104 results about "Dynamic noise" patented technology

The invention provides a Hidden Markov Model (132) based automated speech recognition system (100) that dynamically adapts to changing background noise by detecting long pauses in speech, and for each pause processing background noise during the pause to extract a feature vector that characterizes the background noise, identifying a Gaussian mixture component of noise states that most closely matches the extracted feature vector, and updating the mean of the identified Gaussian mixture component so that it more closely matches the extracted feature vector, and consequently more closely matches the current noise environment. Alternatively, the process is also applied to refine the Gaussian mixtures associated with other emitting states of the Hidden Markov Model.

Provided are an apparatus and method for speech segment detection, and a system for speech recognition. The apparatus is equipped with a sound receiver and an image receiver and includes: a lip motion signal detector for detecting a motion region from image frames output from the image receiver, applying lip motion image feature information to the detected motion region, and detecting a lip motion signal; and a speech segment detector for detecting a speech segment using sound frames output from the sound receiver and the lip motion signal detected from the lip motion signal detector. Since lip motion image information is checked in a speech segment detection process, it is possible to prevent dynamic noise from being misrecognized as speech.

One embodiment of the present invention provides a system that cancels fan noise in a computer system. During operation, the system obtains a fan noise signal using a microphone. Next, the system generates a spectral pattern based on the obtained fan noise signal. The system then uses the spectral pattern to identify a corresponding cancellation spectrum in an anti-spectra library. Next, the system generates a noise-canceling signal using the cancellation spectrum. Note that the amount of computation required to cancel fan noise is reduced because generating the noise-canceling signal using the anti-spectra library requires less computation than generating the noise-canceling signal using dynamic noise-cancellation techniques.

The invention discloses a multi-system dynamic PPP resolving method based on robust self-adaption Kalman smoothing. The method includes the steps that receiving machine outline coordinates and receiving machine clock bias of all systems are solved through selecting-weight-iteration pseudo-range single-point positioning, and accordingly all positioning error correction values are calculated according to an error correction model in combination with the satellite precise ephemeris and satellite precise clock bias; strict data quality control is conducted on observation data. Due to the fact that dynamic PPP accuracy is easily affected by undetected small cycle slips or the gross error and the like, an observation equation weight matrix is adjusted according to the observation value residual vectors, and the undetected small cycle slips or the gross error and other influence factors are removed; self-adaption factors are determined according to the state predictive information, and thus the influence on parameter estimation of the predictive information is controlled. By means of the method, when multi-system dynamic PPP is conducted through a single receiving machine, the feature that the number of multi-system satellites is increased greatly, on the basis that the stability of the satellite structure is guaranteed, the influence of the gross error is weaken effectively, the dynamic noise abnormity in dynamic positioning is improved, and finally the high-precision and high-stability multi-system dynamic PPP result is achieved.

A method and apparatus for processing imager pixel signals to reduce noise. The processing includes receiving a target pixel signal, receiving at least one neighboring pixel signal, formulating a dynamic noise signal based at least in part on a value of the target pixel signal, and controlling a noise reduction operation using the dynamic noise signal.

A speech enhancement system improves the speech quality and intelligibility of a speech signal. The system includes a time-to-frequency converter that converts segments of a speech signal into frequency bands. A signal detector measures the signal power of the frequency bands of each speech segment. A background noise estimator measures a background noise detected in the speech signal. A dynamic noise reduction controller dynamically models the background noise in the speech signal. The speech enhancement renders a speech signal perceptually pleasing to a listener by dynamically attenuating a portion of the noise that occurs in a portion of the spectrum of the speech signal.

An apparatus and a concomitant method for speech recognition. In one embodiment, the present method is referred to as a “Dynamic Noise Compensation” (DNC) method where the method estimates the models for noisy speech using models for clean speech and a noise model. Specifically, the model for the noisy speech is estimated by interpolation between the clean speech model and the noise model. This approach reduces computational cycles and does not require large memory capacity.

The invention discloses an adaptive extended kalman filtering-based road slope estimation method which comprises the following steps: acquiring vehicle state data through a data acquisition device, and calculating model parameters according to the vehicle state data and fixed parameters of a vehicle; then building an extended kalman filtering estimation model based on a relation model between a slope and the vehicle state data; finally, improving the kalman filtering estimation model into an adaptive extended kalman filtering algorithm model. According to the method provided by the invention, by the use of an adaptive extended kalman filtering algorithm capable of realizing rapid convergence and real-time estimation, the road slope can be dynamically estimated in real time according to the vehicle driving state data, so that real-time road slope information can be supplied to a driver, and important basis can be supplied for automatic driving assistant decision making, green driving and automatic transmission gear shifting control, to realize safe, economical and comfortable driving; the slope estimation precision under uncertain dynamic noise influence is improved, and the application range is extended.

The invention discloses a dynamic comparator with high speed and low kick noise, which belongs to the field of analog integrated circuits. Its structure includes: pre-amplification stage, current compensation branch for suppressing kickback noise, positive feedback regeneration stage composed of N-channel transistor and P-channel transistor cross-coupling unit, current between pre-amplification stage and positive feedback regeneration stage A control unit, a reset control unit, an offset calibration unit, and an inverter output driver stage. The two current compensation branches that suppress the kickback noise compensate the current attenuation of the main channel to ensure a constant working current of the input pair tube, thereby suppressing the influence of the kickback noise on the input signal, thereby increasing the size of the input pair tube and reducing offset voltage, increasing the response speed. Compared with the traditional comparator, the invention satisfies the requirement of high speed and low power consumption, and exhibits excellent kickback noise suppression ability.

A systems and a method for a DMT-based DSL modem to detect time-varying noise dynamically during transmission and adapt to its rapid changes promptly by increasing or reducing data rate while maintaining the transmission and utilizing maximum channel capacity. A DMT-based modem reserves a first set of sub-channels to detect and measure the time-varying noise. The modem further provides reliable communications for control messages through a second set of sub-channels. The control messages are used to adjust communication to adapt to the new noise conditions over all sub-channels.

This invention discloses a method for precessing analog image signals and its circuit of CMOS image sensor, which divides a pixel matrix into two symmetric odd and even arrays and sends related double sample values of each pixel signal to related two symmetric odd and even aray pixel simmulation image signal process circuits composed of a primary switch capacitance difference operation amplifying circuit only orderly at positive and negative half cycles of a line clock to carry out subtraction operation to eliminate dynamic noise and fixed mode noise of the circuit generated by the difference of sample circuits in different ranks and their drive circuit devices and realize control of color gain, exposal gain and dark background not influenced by the exposal background contol.

Methods and systems are provided for using localized dynamic element matching (DEM) and/or dynamic noise scaling (DNS) in digital-to-analog converters (DACs). Adaptive (localized) DEM may be applied in a DAC, by selecting one or more of a plurality DAC elements in the DAC, forcing the selected one or more of the plurality of DAC elements not to switch during digital-to-analog conversions, and scrambling remaining one or more of plurality of DAC elements when generating an output of the DAC. The adaptive DEM may be applied when the DAC input is backed off from full-scale. DNS may be applied in a DAC, by adaptively selecting one or more of a plurality DAC elements in the DAC and switching off the selected one or more of the plurality DAC elements such that the selected one or more of the plurality DAC elements do not contribute to generating an output of the DAC.

A dynamic noise filter is disclosed, which includes a noise estimation circuit, a TNR filtering circuit, a SNR filtering circuit, a blending circuit and a motion estimation circuit. By performing noise estimation for each image, the invention dynamically adjusts the strengths of the TNR filter and the SNR filter as well as a blending ratio between the outputs of the TNR filter and the SNR filter, thereby obtaining the best image quality.

The invention relates to the field of information processing technology and sensor signal processing, and particularly relates to a time-domain self-adaptive automatic speech detection method based on dynamic noise estimation. According to the invention, based on time-domain short time energy of sound and frequency-domain short time energy variation in a certain range, speech detection is carried out; and finally, the optimal result is selected according to dynamically estimated magnitude of background noise energy. The accuracy of speech recognition is greatly improved. The adaptability of speech recognition to environmental change is improved.

Disclosed are a multi-microphone noise reduction method, an apparatus and a terminal device. The method includes: performing harmonic detection on a primary microphone signal to obtain frequency bin VAD flag information; controlling, according to the frequency bin VAD flag information, a Kalman filter to filter out a target speech signal from a secondary microphone signal, to obtain a secondary microphone noise signal; mapping the secondary microphone noise signal to the primary microphone signal through dynamic noise spectrum mapping, to obtain a primary microphone noise spectrum of the primary microphone signal; and calculating a noise reduction gain for the primary microphone signal according to at least the primary microphone noise spectrum of the primary microphone signal, and outputting a noise-reduced primary speech signal. The method has good robustness to location changes, various noises and application scenarios, and can be applied to both the handheld and hands-free modes.

The invention discloses an acoustic control method of an active structure of a sealed cavity. The method comprises the following steps that firstly, the acoustic control problem of the structure of the sealed cavity is resolved; secondly, a local control problem solution scheme is provided; thirdly, coordination between controller bodies is carried out. According to the method, the bodies can be conveniently added or removed, and the rest of a system do not need to be redesigned, and it is indicated that a surface system has high expandability. In addition, the method has the self-governing performance, flexibility and sociality, and dynamic noise in the sealed cavity can be effectively treated. In other words, the method has the advantages of being capable of meeting intelligence, strong robustness and expandability needed by large-scale engineering application and the like.

The invention discloses a refrigerator dynamic noise reduction control method. According to the method, a human body infrared sensor detects whether a person exists around a refrigerator or not, and asignal is transmitted to a controller; a noise sensor collects the noise value around the refrigerator, and the signal is transmitted to a controller; the controller has three compressor parameters,three condensation fan parameters and three timer parameters, according to the environment noise level and the human body infrared signal, whether the running rotating speed of a compressor and a condensation fan is adjusted or not is analyzed, and when a user is not nearby the refrigerator, a control program analyzes and determines the running rotating speed of the compressor and the condensationfan. The human body infrared sensor is arranged to induce whether the person is nearby the refrigerator or not, through the noise sensor, the environment noise around the refrigerator is collected, through the controller, according to the signals of the human body infrared sensor and the noise sensor, running power of the compressor and the condensation fan of the refrigerator is controlled, dynamic noise reduction of the refrigerator is achieved, and the user experience is improved.

A pulsed ion multifunctional detector used for both high performance liquid chromatograph and ion chromatograph, and experiment chromatograms attached also show that the detector has excellent multipurpose function in liquid chromatograph. The casing of the instrument is provided with a sample solution inlet, a sample solution outlet, a power supply socket, a liquid crystal display, an operation keyboard and a detection signal output interface. In the casing is provided a detection electromechanical member, which includes a central controller, a detection cell, a preposed subtracting module, a polarity transformation module, a noise processing module and an output amplifier module. The pulsed ion multifunctional detector can sensitively and accurately measure ion current of sample ionized directly in the detection cell, and subtract baseline background generated by various mobile phases and automatically eliminate dynamic noise and drift of the instrument.

The invention provides a self-biasing circuit. The self-biasing circuit comprises a biasing unit suitable for generating a bias voltage and inputting the bias voltage to a differential amplifier circuit so as to keep inputting a constant current source to the differential amplifier circuit; a copying unit circuit suitable for copying a bias current source as same as that in a tail current tube in a delay unit and generating an excitation signal which is output to the differential amplifier circuit; and the differential amplifier circuit suitable for outputting an adjustable grid voltage of the tail current tube of the delay unit based on a control voltage of an annular voltage-controlled oscillator and the excitation signal in the presence of the constant current source. Through the biasing circuit, the output swing of the delay unit is ensured to change along with the change of a control voltage, so that the current-voltage characteristic of a symmetrical load in the delay unit is kept, and elimination of the one-order component of dynamic noise is facilitated. At the same time, as the bias voltage of the tail current tube in the delay unit is adjusted continuously, adoption of a common-source and common-grid structure not only can be prevented from suppressing static noise, but the influence from finite output impedance also can be counteracted.