A data-based technique is disclosed that defines the amplitude and phase of acoustic signals for detection as they propagate across an array of sensor elements for each array incident angle of interest. The definitions of the acoustic signals are then used to constrain adaptive noise suppression operating routines from canceling desired acoustic representative of desired incident direction detector. The data-based technique of defining acoustic signals also leads to a greater reduction of noise in directions where signal is not present. The use of this technique within an adaptive-array-beamforming-processor, and more particularly in connection with the provision of data-based steering vectors therefor, results in an improvement in the ability to detect acoustic signals imbedded in noise.

A speech recognition apparatus including an audio cancellation module is disclosed. The module includes an audio input for receiving an audio signal from a microphone. The module also includes at least two audio inputs for receiving audio signals from respective independent audio sources. The audio cancellation module produces a speech signal by canceling two of the independent audio source signals from the microphone signal. A speech recognizer is used to recognize at least part of the speech signal.

A constrained data-adaptive signal rejector suppresses signals received through the side lobes of a sensor array while preserving signals received through the main lobes. A main beam is formed in a typical signal processing architecture. A subset of the original independent sensor signals are paired into auxiliary channels using a weighting scheme that results in a beam pattern having a null in the direction of the beam mainlobe. The auxiliary channels are then used in a traditional multiple sidelobe cancellation architecture to reject unwanted signals.

Sonar method and system for determining and using beamform factors for forming sonar beams approximating an optimum sonar beam for the directional transmission or reception of sonar energy by a sonar phased array system. Optimum maximum and minimum dependent beamform factors are determined from initial beamform factors and an initial parent population of chromosomes is generated, each chromosome including a gene corresponding to a dependent beamform factor and representing an initial candidate beam. Subsequent parent populations are generated by chromosome cloning. A child population is generated from a parent population by exchanging statistically selected pairs of genes and generating a mutated population. A surviving population is selected from the mutated population by a chromosomes comparison. When the surviving population chromosomes meet the criteria, the best match genes of the surviving population are selected for forming a beam. The criteria may be a predetermined number of iterations or a predetermined tolerance difference.