37 results about "Incident field" patented technology

The embodiment of the invention provides a path loss determination method and device, a storage medium and an electronic device, and the method comprises the steps: determining a superposition field image of a target grid scene according to a first image, a second image and an incident field image of the target grid scene, the first image is used for indicating the position of the first object in the target grid scene, and the second image is used for indicating the position of the second object in the target grid scene; determining a first loss function according to the incident field image and the superimposed field image; determining a second loss function according to the superimposed field image and the drive test data of the target grid scene; determining a target loss function according to the first loss function and the second loss function; and training a neural network model according to the target loss function so as to determine the path loss of the target grid scene through the trained neural network model. By means of the method, the problem that accuracy and calculation efficiency cannot be both considered in a path loss estimation method in the prior art can be solved.

The invention discloses an electromagnetic scattering calculation method based on deep learning under the condition that the shape and electrical parameters of a scatterer are not completely known. The electromagnetic scattering calculation method comprises the following steps: step 1, inputting electrical parameters of a known part of the scatterer, such as relative dielectric constant and magnetic conductivity, an incident field, a small amount of scattered field (observation / measurement) data and position coordinates of a to-be-solved scattered field; 2, solving an internal total field under the condition that only the known part of the scatterer exists and the unknown part does not exist by adopting a moment method; 3, inputting a small amount of scattered field (observation / measurement) data, an internal total field under the condition that only the known part of the scatterer exists and the unknown part does not exist, and the electrical parameters of the known part of the scatterer into a deep learning neural network, and obtaining the electrical parameters of the unknown part of the scatterer through the network, such as a relative dielectric constant and magnetic conductivity; 4, inputting the internal total field under the condition that only the known part of the scatterer exists and the unknown part does not exist, the electrical parameters of the unknown part of the scatterer and the electrical parameters of the known part of the scatterer into another neural network, and obtaining the internal total field of the complete scatterer through the network; and 5, calculating a total field or a scattering field at any position according to a moment method. According to the method, prediction of the scattering characteristics of the scatterer of which the shape and the electrical parameters are not completely known can be completed under the condition that only a very small amount of scattering field (observation / measurement) data is needed.

The invention relates to a PML-coupled three-dimensional magnetotelluric anisotropy parallel finite element forward modeling method. The method comprises the following steps: according to a continuity condition of an electromagnetic field and a dispersion relation of a plane wave in TE and TM modes, determining a non-reflection condition which needs to be met by a PML; determining a parameter form of the PML meeting stable absorption performance by utilizing a relationship between an incident field and a transmission field in the lossy medium; constructing an improved wide-frequency-band PML parameter tensor according to a non-reflection condition, a parameter form meeting stable absorption performance and preset characteristic parameters; and realizing finite element forward modeling under a preset multi-level parallel architecture by using the improved wide-frequency-band PML parameter tensor to obtain a finite element forward modeling result. The method is accurate, efficient and wide in application range.

The present invention proposes a method for solving the transmission characteristics of a cellular frequency selective surface. The implementation steps include: constructing a unit geometric model of the cellular frequency selective surface; performing mesh division on the unit geometric model; calculating the direction vector of the polarized plane wave in OXYZ; calculating the incident field at the excitation port in different modes; constructing a finite element matrix equation; performing matrix element substitution on the matrix equation; and obtaining the transmission characteristics of the cellular frequency selective surface. By using two vector edges of the excitation port and transforming the three-dimensional coordinate system into a three-dimensional local coordinate system, and calculating the wave numbers of the polarized plane wave in the three axial directions of the three-dimensional local coordinate system, the present invention calculates the incident field at the excitation port in different modes, avoiding the defect in the prior art that the incident field at the excitation port cannot be calculated in a coordinate system with two vector edges of a regular hexagon as the coordinate axes by using the finite element method, and achieving high-precision solution of the transmission characteristics of the cellular frequency selective surface.

The application relates to a three-dimensional magnetotelluric anisotropy parallel finite element forward method coupled with PML. The method comprises the following steps: determining a non-reflection condition required by PML according to the continuity condition of an electromagnetic field and the dispersion relation of a plane wave in TE and TM modes; determining the parameter form of the stable absorption performance of PML by using the relationship between the incident field and the transmission field in a lossy medium; constructing an improved wide-band PML parameter tensor according to the non-reflection condition, the parameter form of the stable absorption performance and preset characteristic parameters; and realizing finite element forward by using the improved wide-band PML parameter tensor under a preset multi-level parallel architecture to obtain a finite element forward result. The method can be accurate, efficient and widely applicable.

The present application relates to a kind of information recovery methods based on scattering system, belong to spectral data processing technical field.The method is: the scattering characteristic of scattering system is calculated;Using the scattering characteristic calculated, establish scattering signal self-excitation amplification mechanism;On the scattering signal self-excitation amplification mechanism, incident light field time domain, space domain, frequency domain coding and trend decoding, wave analysis, to nearly completely recover scattering information;Using negative correlation statistical operation obtains the accurate scattering information of high noise scattering system.The present application is amplified by the scattering signal of special self-excitation method, based on light field composite coding and scattering information trend analysis, accurately judges input field information;By introducing negative correlation operation, can nearly completely recover incident field information, realize the nearly complete evaluation of the scattering characteristic of extremely high noise system.The present application promotes the progress of imaging technology not limited by the thickness of scattering medium, further promotes the development of realizing human clinical high-resolution optical reflection, transmission imaging.

According to the method, a surface gravity wave and inner interface wave velocity potential field is analyzed into a product form of a vertical characteristic item and a horizontal diffraction field, and dimensionality reduction solution of a three-dimensional wave problem is realized; a vertical characteristic function orthogonal system meeting free liquid level, seabed boundary and interface coupling conditions is constructed, horizontal diffraction potential is decomposed into an incident field, a local column and an adjacent column scattering effect, and a Bessel function addition theorem is applied to construct a closed linear equation set of a multi-column interference field; establishing an extended dispersion equation containing density spring layer parameters, and revealing a modulation rule of layered strength on complex wave propagation characteristics; and finally, through tensor product coupling of a vertical mode and a horizontal diffraction field, constructing a full-three-dimensional diffraction velocity potential analytical solution, synthesizing a cross-layer pressure field integral by adopting a domain decomposition technology, and establishing a multi-column array generalized wave excitation force forecasting model. According to the method, efficient analytical calculation of the wave load of the multi-column system in the layered fluid is innovatively achieved.

The application discloses a high-power phase reconfigurable intelligent reflecting surface which is composed of array elements with the same structure; the array element comprises a receiving / transmitting unit, a coupling structure and a phase modulation circuit; the receiving / transmitting unit, the coupling structure and the phase modulation circuit are sequentially arranged to form a laminated structure; the receiving / transmitting unit is used for converting a free space electromagnetic wave into an electric field on the unit or converting a field from the coupling structure into a free space electromagnetic wave and radiating; the coupling structure converts the electric field into a guided wave which is transmitted to the phase modulation circuit, and converts a guided wave from the phase modulation circuit into an electric field on the receiving / transmitting unit; and the phase modulation circuit uniquely determines a shift operation of the guided wave according to an applied direct current voltage to add a specific additional phase. While realizing 360-degree phase control, the application has higher power capacity, and is expected to be widely applied in a high-power incident scene of the intelligent reflecting surface.

The invention relates to the technical field of film coating optics, in particular to a compensation method for transverse displacement and phase drift of a multilayer film surface, and the method specifically comprises the steps: S1, determining a corresponding spatial frequency according to an incident field of incident light at an incident position x, and calculating a reflection coefficient corresponding to the spatial frequency through a scattering matrix; s2, according to the phase corresponding to the reflection coefficient, transverse displacement and phase drift generated on the surface of the multi-layer film when the incident light is reflected in the multi-layer film are obtained; and S3, substituting the incident field, the reflection coefficient, the lateral displacement and the phase drift into the proposed compensation model to obtain a reflection field. According to the method, homeomorphic Fourier transform and a plane wave angular spectrum theory are used for deducing a compensation model of transverse displacement and phase drift of reflection rays of geometric rays on the top surface of the multilayer film, the calculation precision is effectively improved, and the calculation complexity is obviously lower than that of a traditional plane wave angular spectrum method adopting strict Fourier transform; and no obvious difference exists in calculation results.

The invention relates to the technical field of electromagnetic analysis, and discloses a ship double-station RCS calculation method, device and equipment and a storage medium, and the method comprises the steps: calculating a dielectric constant based on ship material parameters and sea surface physical parameters; based on the spatial position coordinates of the transmitter and the receiver, the propagation direction unit vectors of the incident wave and the received wave are calculated; the incident field amplitude is calculated based on the incident wave propagation direction unit vector; reflection analysis is carried out based on the ship-sea reflection path, a ship-sea path reflection vector function is obtained, and a ship-sea path reflection field amplitude is obtained through calculation in combination with a received wave propagation direction unit vector; calculating first station RCS data based on the incident field amplitude and the ship-sea path reflection field amplitude; replacing the ship-sea reflection path with a ship reflection path, and calculating to obtain second station RCS data; according to the method, the ship reflection path and the ship-sea reflection path are subjected to reflection analysis, so that more accurate RCS calculation is realized, and support is provided for ship detection in a complex ocean scene.

The invention discloses a method for generating a Skyrmion tube and an array thereof through tight focusing. The method comprises the following steps: constructing the Skyrmion tube or the Skyrmion tube array in a focal field in advance; the method comprises the following steps: slicing a pre-constructed focal field along an optical axis direction, and obtaining incident field distribution on an objective lens aperture surface corresponding to a slice through a tight focusing inverse operation process; coherently superposing the incident fields corresponding to all the slices to obtain total incident field distribution; and carrying out tight focusing on the total incident field by using an objective lens to obtain complex amplitude of a focal field, observing intensity and topological state distribution of the focal field in a three-dimensional space of a focusing area, and optimizing intervals between slices to obtain a tight focusing field with the skyrmion tubes or the skyrmion tube array. According to the method, the Skyrmion tube or the Skyrmion tube array is constructed in the focal field in advance, the focal field with the preset topological characteristic is obtained, and the method provided by the invention has certain universality.

The application discloses a fast calculation method and device for scattered electromagnetic field based on random matrix approximation, and belongs to the field of fast modeling of scattered field. The method comprises the following steps: precalculating an incident field vector and a reciprocal incident field vector; generating a Gaussian random matrix matched with the column number of a to-be-determined scattered response matrix; performing linear superposition on the incident field vector to obtain a synthetic incident field vector, and constructing a random projection matrix according to the scattered field vector of an equivalent current vector at a receiving point; performing linear superposition on the reciprocal incident field vector to obtain a reciprocal synthetic incident field vector, and constructing a projection coefficient matrix according to the response of a reciprocal equivalent current vector at a transmitting source; and calculating a complete scattered response matrix based on the product of an orthogonal basis matrix and the projection coefficient matrix. In the application, a large-scale geophysical electromagnetic complex scene can be adapted, higher calculation precision and stable convergence are achieved, and the reconstruction of the complete scattered response matrix can be completed at a lower relative error level.

This invention relates to a microwave imaging method integrating Born iteration and compressed sensing, comprising: establishing a two-dimensional electromagnetic inverse scattering integral equation model, discretizing the imaging region, setting iteration and prior parameters, and initializing the contrast and total field as background values ​​and incident fields, respectively; based on the total field of the previous iteration, constructing linearized scattering equations for multiple incident angles, defining single-view inversion as an independent task, and integrating them into a multi-task set sharing sparse priors; employing the MT-BCS algorithm to jointly solve the observation equations using shared hyperparameters, and outputting the updated contrast distribution; solving the state equation based on the new contrast to complete the total field update; outputting the imaging result if the convergence condition or the maximum number of iterations is met; otherwise, continuing iteration. This invention applies joint sparsity constraints through a multi-task joint inference mechanism, mining the geometric structure consistency of multi-view data, and overcoming the shortcomings of traditional single-task methods such as low signal-to-noise ratio, low reconstruction accuracy when measurement data is limited, and severe artifacts.

The application belongs to the technical field of electromagnetic calculation, and provides a group target electromagnetic scattering coupling modeling method based on a vector spherical wave function, first, a transmission matrix of each target is constructed, and a translation matrix between any two targets and a rotation matrix of each target are calculated; then, an initial excitation is set, and an initial incident field mode coefficient vector of each target under its local coordinate system is calculated; again, taking the initial incident field mode coefficient vector of each target as an initial value, the transmission matrix of each target, the rotation matrix of each target and the translation matrix between any two targets are used for group target coupling iteration solving, so as to obtain a scattering field mode coefficient vector of the group target; finally, the scattering field mode coefficient of the group target is used, combined with the vector spherical wave function, to construct a group target scattering field, and a radar scattering cross section of the group target is calculated according to the incident field and the group target scattering field, so as to realize group target electromagnetic scattering coupling modeling, and excellent accuracy and effectiveness are achieved.

The invention discloses an electromagnetic near-field scattering characteristic modeling calculation method based on half-space target source reconstruction and electronic equipment. The method comprises the following steps: modeling the ground into an infinite PEC, and constructing a surrounding surface for a target scatterer on the ground and a ground area in contact with the target scatterer; calculating an incident field of the incident wave on the surrounding surface, and solving equivalent electromagnetic current distribution on the surrounding surface by taking the incident field as an excitation source; removing a target scatterer in the surrounding surface, and performing integration on the equivalent electromagnetic current distribution by using a half-space green function to obtain a part of scattered field at the observation position; and calculating a background field of the observation position when only the incident field is incident on the infinite ideal electric conductor ground, and adding the background field and a part of the scattered field to obtain a total electromagnetic field of the observation point. Half-space target source reconstruction is carried out based on the Huygens equivalence principle, the model complexity is greatly reduced, the operation efficiency is remarkably improved, the problem of ground truncation is solved, and meanwhile, the method is suitable for far-field and near-field scenes.

The invention discloses an electromagnetic inverse scattering imaging method of a diffusion model based on multi-modal fusion features. The method comprises the following steps of: 1, delimiting a region of interest in a specific imaging environment, and arranging a transmitting antenna and a receiving antenna array at the periphery of the region of interest; collecting scattering field data of a to-be-tested scatterer in a free space, and constructing an input and output sample pair of the model in combination with incident field information and a corresponding medium parameter distribution truth value; 2, inputting the multi-modal condition data in the training sample pair into a corresponding feature extraction network for coding, and performing adaptive fusion through a cross-modal attention mechanism to generate fusion features; 3, constructing a diffusion model taking fusion features as conditions; and noise is added to the true value of the medium parameter through a forward diffusion process, and in a reverse denoising process, a denoising neural network is guided by using fusion features to predict noise, and a medium parameter distribution image of the region of interest is reconstructed step by step. The stability and generalization performance are remarkably improved.

The invention discloses a reverse scattering microwave imaging method based on an unconventional incident field. The microwave imaging system collects scattered field data of a target scatterer in a random irradiation mode and processes the scattered field data to obtain a preliminary imaging result; further determining a target area, performing system modulation to form a focusing incident field, and dividing the target area into a plurality of sub-areas according to the focusing incident field and the geometric center position of the initial imaging result of the target scatterer; adjusting the focus point to the center of each sub-region in sequence by adjusting the phase difference of the antenna, and acquiring scattered field data of the target scatterer in different sub-regions; and then quantitative inversion is carried out to obtain the numerical value and spatial distribution of the dielectric constant of the target scatterer, so that a target scatterer image is constructed. According to the method, the scattering effect of a specific area can be enhanced, the multiple scattering effects of other areas can be inhibited, the nonlinearity of the inverse scattering problem is reduced, the imaging precision is improved, and the method has huge application potential in multiple fields of medical imaging, industrial detection, geological exploration and the like.

The utility model discloses additive manufacturing equipment and a multifunctional light path system thereof, the multifunctional light path system comprises a laser, a collimating lens, a galvanometer unit, a field lens, a shaping lens and a driving mechanism, laser emitted by the laser enters the collimating lens, enters the field lens under the action of the collimating lens and the galvanometer unit in sequence, enters a working plane through the field lens, and then enters the working plane through the shaping lens; the shaping lens is arranged on the driving mechanism and moves under the driving of the driving mechanism, so that when the shaping lens moves to a light path between the collimating lens and the galvanometer unit, the shaping lens shapes laser entering the galvanometer unit to obtain an annular light spot; and when the shaping lens moves to be far away from the light path between the collimating lens and the galvanometer unit, the laser entering the galvanometer unit directly enters the field lens to obtain a Gaussian spot. According to the utility model, flexible switching between Gaussian light spots and annular light spots can be realized, details on the surface of a workpiece can be printed by using the Gaussian light spots with small light spot sizes, and large filling entities can be printed by using the annular light spots with large light spot sizes, so that the forming precision and efficiency are ensured.

A permittivity sensor for determining a map of a distribution of a permittivity of a material of an object in a scene is provided, the permittivity sensor comprising an input interface, a hardware processor, and an output interface. The input interface is configured to accept an apodized measurement of a propagation of a known incident field through the scene and scattered by a material of an object in the scene. The hardware processor is configured to solve a multivariate minimization problem for an unknown phase of the apodized measurement and an unknown map of a permittivity of the material of the object by minimizing a difference between a nonlinear function of the known incident field and the unknown map and a product of a known magnitude and the unknown phase of the apodized measurement. Further, the output interface is configured to present the permittivity of the material of the object provided by a solution of the multivariate minimization problem.

The application discloses a kind of dynamic aberration calculation method and laminated microlens array scanning system, the method includes the following steps: step S1: determine the maximum incident field of view of unit scanning structure in laminated microlens array scanning system;Step S2: calculate the wave aberration value of rotation symmetry or zero relative displacement unit scanning structure;Step S3: calculate the aberration field offset vector of non-rotation symmetry unit scanning structure that produces relative displacement;Step S4: calculate the wave aberration value of different scanning field or relative displacement unit scanning structure.This application has adopted the vector wave aberration model of non-rotation symmetry optical system, can accurately characterize the wave aberration of laminated microlens array scanning system in scanning process, using the calculation method, the aberration of each kind of surface of multiple optical surfaces of unit scanning structure arbitrary scanning field can be conveniently completed, to effectively help designer to regulate and control the aberration distribution of system, help to eliminate the dynamic aberration of system.

The invention provides a high-order CM24-Debye electromagnetic scattering calculation method for SAR (Synthetic Aperture Radar) image data generation, and relates to the technical field of electrical digital data processing, the method comprises the following steps: S1, under a CM24 high-order difference framework, constructing an auxiliary differential equation updating model of a Debye dispersion earth surface medium, and obtaining a main calculation area of the CM24 electromagnetic scattering model containing the Debye dispersion earth surface and the target body above the Debye dispersion earth surface. According to the method, an auxiliary differential equation updating model of a Debye dispersive medium is constructed under a CM24 high-order difference framework, so that high-order consistent calculation of dispersion earth surface electromagnetic response is realized; in a rough earth surface and a target scattering model above the rough earth surface, a discrete plane wave and a conical wave are combined at a connection boundary to load a loading field, so that the numerical dispersion of an incident wave is consistent with a main computational grid, and the edge diffraction influence caused by a limited truncation rough surface is reduced; and meanwhile, a complete matching layer absorption boundary based on a matrix index method is constructed, so that the absorption layer update is synchronized with the time step of the main calculation area.

The application discloses a terahertz isolator based on a time barrier metasurface, which is arranged on a substrate, and x and y polarizers are arranged on two sides of the substrate respectively, and the metasurface structure unit is arranged on one side of the substrate close to the y polarizer and comprises a metal rod, a first open resonant ring, a second open resonant ring, a third open resonant ring, a fourth open resonant ring, a first semiconductor structure and a second semiconductor structure. In the transient polarization conversion, the coherent destructive state of the two pairs of resonance modes is broken by the phase offset caused by the time barrier, so that the terahertz energy is radiated, and the coherent destructive state in the other direction is protected by the incident field, and the effect of the time loss barrier is invalid, thereby realizing one-way terahertz transmission.

The present invention belongs to the technical field of laser processing, and particularly relates to a shaping spot correction method for a laser processing system, a laser processing system, a laser processing method, and a correction model. The shaping spot correction method includes: obtaining an ideal Gaussian beam model G0; obtaining a transfer function T through the optical model of a beam shaper; calculating the beam function G0*T in front of an incident field lens; obtaining a transfer function F(x,y) through the optical model of the field lens; solving a correction function δ(x,y) through G0*T*F(x,y)*δ(x,y)=H0, where H0 is an ideal shaping spot distribution function, and * represents convolution; obtaining a grayscale image corresponding to the correction function δ(x,y), and inputting the grayscale image into a phase programmable device to correct the shaping spot scanned to a position (x,y) in the field lens area. The phase programmable device of the present invention can correct the spot at a certain position in the field lens area when the galvanometer scans to that position, so as to obtain an ideal and uniform shaping spot, and can achieve an ideal shaping spot throughout the entire area of the field lens.

Embodiments of the present disclosure provide a path loss determination method and apparatus, a storage medium, and an electronic device. The method comprises: determining a superimposed field image of a target grid scene on the basis of a first image, a second image, and an incident field image of the target grid scene, wherein the first image is used for indicating the position of a first object in the target grid scene, and the second image is used for indicating the position of a second object in the target grid scene; determining a first loss function on the basis of the incident field image and the superimposed field image, and determining a second loss function on the basis of the superimposed field image and drive test data of the target grid scene; determining a target loss function on the basis of the first loss function and the second loss function; and training a neural network model on the basis of the target loss function, so as to determine the path loss of the target grid scene by means of the trained neural network model. The method can solve the problem in the prior art that path loss estimation methods cannot take both accuracy and calculation efficiency into account.

The application discloses a low-complexity microwave device gas breakdown threshold transient efficient prediction method and system, which comprises the following steps: adopting an arbitrary high-order derivative time difference format, converting a set of ordinary differential equations of electron concentration into a set of algebraic equations, and solving the electron concentration; comprehensively considering the set of electron concentration equations and the first derivative and the second derivative thereof, and designing a breakdown judgment condition; repeatedly solving the electron concentration by the electron concentration solving step, judging according to the breakdown judgment condition, and based on the judgment result, updating the incident field amplitude of the upper limit or the lower limit by using the dichotomy, and converting the power amplitude to obtain the port incident power at the breakdown time. The application effectively solves the problem of low calculation efficiency of large-scale calculation faced by the steady-state method and the traditional transient method in the process of predicting the microwave device gas breakdown threshold, and finally realizes the efficient prediction of the low-pressure gas breakdown threshold of the microwave device.

The invention discloses a ground penetrating radar imaging method and system, relates to the technical field of ground penetrating radars, and solves the problem that complex electromagnetic characteristics of an underground detection domain are difficult to accurately represent in the traditional technology. According to the method, the equivalent dielectric constant is calculated, so that the problem of phase distortion caused by the traditional homogeneous medium hypothesis in the underground detection of the non-homogeneous medium is solved, the electromagnetic waves can still keep the accurate expression of the propagation path in the non-homogeneous medium, and the accurate characterization of the complex electromagnetic characteristics of the underground detection domain is realized; meanwhile, by detecting the vertical incidence hypothesis of the electromagnetic wave signal, the electromagnetic wave propagation path can be simplified, a non-uniform medium incidence field which is difficult to analyze and calculate is simplified into an equivalent uniform medium incidence field which can be analyzed and expressed, and the calculation complexity of an inversion reflectivity function is reduced.

The application provides an endoscope objective lens, and relates to the technical field of medical devices, which comprises, from the object side to the image side, a first spherical lens with negative optical power, a second spherical lens with positive optical power, a third spherical lens with negative optical power, a fourth spherical lens with positive optical power, a fifth spherical lens with positive optical power, a filter and a protective glass; the incident surface of the first spherical lens towards the object side comprises a plurality of different coating areas, the coating areas have different filter films, and the field angles of the plurality of coating areas are different. Through the shape, optical power and related parameter settings of each spherical lens, the endoscope objective lens has the advantages of a large field angle, miniaturization and a large depth of field, and through the partition coating, the transmittance curve and the reflectivity curve caused by the change of the incident field angle are reduced, the light of the cut-off laser band is blocked, the anti-laser effect of the coating is ensured, and under the condition of no laser, the color deviation during the imaging of the large field angle is eliminated, and the image quality is improved.

This application provides a method and system for measuring the dielectric constant of a material. The method includes: acquiring the incident field distribution of a transmitting antenna on a reference plane in the absence of a material sample; placing the material sample to be tested between the transmitting antenna and the receiving probe, measuring the transmission coefficient in the absence of a material sample and in the presence of a material sample, and processing the transmission coefficient to obtain a measured normalized transmission coefficient; constructing a forward physical transmission model based on the incident field distribution, wherein the forward physical transmission model takes the geometric parameters and dielectric constant of the material sample to be tested as input and outputs a theoretical normalized transmission coefficient; and determining the dielectric constant of the material sample to be tested by adjusting the assumed value of the dielectric constant to make the theoretical normalized transmission coefficient approximate the measured normalized transmission coefficient.

A wide-field-of-view narrow-band light filtering device comprises a narrow-band light filter and a plurality of wide-field-of-view interference assemblies. The beam splitter prism is used for carrying out beam splitting treatment on input light and transmitting the input light to the two plane mirrors respectively; the two plane mirrors reflect the received light beams to the beam splitter prism so as to generate two interference light beams; by observing interference light spots output by the wide-view-field interference assembly, the position of the plane mirror in the wide-view-field interference assembly is adjusted, so that the intensity of signal light returned by an original path is reduced; the first-stage wide-field-of-view interference assembly receives laser radar echo light beams transmitted through the narrow-band optical filter, and the front and rear adjacent wide-field-of-view interference assemblies receive signal light output by the upper-stage wide-field-of-view interference assembly through beam splitting prisms in the front and rear adjacent wide-field-of-view interference assemblies. According to the invention, ultra-narrow band filtering in a large incident field of view can be realized, so that background light interference is suppressed while high transmittance of effective signals is ensured, and the purpose of improving the detection signal-to-noise ratio is achieved.

The present invention discloses a diffraction phased array antenna based on space feeding. The diffraction phased array antenna includes a space feed source and a radiation panel. The space feed source and the radiation panel are arranged in parallel and spaced apart. The geometric centers of the space feed source and the radiation panel are at the same height, and the space feed source and the radiation panel are arranged in close proximity. The radiation panel is a planar aperture formed by a periodic uniform or non-uniform arrangement of multiple reconfigurable artificial surface units. The electromagnetic waves radiated by the space feed source propagate through free space and are incident on the radiation panel. The multiple reconfigurable artificial surface units independently perform phase compensation on the electromagnetic waves incident on themselves in the incident field, thereby obtaining a target diffraction phased array. The present invention adopts a space feed source, and an aspheric wave field is incident on the radiation panel. With the help of the phase reconfigurability of the artificial surface, the incident electromagnetic wave is phase compensated. While improving the aperture efficiency, the fluctuation of the gain of different directional beams is reduced, thereby achieving a larger angular scanning range.