94 results about "Reflection coefficient" patented technology

The application discloses a kind of angle, distance and speed joint estimation method for MIMO-AFDM ISAC system, constructs single base MIMO-ISAC system based on AFDM, pilot and QPSK data are mapped to DAF domain by transmitting end, and ISAC waveform of adaptive high mobility is generated by IDAFT and CPP insertion;Establish echo three-dimensional DAF domain tensor model, after removing the chirp cycle prefix of echo signal by receiving end, execute discrete affine Fourier transform and fast Fourier transform processing;Data cube is projected in beam domain, time delay compensation and matching normalization are carried out, and parameter decoupling is realized;Three-dimensional power cube is constructed, and target detection is completed by 3D CA-CFAR detection, non-maximum suppression and secondary interpolation;Mapping target angle, distance, speed parameter, estimating complex reflection coefficient and output.The application can obtain lower angle, distance and speed estimation root mean square error under the condition of different receiving array aperture, different coherent processing time length and different target quantity.

This invention relates to the field of seismic data processing technology, specifically disclosing a method for removing strong reflection shielding in hidden river channels based on adaptive hybrid L0-L1 norm. The method includes: first, establishing an optimization objective function based on Bayes' theorem using hybrid L0-L1 norm; second, dynamically adjusting the L0-L1 norm weights using an adaptive weight function driven by the seismic signal, combined with reflection coefficient amplitude and residual information, enhancing sparsity constraints in strong reflection zones and reducing constraint strength in weak reflection zones; then, constructing a convex upper bound for the objective function using a minimization framework, and solving it iteratively in stages using an accelerated rapid iterative threshold shrinkage algorithm, while incorporating prior knowledge of seismic wave propagation laws and river channel deposition patterns to ensure the geological rationality of the solution. This invention solves the technical problems of traditional sparse processing methods, such as fixed parameters, lack of geological constraints, and inability to simultaneously address strong reflection suppression and weak signal protection, significantly improving the separation accuracy of strong reflections and the recovery rate of weak signals, effectively overcoming the strong reflection shielding effect.

The application discloses a kind of through type radio frequency microwave vector analysis device and method, device includes radio frequency front end and down conversion module, digital acquisition and processing module and control and interactive module.Radio frequency front end and down conversion module are used for the transmission of radio frequency signal, two-way coupling sampling and coherent down conversion;Digital acquisition and processing module are used for collecting signal and processing, obtain pure incident wave signal and reflected wave signal;Control and interactive module are used for controlling each module, and carry out man-machine interaction.The application is realized by using through type measurement architecture, under the premise that the signal transmission of measured system is not interrupted, realizes the online vector analysis of radio frequency signal, and does not need built-in signal source, and then complete vector parameter such as reflection coefficient, impedance, standing wave ratio can be accurately calculated.

A circuit for measuring the reflection coefficient and a method for testing and calibration are proposed. The measurement circuit consists of two cascaded orthogonal directional couplers, with the through-terminal and coupling terminals of the two couplers connected to the same reactive element. Measuring the voltage between the through-terminal and coupling terminals under short-circuit conditions allows for calibration of the reflection coefficient of the reactive element. Based on the measured voltages between the through-terminal and coupling terminals of the two orthogonal directional couplers, a system of two nonlinear equations can be constructed. Solving this system yields the real and imaginary parts of the reflection coefficient of the load under test.

This invention discloses a method and apparatus for noise-resistant frequency compensation of seismic data, relating to the fields of compressed sensing and seismic exploration design. The method includes: performing spectral analysis on the original seismic data to determine the expected frequency broadening range; performing autocorrelation calculation on the original seismic data to obtain wavelet-like waveform data; using the wavelet-like waveform data as simulated wavelet data, inputting iterative solutions to the compressed sensing noise-resistant frequency extension basis function to obtain the full bandwidth reflection coefficient; concatenating the full bandwidth spectrum with the original seismic data spectrum to obtain the extended spectrum; and performing an inverse Fourier transform on the extended spectrum to obtain the noise-resistant frequency extension data. This invention is based on the compressed sensing framework, utilizes the Shearlet denoising basis function to constrain the frequency extension basis function, and constructs a noise-resistant frequency extension basis function based on compressed sensing, achieving good high- and low-frequency compensation effects for seismic data under low signal-to-noise ratio conditions.

The application provides a nondestructive testing method for the bonding strength of a coating of a semiconductor device shell, and belongs to the technical field of semiconductor device testing. The method solves the problem that the bonding strength of a coating and a substrate cannot be nondestructively evaluated in the prior art. The method comprises the following steps: arranging an acoustic wave coupling medium and an acoustic wave sensor on the surface of the coating, selecting at least three laser impact points, focusing a laser beam generated by a pulsed laser on the impact points, collecting a longitudinal wave signal after laser impact, reading a first echo signal peak voltage and a second echo signal peak voltage, calculating an acoustic pressure reflection coefficient R , performing laser impact on the same impact points for a second time at the same energy density, obtaining a reflection coefficient change amount R , calculating an average value R of the reflection coefficient change amounts R of the multiple impact points, and determining whether the bonding strength of the coating and the substrate meets a requirement according to the average value R avg When the average value R avg is greater than 0.05, it is determined that the bonding strength of the coating and the substrate does not meet the requirement, otherwise, the bonding strength of the coating and the substrate meets the requirement. The application can be used for the rapid and nondestructive evaluation of the bonding strength of a coating of a semiconductor device shell.

The invention discloses an inversion method and device for a longitudinal-transverse wave velocity ratio of a coal measure strata, and the method comprises the steps: determining the longitudinal-transverse wave velocity ratio reflectivity of a target interval according to the prestack angle gather data of the target interval, and extracting the attribute data of the longitudinal-transverse wave velocity ratio reflectivity through employing the AVO technology; according to the longitudinal and transverse wave velocity ratio curve, the attribute data of the longitudinal and transverse wave velocity ratio reflectivity and preset wavelet extraction time window parameters, wavelet extraction is carried out on the target layer section through the wavelet extraction technology; the longitudinal and transverse wave velocity ratio curve is determined according to logging data; and according to the wavelet and the attribute data of the velocity ratio reflectivity of the longitudinal and transverse waves, performing post-stack compressed sensing reflection coefficient inversion to obtain an inversion result of the velocity ratio reflectivity of the longitudinal and transverse waves. According to the invention, a stable inversion result of the longitudinal and transverse wave velocity ratio can be effectively obtained.

The application discloses a kind of λ / 4 stepped impedance transformation method and system.Therein, the method includes: in the impedance mismatching of partial discharge ultrahigh frequency load impedance and the characteristic impedance of partial discharge ultrahigh frequency measurement system, access λ / 4 stepped impedance transformation two-port network, the load impedance is wave impedance;According to characteristic impedance Z 0, wave impedance Z L And the characteristic impedance of two-section λ / 4 transmission line Z 1, Z 2, determine partial voltage reflection coefficient;According to the partial voltage reflection coefficient, determine total voltage reflection coefficient;According to the total voltage reflection coefficient, broaden the working frequency band of λ / 4 stepped impedance transformer.Therefore, break through the limitation of direct matching, by the progressive stepped impedance matching mode of sensor element, realize partial discharge ultrahigh frequency signal sensor element and subsequent radio frequency processing circuit good matching, thereby reduce the partial discharge ultrahigh frequency signal attenuation caused by impedance mismatching.

A transparent antenna includes a transparent substrate; and a metal thin wire layer on an upper side of the transparent substrate. The transparent substrate has a thickness of 300 μm or less. The metal thin wire layer has an opening ratio of 80% or more. When a metal conductor having a surface resistivity ρΩ / sq is placed parallel to the transparent antenna 0.15 mm apart, an input reflection coefficient S11(ρ, f) and a radiation efficiency Eff(ρ, f) at a frequency f satisfy relationsS11(0.1Ω / sq,f1 GHz)<−3 dB,S11(0.1Ω / sq,f2 GHz)<−3 dB, and|Eff(0.1Ω / sq,f1 GHz)−Eff(0.1Ω / sq,f2 GHz)|<25%at two frequencies f1 and f2 that are between 2 GHz and 50 GHz.

The application provides a longitudinal and transverse wave separation water exploration method and system based on a reflection coefficient and a stress gradient, and the method comprises the following steps: collecting original seismic record data of a tunnel site and performing pretreatment; a longitudinal and transverse wave separation method is used to separate longitudinal waves and transverse waves from the pretreated seismic wave data; wherein, F-K filtering separates wave fields with different apparent velocities through frequency-wavenumber domain transformation, and realizes preliminary separation of longitudinal waves and transverse waves; for the overlapping part of the longitudinal waves and the transverse waves remaining in the F-K domain; linear Radon transformation is used to map the data from the time-space domain to the ray parameter domain, and further separate the wave fields with similar apparent velocities; a polarization filter is used to finally separate the longitudinal waves and the transverse waves by using the polarization characteristics; based on the separated longitudinal waves and the transverse waves, reflection coefficient imaging and stress gradient imaging are calculated respectively; and according to the reflection coefficient imaging result and the stress gradient imaging result, the underground water occurrence condition is identified. The identification precision of the underground water occurrence condition is improved.

This invention relates to a dual-band non-frequency-doubled high-power microwave oscillator with a coaxial drift cavity, comprising a cathode holder, a ring cathode, an anode outer cylinder, a first drift cavity, a first slow-wave structure, a second drift cavity, a second slow-wave structure, an output waveguide, an inner conductor, and an external guiding magnetic field. The entire structure is rotationally symmetrical about its central axis, and the components are arranged coaxially along the electron beam transmission direction, forming a complete electron beam transmission and microwave generation path. This invention uses a coaxial drift cavity to isolate the two slow-wave structures, achieving a reflection coefficient greater than 0.99 for the microwaves generated by the two slow-wave structures, exhibiting high reflection characteristics. This effectively isolates the two slow-wave structures from each other, avoiding beam-wave interaction interference. This overcomes the limitation of previous devices where the output frequency of dual-frequency microwaves was approximately a harmonic relationship, allowing for more flexible selection of the operating frequency.

The application provides a kind of concrete nondestructive testing method, it is related to concrete detection technical field.It includes: S1, using ultrasonic wave, electromagnetic wave and infrared thermal imaging three detection methods, respectively collect the detection data of concrete test piece;S2, the detection data is preprocessed and feature extraction, obtains the multidimensional feature vector including ultrasonic wave velocity, first wave arrival time, electromagnetic wave reflection coefficient, infrared temperature distribution;S3, based on D-S evidence theory, constructs the probability distribution function of three detection methods to concrete defect type, and carries out evidence fusion, obtains preliminary fusion recognition result;S4, the multidimensional feature vector is input into the neural network model after training, carries out defect classification and positioning identification, outputs final recognition result;S5, according to the final recognition result judges concrete health state, defect type and position, and outputs detection report.The application has the effect that the accuracy and reliability of nondestructive testing are high.

The application discloses a kind of intelligent reflecting surface assisted computational imaging method, it is related to wireless communication field.System is composed of multiple single antenna terminal equipment, an intelligent reflecting surface comprising several reflecting units and a multi-antenna base station, while there is an object to be imaged.Base station adjusts the reflection coefficient of intelligent reflecting surface with the criterion of minimizing the mean square error of imaging.All terminal equipment simultaneously emits sensing signal to the object to be imaged in environment, part of signal reaches base station after scattering through the object to be imaged and reflecting by intelligent reflecting surface, another part of signal reaches base station directly after scattering through the object to be imaged, and base station uses best linear unbiased estimator to realize the imaging of scatterer.The application provides an effective method for intelligent reflecting surface assisted wireless computational imaging of three-dimensional object.

This application provides a core dielectric characteristic detection probe, detection method, and detection device, belonging to the field of core electrical testing and dielectric spectrum measurement technology. The core dielectric characteristic detection probe includes a probe structure. When performing a displacement experiment on the core, the working end face of the probe structure is adapted to clamp the core and continuously emit electromagnetic waves toward the core and receive the reflection coefficient to obtain the real-time electromagnetic parameters of the core. In the displacement experiment, the liquid can be discharged through the drainage groove on the working end face, enabling the probe structure to complete the clamping action of the core in the displacement experiment. It can also simultaneously perform dielectric spectrum acquisition in the displacement experiment, thereby realizing real-time and continuous dielectric spectrum acquisition in the displacement experiment through the probe structure.

The application discloses a hydraulic system oil leakage detection method based on a press, relates to the technical field of hydraulic system oil leakage detection, and realizes accurate detection through high-emissivity reference plate auxiliary radiation inversion and contrast verification. The high-emissivity reference plate is arranged beside the detected target, the surface temperature of the reference plate is obtained, the equivalent radiation of the reference plate is calculated according to the Stefan-Boltzmann law, the image of the detected target is collected by using an infrared thermal imager, the target is divided into regions, and the equivalent radiation of the target is calculated; the above measurement is repeated after the temperature of the reference plate is changed, equations are established by using two groups of radiation data, and the equivalent emissivity of the detected target and the real surface temperature of the target are solved. The dry metal surface without oil is set as a dry contrast area, the equivalent emissivity of the dry contrast area is calculated, a difference value of the reflection coefficient is obtained through comparison, a leakage suspicious area is marked in combination with a temperature underestimation and an environmental temperature, a leakage positioning list is generated by taking a schematic diagram of a hydraulic system loop corresponding to the suspicious area, and whether external leakage exists is determined according to the leakage positioning list.

This invention discloses a high-speed cable optimization method and system based on impedance continuity compensation, relating to the field of high-speed cable optimization. The method includes: identifying the location, amplitude, and type of each impedance abrupt change point; calculating the reflection phase difference between any two abrupt change points; identifying the locations of coherent traps where reflected signals from multiple abrupt change points coherently superimpose within the Nyquist frequency range; constructing a coherence elimination objective function; determining compensation parameters for geometric pre-compensation, dielectric constant gradient compensation, and active dynamic compensation; adjusting the reflection coefficient amplitude of the abrupt change points according to the target residual impedance abrupt change amplitude; changing the reflection phase distribution according to the optimal control parameters of dielectric constant gradient compensation; and introducing an adjustable reflection coefficient to adjust the standing wave condition according to the target terminal matching impedance value. The advantages of this invention are: effectively eliminating the coherent superposition effect of multi-level reflections in high-speed cables, achieving impedance continuity and signal integrity of high-speed cables across the entire frequency band.

Provided are a channel separation method and system. The method includes: switching, by an intelligent reflecting surface or a relay between a base station and a terminal, a codebook of reflected pilot signals to a new codebook at a specified symbol position based on a pre-configured codebook reflection coefficient.

The application provides a phase shifter and a communication device, and belongs to the technical field of communication. In the scheme provided by the application, at least one of the first reflection load and the second reflection load in the phase shifter is a target reflection load, and the material of the target reflection load comprises vanadium dioxide. Since the feeding structure in the phase shifter can load voltage to the target reflection load, the phase change of vanadium dioxide in the target reflection load can be caused, and the reflection coefficient of the target reflection load is adjusted. Therefore, the phase shift amount of the phase shifter can be flexibly adjusted, and the use flexibility of the phase shifter is effectively improved.

The application discloses an imaging method, device, equipment, medium and product of seismic waves. The method comprises the following steps: acquiring seismic data of a region to be imaged; performing amplitude compensation and Laplace filtering on an original reverse-time migration result to obtain a first target result; calculating a three-dimensional reflection coefficient of an original FWI velocity model and performing dip filtering to obtain a second target result; calculating a phase shift operator and an amplitude weighting coefficient according to the target results, and performing weighted processing on the target results to obtain a target imaging result corresponding to the region to be imaged. The original reverse-time migration result and the FWI calculation result are optimized and then weighted and superimposed, the energy of low wave numbers and high wave numbers in the seismic waves is enhanced, the frequency band range of conventional migration is expanded, the imaging result is more stereoscopic, the boundary line and the interface horizon change can be displayed, the full-bandwidth seismic data is mapped into a high-resolution seismic profile in the depth domain in the time domain, and the quality of the seismic wave imaging is improved.

This invention is a method for inverting azimuth difference seismic data in inclined fractured rocks. Previous AVAZ inversion methods for fracture parameters were mostly based on the HTI medium assumption, with insufficient consideration for fracture dip angle. The fixed form of the inversion constraint terms made it difficult to adapt to changes in parameter statistical characteristics, and the regularization parameters were all manually adjusted, affecting inversion accuracy and efficiency. This invention establishes an approximate formula for the reflection coefficient of the TTI medium, characterized by the P-wave and S-wave velocities, density, and fracture elastic parameters of the background medium. It utilizes pre-stack azimuth difference data to perform AVAZ inversion of fracture parameters. Dynamic sparsity constraints are introduced, dynamically adjusting the sparsity of the constraints based on data characteristics, and a covariance matrix is ​​introduced to consider the statistical regularity between parameters. Combining iterative reweighted least squares and adaptive regularization parameter acquisition methods, the dynamic constraint inverse problem is transformed into a weighted... L A 2-norm objective function is used to achieve a stable solution. Data testing shows that this invention can effectively improve the inversion accuracy of crack elastic parameters.

This invention discloses a path loss modeling method for RIS-assisted communication systems, comprising: establishing a three-dimensional coordinate system with the RIS center as the coordinate center, and constructing a path loss model dataset; setting the adjustment step size to s, and dividing the RIS electromagnetic unit into regularly sized RIS electromagnetic blocks; constructing a joint normalized power radiation pattern of the transmitting antenna, RIS electromagnetic blocks, and receiving antenna; constructing the total phase change term of the signal after reflection by the RIS electromagnetic blocks; constructing the programmable reflection coefficient of the RIS electromagnetic unit; constructing a double-superposition reflection gain model of the RIS electromagnetic unit performance; and integrating these to obtain the final path loss model method. This invention achieves a unified theoretical framework for propagation characteristics from near field to far field, significantly improves computational efficiency, and can be dynamically adjusted according to actual scenario requirements, achieving a dynamic balance between computational efficiency and system performance, providing engineering support for RIS to achieve low-latency, deployable systems in real dynamic environments.

This application provides a method, device, and storage medium for predicting fracture density based on azimuth anisotropy, belonging to the field of geophysical research technology. The method includes: substituting fracture-related test data into a prediction formula to calculate the P-wave reflection coefficient. The prediction formula is an approximate formula for the P-wave reflection coefficient of a transversely isotropic medium, and the right-hand side variable of the prediction formula includes at least the fracture density in different directions; extracting well-side seismic trace data from azimuth-based stacked traces and deconvolving it to obtain a seismic wavelet; calculating the P-wave reflection coefficient data volume of the target work area based on the seismic wavelet and azimuth-based stacked traces; and inverting the fracture density in different directions of the target work area using an interpolated initial model as a constraint. The above method is based on an improved prediction formula, whose right-hand side variable includes the fracture density in different directions, realizing direct inversion of fracture density, reducing inversion time and accumulated errors, and improving the efficiency and accuracy of fracture density prediction.

This invention discloses a method for elastic modulus inversion based on diffraction wave information. The method includes: acquiring a three-dimensional seismic data volume of diffraction waves; obtaining near-, middle-, and far-field angularly stacked data of diffraction waves based on the three-dimensional seismic data volume; obtaining a P-wave diffraction coefficient formula suitable for pre-stack inversion based on the P-wave reflection coefficient formula; determining the diffraction coefficient based on the P-wave diffraction coefficient formula; obtaining near-, middle-, and far-field angularly stacked data of the whole wavefield based on layer interpretation; obtaining wavelet data corresponding to near-, middle-, and far-field gathers based on the near-, middle-, and far-field angularly stacked data of the whole wavefield; converting the layer velocity in the whole-wavefield seismic processing into layer velocity P-wave and S-wave modulus and density; using the layer velocity P-wave and S-wave modulus and density as background parameters of the inversion objective function; constructing and inverting the diffraction wave elastic modulus inversion objective function based on the wavelet data and diffraction coefficients; obtaining the elastic modulus anomaly in the target layer caused by heterogeneous disturbance by solving the objective function; and using the elastic modulus anomaly to identify and predict heterogeneous bodies in the strata.

The abstract pertains to an inductance measurement device that includes a circulator and a resonant tank circuit. The circulator is designed to receive a signal from a signal generator and direct it to the resonant tank circuit, which is configured to reflect the signal. The resonant tank circuit includes an inductor comprising a magnetostrictive material. The device also includes a processing device that receives the reflected signal from the circulator and processes it to determine a reflection coefficient.

The application relates to a reconfigurable surface-assisted index modulation method based on non-orthogonal multiple access, and belongs to the technical field of communication. The method comprises the following steps: S1, establishing an RIS-IM-NOMA system model, and defining a reflection coefficient matrix and a detection mode; S2, deducing and analyzing a theoretical upper limit of the bit error rate of the system model; S3, theoretically analyzing the performance of the spectral efficiency of the system model and putting forward a user-to-user spectral efficiency fairness problem; and S4, optimizing and designing a power distribution mode to improve system fairness.