2508 results about "Signal extraction" patented technology

A switching circuit for supplying current to a load has a switching element, an inductive element coupled to the switching element, and a load current extraction circuit responsive to current in the inductive element for producing a load current signal as a simulated current approximating current in the load.

A signal processing method and system combining smooth level wavelet pre-processing together with artificial neural networks all in the wavelet domain for signal denoising and extraction. Upon receiving a signal corrupted with noise, an n-level decomposition of the signal is performed using a discrete wavelet transform to produce a smooth component and a rough component for each decomposition level. The nth level smooth component is then inputted into a corresponding neural network pre-trained to filter out noise in that component by pattern recognition in the wavelet domain. Additional rough components, beginning at the highest level, may also be retained and inputted into corresponding neural networks pre-trained to filter out noise in those components also by pattern recognition in the wavelet domain. In any case, an inverse discrete wavelet transform is performed on the combined output from all the neural networks to recover a clean signal back in the time domain.

An image sensor assembly includes a solid-state image sensor, the sensor including a matrix of detector elements including respective first and second pluralities of the detector elements producing respective first and second signals and having different, respective first and second sensitivities. The sensor assembly includes a signal extraction circuit, including first and second amplifiers for amplifying the first and second signals, respectively, with different, respective first and second amplification gains responsive to the first and second sensitivities.

The invention discloses a method for testing the assembly performance of a rotor of an aircraft engine, which comprises the following steps of: firstly exciting and vibrating a rotor of an aircraft engine with a vibration exciter; obtaining a multiple carrier-coupled impulse response signal of the rotor of the aircraft engine with a vibrating sensor and signal-acquiring system software; analyzing the obtained multiple carrier-coupled impulse response signal of the rotor of the aircraft engine by means of dual-tree complex wavelet transform to obtain eight signal carrier-coupled impulse response signals of the rotor of the aircraft engine; and distilling the average assembly performance index of the obtained eight signal carrier-coupled impulse response signals of the rotor of the aircraft engine, wherein the assembly performance of the rotor of the aircraft engine is judged to be qualified if the obtained average assembly performance index is larger than or equal to 10, and the assembly performance of the rotor of the aircraft engine is judged not to be qualified if the obtained average assembly performance index is less than 10, so that the rotor needs to be repaired.

A switching circuit for supplying current to a load has a switching element, an inductive element coupled to the switching element, and a load current extraction circuit responsive to current in the inductive element for producing a load current signal as a simulated current approximating current in the load.

A system for providing an accurate interference value signal received over a channel and transmitted by an external transceiver. The system includes a first receiver section for receiving the signal, which has a desired signal component and an interference component. A signal extracting circuit extracts an estimate of the desired signal component from the received signal. A noise estimation circuit provides the accurate interference value based on the estimate of the desired signal component and the received signal. A look-up table transforms the accurate noise and / or interference value to a normalization factor. A carrier signal-to interference ratio circuit employs the normalization factor and the received signal to compute an accurate carrier signal-to-interference ratio estimate. Path-combining circuitry generates optimal path-combining weights based on the received signal and the normalization factor. In the illustrative embodiment, the system further includes a circuit for employing the accurate interference value to compute a carrier signal-to-interference ratio. An optimal path-combining circuit computes optimal path-combining weights for multiple signal paths comprising the signal using the accurate interference value and provides optimally combined signal paths in response thereto. A log-likelihood ratio circuit computes a log-likelihood value based on the carrier signal-to-interference ratio and the optimally combined signal paths. A decoder decodes the received signal using the log-likelihood value. An additional circuit generates a rate and / or power control message and transmits the rate and / or power control message to the external transceiver.

The invention discloses a radar radiation source recognition method based on a deep learning strategy and a multitask learning strategy and mainly aims to solve the problem that recognition accuracy is low in the prior art. The method comprises the implementation steps that 1, an original radar radiation source signal is subjected to data preprocessing; 2, envelope features, fuzzy function features, slice features, cyclic spectrum features and frequency spectrum features of the preprocessed radar radiation source signal are extracted, and values of the features are linearly transformed into [0,255] and saved as an image set; 3, a convolutional neural network (CNN) is designed, and the multitask learning strategy and a random inactivation strategy are introduced into the CNN; and 4, four feature training sets are used to train the CNN, then four trained CNN models are utilized to classify four feature test sets, and a radar radiation source recognition result is output. The method is high in recognition accuracy and can be applied to electronic intelligence reconnaissance, electronic support reconnaissance and radar threat warning systems.

The present invention provides an FMCW broadband life detection radar breathing and heartbeat signal extraction algorithm. Compared with the prior art, the algorithm has the advantages that breathing and heartbeat signals of multiple persons can be obtained simultaneously, the boundaries and energy of reconstructed breathing signals can be very well kept by using Coiflets wavelets compared with traditional frequency-domain filtering, especially processing conducted on short-time signals is obvious, higher harmonics of the breathing signals are filtered out by adopting a double-coefficient based LMS self-adaptive filtering algorithm, and the self-adaptive filtering algorithm does not need additional reference signals. Due to the fact that a degressive search step size coefficient is adopted in the algorithm, the heartbeat signals can be better retained while breathing signal harmonics are filtered out, the heartbeat signals can be rapidly converged by selecting the appropriate search step size coefficient and adopting the double-coefficient based LMS self-adaptive filtering algorithm, and smaller stable imbalance is kept in longer time, so that finally separated heartbeat signals are more accurate in frequency component within a long time.

The invention discloses a way to recover separated seismograms with reduced interference noise by processing vibroseis data recorded (or computer simulated) with multiple vibrators shaking simultaneously or nearly simultaneously (200). A preliminary estimate of the separated seismograms is used to obtain improved seismograms (201). The preliminary estimate is convolved with the vibrator signature and then used to update the seismogram. Primary criteria for performing the update include fitting the field data and satisfying typical criteria of noise-free seismograms (202). Alternative ways to update are disclosed, including signal extraction, modeled noise extraction, constrained optimization based separation, and penalized least-squares based separation. The method is particularly suited for removing noise caused by separating the combined record into separate records for each vibrator, and is advantageous where the number of sweeps is fewer than the number of vibrators (200).

A biometric identification apparatus and method using bio signals and an artificial neural network, are provided. The biometric identification apparatus includes: a periodic signal extraction unit which extracts one or more periodic signals from an input bio signal; a template calculation unit which calculates a template value using the extracted periodic signals; a template storage unit which stores a plurality of template values corresponding to a plurality of living bodies; and a reading unit which reads the template value that is most approximate to the template value calculated by the template calculation unit from the template storage unit. Accordingly, it is possible to identify a living body by taking into consideration all of the characteristics of bio signals detected from the living body.

There is described an image processing method and an image converting apparatus for performing the image processing for recording the medical image information. The apparatus includes an image converting section to convert the image in respect to the original image signals; an image feature extracting section to extract image features for every pixel included in the plurality of pixels in respect to the original image signals; a sharpness information obtaining section to obtain sharpness information from the image converting section; a sharpness calculating section to calculate correlation between the image features and the sharpness information; and a frequency processing section to compensate for a sharpness level of the image, based on the correlation calculated by the sharpness calculating section, so as to reduce a variation of the sharpness level before and after the image converting section converts the image in respect to the original image signals.

An audio communication device comprises an input connectable to a narrowband audio signal source. The input can receive a narrowband audio signal having a first bandwidth. An extraction unit is connected to the input and arranged to extract a plurality of narrowband parameters from the narrowband audio signal. An extrapolation unit is connected to receive the plurality of narrowband parameters and arranged to generate a plurality of wideband parameters from the plurality of narrowband parameters. The extrapolation unit comprises one or more adaptive neuro-fuzzy inference system modules. The device further comprises a synthesis unit connected to receive the plurality of wideband parameters and arranged to generate, using the wideband parameters, a synthesized wideband audio signal having a second bandwidth wider than the first bandwidth. And the device comprises an output connectable to an acoustic transducer arranged to output for humans perceptible acoustic signals, for providing said synthesized wideband audio signal to the acoustic transducer.

A signal processing method and system combining smooth level wavelet pre-processing together with artificial neural networks all in the wavelet domain for signal denoising and extraction. Upon receiving a signal corrupted with noise, an n-level decomposition of the signal is performed using a discrete wavelet transform to produce a smooth component and a rough component for each decomposition level. The nth level smooth component is then inputted into a corresponding neural network pre-trained to filter out noise in that component by pattern recognition in the wavelet domain. Additional rough components, beginning at the highest level, may also be retained and inputted into corresponding neural networks pre-trained to filter out noise in those components also by pattern recognition in the wavelet domain. In any case, an inverse discrete wavelet transform is performed on the combined output from all the neural networks to recover a clean signal back in the time domain.

A power series type predistorter for multi-frequency bands includes a linear transmission path PL provided with a delay element 5 and distortion generating paths PD1 and PD2 for a plurality of frequency bands in parallel; wherein each of the distortion generating paths PD1 and PD2 for a plurality of frequency bands includes variable band signal extractors 111 and 112 for extracting a signal in each frequency band from input signals and distortion generators 131a and 132a which is provided with the extracted signals and which generates at least one of the odd number distortion components of the signals and making it as an output from the distortion generating paths PD1 and PD2 for frequency bands; and wherein the frequency band controller 6 controls frequency bands of the variable band signal extractors 111 and 112.

A system and method for providing timing information to a wireless device in a position determination system is disclosed. A wireless device includes a reference signal receiver, a signal processor, a wireless communications transceiver and a GPS receiver. The wireless device is adapted to receive a reference signal, extract a snippet of the received reference signal, determine a time of reception for the snippet and transmit the snippet and time of reception to a position determination entity as part of a request for GPS aiding information. The position determination entity includes a timing source, a GPS memory for storing GPS satellite information, a reference signal memory, a communications interface, a signal processor and a control processor. The position determination entity is adapted to continually receive and store a reference signal along with an associated time of reception, and receive the snippet and timestamp transmitted from the wireless device. The position determination entity is further adapted to match the signal snippet to a portion of the stored reference signal, determine a time offset between the timestamp and the time of reception of the matched portion of the stored reference signal, prepare aiding information for the wireless device, synchronize the aiding information to the wireless device using the time offset, and transmit the synchronized aiding information to the wireless device. The wireless device is further adapted to receive the aiding information, including timing information to assist the wireless device in acquiring the GPS signals.

The invention discloses a cold atom beam interference gyro device, which comprises a cold atom beam system, a coherent atom beam operating system, and a gyro rotating signal extracting system. The cold atom beam system continuously emits | 1 > state cold atom beams as a matter wave source; the coherent atom beam operating system is composed of three gratings placed on the emitting path of | 1 > state cold atom beams in turn, and three phase modulators for modulating the phases of three gratings, respectively; | 1 > state cold atom beams orderly enter the three grating for splitting, reflecting and splitting again so as to obtain | 2 > energy state atom beam and | 1 > state cold atom beam interference signals; the | 2 > energy state atom beam interference signals are induced to produce fluorescent signals by the probing laser of the gyro rotating signal extracting system, a photoelectric detecting device detects the fluorescent signals and transmits the signals to a computer for processing to obtain gyro rotating angular-speed signals. With this device disclosed by the invention, high-precision gyro absolute rotating signals relative to inertial space and with high requirement on environment can be obtained.

The invention discloses a memristor based image identification system and method. The system comprises an image signal extracting module, a plurality of memristor based neural network modules, and an identification module, wherein an input end of the identification module is connected with an output end of each neural network module, and an input end of each neural network module is connected with an output end of the signal extracting module. The method includes the following steps that (1) a feature vector of a gray level image to be identified is acquired and input into the neural network modules; (2) each neural network module grades and identifies the feature vector according to an image model of each neural network module; (3) a difference value between a value of each neural network module and obtained standard values during training is calculated, and the classification of an image to be identified is judged according to the difference value. The memristor based image identification system has good expansibility, high integration density, and low power consumption; the method has low time complexity and high identification accuracy.

A voltage detection device detects an objective AC voltage arising on a detection object. The voltage detection device includes; a detecting electrode placed so as to be capacitively coupled with the detection object; a reference signal output section for outputting a reference signal; a detecting section outputting a detection signal changing its amplitude in accordance with both current values of a detection object current flowing according to the objective AC voltage and a reference current flowing according to the reference signal; and a signal extracting section for extracting a signal component of the objective AC voltage from an amplified detection signal and outputting the signal component as an output signal, the amplified detection signal being obtained through controlling a gain for amplifying the detection signal so as to make a signal component of the reference signal included in the detection signal have a predetermined value.

The invention discloses an ultrasonic phased array inspection oil-gas pipe circular weld defect automatic recognition method, in particular to an ultrasonic phased array inspection oil-gas pipe circular weld defect automatic recognition method for a support vector machine, which belongs to a pipe circular weld defect type recognition technology. The recognition method includes two parts of the construction of a support vector machine model and the automatic recognition of unknown defect types in circular weld. The construction steps of the support vector machine model include artificial defect signals extraction, wavelet decomposition promotion, feature extraction, feature optimization and the training of the support vector machine model. The automatic recognition steps of unknown defect types in circular weld include defect signals extraction, optimized feature calculation and automatic recognition based on the support vector machine. The invention combines a lifting wavelet transform with a fractal technology and has the advantages of high recognition accuracy and fast recognition speed. The automatic recognition of the defect types can be realized.

The invention provides a hardware Trojan horse detection method and a hardware Trojan horse detection system. The method includes the following steps: collecting a by-pass signal of a to-be-detected integrated circuit; extracting features of the by-pass signal to form a feature collection; calculating mahalanobis distance values, including a mahalanobis value of a reference integrated circuit and a mahalanobis value of the to-be-detected integrated circuit, of the feature collection; comparing the mahalanobis value of the reference integrated circuit with that of the to-be-detected integrated circuit, and performing hardware Trojan horse detection according to a comparison result. By the hardware Trojan horse detection method and the hardware Trojan horse detection system which have the advantages of simple algorithm and short detection time, distinguishability and efficiency of hardware Trojan horse detection in integrated circuit testing are effectively improved, and any cost for hardware is not generated.

In binaural stereo coding, only one monaural channel is encoded. An additional layer holds the parameters to retrieve the left and right signal. An encoder is disclosed which links transient information extracted from the mono encoded signal to parametric multi-channel layers to provide increased performance. Transient positions can either be directly derived from the bit-stream or be estimated from other encoded parameters (e.g. window-switching flag in mp3).

Method for determining distance to target using a multitone nonlinear radar system comprising providing a transmitter that transmits a signal comprising at least two predetermined frequency components; receiving transmitted signal upon reflection from target; determining the phase relationships of the frequency components when signal strikes target; determining distance the signal has travelled to target based upon the phase relationship of the frequency signal components at the time of reflection from target; computing the distance to target. A system comprising a transmitter subsystem that transmits radar signal comprising at least two frequency components; a receiver subsystem configured to receive a return signal comprising intermodulation and harmonic products; at least one processor configured to extract frequency samples from the return signal within a frequency range, apply a window function to the extracted frequency samples and perform an inverse fast Fourier transform on the resulting function to create a range profile.

The invention provides an internal-external double-electrode type miniature hemispherical resonance gyroscope and a preparation method thereof. The internal-external double-electrode type miniature hemispherical resonance gyroscope comprises a single-crystal silicon substrate, a central fixed supporting column, a miniature hemispherical resonator, external electrodes, external-electrode metal welding plates, a glass substrate, metal leads, round welding wire discs, external-electrode metal connecting columns, internal electrodes and a seed layer. The internal-external double-electrode type miniature hemispherical resonance gyroscope and the preparation method provided by the invention have the beneficial effects that an MEMS bulk silicon processing process and a surface silicon processing process are combined for manufacture; different driving and detection modes and different working modes can be provided, and the working in a system needing complex control can be achieved; the internal electrodes and the external electrodes can be utilized for respectively carrying out driving and detection, the parasitic capacitance between a driving electrode and a detection electrode can be reduced and the detection accuracy can be improved; and the metal leads and the round welding wire discs are provided for the internal electrodes and the outer electrode so as to bring convenience for signal application and signal extraction.

The invention discloses a wavelet transform and variable-step-size LMS (least mean square) adaptive filtering based signal denoising method which comprises the following steps that: 1, signal receiving and synchronous storage: a data processor synchronously stores received signals into a data memory so as to obtain a sampling sequence X (k) which is a one-dimensional signal; 2, high-frequency signal extraction: the data processor carries out wavelet transform on the currently received one-dimensional signal X (k) and extracts high-frequency signals; and 3, LMS adaptive filtering: the data processor invokes the high-frequency signals extracted by an LMS adaptive filter to carry out LMS error calculation so as to obtain output signals subjected to filtering, and carries out adjustment on the parameters of the filter according to error signals, so that the output signals tend to interference signals. The method disclosed by the invention is simple in steps, reasonable in design, convenient to realize, and good in denoising effect; and the denoising process is performed through the combination of wavelet transform and variable-step-size LMS adaptive filtering, so that the filtering effect and the tracking speed are effectively increased.

A photonic integrated circuit (PIC) for a PON transceiver comprises a single monolithic chip having a modulated transmitter laser diode of a first wavelength, λ1, for generating a first communication signal outgoing from the chip via an input / output port and a receiving photodetector for receiving a second communication signal of a second wavelength, λ2, onto chip incoming from the input / output port and a monitoring photodetector for receiving a portion of the first communication signal to monitor the laser diode output power. In one embodiment, the chip is provided with multimode (MM) coupler set to direct a substantial portion of the incoming communication signal to the receiving photodetector and to direct a substantial portion of the outgoing communication signal to the input / output port. A filter may be inserted before the receiving photodetector and / or the laser diode to extract any remaining and undesired signal to either such electro-optic elements. In another embodiment, the laser diode, power monitoring photodetector and the receiving photodetector are collinear in the same chip having a common waveguide where the power monitoring photodetector is capable of both monitoring power and insuring no backward reflecting light of the laser diode reaches the receiving photodiode through it absorption of such light. The active region of the power monitoring photodetector can be set to be absorptive of incoming of backward reflected polarized light of both the TE and TM polarization modes respectively from the chip input or the on-chip laser diode.

A predistorter compensates, with high accuracy, for a distortion in each frequency band by a power amplifier that amplifies a transmission signal containing multiple frequency bands whose center frequencies are widely spaced apart. Signals of the respective frequency bands are extracted by multiple band signal extractors from the input signal containing transmission signals of multiple frequency bands; differences between the extracted signals and the output signal from the power amplifier are detected by multiple difference detectors in the respective bands; the detected difference signals are used as reference signals to read out compensation data from look-up tables for the respective frequency bands; the compensation data is added by multiple adders to the extracted transmission signals of the respective frequency bands; and the added outputs are combined by a combiner to provide the output signal from the predistorter.

In a method for improving signal extraction in a code division multiple access (CDMA) telecommunications system, a first iteration of interference cancellation is performed on the basis of bit rates for every signal which are the same as those in a previous frame of the same signal. Filtered and down-converted signals are demodulated in Rake receivers to provide output signals corresponding to decision variables and channel estimates. The decision variables are limited and remodulated and respread prior to the signals being reconstructed using the channel estimates. The reconstructed signals are summed, and each signal is subtracted from the sum to provide an ‘interference’ signal which is then used to obtain the individual signals. Each signal is then demodulated a second time in another Rake receiver to provide a tentative DPDCH signal, a TFI signal, a TPC signal and a SNI signal. The TFI signal is processed to provide a signal indicative of the bit rate which is used to both decode the DPDCH signal providing a data output and to provide an estimate of the bit rate for a subsequent frame of the same signal.

The invention relates to the technical field of medical treatment products, in particular to a blood oxygen measurer and a method. The blood oxygen measurer comprises a light current signal acquisition unit, a signal conversion unit, an environment light signal filtering unit, a voltage signal amplification unit, an analog-to-digital conversion unit, a waveform signal extraction unit, a noise analysis unit, a waveform processing unit and a blood oxygen data calculating unit which are successively connected according to a signal flow direction, and the environment light signal filtering unit is connected with the signal conversion unit and used for filtering interference of environment light signals. The blood oxygen measurer is provided with the environment light signal filtering unit, when blood oxygen is measured, saturation of measured signals due to interference of environment light is avoided, so that the blood oxygen can be measured in various environments, the service range of the blood oxygen measurer is greatly expanded, and popularization is quite high.