507 results about "Noise threshold" patented technology

A method of discriminating noise and voice energy in a communication signal. A signal is measured in a plurality of block periods, which are sampled to obtain a measurement of the block energy value for the signal. The blocks are compared to a noise threshold and to a voice threshold to discriminate between noise and voice. The thresholds for noise and voice are periodically updated based on the minimum and maximum energy levels measured for block energies. In a preferred embodiment, the voice energy threshold and noise energy threshold values are updated according to a formula where the revised thresholds are based upon a factor of the minimum and maximum energy levels of the current block and the most recent past block and the average energy of the previous blocks. Updating of threshold levels allows for more accurate estimation of noise and voice during changes in either noise, voice or both to avoid missclassification of noise and / or voice.

An audio system (100) is provided with improved adaptive filter (206) to automatically adjust signal gain depending on the ambient noise level. The original music signal passes through a normalized adaptive filter (206), and is subtracted from the ambient room signal detected by a microphone (120), resulting in an error signal that is an estimate of the ambient noise. The error signal is used to update a set of adaptation coefficients so that the normalized adaptive filter more accurately simulates the room transfer function, resulting in an better estimate of the ambient noise. The audio system (100) is calibrated automatically upon initial use to determine adaptation coefficients and noise threshold level to prevent runaway gain. System parameters are adjusted using a controller (124) with a user-friendly interface (400).

A system, method and wireless earpieces for managing power utilized by a pair of wireless earpieces. Ambient light conditions and noise levels in an environment of the pair of wireless earpieces are determined. The low power settings are activated for the pair of wireless earpieces in response to determining the ambient light conditions are below a light threshold or the noise levels are below a noise threshold; signal activity is below an activity threshold.

A method and apparatus for dynamically adjusting receiver sensitivity over an existing phone line home network is disclosed. The method includes what is referred to Continuous Carrier Detect (CCD) adaptation process implemented by a state machine to quickly adapt to the on the fly wire DC offset in a matter of a few milliseconds for achieving optimal receiver sensitivity. According to one embodiment, a noise threshold level is dynamically generated for detecting noises in incoming data stream from the existing phone line home network.

The invention provides a baseline updating method. The baseline updating method includes: detecting a first frame capacitance value; setting a baseline according to the first frame capacitance value; detecting a current capacitance value of a touch screen, and calculating a difference value between the capacitance value and the baseline; when the difference value between the capacitance value and the baseline is smaller than a negative noise threshold, starting a first timer for timing; if the difference values within a first time range are smaller than the negative noise threshold, updating the baseline according to the capacitance value to activate an extreme value recovery function of the baseline; judging whether the touch screen is touched or not according to the difference value between the current capacitance value and the updated baseline; and if judgment shows that the touch screen is touched, deactivating the extreme value recovery function of the baseline to enable the baseline not to be updated when the difference value between the current capacitance value and the updated baseline is smaller than the negative noise threshold again. By the aid of the baseline updating method in the embodiment, the touch screen is applicable to various operating environments while the operating speed of the touch screen is unaffected, and a certain waterproof effect can be achieved.

An automatic peak selection method for multidimensional data that selects peaks from very noisy data such as two-dimensional liquid chromatography-mass spectrometry (LC-MS) data is described. Such data are characterized by non-normally distributed noise that varies in different dimensions. The method computes local noise thresholds for each one-dimensional component of the data. Each point has a local noise threshold applied to it for each dimension of the data set, and a point is selected as a candidate peak only if its value exceeds all of the applied local noise thresholds. Contiguous candidate peaks are clustered into actual peaks. The method is preferably implemented as part of a high-throughput platform for analyzing complex biological mixtures.

A method is disclosed for determining estimates of the perceived noise masking level of audio signals as a function of frequency. By developing a randomness metric related to the euclidian distance between (i) actual frequency components amplitude and phase for each block of sampled values of the signal and (ii) predicted values for these components based on values in prior blocks, it is possible to form a tonality index which provides more detailed information useful in forming the noise masking function. Application of these techniques is illustrated in a coding and decoding context for audio recording or transmission. The noise spectrum is shaped based on a noise threshold and a tonality measure for each critical frequency-band (bark).

Provided are a touch sensor chip, a touch sensing apparatus including the same, and a method of controlling noise of a touch panel. The touch sensing apparatus includes: an electronic device which is driven by a clock signal; a touch panel which is placed adjacent to the electronic device and receives a touch signal; and a touch sensor chip which transmits a driving signal to the touch panel and hops a frequency of the driving signal by a hopping interval if a noise level at the frequency of the driving signal is equal to or higher than a noise threshold, wherein the hopping interval is set based on an exciting frequency of the touch sensor chip.

A method for determining the button state of a capacitive sensing screen determines the state of a button according to the capacitance value of the button, wherein if the capacitance value is greater than a touch threshold, the button is in a pushed-down state; if the capacitance value is less than a noise threshold, the button is in a non-pushed-down state; and the touch threshold is greater than or equal to the noise threshold. Each threshold comprises a baseline value and a deviation value, wherein the baseline value is based on the capacitance value acquired in advance of the button, and the deviation value is the maximum expected value of the capacitance before the button is pushed down. The baseline values are changed before each judgment, so influences of environmental factors can be incorporated into the touch threshold and the noise threshold to improve the accuracy of the judgment and the detection of the state of the button. In an optical embodiment, the baseline values areset to be the average value of a plurality of the latest capacitance values of the button, and the number of the samples for working out the average value is determined according to the latest measured capacitance of the button.

A method, system and computer-readable medium of filtering noise pixels and other extraneous data, including saturated fat tissue and air data in image data is provided. Examples of image data may include but are not limited to magnetic resonance imaging data and computed tomography data. The method includes receiving pixel count for each signal intensity value of the image data; determining a signal intensity value, Ipeak, corresponding to a pixel count of a greatest number of pixels, Npeak; setting a noise threshold at a signal intensity value, Inoise, corresponding to a pixel count, NI, such that NI, is determined based on Npeak; and filtering from the image data one or more pixels with signal intensity values below the noise threshold. NI, may be determined such that NI=Npeak / 3 or close to Npeak / 3.

A telephone includes a transmit channel and a receive channel, each including a bank of sub-band filters having a VAD coupled one to each sub-band filter. Each VAD measures the spectral energy in a sub-band, compares the spectral energy to a first threshold, and produces an output signal representative of whether or not the first threshold is exceeded. The voice activity detector also includes a threshold circuit for calculating a dynamically adjustable noise threshold based upon averaged measured spectral energy. A wide band or system VAD monitors echo canceling circuitry to detect voice activity and double talk. A dynamic balance control circuit maintains the transmit and receive channels in a predetermined energy ratio during double talk.

Adaptive sampling of pixels is disclosed. In some embodiments, an initial rendering of a scene that determines texture at each portion of the scene is generated, and a ray traced rendering of the scene is generated by tracing an initial sample of rays. The following steps are iterated until all portions of the ray traced rendering satisfy a noise threshold: subtract the initial rendering of the scene from the ray traced rendering of the scene to determine a measure of noise at each portion of the ray traced rendering and trace another sample of rays in the ray traced rendering for each portion of the ray traced rendering that does not satisfy the noise threshold. The completed ray traced rendering is outputted. Different portions of the completed ray traced rendering are sampled with different numbers of samples of rays.

A spectrum sensing method for cognitive radio wherein spectrum holes are detected in a wireless environment having spectrum scarcity. First, a cognitive radio user (CR) determines the power spectral density (PSD) of a wideband signal and detects subbands within the wideband using wavelet transforms (WT). WT coefficients are calculated by convolving the PSD with first derivatives of wavelet smoothing functions. The extrema of the WT coefficients demark frequency subband edges. Detecting subband edges becomes more robust against noise by median filtering the PSD before calculating WT coefficients, summing over WT coefficients with different scale factors, and suppressing WT coefficients below a noise threshold. After identifying subbands, the CR determines subband availability by measuring the subband power and signaling the power to a fusion center receiving power measurements from multiple cooperating CRs, and final decisions are based on data and decision fusion.

A touch detection method for a touch panel. The touch panel has a plurality of sensing nodes. Each sensing node has a baseline value. Each sensing node is sensed to obtain a scanned value. A touch event is detected according to a comparison with a finger-on threshold. When there is no touch event, the method detects whether or not an abnormal object has entered the sensing node. When entered, the method judges whether a difference count between the scanned value and baseline value is larger than a calibration level. When the difference count is larger, then the scanned value is used to update the baseline value. When no abnormal object, then the method judges whether the difference count is larger than a noise threshold. When the difference count is larger, then the scanned value is used to update the baseline value. The calibration level is smaller than finger-on threshold.

The present invention discloses a noise filtering method for a touch control display device. The noise filter method includes retrieving a plurality of touch signals, wherein the plurality of touch signals correspond to a plurality of touch points of the touch control display device, selecting a plurality of environmental sensing signals from the plurality of the touch signals according to a touch threshold value, calculating a peak-to-peak value of the plurality of the environmental sensing signals, comparing the peak-to-peak value with a noise threshold value to generate a comparison result, and determining a filtering coefficient according to the comparison result in order to perform a noise filtering procedure accordingly.

The utility model discloses a channel evaluation method and a device used for solving the problems in prior art of too complicated channel evaluation, big channel evaluation value error and the incapability of acquiring the maximum time delay and the root mean square time delay; and that the channel evaluation method only halts in the theory field and can not be applied in practice. The utility model comprises the steps: the channel evaluation value in the frequency domain is acquired through the pilot signal and the pilot symbol; the channel evaluation value in the frequency domain is transformed to the channel evaluation value in the time domain through the inverse Fourier transform; the noise threshold is settled based on the channel evaluation value in the time domain and the corresponding time delay value of the noise threshold is considered as the maximum time delay based on the negative exponential distribution characteristic of the multi-path power spectrum; the root mean square time delay is acquired based on the negative exponential distribution characteristic of the multi-path power spectrum and the noise threshold and the maximum time delay; and the channel evaluation value of the pilot sequence is acquired based on the maximum time delay and the root mean square time delay. The utility model can be used for evaluating the channel of the pilot frequency sequence.

A method and system applicable within a mobile transmission system for adaptively allocating a downlink data rate to an access terminal to compensate for channel fading. In accordance with the method of the present invention a downlink data rate selected in accordance with a determined signal-to-noise level, wherein the downlink data rate is associated with a specified signal-to-noise threshold to achieve a specified packet error rate. Next, a packet is transmitted to an access terminal at the selected downlink data rate. In response to successfully decoding the packet at the access terminal, the signal-to-noise threshold specified for the selected downlink data rate is decreased such that subsequent data rate selections are adaptively maximized. Responsive to a packet decoding error, the signal-to-noise threshold is abruptly increased to maintain the specified packet error rate.

A method and system applicable within a mobile transmission system for adaptively allocating a downlink data rate to an access terminal to compensate for channel fading. In accordance with the method of the present invention a downlink data rate is selected in accordance with a determined signal-to-noise level and an effective throughput, wherein the downlink data rate is associated with a specified signal-to-noise threshold to achieve a specified packet error rate. Next, a packet is transmitted to an access terminal at the selected downlink data rate. In response to successfully decoding the packet at the access terminal, the signal-to-noise threshold specified for the selected downlink data rate is decreased such that subsequent data rate selections are adaptively maximized. Responsive to a packet decoding error, the signal-to-noise threshold is abruptly increased to maintain the specified packet error rate.

The invention provides a system and a method for testing a signal of a detector. The system comprises a detector signal processing module, a pulse information collection module and a control module, wherein the detector signal processing module is used for outputting a digital pulse signal according to a comparative result of an analog signal output by the detector and a reference level threshold; the pulse information collection module is connected with an output end of the detector signal processing module and used for connecting the digital pulse signal; and the control module is connected with the detector signal processing module and the pulse information collection module respectively and used for determining the reference level threshold and testing a peak value and / or a noise threshold of an analog signal output by the detector according to a collection result of the digital pulse signal. The system is simple in structure, small in design difficulty and low in cost.

Embodiments of the present invention are directed to efficient video processing methods and systems for computationally efficient denoising, sharpening, contrast enhancement, deblurring, and other spatial and temporal processing of a stream of video frames. Embodiments of the present invention separate statistics-related calculations, including estimation of pixel-value-associated variances, standard deviations, noise thresholds, and signal-contrast thresholds, carried out on only a small percentage of video frames selected at a fixed or variable interval from the video stream, from various spatial and temporal processing steps carried out on each frame of the video stream. In certain embodiments of the present invention, the statistics-related calculations are carried out by the general processor or processors of a computer system, while the frame-by-frame spatial and temporal processing is carried out by one or more specialized graphics processors within the computer system.

A plurality of Goertzel filters whose operating frequencies are distributed across the voice baseband are used to detect voice and control tones in a signal. Filters operating at frequencies of control tones and detecting that most of the signal energy occurs at those frequencies indicates presence of the control tones. At least three of the filters detecting that about 10% to 20% of the signal energy occurs at each of their operating frequencies indicate presence of voice. The total energy detected in the signal being below a noise threshold indicates presence of noise or silence.

The invention belongs to the technical field of the digital communication and particularly relates to an automatic gain control method for an orthogonal frequency division multiplexing system. The method of the invention comprises the following steps: setting a gain initial value of the AGC; measuring a signal average power of each frequency point; judging whether a power average value is less than a noise threshold, and if not, comparing the maximum value of the signal average powers with a target power value and taking the difference value of the maximum value and the target power value as an AGC adjustment increment; if the AGC adjustment increment exceeds an adjustment threshold, adjusting an AGC gain value; and completing the AGC process and outputting a received signal which is subjected to gain adjustment to carry out post-processing. The method of the invention can guarantee the signal power stabilized in an optimum range and reduce the quantization error of the post-processing.

The invention discloses an adjusting method and device for an air conditioner. The method comprises the steps that after the air conditioner enters a preset work mode, a sound source is detected through a sound source detecting device, and all detected sound source frequencies and corresponding real-time noise values are obtained; noise frequencies of air flow sounds and corresponding real-time noise values are extracted from the obtained sound source frequencies and the real-time noise values, and preset noise threshold values corresponding to the noise frequencies of the air flow sounds are determined; when the real-time noise values of the air flow sounds are smaller than or equal to the corresponding preset noise threshold values, whether the real-time noise values of the air flow sounds are larger than the corresponding standard noise values or not is judged; and when the real-time noise values of the air flow sounds are larger than the corresponding standard noise values, a stepping motor of the air conditioner is adjusted to adjust the air guide angle of an air guide plate. The noise in the running process of the air conditioner is lowered, and then the influence of the noise of the air conditioner on work and life of users is lowered.

The invention discloses a method for measuring and compensating the deficient image element in digital image outputted by image sensor, which includes following steps: at first, works out the difference of brightness between the current image element and the relative image elements in parallel and vertical directions; secondly, determines the efficient direction according to the absolute value of the two different values; works out the brightness average of relative image element in the direction, and the parameter Var; compares the Var and a preset noise threshold T; finally, compensates them according to the judging result. By using the invention, the memory and the control unit can be saved, and it can measure the deficiency image element which occurs after being sold and not recorded in the memory.

A method and apparatus for adaptively controlling the audio output (122) of a communication device (114) according to the noise characteristics of the receiver listening environment (119). An output volume for the communication device (114) is set by a user (e.g., listener 118). The communication device (114) can intermittently sample ambient noise (116) of its environment (119). A minimum signal to noise threshold can be established for audio output (122). A total adjustment for the audio output (122) is established based on the ambient noise (116), the user set output volume, and the minimum signal to noise threshold. The total adjustment is a product of a software volume adjustment (230) and a hardware gain adjustment (240). The software volume adjustment (230) and the hardware gain adjustment (240) is adaptively applied when the communication device (114) outputs audio (122).

The invention discloses an unmanned aerial vehicle identification method and system based on real-time signal feature analysis. The method comprises the steps of S10, preprocessing received original signals, thereby obtaining time continuous real-time signals; S20, carrying out signal feature parameter extraction, carrying out classification and identification and determining signal parameters; and S30, carrying out analysis and statistics on sorting results, thereby judging whether unmanned aerial vehicles exist in the current signals or not. The S20 comprises the process of carrying out noise base judgment on the received real-time signals, calculating initiation and termination frequencies, central frequencies and occupied bandwidths of the signals according to a noise threshold; addingtime labels to the signals; and acquiring frequency hopping signal features according to features comprising time, frequencies and bandwidths of the signals at each frequency point. According to themethod and the system, the signal analysis is carried out based on continuous time signals, through deep analysis of the signal features, relatively much information can be mined, and the intercept probability of unmanned aerial vehicle signals can be effectively improved.

Various embodiments of the present inventions are related to adaptive calibration of NPFIR filters in a data detector. For example, an apparatus for calibrating a noise predictive filter is disclosed, including a data detector operable to generate detected values for data sectors and having an embedded noise predictive finite impulse response filter. The apparatus also includes a comparator operable to determine whether a quality metric for a current one of the data sectors meets a noise threshold. The apparatus also includes a filter calibration circuit operable to adapt a number of filter coefficients for the noise predictive finite impulse response filter based on the detected values for the data sectors, and to omit the detected values for the current one of the data sectors from adaptation for one of the filter coefficients if the quality metric for the current one of the data sectors does not meet the noise threshold.

An image registrations includes determining a first binary descriptor of a first key point in a first image, determining a second binary descriptor of a second key point in a second image, determining a weighted Hamming distance between the first binary descriptor and the second binary descriptor, and registering the first key point with the second key point when the weighted Hamming distance is below a noise threshold. At least one element in the first or the second binary descriptor is a result of a comparison of a difference between intensities of at least two pixels of the first or the second image with a threshold. At least two weights of the weighted Hamming distance for comparing at least two elements of the first or the second binary descriptors are different.

A largest eigenvalue is determined among eigenvalues corresponding to a correlation matrix indicating correlations between a plurality of channels receiving incoming radar waves from an object that reflects a radar wave as a reference eigenvalue λ1. A ratio Rλi (=10 log 10(λi / λ1)) is calculated of each eigenvalue λ2 to λN to the reference eigenvalue λ1. Eigenvalues among the reference eigenvalue λ1 and the eigenvalues λ2 to λN of which the eigenvalue ratio Rλi is greater than a noise threshold TH are identified as eigenvalues in signal space. Eigenvalues of which the eigenvalue ratio Rλi is equal to the noise threshold TH or less are identified as eigenvalues in noise space. The number of eigenvalues identified as the eigenvalues in signal space is counted as the number of arrival signals.