120 results about "Transient noise" patented technology

Audio frames are classified as either speech, non-transient background noise, or transient noise events. Probabilities of speech or transient noise event, or other metrics may be calculated to indicate confidence in classification. Frames classified as speech or noise events are not used in updating models (e.g., spectral subtraction noise estimates, silence model, background energy estimates, signal-to-noise ratio) of non-transient background noise. Frame classification affects acceptance / rejection of recognition hypothesis. Classifications and other audio related information may be determined by circuitry in a headset, and sent (e.g., wirelessly) to a separate processor-based recognition device.

A switching DC-to-DC converter includes multiple power supply channels, coupled in parallel between a DC voltage source and ground, for converting the DC voltage source into multiple DC output voltages that are separate from each other. An oscillator outputs multiple oscillating signals to render each of the multiple power supply channels make at least one switching transition differently in the time domain from others of the multiple power supply channels, thereby improving transient noise. The multiple oscillating signals include two triangular wave signals with a phase difference of 180 degrees and two pulse wave signals with a-phase difference of 180 degrees. Rising edges of the two pulse wave signals occur simultaneously with either a peak or a valley of the two triangular wave signals, respectively.

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.

Switching voltage regulator embodiments are provided with hysteretic control to thereby switch between pulse-width modulation and pulse-frequency modulation operational modes. The switching is in response to different levels of an error voltage Verr in the feedback loop of voltage regulators. The hysteretic control is configured to provide a dc hysteretic response to changes in the error voltage Verr and also an ac hysteretic response to these changes. These two responses can be independently set to thereby enhance operational speed of the voltage regulators and also enhance immunity to transient noise signals that are generated by the mode switching. The voltage regulator embodiments facilitate instant return from the pulse-frequency modulation operational mode to the pulse-width modulation operational mode so that the stability of the feedback control of the regulator is enhanced. This feature is especially useful when the feedback loop is configured to include current-mode control as it minimizes the time duration in which the feedback loop operates in a voltage-mode control. The instant return insures that the feedback loop is immediately returned to the greater stability of the current-mode control.

A system improves the perceptual quality of a speech signal by dampening undesired repetitive transient noises. The system includes a repetitive transient noise detector adapted to detect repetitive transient noise in a received signal. The received signal may include a harmonic and a noise spectrum. The system further includes a repetitive transient noise attenuator that substantially removes or dampens repetitive transient noises from the received signal. The method of dampening the repetitive transient noises includes modeling characteristics of repetitive transient noises; detecting characteristics in the received signal that correspond to the modeled characteristics of the repetitive transient noises; and substantially removing components of the repetitive transient noises from the received signal that correspond to some or all of the modeled characteristics of the repetitive transient noises.

A system and a method for producing enhanced speech data associated with at least one speaker are provided. The process of producing the enhanced speech data comprises: receiving distant signal data from a distant acoustic sensor; receiving proximate signal data from a proximate acoustic sensor located closer to the speaker than the distant acoustic sensor; receiving optical data originating from an optical unit configured for optically detecting acoustic signals in an area of the speaker and outputting data associated with speech of the speaker; processing the distant and proximate signals data for producing a speech reference and a noise reference; operating an adaptive noise estimation module, which identifies stationary and / or transient noise signal components, by using the noise reference; and operating a post filtering module, which uses the optical data, speech reference and identified noise signal components for creating an enhanced speech data.

A method and apparatus for evaluating window regulators of the type having a reversible electric motor connected to a slide / carrier plate by means of cables. The apparatus comprises a first transducer such as a piezoelectric accelerometer or a laser for generating a first signal quantity related to periodic noise produced by the motor during operation thereof, a second transducer such as a piezoelectric accelerometer for producing a second signal quantity representing transient noise produced by irregularities in the slide / carrier plate assembly during travel of the carrier plate along the slide, and a processor for decoding the first and second waveforms and using data derived therefrom as a basis for identifying unacceptably noisy window regulator assemblies. The method comprises placing the window regulators on a test fixture, operating the window regulator with a simulated glass load, and generating and processing the first and second signal quantities as described above.