Andrea Electronics Corporation

Andrea Electronics Coporation

Martin Topf

Douglas J Andrea

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. The transducer further includes a transistor means for receiving and amplifying an AC signal representative of the audio input from each microphone; and means for filtering the amplified AC signal from the DC signal, so that the DC signal powers the amplifier means. Also disclosed is a method for calibrating an active noise reduction apparatus including a housing having a speaker to produce an acoustic anti-noise signal in the housing, a microphone to detect an external noise signal, and an amplitude adjustment means to calibrate the acoustic anti-noise signal to create a quiet zone in the housing for operation with an independent electrical assembly, wherein the apparatus is calibrated separately from the electrical assembly. The method includes the steps of: inputting the external noise signal received by the microphone to produce an anti-noise signal; transmitting to the speaker the anti-noise signal having an equal gain and opposite phase response to the external noise signal detected by the microphone; and balancing the gain and phase response of the anti-noise signal by the amplitude adjustment means located in the noise reduction apparatus to match the gain and phase response of the external noise signal to yield a theoretical zero in the quiet zone.

Noise cancellation apparatus

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. The apparatus can also include a noise cancellation microphone transmitter system having a first and second microphone arranged such that the first microphone receives a desired speech input and the background noise present in the vicinity of the speech, and the second microphone receives substantially only the background noise. The background noise from the second microphone is converted into a corresponding electrical signal and subtracted from a signal corresponding to the speech and background noise obtained from the first microphone so as to produce a signal representing substantial the speech.

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/or and 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.

A self-supporting headset worn on the ear of a user without a headband or placed in a stand as a desk-top microphone system by a switch-function installed in the headset. The headset includes a housing which accommodates a receiver, an arcuate earband connected by a spring to the housing and a pivotally connected boom microphone which extends from the housing to near the lips of a user. The earband can have a shape substantially corresponding to human ear structure for placement behind the ear of the user. The arcuate housing is placed over the entire outer ear to transmit audio signals without any need for an ear tube. An earband member can have a female member on the bottom surface so as to connect a member to mate with a male member located on the stand, to thereby secure the headset on the stand. The headset can be equipped with noise cancellation technology to remove background noise for optional use on with telephones, computers, or any the like.

Noise cancellation headset for use with stand or worn on ear

Apparatus for reducing acoustic background noise for use with a telephone handset or a boom microphone device or a boom headset or the like. The apparatus includes first and second microphones which are arranged such that the first microphone receives a desired speech input and the background noise present in the vicinity of the speech, and the second microphone receives substantially only the background noise. The background noise from the second microphone is converted into a corresponding electrical signal and subtracted from a signal corresponding to the speech and background noise obtained from the first microphone so as to produce a signal representing substantially the speech.

Apparatus for reducing acoustic background noise for use with a telephone handset or a boom microphone device or the like. The apparatus includes first and second microphones which are arranged such that the first microphone receives a desired speech input and the background noise present in the vicinity of the speech, and the second microphone receives substantially only the background noise. The background noise from the second microphone is converted into a corresponding electrical signal and subtracted from a signal corresponding to the speech and background noise obtained from the first microphone so as to produce a signal representing substantially the speech.

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Brooklyn, NY, United States of America

Martin Topf