31 results about "Time domain signal processing" patented technology

The invention relates to an underwater target gammatone discrete wavelet coefficient auditory feature extraction method. Noisy data measured actually are preprocessed at first on the basis of Fourier transform and logarithm compression and in incorporation with a gammatone auditory filter bank and discrete wavelet transform to enable target signals to be approximately stable in the short time; Fourier transform is conduced on the preprocessed data, time-domain signal processing is converted into frequency-domain signal processing, auditory filtering and logarithm compression are conducted on the preprocessed data through the gammatone auditory filter bank, discrete wavelet transform is conducted on the data on which logarithm compression is conducted at last, and the dimensionality of the data is reduced. The underwater target gammatone discrete wavelet coefficient auditory feature extraction method can extract effective auditory features of underwater target radiation noise, thereby improving the correct recognition rate of the underwater target.

The present invention discloses a signal processing method and a data processing method and apparatus. A time-domain to frequency-domain signal processing method includes: pre-processing time-domain data; pre-rotating the pre-processed data by using a rotation factor a·WNn+0.5; performing a discrete Fourier transform (DFT) of N / 4 points on the pre-rotated data; and post-rotating the data transformed by the DFT by using a rotation factor b·WNn+0.5 to obtain frequency-domain data. A frequency-domain to time-domain signal processing method includes: twiddling frequency-domain data; pre-rotating the twiddled data by using a rotation factor c·WNn+0.5; performing a DFT of N / 4 points on the pre-rotated data; and post-rotating the data transformed by the DFT by using a rotation factor d·WNn+0.5; and post-processing the post-rotated data to obtain time-domain data. The present invention increases the efficiency of signal processing.

The invention discloses a time-domain signal processing method for through casing differential resistivity logging. The time-domain signal processing method comprises the steps that transient electromagnetic induction received waveforms at four moments of forward turn-on, forward turn-off, reverse turn-on and reverse turn-off are obtained; the transient electromagnetic induction received waveformsat the adjacent depth points subtract to obtain the responding difference waveform 1, the responding difference waveform 2 and the responding difference waveform 3; the responding difference at the coupling position is replaced through the responding difference at the adjacent depth points, so that the coupling influence is removed; the maximum values of the responding difference waveform 1, theresponding difference waveform 2 and the responding difference waveform 3 at the four moments are selected, and the maximum values are converted to stratum conductivity difference curves; the stratumconductivity difference curve at any moment in any responding difference waveform is selected and integrated to obtain a stratum conductivity curve of the measured well section; the same method is applied to other moments of the responding difference waveforms to generate the stratum conductivity curve of the corresponding well section; the time-domain signal processing method is applied to the four moments of the other two responding difference waveforms to generate the stratum conductivity curve of the corresponding well section; and all the stratum conductivity curves are weighted and added, and the reciprocal value is taken to obtain the stratum conductivity curve.

In order to improve the accuracy of modulation recognition, the invention provides a signal modulation recognition algorithm based on data enhancement and a convolutional neural network. The method comprises the following steps: firstly, processing a time domain signal in a data set RML2016.10a into a constellation diagram, and dividing pictures into a training set and a test set according to a proportion of 8: 2; secondly, processing the training sets by using four data enhancement methods of rotation, random erasing, overturning and CutMix to obtain four enhanced training sets; respectively inputting the four types of enhanced training sets into a GoogleNet network for training, and continuously optimizing network parameters according to back propagation to obtain a trained network; and finally, sending the test set into the trained GoogleNet network for testing, drawing a curve of which the correct rate changes along with the signal-to-noise ratio, and comparing the improvement effects of different data enhancement methods on the correct recognition rate to obtain an optimal data enhancement method. Compared with other modulation recognition algorithms without data enhancement, the method has the advantages that the risk of model overfitting is reduced, and the generalization ability of the model is improved.

A chemical detection system performs controlled exposures to diagnose the pneumatic components and chemical sensors prior to measuring a chemical emission. A control module provides the system control and data processing to perform the diagnosis. The control module manipulates an emission sample retrieval system to provide precise exposure during the diagnostic routines. A sensor interface circuit interrogates the chemical sensors and stores the data for analysis. The chemical sensor exhibits predictable changes in response during predetermined exposure scenarios. By utilizing numerous time domain signal processing techniques, both system and sensor level fault conditions are determined.

The invention discloses a time-domain signal processing method for differential resistivity logging through casing: acquiring transient electromagnetic induction receiving waveforms at four moments of forward conduction, forward turn-off, reverse conduction and reverse turn-off; Response difference waveforms 1, 2, and 3 are obtained by subtracting the received waveforms of electromagnetic induction at adjacent depth points; the response difference of adjacent depth points replaces the response difference at the collar to remove the influence of the collar; respectively select the response difference waveforms 1 and 2 at four times , 3, the maximum value is converted into the formation conductivity difference curve; the formation conductivity difference curve at any time in any response difference waveform is integrated to obtain the formation conductivity curve of the measured well section; the same The method is applied to other moments of the response difference waveform to generate the formation conductivity curve of the corresponding well section; the above method is applied to the other two response difference waveforms at four moments to generate the formation conductivity curve of the corresponding well section; The curves are weighted and added together, and the reciprocal is taken to obtain the formation resistivity curve.

Embodiments include digital signal processing units, a transmitting device for a wireless communication system and methods of processing a composite time domain signal having a plurality of parallel and independent signals that collectively form a parallel communication. It is proposed a new waveform configuration suitable for 5G and that is able to reduce out-of-band (OOB) emissions which are received on a first time domain signal associated to a first sub-band where the OOB emissions originate from an OFDM time domain signal associated with a second sub-band adjacent to the first sub-band. The proposed solution is partly based on filtered-OFDM with the exception that sub-band filtering is not performed on all the samples of the stream of OFDM symbols. Instead, filtering is performed only, for each OFDM time domain signal, where transition occurs between consecutive OFDM symbols.

The invention discloses a wind profile radar rainfall and non-rainfall adaptive detection system and method. The system comprises system control module, a signal processing module, a digital intermediate frequency receiver plate, an industrial control computer, a data terminal computer and a data processing module. The system control module controls the atmosphere wind field detection process. The digital intermediate frequency receiver plate receives a radio echo signal and obtains domain signals in digital processing. The signal processing module processed the domain signals into atmosphere wind field power spectrum signals. The data processing module processes and analyzes the atmosphere wind field power spectrum signals and automatically configures corresponding detection parameters. The established adaptive detection system automatically determines whether there is rainfall or not and configures corresponding detection parameters in the detection process through a wind profile radar, so that the adaptive detection of the atmosphere wind field in rainfall or non-rainfall weather is achieved, the atmosphere wind field information under different weather conditions can be accurately measured, and better application in meteorological research and weather forecast is achieved.

The invention discloses a method for estimating the deployment depth of a vector hydrophone. The method comprises: receiving time-domain signals of broadband sound pressure radiated by a sound source and three-component particle vibration velocity, and processing the time-domain signals to obtain x, y and z Acoustic energy flow in three directions; use the acoustic energy flow in the x direction and y direction to estimate the azimuth angle of the sound source and synthesize the horizontal acoustic energy flow; estimate the arrival angle of the sound source by the ratio of the acoustic energy flow in the z direction and the horizontal acoustic energy flow ;According to the estimated value of the arrival angle of the sound source, combined with the sound velocity profile, calculate the time delay template value of the direct wave and the bottom reflection wave corresponding to the depth of the hydrophone of different vectors under the arrival angle; obtain the estimated arrival time delay value of the direct wave and the bottom reflection wave ; Calculate the difference between the estimated arrival time delay of the direct wave and the seabed reflected wave and the delay template value, and use the depth corresponding to the delay template value with the smallest difference as the estimated value of the vector hydrophone deployment depth.

The invention relates to an underwater target gammatone discrete wavelet coefficient auditory feature extraction method. Noisy data measured actually are preprocessed at first on the basis of Fourier transform and logarithm compression and in incorporation with a gammatone auditory filter bank and discrete wavelet transform to enable target signals to be approximately stable in the short time; Fourier transform is conduced on the preprocessed data, time-domain signal processing is converted into frequency-domain signal processing, auditory filtering and logarithm compression are conducted on the preprocessed data through the gammatone auditory filter bank, discrete wavelet transform is conducted on the data on which logarithm compression is conducted at last, and the dimensionality of the data is reduced. The underwater target gammatone discrete wavelet coefficient auditory feature extraction method can extract effective auditory features of underwater target radiation noise, thereby improving the correct recognition rate of the underwater target.

The invention discloses a device for realizing long time domain signal processing. The device stores a Bragg acousto-optic relevant optical signal in an optical storage array and a storage medium through optical storage technology, and then reads the stored optical signal for signal processing. The technology aims to the technical field of the relevant operation of a long time domain signal. The device has the outstanding advantage that: the long time domain signal, particularly a signal with the time-bandwidth product more than 10 can be processed through the method.

A method for extracting auditory features of underwater target gammachirp cepstrum coefficients proposed by the present invention is based on Fourier transform and logarithmic compression, combined with gammachirp auditory filter banks, firstly preprocesses the measured noise data to make the target The signal is expressed as approximately stable in a short period of time, and then Fourier transform is performed on the preprocessed data, and the time-domain signal processing is converted into a frequency-domain signal for processing, and then it is auditory filtered through the gammachirp auditory filter bank and used Logarithmic compression, and finally perform discrete cosine transform on the logarithmically compressed data to reduce its dimensionality. This feature extraction method based on the gammachirp frequency auditory perception cepstral coefficient can extract effective auditory features of underwater target radiation noise, thereby improving the correct recognition rate of underwater targets.

Embodiments of the present invention provide a channel estimation method, device, and receiver. The channel estimation method is used for a receiving end based on a DFT-s-OFDM system, including: receiving the first time signal sent by the transmitting end of the DFT-s-OFDM system Domain signal, the first time domain signal is the transmission signal obtained by the sending end using a preset PTRS configuration method, the preset PTRS configuration method includes inserting PTRS before performing DFT on the PUSCH data; performing time domain signal on the first time domain signal processing to obtain a PTRS time-domain signal for channel estimation; perform channel estimation according to the PTRS time-domain signal, and obtain a channel response at a frequency domain position where the PTRS is located. Therefore, the present invention can directly estimate the frequency domain channel response of the time-frequency resource position where the PTRS signal is located in the DFT-s-OFDM system, and improves the channel estimation capability based on the DFT-s-OFDM system.