72 results about "Adaptive beamformer" patented technology

A method and system for rapid adaptive coupling equalization in beamforming-based communication systems, particularly sector-based beamforming systems, provides smooth transitions for AEC when the look direction of the communication system changes and when the acoustic environment varies with time. The coefficients of inactive beamformers are modified in real-time, using adaptive beamforming techniques based on the real-time loudspeaker-coupling signal, in order to force the outputs of inactive beamformers to have the same response to the loudspeaker coupling signal as the active beamformer does.

A noise suppression apparatus selectively uses an adaptive beamformer and fixed beamformer for each frequency. A direction of a null of the fixed beamformer is determined from a direction of a null automatically formed by the adaptive beamformer. Filter coefficients of the adaptive beamformer based on an output power minimization rule are calculated by a minimum norm method using a norm of the filter coefficients as a constraint. The above selection is made based on, for example, a depth of a null automatically formed by the adaptive beamformer in the selection.

This invention relates to a system and method for suppressing external interference in radar data provided by a plurality of sensors from a main sensor array, the data being pre-processed. The noise suppression system includes a first processing module and a second processing module. The first processing module receives the radar data and produces matched radar data while the second processing module receives the radar data and produces mis-matched radar data. The system further includes a beamformer that is in communication with the first processing module and an adaptive beamformer that is in communication with the second processing module and the beamformer. The beamformer receives the matched radar data and produces beamformed matched radar data.

The invention discloses a sub-array-class adaptive digital beam forming device with low side-lobe characteristics, relating to a sub-array-class adaptive digital beam forming device. The purpose of the invention is to solve the problem that the side-lobe performance of the current sub-array-class adaptive digital beam forming device is poor. The forming device is composed of a sub-array-class optimal adaptive beam forming device, a sub-array-class adaptive beam forming device with a direction figure control performance, an adding device and a beam forming device, wherein the sub-array-class optimal adaptive beam forming device is used for generating a sub-array-class optimal adaptive weight vector wopt; the sub-array-class adaptive beam forming device with the direction figure control performance is used for generating a sub-array-class adaptive weight vector wpc with the direction figure control performance; the adding device carries out weighted summation for the adaptive weight vectors wopt and wpc of the two forming devices; and the beam forming device is used for carrying out adaptive interference suppression. The sub-array-class adaptive digital beam forming device is suitable for the field of sub-array-class adaptive digital beam forming.

The invention discloses a mutual coupling correction-based radar array adaptive beamforming method. The method includes the following steps that: a mathematical model of the receiving of Q different direction signals by a uniform circular array of M array elements is established, an expression X<^>(t) of the receiving of Q different direction signals containing noises by the uniform circular array of M array elements and K received signal samples are obtained, and an interference and noise sampling covariance matrix R <~> of a sample matrix XK is calculated; the output power Pout (theta0, phi) of desired signals to be detected of which the incident direction is (theta0, phi) is calculated, C is constructed, and C and the output power Pout (theta0, phi) of the desired signals to be detected of which the incident direction is (theta0, phi) are adopted as optimization equations of a quantity to be solved, and a final optimization equation is obtained; it is determined that the product of C and the ideal steering vector alpha (theta0, phi) of the desired signals to be detected of which the incident direction is (theta0, phi) is equivalent to the product of an M*L-dimensional matrix T corresponding to M elements included in the alpha (theta0, phi) and a mutual coupling vector, and it is determined that the mutual coupling vector is composed of the first L elements in the first row in C; and the solution of c and the solution of C are calculated; and an optimization function is constructed, and a mutual coupling correction-based adaptive beamformer weight vector is calculated.

A hearing aid comprises a) first and second microphones b) an adaptive beamformer filtering unit comprising, b1) a first and second memories comprising a first and second sets of complex frequency dependent weighting parameters representing a first and second beam patterns, where said first and second sets of weighting parameters are predetermined initial values or values updated during operation of the hearing aid, b3) an adaptive beamformer processing unit providing an adaptation parameter representing an adaptive beam pattern configured to attenuate unwanted noise under the constraint that sound from a target direction is essentially unaltered, b4) a third memory comprising a fixed adaptation parameter representing a third, fixed beam pattern, a mixing unit providing a resulting complex, frequency dependent adaptation parameter as a combination of said fixed and adaptively determined frequency dependent adaptation parameters, respectively, and a resulting beamformer for providing a resulting beamformed signal YBF based on first and second microphone signals, said first and second sets of complex frequency dependent weighting parameters, and said resulting complex, frequency dependent adaptation parameter .

An adaptive time delay control system is provided for matching the propagation time delay between two samples of a signal traveling through two independent paths so that they can be coherently combined for additional signal processing functions such as cosite interference cancellers, adaptive interference cancellers and adaptive beam formers. The adaptive time delay control system and associated method advantageously provide improved continuous matching of the two channels over a wider adjustment range while preserving both convergence speed over the full range and minimum jitter upon convergence by using composite autocorrelation functions to control (adjusting) a matching time delay in one channel.

A method and system for operating an ultrasound system is provided. The method comprising estimating a relative motion between a transducer and an imaging subject and controlling an adaptive beamformer system in response to to an estimation of the relative motion.