Abstract: The invention relates to an audio device for use proximate a user's ears. The audio device includes first and second audio transmitting/receiving devices that are capable of operating in stereo. The audio device may be used within a system for manipulating audio signals received by the device. The manipulation may include processing received audio signals to enhance their quality. The processing may include applying one or more audio enhancement algorithms such as beamforming, active noise reduction, etc. A corresponding method for manipulating audio signals is also disclosed.

Abstract: Disclosed is a video controlled beam steering mechanism for an adaptive filter in a sensor array system that receives input from a target and applies an averaging filter and appropriately steers the beam. An adaptive filter is then used if the SNR of the output of the averaging filter reaches a threshold.

Abstract: The invention relates to an audio device for use proximate a user's ears. The audio device includes first and second audio transmitting/receiving devices that are capable of operating in stereo. The audio device may be used within a system for manipulating audio signals received by the device. The manipulation may include processing received audio signals to enhance their quality. The processing may include applying one or more audio enhancement algorithms such as beamforming, active noise reduction, etc. A corresponding method for manipulating audio signals is also disclosed.

Abstract: The invention relates to a noise canceling audio transmitting/receiving device; a stereo headset with an integrated array of microphones utilizing an adaptive beam forming algorithm. The invention also relates to a method of using an adaptive beam forming algorithm that may be incorporated into a stereo headset. The sensor array used herein has adaptive filtering capabilities.

Abstract: Disclosed is a steerable sensor array that receives input from a target and applies an averaging filter. An adaptive filter is then used if the SNR of the output of the averaging filter reaches a threshold.

Abstract: A headphone system is provided with two earbud headphones and a control module, each fitted with a plurality of light emitting diodes (LEDs). The LEDs may be of many different colors and flash to the beat of the music. Patterns, colors, and intensity may be adjusted based on a user's preferences. The intensity, frequency, and light patterns of the LEDs may change when a threshold level is reached.

Abstract: A sensor array receiving system which incorporates one or more filters that are capable of adaptive and/or fixed operation. The filters are defined by a multiple of coefficients and the coefficients are set so as to maximize the signal to noise ratio of the receiving array's output. In one preferred embodiment, the filter coefficients are adaptively determined and are faded into a predetermined group of fixed values upon the occurrence of a specified event. Thereby, allowing the sensor array to operate in both the adaptive and fixed modes, and providing the array with the ability to employ the mode most favorable for a given operating environment. In another preferred embodiment, the filter coefficients are set to a fixed group of values which are determined to be optimal for a predefined noise environment.

Abstract: An adaptive system and method for reducing interference in a signal received from an array of sensors. Adaptive filters are used to generate cancelling signals that closely approximate the interference present in the received signal. The adaptive filter weights are converted into the frequency domain where the frequency representation values in a selected frequency range are truncated to avoid signal leakage involving narrow band signals. Deodorizing filters are used to produce the cancelling signals having a flat frequency spectrum. Normalized power difference is used limit the operation of the adaptive filters to the case where there is some directional interference to be eliminated.

Abstract: A noise canceling method and apparatus for canceling noise by time domain processing sub-bands of a digital input signal. The input signal is divided into a number of frequency-limited time-domain sub-bands. Each sub-band is then individually processed to cancel noise present in the signal. The noise processing includes exponential averaging of the input, noise estimation, and subtraction processing. The noise subtraction process is simplified by generating a filter coefficient that is exponentially smoothed, hard limited, and multiplied with the input signal to generate the noise processed output for each sub-band. The noise processed bands are then recombined into a digital output signal. Implementation may be effected in software or hardware and applied to various noise canceling and signal processing applications.

Abstract: A threshold detector precisely detects the positions of the noise elements, even within continuous speech segments, by determining whether frequency spectrum elements, or bins, of the input signal are within a threshold set according to current and future minimum values of the frequency spectrum elements. In addition, the threshold is continuously set and initiated within a predetermined period of time. The estimate magnitude of the input audio signal is obtained using a multiplying combination of the real and imaginary part of the input in accordance with the higher and lower values between the real and imaginary part of the signal. In order to further reduce instability of the spectral estimation, a two-dimensional smoothing is applied to the signal estimate using neighboring frequency bins and an exponential average over time. A filter multiplication effects the subtraction thereby avoiding phase calculation difficulties and effecting full-wave rectification which further reduces artifacts.

Abstract: A dual-processing interference cancelling system and method for processing a broadband input in a computationally efficient manner. Dual processing divides the input into higher and lower frequency bands and applies adaptive filter processing to the lower frequency band while applying non-adaptive filter processing to the higher frequency band. Various embodiments are shown including those based on sub-bands, broadband processing with band-limited adaptation, and broadband processing with an external main-channel generator.

Abstract: A system and method for finding the direction of a wave source using an array of sensors. The system includes a sensor array for measuring waves from the wave source, an approximate-direction finder for finding the approximate direction of the wave source in terms of a sensor pair from the sensors, a precise-direction finder for finding the precise direction of the wave source based on the approximate direction found, and a measurement qualification unit for evaluating the validity of the precise direction under a measurement criterion and discarding the measurements if the criterion is not met.

Abstract: A dual-processing interference cancelling system and method for processing a broadband input in a computationally efficient manner. Dual processing divides the input into higher and lower frequency bands and applies adaptive filter processing to the lower frequency band while applying non-adaptive filter processing to the higher frequency band. Various embodiments are shown including those based on sub-bands, broadband processing with band-limited adaptation, and broadband processing with an external main-channel generator.

Abstract: A cellular telephone for reducing background noise comprising a housing having a receiver portion and a speaker portion; the receiver portion having a voice port and a noise port; a microphone isolator located within the receiver portion; at least one noise canceling microphone having a front end and a back end enclosed by the microphone isolator; an windscreen placed in front of the microphone and internally behind the voice port; and an acoustical port to permit a pressure gradient noise porting placed at the back end of the microphone and internally behind the noise port.

Abstract: Disclosed is a transducer for use in a noise cancellation apparatus for reducing background noise. The transducer includes a housing having first microphone means for receiving a first acoustic sound composed of speech originating from an operator operating the apparatus and background noise, and for converting the first acoustic sound to a first signal, and second microphone means arranged at a predetermined angle .phi. in close proximity with respect to the first microphone means for receiving a second acoustic sound composed of substantially the background noise and for converting the second acoustic sound to a second signal. The first and second microphones are connected to a differential amplifier means of the noise cancellation apparatus so as to obtain a signal representing substantially speech. The amplifier means is for receiving acoustic sounds from each microphone and has a first terminal and a second terminal, wherein the second terminal is grounded.

Abstract: A stethoscope for reducing background noise comprising a housing having a receiver portion and an audio output means; the receiver portion having a plurality of noise ports; a microphone isolator located within the receiver portion; a noise canceling microphone having a front end and a back end enclosed by the microphone isolator; an acoustical tube having an acoustical waveguide connected to the microphone isolator for channeling an input signal; a chest piece having a sound diaphragm pickup for receiving the input sound and noise signal connected to acoustic tube to permit a pressure gradient noise porting placed at the back end of the microphone and internally behind the noise port.

Abstract: This invention relates to a method and an apparatus for reducing ambient noise for use with a headset or a boom headset attached to a boom microphone device or the like. The apparatus can include a sensor microphone to detect a background noise signal, a desired input audio transmission, and signal processing means for canceling the noise signals to create an inverted anti-noise signal within an acoustical waveguide located adjacent to the earphone of headset. The method for reducing noise according to this invention is provided by an open loop circuit allowing the input audio signal from an operator or caller to be transmitted to the user's ear without the disturbance of unwanted ambient noise. The method provides adjustments to the gain and/or phase of a noise signal for canceling the noise component detected, within an acoustical waveguide to produce a quiet zone for the desired audio speech to be transmitted.