Abstract: The processing of a signal y(t) coming from a microphone of an equipment item including a loudspeaker intended to be supplied a signal x(t), limits an echo effect induced by the microphone capturing a sound emitted by the loudspeaker. This sound and any of its acoustic reflections follow an acoustic path w from the loudspeaker to the microphone. To limit the echo effect, the processing includes determining ?(t) a useful signal s(t) by subtracting from the signal y(t) an estimate of an echo signal x(t)*?(t) given by applying a filter ?(t) to the signal x(t). The filter ?(t) is adaptive by variable step size to account for a change over time in the acoustic path w(t). The adaptive filter ?(t) is produced at each frame k of samples as a function of an update ?W(k) to the acoustic path w for this frame k and by applying a normalization ? satisfying a criterion chosen for minimal variance.

Abstract: A method for interpolating a sound field captured by a plurality of N microphones each outputting the encoded sound field in a form including at least one captured pressure and an associated pressure gradient vector. Such a method includes an interpolation of the sound field at an interpolation position outputting an interpolated encoded sound field as a linear combination of the N encoded sound fields each weighted by a corresponding weighting factor. The interpolation includes an estimation of the N weighting factors at least from: the interpolation position; a position of each of the N microphones; the N pressures captured by the N microphones; and an estimated power of the sound field at the interpolation position.

Abstract: A method for determining operational constraints for a first constellation of non-geostationary satellites transmitting towards a terrestrial station with respect to a second constellation of non-geostationary satellites linked with the station, the constraints comprising a maximum transmission power of the satellites of the first constellation, the method comprising: determining triplets of limit values (?, ?, I/N) of two angles (?, ?) and of an interference-to-noise ratio (I/N), the angles (?, ?) defining a position of a satellite of the first constellation relative to the station and to a satellite of the second constellation and the interference-to-noise ratio being the ratio between interferences transmitted by the first constellation on a link between the station and the satellite of the second constellation and the noise (N) of the link, the determination of the triplets being performed so that a distribution of signal-to-noise and interference ratios (R) aggregated over a time interval is greater than

Abstract: Processing acoustic signals to detect sound sources in a sound scene. The method includes: obtaining a plurality of signals representative of the sound scene, captured by a plurality of microphones of predefined positions; based on the signals captured by the microphones and on the positions of the microphones, applying a quantization of directional measurements of sound intensity and establishing a corresponding acoustic activity map in a sound source localization space, the space being of dimension N; constructing at least one vector basis of dimension less than N; projecting the acoustic activity map onto at least one axis of the vector basis; and searching for at least one local peak of acoustic activity in the map projection, an identified local peak corresponding to the presence of a sound source in the scene.

Abstract: A method for determining operational constraints for a first constellation of non-geostationary satellites transmitting towards a terrestrial station with respect to a second constellation of non-geostationary satellites linked with the station, the constraints comprising a maximum transmission power of the satellites of the first constellation, the method comprising: determining triplets of limit values (?, ?, I/N) of two angles (?, ?) and of an interference-to-noise ratio (I/N), the angles (?, ?) defining a position of a satellite of the first constellation relative to the station and to a satellite of the second constellation and the interference-to-noise ratio being the ratio between interferences (I) transmitted by the first constellation on a link between the station and the satellite of the second constellation and the noise (N) of the link, the determination of the triplets being performed so that a distribution of signal-to-noise and interference ratios (R) aggregated over a time interval is greater

Abstract: A method for determining a maximum transmission power (Pmax, PR, PO) of a non-geostationary satellite (NGSO1, NGSO2) in the direction of a ground station (GSO_SOL), includes the steps of: determining the minimum value of a topocentric angle (?NGSO1, ?NGSO2), formed between the non-geostationary satellite, the ground station and a point of the geostationary arc (ARC_GSO); comparing, in terms of absolute value, the minimum value of the topocentric angle with at least two threshold values (?r, ?o), such that: if it is less than the first threshold (?r), defining the maximum transmission power at a first value (PR), if it is between the first threshold and the second threshold (?o), defining the maximum transmission power at a second value (PO), greater than the first value, or if it is greater than the second threshold, defining the maximum power at a third value (Pmax), greater than the second value; the maximum transmission power values and the thresholds being determined so as to minimize the deviation betwee

Abstract: A method for interpolating a sound field captured by a plurality of N microphones each outputting the encoded sound field in a form including at least one captured pressure and an associated pressure gradient vector. Such a method includes an interpolation of the sound field at an interpolation position outputting an interpolated encoded sound field as a linear combination of the N encoded sound fields each weighted by a corresponding weighting factor. The interpolation includes an estimation of the N weighting factors at least from: the interpolation position; a position of each of the N microphones; the N pressures captured by the N microphones; and an estimated power of the sound field at the interpolation position.

Abstract: A method for determining operational constraints for a first constellation of non-geostationary satellites (CONS_I) transmitting towards a terrestrial station (SV) with respect to a second constellation of non-geostationary satellites (CONS_V) linked with the station, the constraints comprising a maximum transmission power of the satellites of the first constellation, the method includes determining triplets of limit values (?, ?, I/N) of two angles (?, ?) and of an interference-to-noise ratio (I/N), the angles (?, ?) defining a position of a satellite (NGSO_I) of the first constellation relative to the station and to a satellite (NGSO_V) of the second constellation and the interference-to-noise ratio being the ratio between interferences (I) transmitted by the first constellation on a link between the station and the satellite of the second constellation and the noise (N) of the link, the determination of the triplets being performed so that a distribution of signal-to-noise and interference ratios (R) aggre

Abstract: Processing acoustic signals to detect sound sources in a sound scene. The method includes: obtaining a plurality of signals representative of the sound scene, captured by a plurality of microphones of predefined positions; based on the signals captured by the microphones and on the positions of the microphones, applying a quantization of directional measurements of sound intensity and establishing a corresponding acoustic activity map in a sound source localization space, the space being of dimension N; constructing at least one vector basis of dimension less than N; projecting the acoustic activity map onto at least one axis of the vector basis; and searching for at least one local peak of acoustic activity in the map projection, an identified local peak corresponding to the presence of a sound source in the scene.

Abstract: A method for processing sound data for separating N sound sources of a multichannel sound signal sensed in a real medium. The method includes: separating sources to the sensed multichannel signal and obtaining a separation matrix and a set of M sound components, with M?N; calculating a set of bi-variate first descriptors representative of statistical relations between the components of the pairs of the set obtained of M components, calculating a set of uni-variate second descriptors representative of characteristics of encoding of the components of the set obtained of M components; and classifying the components of the set of M components, according to two classes of components, a first class of N direct components corresponding to the N direct sound sources and a second class of M?N reverberated components, by calculating probability of membership in one of the two classes, dependent on the sets of first and second descriptors.

Abstract: A method for determining operational constraints for a first constellation of non-geostationary satellites (CONS_I) transmitting towards a terrestrial station (SV) with respect to a second constellation of non-geostationary satellites (CONS_V) linked with the station, the constraints comprising a maximum transmission power of the satellites of the first constellation, the method includes determining triplets of limit values (?, ?, I/N) of two angles (?, ?) and of an interference-to-noise ratio (I/N), the angles (?, ?) defining a position of a satellite (NGSO_I) of the first constellation relative to the station and to a satellite (NGSO_V) of the second constellation and the interference-to-noise ratio being the ratio between interferences (I) transmitted by the first constellation on a link between the station and the satellite of the second constellation and the noise (N) of the link, the determination of the triplets being performed so that a distribution of signal-to-noise and interference ratios (R) aggre

Abstract: A method for determining a maximum transmission power (Pmax, PR, PO) of a non-geostationary satellite (NGSO1, NGSO2) in the direction of a ground station (GSO_SOL), includes the steps of: determining the minimum value of a topocentric angle (?NGSO1, ?NGSO2), formed between the non-geostationary satellite, the ground station and a point of the geostationary arc (ARC_GSO); comparing, in terms of absolute value, the minimum value of the topocentric angle with at least two threshold values (?r, ?o), such that: if it is less than the first threshold (?r), defining the maximum transmission power at a first value (PR), if it is between the first threshold and the second threshold (?o), defining the maximum transmission power at a second value (PO), greater than the first value, or if it is greater than the second threshold, defining the maximum power at a third value (Pmax), greater than the second value; the maximum transmission power values and the thresholds being determined so as to minimize the deviation betwee

Abstract: A method implemented by a processing device for processing an ambisonic content including a plurality of ambisonic components of a plurality of orders defining a succession of ambisonic channels in each of which an ambisonic component is represented. The method includes: frequency filtering of the ambisonic components in a plurality of frequency bands, compiling an ambisonic decoding matrix, processing the ambisonic decoding matrix in order to extract, by matrix dimension reduction, a plurality of ambisonic decoding sub-matrices each associated with an ambisonic order and a frequency band selected for this ambisonic order, respective applications of the decoding sub-matrices to the ambisonic components in each selected frequency band, and a reconstruction, band by band, of the results of said respective applications, in order to deliver a plurality of decoded signals, each associated with a sound source.

Abstract: A method for processing sound data for separating N sound sources of a multichannel sound signal sensed in a real medium. The method includes: separating sources to the sensed multichannel signal and obtaining a separation matrix and a set of M sound components, with M?N; calculating a set of bi-variate first descriptors representative of statistical relations between the components of the pairs of the set obtained of M components, calculating a set of uni-variate second descriptors representative of characteristics of encoding of the components of the set obtained of M components; and classifying the components of the set of M components, according to two classes of components, a first class of N direct components corresponding to the N direct sound sources and a second class of M?N reverberated components, by calculating probability of membership in one of the two classes, dependent on the sets of first and second descriptors.

Abstract: A method implemented by a processing device for processing an ambisonic content including a plurality of ambisonic components of a plurality of orders defining a succession of ambisonic channels in each of which an ambisonic component is represented. The method includes: frequency filtering of the ambisonic components in a plurality of frequency bands, compiling an ambisonic decoding matrix, processing the ambisonic decoding matrix in order to extract, by matrix dimension reduction, a plurality of ambisonic decoding sub-matrices each associated with an ambisonic order and a frequency band selected for this ambisonic order, respective applications of the decoding sub-matrices to the ambisonic components in each selected frequency band, and a reconstruction, band by band, of the results of said respective applications, in order to deliver a plurality of decoded signals, each associated with a sound source.

Abstract: A method and device are provided for filtering digital audio signals using at least one ARMA filter, particularly during a filter change. The method includes the following steps: a step of receiving a first request to change filtering to or from filtering by a first ARMA filter; and, in response to the first request, a step of gradually switching, at each of a plurality of cascaded first filtering blocks, between digital-signal filtering by a first basic filtering cell and digital-signal filtering by another associated basic filtering cell, the first basic filtering cells of the plurality of first filtering blocks factorizing the first filter.

Abstract: A method and device are provided for detecting acoustic shocks in an audio stream. The method includes: breaking down the audio stream into audio frames; analyzing the audio frames in order to assign each audio frame a category value from among a plurality of predefined values; and determining the probability of an acoustic shock occurring in a current frame, based on a sequence of a given length of category values assigned to a set of frames, using a two-state Markov model, defined by a predetermined transition matrix and transmission matrix.

Abstract: Method for calibrating a linearizer and linearized electronic component the method comprises predistortion, in a predistortion linearizer, of a signal upstream of an electronic component to compensate nonlinear distortion. Determining predistortion setting parameters comprises applying a bifrequency test signal to the component and measuring the relative amplitudes of the lines at the output of the component. A variable indicative of the magnitude |Kp| of the AM/PM conversion coefficient of the component is calculated on the basis of these measurements. The predistortion setting parameters are adjusted so as to minimize |Kp|. The method may in particular be implemented in a linearized amplifier device and in an amplifier test bench.

Abstract: The invention is aimed at improving the quality of the filtering by transfer functions of HRTF type of signals (L, R) compressed in a transformed domain, for binaural playing on two channels (L-BIN, R-BIN), using a combination of HRTF filters (hL,L, hL,R) including a decorrelated version (HRTF-C*, HRTF-E*) of a few of these filters. For this purpose, a decorrelation cue is given with spatialization parameters (SPAT) accompanying the compressed signals (L, R). The Decorrelation comprises applying a different phase shift to each subband of the input signal combined with addition of an overall delay. The invention makes it possible to improve the broadening in the binaural rendition of audio scenes initially in a multi-channel format.

Abstract: A method and device are provided for filtering digital audio signals using at least one ARMA filter, particularly during a filter change. The method includes the following steps: a step of receiving a first request to change filtering to or from filtering by a first ARMA filter; and, in response to the first request, a step of gradually switching, at each of a plurality of cascaded first filtering blocks, between digital-signal filtering by a first basic filtering cell and digital-signal filtering by another associated basic filtering cell, the first basic filtering cells of the plurality of first filtering blocks factorizing the first filter.