the M (3M) receivers or reception sensors, c) estimating the characteristics of the transmission channel for each pair constituted by a transmission sensor and a receiver sensor, d) jointly estimating all or at least the majority of the messages received in taking account of the signals as well as the characteristics of the transmission channel. Application to GSM signals and to systems of unicast transmission and multicast transmission, namely multipoint-to-point and multipoint-to-multipoint transmission.

Abstract: A goniometry method for one or several diffuse (or distributed) sources is disclosed. The sources or sources having one or more give directions and a diffusion cone. The sources are received by an array of several sensors. The method breaks down the diffusion cone into a finite number L of diffusers. A diffuser has the parameters (?mp, ??mpi, ?mp, ??mpi), associated with it. Directing vectors a(?mp+??mpi, ?mp+??mpi) associated with the L diffusers are combined to obtain a vector (D(?, ?, ??, ??) ? or U(?, ?) ?(??, ??, ?)) dependent on at least one of the incidence and deflection parameters (?, ?, ??, ??) and on the combination vector ?. A MUSIC-type criterion or other goniometry algorithm is applied to the vectors D(?, ?, ??, ??) ? or U(?, ?) ?(??, ??, ?) obtained in order to determine at least one of the incidence parameters ?mp, ?mp, ??mp, ??mp of the associated diffusion cone.

Abstract: A method and system for detecting and locating at least one mobile in a standby mode using a search device located at a certain altitude above the at least one mobile. A simulation of a cellular network activates the at least one mobile within range of the simulated network. At least one parameter representative of at least one signal transmitted by the activated at least one mobile is determined.

Abstract: Disclosed is a method and a device to increase the bit rate in a communications system comprising N transmitters (2N) and M receivers (3M), with M greater than or equal to N. The method comprises the following steps. a) simultaneously sending different messages on several of the N (2N) transmitters, b) simultaneously receiving the superimposition of the messages sent during the step a) on several of the M (3M) receivers or reception sensors, c) estimating the characteristics of the transmission channel for each pair constituted by a transmission sensor and a receiver sensor, d) jointly estimating all or at least the majority of the messages received in taking account of the signals as well as the characteristics of the transmission channel. Application to GSM signals and to systems of unicast transmission and multicast transmission, namely multipoint-to-point and multipoint-to-multipoint transmission.

Abstract: Disclosed is a method and a device to increase the bit rate in a communications system comprising N transmitters (2N) and M receivers (3M), with M greater than or equal to N. The method comprises the following steps. a) simultaneously sending different messages on several of the N (2N) transmitters, b) simultaneously receiving the superimposition of the messages sent during the step a) on several of the M (3M) receivers or reception sensors, c) estimating the characteristics of the transmission channel for each pair constituted by a transmission sensor and a receiver sensor, d) jointly estimating all or at least the majority of the messages received in taking account of the signals as well as the characteristics of the transmission channel. Application to GSM signals and to systems of unicast transmission and multicast transmission, namely multipoint-to-point and multipoint-to-multipoint transmission. FIGS. 2a, 2B.

Abstract: Disclosed is a method and a device to increase the bit rate in a communications system comprising N transmitters (2N) and M receivers (3M), with M greater than or equal to N. The method comprises the following steps.

Abstract: Method for detection of one or more mobiles using a search device located at a certain altitude above the mobile comprising at least a cellular network simulation step to activate one or more mobiles on standby within range of the signals from the simulated signals and wherein it determines at least a parameter representative of one or more signals transmitted by the activated mobile(s).

Abstract: A method and device for attenuating wideband spurious noises to improve the signal-to-noise ratio of a tracked acoustic signal. Two sensors (1 and 2) are provided, one of which receives the disturbed tracked signal and the other the spurious noises, to feed a plurality of correlation modules (4) via as many spectrum-line filters (3) distributed throughout the useful bandwidth of sensor (1), each of said correlation modules (4) supplying a correction signal and the sum of said correction signals being subtracted from the signal given by sensor (1) to yield a noise-free tracked signal. The invention is applicable to acoustic reception systems used in noisy environments.