51 results about "Field pattern" patented technology

The invention discloses a phase-free antenna measurement method, a phase-free antenna measurement system and a storage medium. The phase-free antenna measurement method comprises the following steps: constructing a measurement system comprising an antenna to be measured, a measurement probe, a fixed auxiliary reference antenna and software defined radio; the probe is controlled to move and sample on the scanning plane, and the SDR synchronously collects receiving signals of the probe and the reference antenna; based on the frequency domain transformation result of the two paths of signals, the radiation field amplitude of each sampling point and the relative phase relative to the reference antenna are directly calculated through non-iterative operation, so that complete complex electric field distribution on the scanning plane is reconstructed; and finally, obtaining a far-field directional diagram through near-field-far-field transformation. The fixed reference antenna is introduced to serve as a phase reference, synchronous acquisition and direct calculation are achieved in combination with the SDR, the antenna radiation field can be rapidly and accurately recovered without direct phase measurement or complex iteration in the single scanning plane and single scanning process, and the method has the advantages of being simple in system, high in measurement efficiency and high in signal drift resistance.

The invention provides an antenna field pattern visual measurement method, device, equipment and medium, and relates to the technical field of electromagnetic field measurement, and the method comprises the steps: constructing a visual model of an antenna according to the geographic coordinate, the measurement radius and the antenna height of the antenna; determining a sampling track on the visual model according to the measurement parameters of the antenna; mapping the sampling track into a geographic track according to a preset track mapping rule; according to the geographical trajectory, generating a route file which can be identified by the unmanned aerial vehicle, so as to control the unmanned aerial vehicle to collect electromagnetic field intensity data along the geographical trajectory; and carrying out combination and image drawing on the electromagnetic field intensity data and the measurement parameters to generate an antenna field pattern image. According to the technical scheme of the embodiment of the invention, the problems of poor visualization effect and low planning operation efficiency can be solved.

The invention provides a semiconductor laser element with improved service life. This semiconductor laser element is provided with: a first semiconductor layer which is a group III-V compound semiconductor layer containing at least As as a group V element; a second semiconductor layer on the first conductive side, which is a group III-V compound semiconductor layer containing at least P as a group V element, and which is disposed on the first semiconductor layer; a second conductive-side third semiconductor layer disposed on the second semiconductor layer; an active layer disposed between the second semiconductor layer and the third semiconductor layer; a window structure formed across the third semiconductor layer, the active layer, the second semiconductor layer, and the first semiconductor layer; a defect layer having a group III element of the first semiconductor layer and a group III element of the second semiconductor layer between the first semiconductor layer and the second semiconductor layer and including a defect in a region formed in the window structure; and an end surface that includes a defect layer that does not overlap the near-field pattern of the laser light on the end surface, or that overlaps only at the edge of the near-field pattern on the end surface, and that emits the laser light.

This invention discloses a method for analyzing the electrical performance range of an antenna radome based on interpolation. The method includes randomly generating multiple sets of thickness error and relative permittivity error distribution values ​​within the radome's thickness error range and relative permittivity error range; plotting the far-field radiation pattern of the antenna after adding the radome; extracting the variation range of electrical performance indicators from the pattern; discretizing the incident angle, polarization angle, thickness, and relative permittivity at various points on the radome; and calculating the transmission coefficient T of the main polarization component based on the discrete points. M Extract T M The amplitude and phase variation ranges are used to obtain T by interpolation. M In the sector-shaped interval formed in the complex domain, the sector-shaped interval is divided into polygonal intervals. The polygonal intervals are added together to calculate the range of changes in the far-field radiation pattern of the radome. The range of changes in the electrical performance index is extracted. It is determined whether the electrical performance index of the radome meets the preset requirements. If it does, the process ends. Otherwise, the number of segments in the sector arc is modified until the range of changes in the electrical performance index that meets the preset requirements is obtained.

The present application provides an antenna device, which includes a housing assembly, a first waveguide assembly and a second waveguide assembly. The interior of the housing assembly defines a cavity, and a slot is formed through the first side of the housing assembly. At least a portion of the first waveguide assembly is located in the cavity and is connected to the first side of the housing assembly. The projection of the first waveguide assembly on the first side of the housing assembly is symmetrically located on both sides of the slot. The second waveguide assembly is located outside the housing assembly, near the first side and connected to the slot. The second waveguide assembly is adapted to transmit an antenna signal through the slot to the cavity via the first waveguide assembly. The antenna signal resonates in the cavity and is radiated outward from the second side of the cavity relative to the first side. The antenna device of the present application has good signal transmission effect and stable and symmetric field pattern distribution.

The invention discloses a bidirectional wave beam scanning leaky-wave antenna based on a trapezoidal sliding symmetrical structure. The bidirectional wave beam scanning leaky-wave antenna comprises an input end transition part used for feeding, an electromagnetic field modulation radiation array and an output end transition part used for matching absorption, a second rectangular waveguide cavity is arranged in the electromagnetic field modulation radiation array, cascaded trapezoidal metal resonant cavities in sliding symmetry are introduced into the inner sides of the upper wall and the lower wall of the second rectangular waveguide cavity, and the trapezoidal metal resonant cavities in sliding symmetry are the same in geometric size and staggered by a half structural period in the propagation direction; a radiation slot array is arranged on the upper wall of the electromagnetic field modulation radiation array to form a composite energy coupling area for electromagnetic field modulation; the input end transition part and the output end transition part are of a symmetrical structure, and the first rectangular waveguide cavity close to the electromagnetic field modulation radiation array is provided with a gradual change impedance matching section, so that smooth impedance conversion and field pattern matching are realized; transmission of a fast wave mode and a slow wave mode can be supported at the same time.

The application relates to a kind of multi-rotor unmanned aerial vehicle-based antenna far field pattern near distance measurement system and method, including multi-rotor unmanned aerial vehicle, signal transceiver unit, data acquisition equipment, photoelectric converter;Signal transceiver unit includes signal transceiver module, electro-optical converter, receiving antenna and wireless transmission module;The application is centered on the antenna to be measured, controls multi-rotor unmanned aerial vehicle to carry out horizontal semicircle flight around the antenna to be measured, and signal transceiver module emits an electric signal every N degrees on azimuth angle θ;Electric signal is converted into optical signal, is transmitted to photoelectric converter through optical fiber and is converted into electric signal again and is emitted through the antenna to be measured, and receiving antenna receives the electric signal, carries out near far field conversion processing, obtains the far field pattern of the antenna to be measured.The application can obtain the accurate amplitude and phase information of the antenna to be measured because the signal received by receiving antenna and the transmitting signal have the same source, form coherence.

A semiconductor laser element comprises a first semiconductor layer, which is a III-V composite semiconductor layer containing at least As; a second semiconductor layer, located above the first semiconductor layer, which is a III-V composite semiconductor layer containing at least P; a third semiconductor layer, located above the second semiconductor layer; an active layer on the second semiconductor layer; a window structure formed across the first to third semiconductor layers and the active layer; a defect layer having a defect located in a region where the window structure is formed and between the first and second semiconductor layers, and containing one group III element from each of the first and second semiconductor layers; and an end surface that emits laser light and contains the defect layer.The defect layer does not overlap with a near-field pattern of laser light at the final surface or overlaps only with an end part of the near-field pattern.

This invention proposes a method and apparatus for synthesizing array radar radiation patterns using space-time joint modulation. The method includes: determining initial values ​​of the array radar element excitation coefficients; acquiring the array far-field radiation pattern under the influence of the initial values ​​of the element excitation coefficients; dividing the array far-field radiation pattern into main lobe and side lobe regions based on its characteristics; setting the random modulation phase of the main lobe region to zero, maintaining the same main lobe phase across different pulses, while modulating the phase of the side lobe region regularly or randomly, while keeping the array far-field radiation pattern amplitude constant, thus obtaining array radiation patterns with different phase characteristics under multiple pulses; performing Fourier transforms on the array radiation patterns under different pulses to obtain the space-time two-dimensional element excitation coefficients; and applying the space-time two-dimensional element excitation coefficients to the array radar system to synthesize the array radar radiation pattern after space-time joint modulation. This invention significantly improves the array radar's resistance to sidelobe clutter and interference.

The invention discloses an antenna feed amplitude-phase quantification method and system based on an improved non-dominated genetic algorithm, and belongs to the technical field of phased-array antennas. The method comprises the following steps: firstly, establishing a far-field pattern calculation model of a phased array, and then optimizing the continuous phase and continuous amplitude of feed in two stages by using an improved non-dominated genetic algorithm: in the first stage, obtaining an optimal phase quantization operation by taking the minimization of a beam pointing error as a target; in the second stage, on the basis of a phase optimization result, the optimal amplitude quantization operation is obtained by taking the maximum sidelobe level of the minimized beam as a target; and finally, a control signal for directly driving the digital phase shifter and the attenuator is generated. According to the method, the amplitude-phase quantization error is systematically controlled by introducing the random quantization interval threshold and error covariance matching technology, the beam pointing precision and the side lobe suppression performance are effectively coordinated by combining elite reservation and adaptive genetic manipulation, and the comprehensive electrical performance of the antenna under the influence of the quantization error is remarkably improved.

The application discloses a target mode vortex wave generation method of a time modulation array, and comprises the following steps: constructing a rotationally symmetric time modulation array model; dividing a circular array into P sectors and H rings on average, and distributing unit groups in each ring to form a subarray; each sector is uniformly fed through a group of time modulation circuits; adopting a double-path high-speed radio frequency switch and a pi / 2 fixed phase shifter to construct a quadrature signal time modulation circuit to suppress non-target harmonics; based on a far-field pattern expression of the time modulation array, switch-on time and switch-on time of the switch are designed; by simultaneously feeding different sector antenna units and controlling switch timing of different sectors, a high-purity vortex electromagnetic wave with a mode number of l is generated. The target mode vortex electromagnetic wave generated by the method has the characteristics of high feeding efficiency and high mode purity under the same main lobe gain.

The invention discloses a chip antenna phase center alignment method, and belongs to the technical field of chip antennae, and the method comprises the steps: carrying out the pre-scanning of a phase pattern of a chip antenna through a scanning frame, carrying out the judgment of the position deviation of a phase center and an actual scanning center through the obtained phase pattern data, and adjusting the position of a scanning circle center, before testing, the position of the phase center of the antenna is determined through simulation, and a coordinate system is established by referring to the phase center obtained through simulation during testing. According to the center alignment method, the position of an actual phase center is confirmed by carrying out a phase pattern pre-scanning technology, so that the accuracy of data, such as a far-field pattern and spherical near-field amplitude phase data, obtained through spherical scanning is ensured; the problem that the phase center of the chip antenna cannot be confirmed through a simple geometric position is solved, and compared with an existing testing process, the problem that the phase center of the chip antenna is difficult to calibrate due to factors such as the structure and the size of the chip antenna is solved.

The invention provides a far-field pattern test method and system, a mechanical arm is rotated according to a preset control instruction, the in-place time of the mechanical arm is fed back in real time, a to-be-tested phased-array antenna is installed on the mechanical arm, and the preset control instruction is configured according to a preset stepping amplitude and a preset rotation angle; in response to the received in-place time, sending an enabling trigger signal according to a synchronous calibration signal from the vector network analyzer so as to enable the vector network analyzer to test each point location according to the beam direction to determine the amplitude and phase trajectory data of each point location; and performing data recovery according to the amplitude and phase trajectory data of each point location, determining directional diagram data pointed by each beam, and summarizing the directional diagram data pointed by each beam under each frequency point to obtain a test result of the phased-array antenna. The automatic test process is adopted in the whole process, the test cost is reduced, the test efficiency is also improved, and meanwhile, the test precision is also improved through a trigger signal synchronization mechanism.

This invention relates to the field of digital array antenna testing technology and discloses a rapid desktop testing method for the receiving pattern of a digital array antenna. The method includes: initializing and synchronizing a multi-channel far-field simulation device and a beamforming processor for the digital array antenna; ensuring that each transmit channel of the multi-channel far-field simulation device is phase-consistent with each receive channel of the beamforming processor through calibration and balancing; establishing a set of scanning angles based on relevant information of the digital array antenna; the multi-channel far-field simulation device generating signals corresponding to the scanning angles and injecting them into the beamforming processor; the beamforming processor extracting information for each corresponding scanning angle and transmitting it to a host computer, until all scanning angles have been traversed to obtain the far-field pattern of each beam, thus completing the entire testing process. This invention can simulate the input of a standard antenna at each incident angle under far-field conditions, enabling the testing and verification of the receiving pattern of the beamforming processor for the digital array antenna.

An optical projection device includes an emitter, which is configured to emit a beam of coherent light. An optical substrate is disposed in a path of the beam. A metasurface is disposed on the optical substrate and includes an array of diffractive structures configured to modulate a polarization of the light so as to project a far-field pattern of interleaved areas having different, respective degrees of polarization.

Light-emitting devices including solid-state light-emitting devices, light-emitting diodes (LEDs), and LED packages with reinforcement materials and related methods are disclosed. Reinforcement materials may include fibers and / or particles that are incorporated in various elements of light-emitting devices to provide improved mechanical strength, reduced differences in thermal expansion, improved adhesion between various device elements, modified optical characteristics such as modified far field patterns, and / or improved manufacturability. Reinforcement materials may be provided within support elements on which LED chips are mounted. In certain aspects, the support elements may be light-transmissive to light emitted by the LED chips. Reinforcement materials may also be provided in laminate films are that provided on support elements. Such laminate films may provide build-up structures that form cavities for the LED chip, or the laminate films may conformally cover the LED chips.

The invention discloses a low-pumping high-synchronization transmission-reflection terahertz holographic super-structure array which comprises a patterned metal layer, a response material layer and a substrate layer. The patterned metal layer comprises m * n patterned metal units with the same size, and each patterned metal unit comprises an annular metal hole and a Z-shaped structure arranged in the annular metal hole; phase distribution corresponding to the patterned metal layer is calculated by an improved GS algorithm and is realized by setting different rotation angles corresponding to the Z-shaped structure; the response material layer is arranged on the silicon layer below the patterned metal layer; and the substrate layer is arranged below the response material layer as a substrate, and the substrate layer is made of sapphire. According to the invention, low-pumping, high-modulation-speed, high-modulation-depth, wide-band and wide-range and transmission-reflection high-synchronization holographic imaging can be realized; and meanwhile, ultrafast energy regulation and control can be carried out on a holographic field pattern through pump light control.

The application discloses a two-dimensional directional diagram testing method adopting a planar near-field fast inversion method, and comprises the following steps: S1, a near-field testing system is built; S2, a control terminal of the testing system is used to control a testing radar, so that an active phased array antenna of the testing radar works in a receiving state and is directed to a direction to be tested; S3, a probe is made to perform array scanning according to a specified path; S4, the control terminal of the testing system is used to control a vector network tester, and testing data is automatically recorded; S5, according to the testing data collected by the vector network tester, two-dimensional directional diagram inversion calculation is performed, and a directional diagram inversion result of the beam pointing direction is obtained. The two jobs of near-field calibration and near-field directional diagram testing can be simultaneously completed in a near-field testing environment, the testing data obtained through the near-field directional diagram testing is used for near-field directional diagram inversion, and a directional diagram result of the active phased array antenna is derived, so that the testing efficiency of the active phased array is improved. Therefore, the method is suitable for popularization and application.

A Light Detection and Ranging (LIDAR) apparatus includes an optical aperture, an emitter array including emitter elements arranged and configured to output optical signals through respective sub-regions of the optical aperture to illuminate respective portions of a field of view, and an optical element in at least a portion of the optical path of the optical signals. The optical element is configured to divert a first subset of the optical signals away from the respective portions of the field of view without substantially altering a second subset of the optical signals. Related optical elements and methods of fabrication are also discussed.

The invention discloses a double-reflector antenna electromechanical coupling rapid analysis method and system, and aims to reconstruct a physical optical integral expression. Dispersing the reflecting surface into triangular grids, and performing linear fitting on amplitude and phase functions in each grid; an equivalent wave number / wavelength concept is introduced, a phase fitting error is analyzed, a differentiated grid processing strategy is put forward, a closed expression for calculating a far-field directional diagram is deduced through affine transformation and partial integration, and numerical integration is replaced by analytical calculation; and converting the structural deformation into an additional phase error, and integrating the additional phase error into a rapid calculation framework. The method breaks through the limitation of the traditional electromagnetic analysis on the grid size, greatly improves the electromechanical coupling analysis speed on the premise of guaranteeing the precision, and provides an efficient tool for the design and profile compensation of a high-frequency-band antenna.

The invention discloses a rapid optimization method, system and device for a square-aperture multimode horn and a medium, and relates to the technical field of antenna design, and the method comprises the steps: determining an initial structure parameter of a to-be-optimized square-aperture multimode horn through a mode ratio method according to a preset far-field pattern equalization level requirement; constructing a target function based on the return loss of the input port of the to-be-optimized square-aperture multimode horn and a preset weight corresponding to the equalization level of the far-field pattern; based on the initial structure parameters and the target function, rapidly calculating a target function value by using a pattern matching theory, and optimizing the initial structure parameters in combination with a genetic algorithm to obtain optimized structure parameters; and when the target square aperture multimode horn determined based on the optimized structure parameters meets a preset requirement, outputting the optimized structure parameters. According to the method, the convergence speed and precision of multimode horn design are improved, the design period is greatly shortened, and the design cost is reduced.

The invention belongs to the technical field of antenna testing, and discloses an antenna near-far field fast conversion method based on error matrix pre-compensation, which comprises the following steps: acquiring complex near field amplitude phase data of a to-be-tested antenna; constructing a transformation regular matrix between the near-field coefficient and the far-field coefficient; performing mode spectrum analysis to identify an invalid high-order mode causing matrix morbidity; constructing an adaptive error compensation matrix to selectively suppress an invalid mode; fusing the compensation matrix and the transformation regular matrix to generate a modified regular matrix with an optimized conditional number; solving a spherical wave expansion coefficient based on the correction matrix; and finally, calculating a far-field pattern and a gain parameter of the antenna. According to the method, the morbidity of the transformation matrix is inhibited from the source through a pre-compensation mechanism, and the stability of numerical solution and the precision and efficiency of far-field transformation are remarkably improved while the integrity of physical information is ensured.

The invention provides a coding metasurface and terahertz wave beam regulation and signal processing device, at least one metasurface structure unit, each metasurface structure unit comprises a silicon column, a polytetrafluoroethylene layer and a vanadium dioxide layer from top to bottom, the silicon column comprises two cross arms which are orthogonally arranged along the central axis of the polytetrafluoroethylene layer, and the two cross arms are arranged in parallel. End points of the cross arms located on the upper side and the lower side are connected with each other through extension arms, surrounding arms are arranged on the side edges of the cross arms located on the left side and the right side at intervals, a rectangular hollow area is formed in the cross position of the two cross arms, four phase states of 0 degree, 90 degrees, 180 degrees and 270 degrees are achieved, and by combining correlation of coding patterns and far-field directional diagrams under Fourier transform, the far-field directional diagrams are obtained. Signal processing is directly completed in a terahertz frequency band through dynamic convolution operation, in addition, a 2-bit coding metasurface is constructed to generate an OAM wave beam, and the detail capturing capability in the imaging process is further improved.

A high-efficiency phased array multi-beam test method for improving the precision of a sidelobe area comprises the following steps: step 1, for a to-be-tested antenna array, obtaining an array directional diagram; 2, testing the array directional diagram to obtain the array directional diagram; 3, calculating electric field distribution data of the nth array element; 4, electric field data of the array unit to be tested on the test radius r is decomposed into a linear combination of spherical harmonic waves with unknown coefficients, and a linear equation of a spherical wave expansion formula is obtained; 5, processing by adopting an eccentric sampling algorithm to generate a least square problem; 6, solving a least square problem by using a sparse optimization method; 7, reconstructing K spherical wave expansion coefficients in the linear equation; 8, reconstructing a far-field pattern of the antenna unit; step 9, acquiring a unit pattern of which the phase center is located at the geometric center of the array; and 10, calculating an array directional diagram. The method has the advantages of being short in measurement time and high in array directional diagram minor lobe precision.

The invention provides a multi-beam synthesis method and device based on a collaborative null generation strategy, and belongs to the technical field of antenna design. The method provided by the invention comprises the following steps: randomly generating a design index in a beam direction range, and constructing a mask matrix based on the design index; constructing a multi-beam comprehensive model, inputting the mask matrix into the multi-beam comprehensive model, and training the multi-beam comprehensive model to output amplitude excitation and phase excitation of each beam; constructing a target mask matrix according to beam performance indexes in an actual application scene; and inputting the target mask matrix into a trained multi-beam comprehensive model, outputting amplitude excitation and phase excitation of each array unit for different beams, loading the amplitude excitation and the phase excitation to a multi-beam phased array, and generating a multi-beam far-field directional diagram. The invention provides a multi-beam synthesis method and device based on a collaborative null generation strategy. The method and the device are used for reducing the loss of equivalent omnidirectional radiation power on the premise of effectively suppressing multi-beam interference.

The application discloses a bidirectional beam scanning leaky-wave antenna based on a trapezoidal slip symmetry structure, which comprises an input end transition part for feeding, an electromagnetic field modulation radiating array and an output end transition part for matching absorption which are sequentially connected; the electromagnetic field modulation radiating array is internally provided with a second rectangular waveguide cavity, a cascade of slip symmetry trapezoidal metal resonant cavities is introduced into the inner side of the upper and lower walls of the second rectangular waveguide cavity, the geometric sizes of the slip symmetry trapezoidal metal resonant cavities are the same and are staggered by half a structure period in the propagation direction; the upper wall of the electromagnetic field modulation radiating array is provided with a radiating slot array, thereby forming a composite energy coupling area for electromagnetic field modulation; the input end transition part and the output end transition part are symmetrical structures, and a gradual impedance matching section is arranged close to the first rectangular waveguide cavity of the electromagnetic field modulation radiating array, thereby realizing smooth impedance conversion and field pattern matching; and the bidirectional beam scanning leaky-wave antenna can simultaneously support the transmission of fast wave mode and slow wave mode.

The invention discloses an antenna far-field pattern acquisition method and system based on unmanned aerial vehicle near-field measurement, and the system can achieve the restoration of a phase through the amplitude data of two scanning planes, solves a problem that the phase can be obtained only through the wired connection of a vector network analyzer in the near-field measurement of an unmanned aerial vehicle antenna, and improves the measurement precision. And the complexity and the cost of the test system are greatly reduced. According to the method, a PSO algorithm and an RAF algorithm are combined, a good initial solution is obtained by using the global search capability of PSO, then the weight of each measurement equation is dynamically adjusted by using a reweighting mechanism of the RAF algorithm, forward propagation and adjoint propagation operators are designed, a physical propagation process is converted into an optimizable mathematical problem, and a non-convex SCAD gradient sparse regular term is introduced, so that the optimal solution is obtained. According to the method, spatial domain priori knowledge of field distribution is effectively introduced in an iterative reconstruction process, that is, sparse edge features of antenna field distribution are better maintained while noise is suppressed, so that a high-quality reconstruction result better conforming to physical reality is obtained.

The application belongs to the technical field of semiconductor photoelectric devices, and particularly relates to a semiconductor laser element with a strain-induced exciton response layer, which comprises, from bottom to top, a substrate, a lower confinement layer, a lower waveguide layer, an active layer, an upper waveguide layer, an electron blocking layer and an upper confinement layer, wherein the upper waveguide layer and the electron blocking layer are provided with the strain-induced exciton response layer; the strain-induced exciton response layer is one of KV3Sb5, WSe2, ReO3, RbV3Sb5, CsV3Sb5 and KSbO3 or a combination of two or more thereof; the strain-induced exciton response layer is created by applying a local strain to the interface between the active layer and the upper waveguide layer and / or the lower waveguide layer, creating a strain field, changing the electron anisotropy, eliminating the sub-bandgap emission state of the spectrum overlap of the strain-induced exciton response layer, inhibiting the mode jump in the vertical direction, generating a single-mode laser, obtaining a good FFP far-field pattern, enhancing the exciton response of the active layer, reducing the driving voltage and excitation threshold of the laser element, enhancing the confinement factor, and improving the optical power and slope efficiency of the laser element.

The mode field diameter acquisition device according to the present disclosure is a device for acquiring a mode field diameter of each spatial mode of an optical fiber having a core, through which a plurality of spatial modes can propagate, from a near field pattern, and includes a mode field diameter acquisition unit configured to acquire a mode field diameter of a freely-selected spatial mode using a near field pattern of the spatial mode, and a mathematical expression based on a variational expression of a propagation constant of the spatial mode.