Abstract: The present disclosure provides a dual-mode orbital angular momentum (OAM) convergence base cell array and metasurface preparation method. The base cell array includes 2n(2n?1) anisotropic cell structures and 2n isotropic cell structures. Each of the anisotropic cell structures includes a bottom ground layer, a dielectric substrate layer and a top pattern layer which are disposed in sequence from bottom to top, where each top pattern layer has an axisymmetric H-shaped structure. Each of the isotropic cell structures includes a bottom ground layer, a dielectric substrate layer and a top pattern layer which are disposed in sequence from bottom to top, where each top pattern layer has a square structure.

Abstract: An ultra-wideband electromagnetic band gap (EBG) structure includes multiple EBG units in an array. Each EBG unit includes a power plane, a dielectric substrate and a ground plane from top to bottom. The power plane includes a patch, a coupled complementary split ring resonator (C-CSRR) and a plurality of semi-improved Z-bridge structures. Each edge of the patch is provided with a semi-improved Z-bridge structure. The C-CSRR is provided within a ring formed by the semi-improved Z-bridge structures. The Z-bridge structure includes a first horizontal branch, a first vertical branch, a second horizontal branch and a second vertical branch connected in sequence. The second vertical branch is connected to the patch. First horizontal branches of adjacent EBG units are connected to each other. A circuit board including the aforementioned EBG structure is also provided.

Abstract: A broadband fifth-generation (5G) circularly polarized filtering antenna includes a reflecting plate, a first dielectric substrate, a second dielectric substrate, a third dielectric substrate, a fourth dielectric substrate, a feed line with a phase adjustment function print on one surface of the first dielectric substrate, a ground with a chair-like groove on an other surface of the first dielectric substrate, a first rectangular radiating unit, a second rectangular radiating unit, a first metal transmission strip group and a second metal transmission strip group.

Abstract: A broadband fifth-generation (5G) circularly polarized filtering antenna includes a reflecting plate, a first dielectric substrate, a second dielectric substrate, a third dielectric substrate, a fourth dielectric substrate, a feed line with a phase adjustment function print on one surface of the first dielectric substrate, a ground with a chair-like groove on an other surface of the first dielectric substrate, a first rectangular radiating unit, a second rectangular radiating unit, a first metal transmission strip group and a second metal transmission strip group.

Abstract: Provided is a miniaturized ultra-low frequency antenna, including upper layer positive and negative electrodes, middle layer positive and negative electrodes and lower layer positive and negative electrodes, and a polyvinylidene fluoride column. The polyvinylidene fluoride column is respectively connected with the upper layer positive and negative electrodes, the middle layer positive and negative electrodes and the lower layer positive and negative electrodes. The polyvinylidene fluoride column is coated with stress electromagnetic conversion material layers. The upper layer positive and negative electrodes, the middle layer positive and negative electrodes and the lower layer positive and negative electrodes drive the polyvinylidene fluoride column to generate a deflection force through a voltage, and the stress electromagnetic conversion material layers are prompted to radiate electromagnetic waves and radiate under an action of the deflection force.

Abstract: The present disclosure provides a 5th generation (5G) broadband dual-polarized base station antenna of a multimode resonance structure, including: a first resonance structure, a main radiating unit, a feed balun set, and a metal reflecting plate, where the feed balun set is disposed on the metal reflecting plate, the main radiating unit is disposed on a first feed balun and a second feed balun, and the first resonance structure is disposed on the main radiating unit; the main radiating unit includes a second resonance structure and a third resonance structure, the first resonance structure is configured to control a resonance point at a high frequency, and the third resonance structure is configured to control a resonance point at a low frequency; and the feed balun set is configured to provide a balance current for the main radiating unit and the first resonance structure.

Abstract: Bidirectional circularly polarized antenna element and bidirectional circularly polarized array antenna are provided, and comprising a dielectric substrate, a feeder, a radiation patch, a first plane, a second plane, a first coupling assembly and a second coupling assembly which are embedded in the surface of the dielectric substrate. The first plane and the second plane of the antenna element are kept at different heights, and compared with the solution that two planes at the same height can only generate linear polarization radiation in the prior art, the circular polarization radiation can be generated, which solves the problem of linear polarization mismatch. Furthermore, two coupling assemblies are introduced into two sides of the radiation patch to enable the coupling effect with the radiation patch, such that the frequency bandwidth of the circularly polarized antenna can be greatly improved without increasing the size of the antenna.

Abstract: Disclosed is a high-efficiency acoustic excitation low-frequency antenna driven by serial electrodes, including a plurality of electrode driving units for generating enhanced mechanical vibration waves based on voltage driving, a plurality of electrode isolation insulators positioned between every two electrode driving units to prevent short circuit between the electrode driving units, a mechanical-electromagnetic field conversion unit used for converting the enhanced mechanical vibration waves into enhanced electromagnetic field radiation and improving receiving sensitivity based on the enhanced electromagnetic field radiation, and electrode constraint structures used for constraining the electrode driving units so that the electrode driving units are located in the electrode constraint structures.

Abstract: The present disclosure provides a fire source detection method and device under the condition of a small sample size, and a storage medium, and belongs to the field of target detection and industrial deployment. The method includes the steps of acquiring fire source image data from an industrial site; constructing a fire source detection model; inputting the fire source image data to the fire source detection model, and analyzing the fire source image data via the fire source detection model to obtain a detection result, where the detection result includes a specific location, precision and type of a fire source. By means of the method, the problems of insufficient sample capacity and difficulty in training under the condition of a small sample size are solved, and different enhancement methods are used to greatly increase the number and quality of samples and improve the over-fitting ability of models.

Abstract: The present disclosure belongs to the technical field of OAM antennas, and provides a frequency re-configurable OAM antenna in S band and a frequency reconfiguration method. The OAM antenna includes a lower dielectric substrate and multiple array units. Each array unit includes a metal patch, an upper dielectric substrate, an outer loop, an inner loop, a coaxial feeder, four metal probes, and four diodes. In the present disclosure, bias states of all the diodes of each array unit are controlled by applying a voltage; when all the diodes are in forward bias states, the antenna works at a high frequency; and when all the diodes are in reverse bias states, the antenna works at a low frequency. The frequency re-configurable OAM antenna in S band in the present disclosure has features of frequency reconfiguration and two OAM radiation modes, and has a stable gain over a broadband.

Abstract: The present disclosure relates to a high-speed and low-power successive approximation register analog-to-digital converter (SAR ADC) and an analog-to-digital conversion method. Binary redundancy reassembly is performed to improve a digital-to-analog converter (DAC) capacitor array included in the SAR ADC such that the total number of capacitors included in a capacitor sub-array of the DAC capacitor array is greater than the number of precision bits of the SAR ADC, and the total number of unit capacitors included in all capacitors when the total number of capacitors included in the capacitor sub-array is greater than the number of precision bits of the SAR ADC is equal to the total number of unit capacitors included in all capacitors when the total number of capacitors included in the capacitor sub-array is equal to the number of precision bits of the SAR ADC.

Abstract: A broadband solar cell antenna includes a first solar cell layer, a first dielectric supporting layer, an antenna layer, a second dielectric supporting layer, and a second solar cell layer sequentially from top to bottom. The first and second solar cell layers are structurally identical; the first and second dielectric supporting layers are structurally identical; a monopole is a metal base copper-clad laminate in a shovel-shaped structure; a trumpet-shaped grounded coplanar waveguide (GCPW) feeding line is used; and a solar cell array forms a meta-surface structure. The broadband solar cell antenna has the features of broadband, miniaturization and low profile. The antenna layer is provided between the two solar cell layers. Solar cells on an upper surface and a back surface of the antenna can collect light in different angles. The antenna has desired radiation performance and can function as both an antenna and a solar cell.

Abstract: This disclosure provides a perovskite light-emitting diode with an adjustable light field, including a glass layer, an anode, a hole transport layer, an emission layer, an electron transport layer and a cathode in sequence from top to bottom. The electron transport layer is provided with a periodic nano-grating structure.

Abstract: Disclosed is a ceramic piezoelectric underwater detection and 5th generation (5G) mobile phone antenna, including: a ceramic cavity, a thin film, electrode feed holes and a coating, where the thin film is embedded inside the ceramic cavity; the electrode feed holes are drilled on both sides of the thin film at one end of a bottom of the ceramic cavity; the coating is coated outside the ceramic cavity for realizing omnidirectional radiation; the thin film drives the ceramic cavity to make the coating on an outer surface of the ceramic cavity generate radiation vibrations and generate electromagnetic wave radiation for communication and underwater detection.

Abstract: Disclosed is a multi-layer low-profile four-arm spiral antenna, including a metal grounding plate, and a top surface of the metal grounding plate is fixedly connected with three layers of cylindrical dielectric substrates; the three layers of dielectric substrates are coaxially arranged, and the three layers of dielectric substrates are coaxially arranged with the metal grounding plate, and a gap is set between two adjacent layers of dielectric substrates; four spiral metal strips with a same rotation direction are respectively arranged on each layer of dielectric substrate, the four spiral metal strips on each layer of dielectric substrate form spiral radial arms, and a phase difference of the four spiral metal strips on each layer of dielectric substrate is 90°; the corresponding spiral metal strips on the two adjacent layers of dielectric substrates are connected by connecting bridges, the connecting bridges are arranged in the gap.

Abstract: A reconfigurable intelligent metasurface with adjustable 3-bit dual-polarization phases may include a plurality of reconfigurable intelligent metasurface units with adjustable 3-bit dual-polarization phases. Each of the plurality of reconfigurable intelligent metasurface units may include: a first layer including four fan-shaped metal patches and four Y-shaped metal patches symmetrical about a center, a second layer being a feeding layer along the x-axis direction, a third layer being a feeding layer along the y-axis direction, and a fourth layer being a metal ground layer. By changing a voltage value at two ends of each of the varactors in an orthogonal polarization direction, the reconfigurable intelligent metasurface unit may be enabled to independently implement dual-polarization 3-bit phase modulation in two orthogonal polarization directions, thereby implementing decoupling in the orthogonal polarization directions.

Abstract: The present disclosure provides a dual-mode orbital angular momentum (OAM) convergence base cell array and metasurface preparation method. The base cell array includes 2n(2n-1) anisotropic cell structures and 2n isotropic cell structures. Each of the anisotropic cell structures includes a bottom ground layer, a dielectric substrate layer and a top pattern layer which are disposed in sequence from bottom to top, where each top pattern layer has an axisymmetric H-shaped structure. Each of the isotropic cell structures includes a bottom ground layer, a dielectric substrate layer and a top pattern layer which are disposed in sequence from bottom to top, where each top pattern layer has a square structure.

Abstract: A contextual visual-based synthetic-aperture radar (SAR) target detection method and apparatus, and a storage medium, belonging to the field of target detection is described. The method includes: obtaining an SAR image; and inputting the SAR image into a target detection model, and positioning and recognizing a target in the SAR image by using the target detection model, to obtain a detection result. In the present disclosure, a two-way multi-scale connection operation is enhanced through top-down and bottom-up attention, to guide learning of dynamic attention matrices and enhance feature interaction under different resolutions. The model can extract the multi-scale target feature information with higher accuracy, for bounding box regression and classification, to suppress interfering background information, thereby enhancing the visual expressiveness.

Abstract: The present disclosure provides a fire source detection method and device under the condition of a small sample size, and a storage medium, and belongs to the field of target detection and industrial deployment. The method includes the steps of acquiring fire source image data from an industrial site; constructing a fire source detection model; inputting the fire source image data to the fire source detection model, and analyzing the fire source image data via the fire source detection model to obtain a detection result, where the detection result includes a specific location, precision and type of a fire source. By means of the method, the problems of insufficient sample capacity and difficulty in training under the condition of a small sample size are solved, and different enhancement methods are used to greatly increase the number and quality of samples and improve the over-fitting ability of models.

Abstract: An electromagnetic field simulation method based on subgridding technique and one-step alternating-direction-implicit-finite-difference time-domain (ADI-FDTD) algorithm is provided herein. The method includes establishing an electromagnetic field simulation model by setting an absorption boundary condition, a periodic boundary condition, a total field boundary condition and a scattering field boundary condition based on the one-step ADI-FDTD algorithm, subgridding technique and FDTD algorithm. The electromagnetic field simulation model is configured to select a detection point and a detection surface, obtain a time-domain waveform diagram of a reflection field of a simulation area, a time-domain waveform diagram of a transmission field of the simulation area and frequency-domain information of the simulation area, and simulate an electromagnetic field, by the electromagnetic field simulation model.