473 results about "Noise attenuation" patented technology

A voice enhancement logic improves the perceptual quality of a processed signal. The voice enhancement system includes a noise detector and a noise attenuator. The noise detector detects and models the noise associated with rain. The noise attenuator dampens or reduces the rain noise from a signal to improve the intelligibility of an unvoiced, a fully voiced, or a mixed voice segment.

A portable ventilator uses a Roots-type blower as a compressor to reduce both the size and power consumption of the ventilator. Various functional aspects of the ventilator are delegated to multiple subassemblies having dedicated controllers and software that interact with a ventilator processor to provide user interface functions, exhalation control and flow control servos, and monitoring of patient status. The ventilator overcomes noise problems through the use of a noise attenuating system comprising noise reducing pressure compensating orifices on the Roots blower housing and multiple noise reducing chambers. The ventilator is configured with a highly portable form factor, and may be used as a stand-alone device or as a docked device having a docking cradle with enhanced interface and monitoring capabilities.

A voice enhancement system is provided for improving the perceptual quality of a processed voice signal. The system improves the perceptual quality of a received voice signal by removing unwanted noise from a voice signal recorded by a microphone or from some other source. Specifically, the system removes sounds that occur within the environment of the signal source but which are unrelated to speech. The system is especially well adapted for removing transient road noises from speech signals recorded in moving vehicles. Transient road noises include common temporal and spectral characteristics that can be modeled. A transient road noise detector employs such models to detect the presence of transient road noises in a voice signal. If transient road noises are found to be present, a transient road noise attenuator is provided to remove them from the signal.

A noise attenuation baffle assembly for a duct, is provided. The baffle assembly includes a number of baffles arranged in a spaced apart relation to one another. Each baffle includes a first side and a second side. The baffle assembly further includes a first bracket coupled to the first side of each baffle of the number of baffles. The baffle assembly further includes a second bracket coupled to the second side of each baffle of the number of baffles. The first and the second bracket are configured to be coupled to the duct.

A method enables a gas turbine engine to be operated. The method comprises channeling exhaust gases from a core engine through an exhaust assembly and past at least one flow boundary surface, and selectively operating a noise suppression system extending from the at least one flow boundary surface to facilitate attenuating noise generated during engine operation.

An earpiece for real-time audio processing of ambient sound includes an ear bud that provides passive noise attenuation to the earpiece such that exterior ambient sound is substantially reduced within an ear of a wearer, an exterior microphone that receives ambient sound and converts the received ambient sound into analog electrical signals, and an analog-to-digital converter that converts the analog electrical signals into digital signals representative of the ambient sounds. The earpiece further includes a digital signal processor that performs a transformation operation on the digital signals according to instructions received from a mobile device, the transformation operation transforms the digital signals into modified digital signals, a digital-to-analog converter that converts the modified digital signals into modified analog electrical signals, and a speaker that outputs the modified analog electrical signals as audio waves.

The invention comprises a method and apparatus for reducing the noise generated by compressors, including Roots-type blowers. The invention has particular use for reducing noise generated by compressors used in mechanical ventilators, though the advantages thereof may be realized in many different applications. One embodiment of the invention comprises a noise-attenuating gas flow path for a compressor contained in a portable ventilator housing. In one embodiment, the gas flow path comprises a plurality of chambers interconnected by flow tubes. The flow path is folded so as to fit into the limited space of a portable ventilator housing. The dimensions of the chambers and the flow tubes are selected so that an impedance mismatch is created between the chambers and the flow tubes. In one embodiment of the invention, the flow path comprises one or more perforated tubes located in one or more of the chambers. The perforated tube has a port through which gas is accepted and at least one exterior tube through which gas exits. Impedance mismatches are created between the inlet chamber and the exterior tubes and between the exterior tubes and the chamber in which the perforated tube is located, which are useful in attenuating noise. One embodiment of the invention comprises a noise attenuating mounting system for a compressor. The mounting system comprises flexible mounts that cooperate to dampen vibrations generated by the compressor.

A noise canceler for use in a transceiver is disclosed. In an exemplary embodiment, an apparatus includes a split amplifier to output an amplified transmit signal, the split amplifier providing a first noise attenuation factor in a receive band. The apparatus also includes a transmit antenna to transmit the amplified transmit signal, the transmit antenna being isolated from a receive antenna by an antenna isolation factor that provides a second noise attenuation factor in the receive band. The apparatus also includes a noise canceler configured to subtract a detection signal from a received signal to obtain an adjusted received signal, wherein subtraction of the detection signal provides a third noise attenuation factor in the receive band, and wherein the first, second, and third noise attenuation factors combine to provide a selected amount of noise attenuation in the receive band.

An apparatus for attenuating noise emanating from a cabinet housing noise-generating equipment includes a frame including at least one support member configured to be mountable on the cabinet, proximate the noise-generating equipment, at least one noise attenuation device mounted to each support member proximate the noise-generating equipment, the at least one noise attenuation device comprising a sound input device for receiving a noise signal output from the noise-generating equipment, a processing device for determining characteristics of the noise signal and generating a cancellation signal which is identical to the noise signal but approximately 180 degrees out-of-phase with the noise signal, and a sound output device for outputting the cancellation signal proximate the noise-generating equipment, to attenuate the noise emanating from the cabinet; and a noise absorption member mounted on each support member, the noise absorption members define surfaces that form sides of airflow channels through the apparatus.

A method of acquiring and processing seismic data including: acquiring digitized seismic data associated with a plurality of moving receiver points using a plurality of seismic sensors; attenuating noise in the moving receiver point based digitized seismic data using digitized seismic data associated with a plurality of nearby receiver points; transforming noise attenuated moving receiver point based digitized seismic data into stationary receiver point based digitized seismic data; and recording noise attenuated and transformed digitized seismic data associated with stationary receiver points having an average spatial separation interval at least twice the average moving receiver point spatial separation interval. This method is particularly effective at attenuating coherent low frequency noise and correcting for the receiver motion effect in marine seismic data.

A system and method for reducing noise in an automotive heating, ventilation, and cooling system is described. A noise attenuation device using radial vanes upstream of a flow discontinuity, such as a bend in the ducting, and downstream of a blower fan is used to reduce noise.

An acoustic liner includes a first core that has a plurality of first core cells defined by a corresponding plurality of first core cell walls. The first core has a first core thickness. The acoustic liner also includes a second core that has a plurality of second core cells defined by a corresponding plurality of second core cell walls. The second core has a second core thickness, and the first core thickness and the second core thickness are unequal. The acoustic liner further includes a second fabric sheet coupled between the first core and the second core. Each of the plurality of second core cell walls generally is not coplanar with any of the plurality of first core cell walls.

A gaming machine in a gaming establishment enhances its game sounds by attenuating ambient noise in the establishment. The gaming machine includes a microphone, processing circuitry, and an audio speaker. The microphone detects ambient noise and generates a noise signal from the sensed ambient noise. The processing circuitry generates an anti-noise signal from the noise signal and adds the anti-noise signal to a game sound signal generated by the gaming machine to produce an output signal. The audio speaker is driven with the output signal.

A wall element has a noise attenuating characteristic and is suitable for use as an aircraft cabin interior panel element that is mounted directly on the aircraft fuselage structure. The wall element includes a rigid lightweight composite panel having a core arranged between two cover layers, and an outer layer arranged adjacent and spaced away from one of the cover layers. The core and the cover layers of the composite panel are air permeable in a direction through the thickness of the panel, while the outer layer is non-air-permeable and is relatively soft and flexible. The outer layer is connected to the composite panel preferably only along the perimeter edge thereof. The non-permeable outer layer faces the aircraft cabin space, while the permeable composite panel is mounted on the fuselage structure. With this structure, acoustic vibrations of the fuselage, to which the wall element is attached, are attenuated and do not result in substantial noise radiation from the outer layer into the cabin.

The invention discloses an optimized analytical method for noise control in a transformer station. The optimized analytical method comprises the following steps of: (1) collection of basic data; (2) establishment of a physical model; (3) calculation of the value of noise at a receiving point; (4) judgment of limit values; (5) optimization analysis; and (6) selection of an optimal scheme. By adopting the optimized analytical method, the geometric divergence of noise transmission and the influence of atmosphere, ground, buildings, green belts and the like on noise attenuation in transmission routes can be accurately taken into consideration, therefore the magnitude of noise at arbitrary point in a transformer station or the space surrounding the transformer station can be accurately predicted, a more quick and effective design reference is provided for noise control engineering in the transformer station, and the noise of the transformer station at the preliminary stage of design can becontrolled to the extent of minimum impact on the environment; at the same time, an optimal sound barrier design scheme for the noise control of the transformer station can be obtained, the noise control effect is improved, the environment-friendliness requirements are better satisfied, the construction cost is lowered, and the blindness during noise control is avoided. In addition, the inventionalso provides an optimized analytical system for noise control in the transformer station.

The method of noise attenuation comprises the steps of generating a noise canceling signal, sensing for an system condition, and ceasing the generation of the noise canceling based upon the system condition. This method is embodied in a system that includes an air induction body, a speaker in proximity to the air induction body, a sensor for sensing a system condition, and a control unit with a noise cancellation feature. The control unit is in communication with both the speaker and the sensor. Based upon the sensed system condition, the control unit may disable the noise cancellation feature.