Abstract: The present invention provides a microphone array including a small number of real microphone that can realize the same characteristics as a microphone array including a large number of real microphones. The microphone array of the present invention includes a plurality of real microphones, at least one virtual microphone, and an estimator for estimating a sound signal to be received by the virtual microphone based on the sound signals received by the real microphones.

Abstract: A system and method for tracking and recognizing multiple desired acoustic signals and processing the multiple signals with a single microphone is disclosed. The microphone includes multiple transducer elements, each of which produces a distinct electrical signal. The electrical signal is converted to a digital signal and beamforming and digital signal processing is performed on the electrical signals. The signals are then analyzed for the presence of speech. In the case where speech is present in multiple signals, the speech containing signals are then mixed for outputting.

Abstract: Two or more microphones receive acoustic signals and generate audio signals that are processed to determine what portion of the audio signals result from (i) incoherence between the audio signals and/or (ii) audio-signal sources having propagation speeds different from the acoustic signals. The audio signals are filtered to reduce that portion of one or more of the audio signals. The present invention can be used to reduce turbulent wind-noise resulting from wind or other airjets blowing across the microphones. Time-dependent phase and amplitude differences between the microphones can be compensated for based on measurements made in parallel with routine audio system processing.

Abstract: A predetermined characteristic of amplification in dependency of the direction (&thgr;) from which acoustical signals are received at two spaced apart acoustical/electrical transducers (1, 2) is formed in that repetitively a mutual delay signal (A10) is determined from the output signals of the transducers and according to the reception delay at the transducers, one (S1) of the output signals is filtered, thereby the filtering transfer characteristic is controlled in dependency of the mutual delay signal (A12). The output signal of the filtering (14) is exploited as electrical reception signal (Sr).

Abstract: A system for the capturing and relay of sounds from a moving object is described. A plurality of microphone units are positioned at various locations on the moving object to capture sounds. Signals are generated based on captured sounds and transmitted from the moving object to a central receiving station. The central receiving station then takes the signals received and processes such signals for transmission to a communications network for broadcasting the sounds to an audience.

Abstract: An adaptive signal processing system for improving a quality of a signal. The system includes an analysis filterbank for transforming a primary information signal in time domain into oversampled sub-band primary signals in frequency domain and an analysis filterbank for transforming a reference signal in time domain into oversampled sub-band reference signals. Sub-band processing circuits process the signals output from the filterbanks to improve a quality of an output signal. A synthesis filterbank can combine the outputs of the sub-band processing circuits to generate the output signal.

Abstract: This invention improves the usability of a portable wireless terminal. According to this invention, a portable wireless terminal provides signal output means 49 for outputting an audio signal to a speaker 6 or to earphones 25 from an earphone jack 16 via a plug 21, and control means 40 for controlling the signal output means 49 to output an arbitrary audio signal or another audio signal to specified speaker 6 and/or earphones 25 at an arbitrary timing when the arbitrary audio signal is being outputted to the speaker 6 and/or earphones 25. Thereby, an audio signal can be outputted to desired speaker 6 and/or earphones 25 that have been arbitrary selected by switching the output means to them without pulling the plug 21 out of the earphone jack 16 when the audio signal is being outputted to the speaker 6 and/or the earphones 25. Thus, the usability of a portable wireless terminal 1 can be improved.

Abstract: A hand microphone and an adaptor module form an assembly which is a peripheral device for a personal computer. The hand microphone is used to control dictation functions to be carried out by the PC. Two separate analog control signal channels are output from the hand microphone and applied, respectively, as X- and Y-axis inputs for the game port on the PC. Control signals carried in the two signal channels are generated by actuating control switches mounted on the hand microphone.

Abstract: Directional sound acquisition is obtained by combining directional sensitivities in microphones with signal processing electronics to reduce the effects of noise received from unwanted directions. One or more microphones having directional sensitivity including a minor lobe pointing in the particular direction of interest and a major lobe pointing in a direction other than the particular direction are used. Signal processing circuitry reduces the effect of sound received from directions of a microphone major lobe.

Abstract: A circular transducer array (30) is provided for use in recording a sound field. The array (30) comprises a plurality of microphones (31a-31h), a digital signal processor (33), frequency compensation filters (34) and a sum and difference network (35). The digital signal processor calculates the Fourier transform of sampled output signals from the transducers to produce a plurality of sound wave components specifying the sound field. The frequency compensation network (34) equalises each component using Bassel functions to flatten the apparent response of the array (30) and the sum and difference network (35) then combines the equalised components to provide a plurality of audio signals which represent the sound field.

Abstract: A microphone comprises a housing; an acoustic-to-electrical signal transducer disposed within the housing, the transducer being operable to generate an analogue audio signal; and a one-bit analogue-to-digital converter disposed within the housing for converting the analogue audio signal into a one-bit digital audio signal for transmission to other, external, audio processing apparatus.

Abstract: So as to shape the spatial amplification characteristic of an acoustical to electrical converter arrangement at least two sub-arrangements (I, II) of converters are provided, generating different spatial amplification characteristics. Frequency domain converted signals ({tilde over (S)}1) which are proportional to the output signals of the sub-arrangement are compared in a unit (39) on respective spectral frequencies (fs) and there is generated at the output of the comparing unit (39) a binary spectral comparison result signal (A39). Signals ({tilde over (S)}2) which are as well proportional to the output signals of the sub-arrangements (I, II) are fed to a switching unit (41). For each spectral frequency (fB) the control signal from unit 39, as a binary spectral signal, controls the spectral amplitude of which of the two input signals ({tilde over (S)}2) is passed to the output (A41) of the switching unit and of the arrangement.

Abstract: An in-car video system and method is provided where a wireless microphone is configured with bi-directional communications capability. In response to a received RF activation signal, the wireless microphone is automatically switched on to capture (and transmit back to the in-car video system) an audio soundtrack that accompanies the images captured by the car-mounted video camera. A wireless microphone controller mounted in the car transmits the RF activation signal to the wireless microphone. The wireless microphone controller is arranged to transmit the RF activation signal when the VCR starts recording.

Abstract: An attention direction of a robot, indicated by a face, eyes or the like thereof, can be aligned with a directivity direction of a microphone array. Specifically, an acoustic signal from a sound source can be captured, and input signals for individual microphones can be generated. A direction of the sound source can be estimated from the input signals. A visual line of the robot, a posture thereof, or both, can be controlled such that the attention direction of the robot coincides with the direction of the sound source. Then, the directivity direction of the microphone array can be aligned with the attention direction. Thereafter, voice recognition can be performed with an input of a delay sum corresponding to the directivity direction.

Abstract: At a beamformer with at least two acoustical/electrical converters (M1, M2) the outputs (A1, A2) thereof are operationally connected to a beamformer unit (12). There signals dependent on signals (S1, S2) arising at said outputs (A1, A2) are co-processed to result in a beamformer output signal (Sa) dependent on both output signals of the converters. Frequency roll-off of the output signal (Sa) is counteracted by establishing a gain mismatch (10) of the two gains between the acoustical input signal (A) on one hand and the inputs to unit 12.

Abstract: A method for controlling audio gain balance in a multi-mode communications device (200) includes providing (201) microphone audio input to the multimode communications device. The audio is supplied to an amplifier gain stage while a dynamic instantaneous energy value of the audio input is computed (203) when in a first operational mode such as an analog mode. A predetermined gain algorithm is processed (207) representing an audio input when in a second mode such as a digital mode using the energy value. The audio gain stage in the multi-mode communications device is then adjusted (209) so that audio gain when in the first mode substantially approximates an audio gain when in an second mode. This provides a consistent audio amplitude output when receiving the first and second modes in a radio receiver.

Abstract: The invention provides a directional optical microphone, including a housing having an open wall portion closed by a membrane attached thereto, the membrane having an outer surface and an inner surface facing the inside of the housing; a first light waveguide accommodated within the housing, having an output end portion for transmitting light towards the inner surface of the membrane, and a second light waveguide having an input end portion for receiving light reflected from the inner surface; the output and input end portions being positioned in close proximity to, and in optical isolation from, each other, and at least one aperture made in a wall of the housing, the aperture having a cross-sectional area of not less than 1 mm2, for admitting sound waves into the housing to impinge on the inner surface of the membrane.

Abstract: The invention relates to an apparatus for picking up sound waves with a separating body and at least two microphones arranged on the separating body. A pick-up which is particularly true to nature is achieved in such a way that the separating body consists of a reverberant material and is provided with a substantially wedge-shaped arrangement, with two separating surfaces which are inclined towards one another at an acute angle, and that the microphones are arranged at a low distance from the separating surfaces.

Abstract: A sound system and method for modeling a sound field generated by a sound source and creating a sound event based on the modeled sound field is disclosed. The system and method captures a sound field over an enclosing surface, models the sound field and enables reproduction of the modeled sound field. Explosion type acoustical radiation may be used. Further, the reproduced sound field may be modeled and compared to the original sound field model.

Abstract: A microphone assembly includes a main plug unit, a voice-activated microphone unit, a throat-vibration-activated microphone unit, and a control circuit coupled to the main plug unit, the voice-activated microphone unit and the throat-vibration-activated microphone unit. The control circuit is operable between a first state, wherein the main plug unit is coupled to the voice-activated microphone unit and is disconnected from the throat-vibration-activated microphone unit, and a second state, wherein the main plug unit is disconnected from the voice-activated microphone unit and is coupled to the throat-vibration-activated microphone unit.

Abstract: A miniature microphone includes a microphone button or capsule mounted in a microphone housing, wherein the microphone housing has front sound entry openings in communication with a front volume and rear sound entry openings in communication with a rear volume, and wherein the front volume is in communication with front sound entry openings of the microphone capsule and the rear volume is in communication with rear sound entry openings of the microphone capsule. A connecting volume is provided between the front volume and the rear volume.

Abstract: A microphone array apparatus includes a microphone array including microphones, one of the microphones being a reference microphone, filters receiving output signals of the microphones, and a filter coefficient calculator which receives the output signals of the microphones, a noise and a residual signal obtained by subtracting filtered output signals of the microphones other than the reference microphone from a filtered output signal of the reference microphone and which obtain filter coefficients of the filters in accordance with an evaluation function based on the residual signal.

Abstract: The present invention relates to a microphone assembly comprising a microphone assembly casing having a sound inlet port and a transducer for receiving acoustic waves through the sound inlet port. The transducer converts the received acoustic waves to analog audio signals. The assembly according to the present invention further comprises an electronic circuit positioned within the microphone assembly casing, said electronic circuit comprising a pre-amplifier and an analog-to-digital converter preferably in form of a sigma-delta modulator so as to convert amplified analog audio signals to digital audio signals.

Abstract: A microphone array apparatus includes a microphone array including microphones, one of the microphones being a reference microphone, filters receiving output signals of the microphones, and a filter coefficient calculator which receives the output signals of the microphones, a noise and a residual signal obtained by subtracting filtered output signals of the microphones other than the reference microphone from a filtered output signal of the reference microphone and which obtain filter coefficients of the filters in accordance with an evaluation function based on the residual signal.

Abstract: A combination of an electret microphone (1) and a sigma-delta A/D converter (9, 5, 7, 8). The sigma-delta A/D converter has a DC feedback loop (8) which provides the bias current (IDC) for the junction FET (2) of the electret microphone. In this way the signal current from the FET (2) can be injected directly into the input integrator (9) of the sigma-delta A/D converter without the need of signal resistors in series with the FET (2).

Abstract: Two or more speakers are used to generate complimentary sound waves within a soundproof cabinet. The sounds generated inside the cabinet are detected by a microphone and sent to an external device for recording or listening purposes. In one embodiment, two speakers are arranged side-by-side and mounted on a panel. The panel serves to section off two chambers within the cabinet. The primary chamber is the chamber toward which the speakers are facing. The secondary chamber is the chamber within which the backs of the speakers are positioned. The speakers are connected to the input signal in reverse polarity of each other. Thus, during operation one speaker is pushing air outward while the other is pulling air inward. This complimentary generation of sound waves alleviates the muffling effect of the small isolated space and allows the speakers to generate sound as though they were in a much larger open area. Thus, the sound picked up by the microphone is very close to the desired “live” sound.

Abstract: A hearing aid has a signal processing unit, an earphone and at least two microphones whose output signals are subtracted from one another in a first difference element in order to achieve a directional microphone characteristic, and a difference element subtracts average values of the output signals of the microphones and supplies a signal to an analysis/control unit for controlling the amplification of the output signal of at least one of the microphones that follows the second difference element. In a method for the operation of a hearing aid having automatic microphone balancing, following formation of average values proceeding from the output signals of the microphones, the deviation of the average values from one another is identified and the amplification of at least one output signal of a microphone is adjusted until coincidence of the average values occurs.

Abstract: A microphone array apparatus includes a microphone array including microphones, one of the microphones being a reference microphone, filters receiving output signals of the microphones, and a filter coefficient calculator which receives the output signals of the microphones, a noise and a residual signal obtained by subtracting filtered output signals of the microphones other than the reference microphone from a filtered output signal of the reference microphone and which obtain filter coefficients of the filters in accordance with an evaluation function based on the residual signal.

Abstract: Improved approaches to control directional processing in multi-microphone processing systems. These approaches operate to control activation/deactivation of directional processing in multi-microphone processing systems. As a result, directional processing can be automatically activated or deactivated based on the amount of interference (e.g., noise) in the listening environment. These approaches are particularly useful for hearing aid applications in which directional noise suppression is important.

Abstract: A sound recording system includes a hand microphone with a plurality of operation switches mounted on the hand microphone. The switches include a record switch. The system also includes a sound recording device which is connected by a signal path to the hand microphone and records sound information generated at the hand microphone. Control circuitry included in the hand microphone and/or in the sound recording device controls operation of the sound recording device on the basis of input signals generated by the user via the operating switch array. If the record switch is actuated for only a brief period of time, a record-lock mode of operation is implemented. If the record switch is actuated for a longer period of time, a momentary-record mode is entered which lasts only as long as the record switch remains in an actuated position.

Abstract: An object of the present invention is to turn microphones accurately and quickly toward a sound source. The first microphone pair is rotated by rotation means and driving means, so that the microphones are equidistant from a sound source. The sound picked up by the microphones is analyzed in a plurality of frequency ranges to obtain delay time components of the arrival of the sound wave. The delay time components are averaged with a prescribed coefficients so that the lower frequency components hardly affects the result of the direction detection. the averaged delay is converted into an angle of direction of the sound source. Thus, the microphones pair is directed in front of the sound source on the basis of the direction angle converted from the averaged delay time.

Abstract: A microphone capsule for an in-the-ear hearing aid is disclosed. The capsule can include a top plate having first and second spaced openings defining front and rear sound inlets, and a directional microphone cartridge enclosing a diaphragm. The diaphragm is oriented generally perpendicular to the top plate and divides the directional microphone cartridge housing into a front chamber and a rear chamber. A front sound passage communicates between the front sound inlet and the front chamber, and a rear sound passage communicates between the rear sound inlet and the rear chamber. Front and rear acoustic damping resistors are associated with the front and rear sound passages. The acoustic resistor pair provides a selected time delay, such as about 4 microseconds, between the front and rear sound passages. The use of two acoustic resistors instead of one levels the frequency response, compared to the frequency response provided by a rear acoustic damping resistor alone.

Abstract: A high quality stereophonic sound enclosure system high resolution intended for computer visual display monitors employing cathode ray tubes (CRTs) having a vertical aperture grill, and methods for construction of same. The aperture grill has a natural frequency centered within the musical scale. The stereo speaker system comprises a ported speaker enclosure within which are mounted two conventional cone speaker assemblies. A stereo audio amplifier and control unit for controlling the audio signals delivered to the speakers is mounted within the speaker enclosure. The speaker enclosure is internally mounted within the monitor with a minimum number of attachment members incorporating vibration isolation material to remove vibration components near the natural frequency of the aperture grill. The speaker enclosure is internally reinforced to reduce structural deformations which contribute to airborne transmitted vibration within the monitor housing when the speaker system is operating.

Abstract: The present invention relates to a directional microphone assembly comprising a front and a rear microphone for compact communication devices, such as hearing aids, mobile phones etc. The present invention integrates most or all electronic processing circuits required to form a directional microphone output signal using a front and a rear microphone signal. Accordingly, the directional microphone assembly according to the present invention occupies less volume compared to traditional microphone assemblies.

Abstract: A method and system for simultaneously controlling a plurality of automatic speech recognition (ASR) systems within the working volume of a room, or for controlling multiple devices as a single unified ASR system. Multiple microphones feed a signal processing system which determines or estimates both a user's location and a user's orientation within a room as the user issues voice commands, and further determines the microphone providing the best signal. Diversity noise cancellation may be further applied to the microphone signals. Based on the apparent direction the user is facing, the system may then enable one of the ASR systems for voice command recognition and/or execution of voice commands. The invention reduces the number of false command executions and improves the performance, accuracy, and ease of use of voice control.

Abstract: A self-contained helmet communication system is arranged to support oral communication by sending sound waves to and receiving sound waves from an unequipped person positioned near a helmet wearer. The helmet communication system includes a protective helmet having an external microphone and speaker mounted on the helmet. The external microphone, responsive to sound waves external to the helmet, provides signals that are coupled to an internal speaker or earphone to provide a representation of the external sound waves to the wearer. An internal microphone, which is responsive to speech of the helmet wearer, provides signals representative of the helmet wearer's speech that are coupled to an external speaker. Additionally included is a signal coupler with dual audio amplifier channels to couple signals representative of external sound waves from the external microphone to the internal speaker, and to couple signals representative of speech of the wearer from the internal microphone to the external speaker.

Abstract: A waterproof microphone and speaker (10) having a waterproof handle (12). A waterproof microphone (14) is securely attached to a top end of the handle (12). At least one microchip (16) is contained within the handle (12). The microphone (14) is electrically connected to the at least one microchip (16). A battery (18) is contained within the handle (12). The battery (18) is electrically connected to the at least one microchip (16). A waterproof ON/OFF control (20) is contained within the handle (12). The ON/OFF control (20) is electrically connected to the at least one microchip (16). A waterproof volume control (22) is contained within the handle (12). The volume control (22) is electrically connected to the at least one microchip (16). A waterproof speaker (28) is contained within the handle (12). The speaker (28) is electrically connected to the at least one microchip (16).

Abstract: An electronic component assembly (102) for an electronic device (100) comprises an electronic component (140), a retainer (142), and an elastomeric connector (144). The electronic device (100) includes a housing (104, 106) and a printed circuit board (PCB) (108) having PCB throughholes (128, 130) and PCB conductive pads (200, 202). The electronic component (140) has a bottom side (146) including substantially planar conductive regions (152, 154) and electrical leads (148, 150) extending therefrom. The retainer (142) positions the elastomeric connector (144) adjacent to the substantially planar conductive pads (152, 154). Electronic component assembly (102) is placed and attached to the PCB (108) by inserting the electrical leads (148, 150) through the PCB throughholes (128, 130) and subsequently clinching the electrical leads (148, 150).

Abstract: A microphone shock mount includes an inner housing, an outer housing extending around the inner housing and top and bottom dampeners which extend between the inner and outer housings. An annular groove is formed in an outer surface of the inner housing adjacent a top thereof and a stepped shoulder is formed in the outer surface of the inner housing adjacent a bottom thereof. A pair of stepped shoulders are formed in an inner surface of the outer housing adjacent a top and bottom thereof. The top and bottom dampeners are ring-shaped with a generally U-shaped cross-section. An annular rib extends inwardly from an inner portion of the top dampener and engages the groove of the inner housing. An outer portion of the top dampener engages the top stepped shoulder of the outer housing. The bottom coupling engages the bottom stepped shoulders of the inner and outer housings.

Abstract: A directional microphone intended for use in a computer visual display monitor, and methods for construction of same. The integral directional microphone assembly comprises a cardioid electret microphone capsule retained therein by acoustically transparent foam. The microphone housing is mounted internally within a display monitor housing facing the user and adjacent to the top surface of the monitor housing. The microphone housing comprises a frontal opening and a plurality of nonfrontally facing openings which together maximally preserve sound pressure gradient applied to the microphone capsule, resulting in a hypercardioid spatial response.

Abstract: A pickup amplifier system for a public address system including an amplifier, an amplifier box and a speaker simulator microphone wired between amplifier and amplifier box.The amplifier system is characterized by the following features:the speaker simulator is arranged in the area of the amplifier box, close by or on its front face; and,an acoustic pickup is arranged directly before on the front face of the amplifier box.

Abstract: A wireless conference microphone has a conical base housing with a downward-mounted microphone. A single circuit board is mounted above the microphone, and its circuits transmit the microphone output using infrared diodes on the circuit board, positioned around the periphery of the housing. A battery pack is mounted above the circuit board, and a decorative octagonal cover is provided over the battery pack. A three-position power switch selects either of two transmitting frequencies, and a multi-functional connector selectively interfaces the microphone with external devices, including a mute switch, audio level inputs and outputs, and slave modulators. The microphone can be connected to a like microphone for master-slave operation for use in larger conference rooms.

Abstract: A high resolution computer visual display monitor employing a cathode ray tube (CRT) having a vertical aperture grill intended for personal computer systems and integrating a high quality stereophonic speaker system and a directional microphone, and methods for construction of same. The aperture grill has a natural frequency centered within the musical scale. The stereo speaker system comprises a ported speaker enclosure within which are mounted two conventional cone speaker assemblies. A stereo audio amplifier and control unit for controlling the audio signals delivered to the speakers is mounted within the speaker enclosure. The speaker enclosure is internally mounted within the monitor with a minimum number of attachment members incorporating vibration isolation material to remove vibration components near the natural frequency of the aperture grill.

Abstract: An acoustic antenna for computer workstation, used for video conferencing that comprises a plurality of microphones connected to a summator circuit. The microphones are distributed in a layout so as to form a substantially straight line and are each spaced with respect to a reference microphone placed in the vicinity of the vertical axis of symmetry of the screen of the workstation according to a specified law. The layout exhibits a substantially cylindrical directivity pattern whose axis of revolution is formed by the straight line.

Abstract: This invention involves the integration of piezoelectric speaker panels and microphones into a personal computer with a sound card to form a novel multi-media computer. In addition noise cancellation electronics and algorithms are also applied to enhance performance of the voice recognition system.

Abstract: A sound amplification system includes an amplifier and a waterproof microphone. In an exemplary embodiment the microphone includes a transducer within a cavity covered by a resilient waterproof membrane. The system can monitor either the complete frequency range of the microphone or only one or more selected frequency ranges. The system can include one or more noise emitting lures that produce sound in a frequency range corresponding to the one or more selected frequency ranges. The invention also includes a method of waterproofing a miniature microphone.

Abstract: An acoustic sensing means such as a microphone or a thin-film sensor is located in a flowing medium. To prevent the sensing of flow generated noise, the sensing means is separated from the flowing medium by at least three stages of shielding. In a preferred embodiment, the sensing means is located within a foam shield which is located in a frame covered by a fabric shield and which is, in turn, located in a second frame covered by a second fabric shield. A spandex fabric is suitable for use in the present invention.

Abstract: A universal adapter kit for a two-way radio having a microphone jack. The adapter kit includes a universal keying adapter including a radio plug for attachment to the microphone jack of the standard two-way radio. The adapter kit further includes a microphone connected to the keying adapter, wherein the microphone is adapted to be selectively secured to a support structure, and a keying switch connected to the keying adapter. The keying adapter includes circuitry permitting an individual to use the microphone and the keying switch to transmit message over a wide variety of two-way radios without modifying the radio.

Abstract: A sound capturing method and device for use in making recordings having improved three-dimensional imagery during playback. Vibration information is detected from a body portion through the use of a crystal microphone for generating a first signal corresponding to a vibrational frequency of the body portion in response to a received sound wave. Direct sound information is detected from the body portion through the use of a condenser microphone affixed thereto at a second location for generating a second signal corresponding to a frequency of the received sound wave. The first and second locations are in proximity to one another such that a sound wave will reach each location at substantially the same time. Alternatively, the signals received at either location may be processed or time-delayed such that sound waves are recorded from each location at substantially the same time.

Abstract: A microphone boom mounting device has two portions, a track portion and a truck portion which moves along the track. The truck portion has a boom mount suitable for mounting a microphone boom. The movable microphone boom mounting device is mounted above a television or a motion picture production stage in a catwalk located above the stage. The track portion is formed in a "T" shape, and the truck portion has wheels which engage the top and bottom surfaces of the top part of the "T" section of the track. By moving the truck along the track, a microphone boom attached to the boom mount on the truck portion can be moved from side to side above the stage, such that a single microphone mount is all that is required to follow the actors on the stage in different sets on the stage and ensure a high quality sound recording.