12 results about "Whitening filter" patented technology

A spatial audio processing system operable to enable audio signals to be spatially extracted from, or transmitted to, discrete locations within an acoustic space. Embodiments of the present disclosure enable an array of transducers being installed in an acoustic space to combine their signals via inverting physical and environmental models that are measured, learned, tracked, calculated, or estimated. The models may be combined with a whitening filter to establish a cooperative or non-cooperative information-bearing channel between the array and one or more discrete, targeted physical locations in the acoustic space by applying the inverted models with whitening filter to the received or transmitted acoustical signals. The spatial audio processing system may utilize a model of the combination of direct and indirect reflections in the acoustic space to receive or transmit acoustic information, regardless of ambient noise levels, reverberation, and positioning of physical interferers.

The present application relates to the technical field of noise processing, and discloses a noise whitening method, device, equipment and storage medium, the method comprises the following steps: constructing an error function based on an equalization signal and a training sequence; calculating based on the error function to obtain gradient information; updating the tap coefficient of the noise whitening filter based on the gradient information to obtain a target tap coefficient; whitening the colored noise based on the target tap coefficient. The present application updates the tap coefficient of the noise whitening filter by formulating the error function and calculating the gradient, solves the problem that when the channel equalization technology is used to overcome the bandwidth limitation, the equalization enhances the colored noise, leads to uneven noise power spectrum, and thus reduces the IM-DD transmission rate, realizes the whitening of the colored noise, makes the power spectrum flat, and thus significantly improves the performance of the IM-DD system and increases the communication capacity.

An electronic device includes a communication circuit including 2N reception antennas, and a communication processor including a covariance matrix generation circuit that generates a covariance matrix for the 2N reception antennas based on a measurement of a received signal, and a whitening filter matrix generation circuit that calculates a whitening filter for N reception antennas based on Cholesky decomposition. The covariance matrix includes a first sub-matrix, a second sub-matrix, a third sub-matrix, and a fourth sub-matrix, and the whitening filter matrix generation circuit calculates a whitening filter matrix for the 2N reception antennas based on characteristics of a first whitening filter matrix and the Cholesky decomposition for the first sub-matrix corresponding to a diagonal sub-matrix of the covariance matrix.

This invention relates to the field of microphone technology, specifically to a method and system for suppressing echo and howling using a combination of bone conduction and air conduction microphones, applied to a closed-loop audio device including a combination microphone, a loudspeaker, and a feedback path estimation filter. The method involves acquiring a bone conduction signal as a target sound reference through a bone conduction acquisition channel, and acquiring a microphone signal containing target sound components and echo feedback components through an air conduction acquisition channel. The feedback path estimation filter is used to estimate the feedback path of the loudspeaker signal, generating a feedback estimation signal which is subtracted from the microphone signal to obtain an error signal. The error signal is then soft-limited to obtain a soft-limiting error signal, which forms the updated loudspeaker signal. A pre-whitening filter is established based on the soft-limiting error signal to obtain a pre-whitened microphone signal, a pre-whitened loudspeaker signal, and a pre-whitening prediction error signal. A stability detection signal is generated based on the difference between the error signal and the soft-limiting error signal. In a stable state, a normalized minimum mean square branch is used for updating; in a howling-prone state, an affine projection branch is used for updating, to track feedback path changes and suppress echo and howling.

The application discloses a ship target detection method and device based on non-local information, and relates to the technical field of ship target detection. The method comprises the following steps: determining a to-be-detected area and a non-local area in which a target pixel is located according to a superpixel segmentation technology; performing similarity calculation on the target pixel in the to-be-detected area and pixels in the non-local area one by one, and determining a non-local area pixel corresponding to a minimum similarity value; determining a non-local information polarization covariance matrix through an inner product formula; determining a polarization whitening filter value of the target pixel and a target detection threshold value, and determining a ship pixel according to the polarization whitening filter value of the target pixel and the target detection threshold value. The method considers the spatial information around the pixel, can significantly overcome the interference of sea clutter under complex sea conditions, can better improve the signal-to-clutter ratio of the ship target, and ensures that the ship target can be accurately detected.

The invention discloses an anti-tank missile identification method based on improved orthogonal basis decomposition and autoregression model noise processing. The method comprises the following steps: S1, acquiring an original geomagnetic signal sequence containing target magnetic anomaly and background geomagnetic noise at a preset sampling rate by using a magnetic detection sensor; s2, performing autoregression AR modeling on background geomagnetic noise in the original geomagnetic signal sequence, constructing a whitening filter according to an AR model, and performing pre-whitening processing on the original geomagnetic signal sequence to obtain a whitened signal sequence; s3, correcting the standard orthogonal basis function group according to the transmission characteristics of the whitening filter to obtain a corrected standard orthogonal basis function group matched with the whitened target signal; and S4, inputting the whitened signal sequence into a corrected standard orthogonal basis decomposition unit, calculating a basis function coefficient corresponding to a corrected standard orthogonal basis function group, and calculating an energy function according to the basis function coefficient.

The invention discloses a power delay spectrum estimation method based on frequency domain noise whitening, which is applied to a power line communication system. According to the method, in order to solve the problems that power line channel frequency selective noise is high and a special silence period is lacked, the noise power spectral density is directly estimated from a received signal through frequency domain smoothing processing, a frequency domain whitening filter is designed according to the noise power spectral density to conduct whitening and normalization processing on channel response, the frequency selective noise is converted into flat noise, and the frequency selective noise is obtained. And a power delay spectrum with a substantially reduced noise floor is generated. On the basis, multipath components are accurately recognized through peak detection and parameter estimation, signals are reconstructed to separate and calculate signal and noise power, and finally high-precision signal-to-noise ratio estimation is achieved. According to the method, a silent period is not needed, frequency selective noise can be effectively resisted, and the accuracy of multipath parameter and signal-to-noise ratio estimation is remarkably improved.

A wireless communication device includes a transceiver configured to receive a wireless signal, and a processor configured to in a time-frequency domain, in which resources are allocated across subcarriers and symbols in a given time slot for data transmission, determine a first area and a second area within a resource element (RE) area including a plurality of REs, segment the second area into a plurality of segmentation areas, calculate a first adjustment whitening filter and a plurality of segmentation adjustment whitening filters to be respectively applied to the first area and the plurality of segmentation areas, and perform an interference whitening operation on the first area and the plurality of segmentation areas, based on the first adjustment whitening filter and the plurality of segmentation adjustment whitening filters, respectively.

The invention provides an electronic device and an operating method thereof. The electronic device includes a communication circuit and a communication processor, where the communication circuit includes 2N receiving antennas, and the communication processor includes a covariance matrix generation circuit and a whitening filter matrix generation circuit, the covariance matrix generation circuit generates a covariance matrix for the 2N receive antennas based on a measurement of a receive signal, and the whitening filter matrix generation circuit calculates a whitening filter for N receive antennas based on a Cholesky decomposition. The covariance matrix includes a first sub-matrix, a second sub-matrix, a third sub-matrix, and a fourth sub-matrix, and the whitening filter matrix generation circuit calculates a whitening filter matrix for the 2N reception antennas based on a first whitening filter matrix for the first sub-matrix and characteristics of a Cholesky decomposition, the first sub-matrix corresponds to a diagonal sub-matrix of the covariance matrix.

The present invention discloses an active and passive coordinated sensing fusion method for a radar communication dual-function system. The method includes: step 1 embedding a dedicated sensing symbol in a signal transmitted by a base station; step 2 solving a power allocation problem using an optimization problem; step 3 having a receiving access point receive a passive sensing signal and process direct path interference into white noise using a whitening filter; step 4 having the receiving access point determine whether a target is present using a generalized likelihood ratio test detector, and then the receiving access point and base station transmit the binary determination result and target detection probability to a fusion center; and step 5 having the fusion center vote and aggregate the received information to determine whether a target is present. The present invention can improve the accuracy and efficiency of target detection, positioning and acquisition of environmental information, and reconstruction, and has the potential to significantly improve the performance of wireless communication sensing networks.

Provided are a wireless communication apparatus and an operating method thereof, in which the wireless communication apparatus includes processing circuitry configured to calculate initial channel estimation values based on a reference pilot signal and a pilot signal, the pilot signal being received from a second wireless communication apparatus over a communication channel, the initial channel estimation values corresponding to the communication channel, calculate noise-whitened channel estimation values by applying a noise whitening filter to the initial channel estimation values, calculate channel-smoothed channel estimation values by applying a channel smoothing filter to the noise-whitened channel estimation values, and calculate final channel estimation values by inversely applying the channel smoothing filter and the noise whitening filter to the channel-smoothed channel estimation values.

This invention discloses a method for estimating the envelope spectrum of ship radiated noise based on spectral whitening, belonging to the field of underwater acoustic signal processing. The method first determines the main frequency band containing the modulation characteristics of the target signal through cyclic modulation spectrum analysis; then, it processes the background noise spectrum within the main frequency band using smoothing, and calculates a spectral shaping factor based on the median of the smoothed spectrum to construct a conjugate symmetric whitening filter; finally, it performs weighted shaping of the target signal spectrum in the frequency domain, and restores the whitened spectrum to the time domain for amplitude demodulation and power spectrum analysis. This invention effectively improves the signal-to-noise ratio (SNR) of broadband envelope spectrum estimation by introducing a spectral whitening mechanism, providing a reliable guarantee for accurately extracting physical characteristics such as the number and rotational speed of ship propellers. Experiments show that this method can improve the average SNR of the envelope spectrum by approximately 7 dB, demonstrating strong engineering practical value.