67 results about "Ka band" patented technology

The invention belongs to the technical field of ocean remote sensing detection, and relates to a sea temperature inversion method based on K-Ka band microwave radiometer weak signal enhancement deep learning. Parameters of measured data of the microwave radiometer and reanalysis sea gas parameter data are selected; determining the size of a space-time window based on the brightness temperature characteristics of K and Ka wavebands, and carrying out space-time matching to establish a modeling data set; performing quality control on the modeling data set based on indexes such as quality identification, offshore distance, brightness temperature abnormity and air-sea parameter abnormity; normalizing the modeling data set and splitting the modeling data set into a training set, a verification set and a test set; and constructing a weak signal enhancement DNN model based on the K-Ka band microwave radiometer by using the training set and the verification set, and performing inversion by using the test set to obtain a sea surface temperature product. According to the method, the precision of performing sea surface temperature inversion by using the K and Ka wave band brightness temperatures of the microwave radiometer is improved, the problem of insufficient precision is solved, and a new possibility is provided for inversion of SST on a finer scale.

The invention relates to a farmland parcel identification method based on optical-Ka frequency band SAR feature fusion, and the method comprises the steps: carrying out the feature extraction of an optical remote sensing image through employing an improved ResNet50 network, carrying out the feature extraction of a Ka-SAR image through employing a complex convolution network, triggering a gating mechanism when the cloud coverage rate of the optical remote sensing image exceeds a threshold value, and carrying out the recognition of a farmland parcel. If the cloud coverage rate of the optical remote sensing image does not exceed the threshold value, carrying out feature fusion by adopting a cross-modal attention fusion mechanism; and outputting a farmland plot identification probability graph based on the obtained fusion features based on a UNet + + decoder, and performing optimization and iteration on a result by adopting a geometric constraint loss function to obtain a final identification model. The cross-modal attention fusion method is adopted to perform feature fusion, physical-level collaborative fusion for data features is realized, and meanwhile, the problem that an output result does not meet agricultural management requirements due to the fact that farmland parcels cannot be completely recognized and specific regular geometric attributes of farmland are ignored in a multi-cloud scene is solved.

The invention discloses a low-profile and high-integration broadband dual-circularly-polarized transceiving common-aperture phased-array antenna, which adopts a multi-layer PCB (Printed Circuit Board) laminated structure, comprises a radiation patch layer, a quasi-rectangular patch layer, a metal reflection ground layer and a feed layer from top to bottom, and is combined with a metalized blind hole and a buried hole to form a complete coupling path. A U-shaped groove, a U-shaped metal strip and a C-shaped groove are integrated on a metal reflection ground, and a staggered groove is loaded on a quasi-rectangular patch, so that a K / Ka dual-band separated dual-coupled feed structure is realized, and dual circularly polarized radiation is obtained under the same aperture. The antenna is further provided with outer ring and inner ring plated-through hole arrays, the outer ring plated-through hole arrays are used for constructing an isolation area to improve the isolation degree between wavebands, and the inner ring plated-through hole arrays introduce a horizontal electric field component to improve the circular polarization purity and expand the axial ratio bandwidth. Wide impedance bandwidth and wide axial ratio bandwidth are realized in the K wave band and the Ka wave band, the isolation degree is high, the profile is low, the structure is compact, and the broadband phased array antenna is suitable for broadband phased array systems such as satellite communication terminals and mobile platforms.

The invention belongs to the technical field of antennas, discloses a double-frequency common-caliber high-isolation phased-array antenna in a sparse array distribution mode, and mainly solves the problems that an existing double-frequency common-caliber array antenna sparse distribution optimization algorithm is large in calculation amount and low in design efficiency. According to the invention, through the thirteen-sided Einstein pattern, aperiodic tiling of an infinite plane can be realized through a certain splicing rule. A Ka-band high-frequency antenna and a K-band low-frequency antenna are placed at the gravity center of the Einstein pattern, and the high-frequency antenna and the low-frequency antenna are distributed in a staggered mode in a translation mode. The antenna unit adopts a cross symmetric array antenna, and high isolation of the dual-frequency antenna unit is realized by loading a coaxial filter at the bottom of the antenna unit. The rear end of each antenna unit is connected with a T / R assembly, and array beam scanning is realized by controlling the amplitude and phase of an input signal. The method is low in arrangement cost and high in design efficiency, and can be used for radar, communication, navigation and information confrontation.

The invention discloses a design method of a novel Ka-band microstrip planar array antenna. The antenna has a dual-band working mode. By adopting the one-to-eight power division feed network, efficient feed of the array unit is realized, and good impedance matching is ensured. In addition, the designed decoupling structure DS effectively reduces mutual coupling between the antenna units, the mutual coupling effect is inhibited, and the antenna performance is further optimized. The dual-frequency working frequency band of the antenna is 34-35 GHz and 35-36 GHz, the inter-unit isolation degree is smaller than 35 dB, the average gain exceeds 13 dBi, and the H-surface half-power lobe width is smaller than 20 degrees. The antenna has the advantages of stable bandwidth, low isolation, high gain, high directionality and the like, and is suitable for multiple fields of millimeter wave communication, radar systems, satellite remote sensing and the like.

The invention discloses a low-power-consumption Ku / Ka dual-band transceiver, which relates to a low-power-consumption dual-band transceiving combination in the field of communication, realizes time-sharing work of Ku and Ka bands, and has a radio frequency signal transceiving function. The ultra-low-power-consumption Ku-band band-pass filter is composed of an intermediate frequency unit, a Ku-band receiving and transmitting module, an ultra-low-power-consumption modulation switch circuit, a Ka-band receiving and transmitting module, a Ku-band duplexer, a Ka-band duplexer, a frequency source module and the like. Low power consumption is realized through technologies of circuit multiplexing, pulse modulation switch switching, integrated design and the like. The low-power-consumption miniaturized dual-band transceiver has the advantages of miniaturization, low stray, good amplitude-frequency, stable and reliable performance and the like, can normally work in a relatively severe environment, and is particularly suitable for serving as a low-power-consumption miniaturized dual-band transceiver of a satellite communication terminal.

The invention belongs to the technical field of wireless communication and radar, and discloses a dual-polarization and high-isolation thin Ku / Ka wave band shared aperture phased-array antenna which is composed of a dual-polarization Ku element and four single-polarization Ka elements. According to the low-profile design, the profile height of the antenna is only 2.35 mm, and the antenna is crucial to the application field with limited space. The Ka wave band element works in the frequency band of 32-36 GHz, the Ku wave band element covers 14-18 GHz, and a wide frequency range is provided for various communication and radar applications. High isolation: the dual-polarization port of the Ku wave band shows the isolation higher than 30dB in a scanning range of 0-60 degrees, and the minimum interference between polarization is ensured. In addition, the channel isolation between the Ku wave band and the Ka wave band exceeds 35dB in the Ku wave band and exceeds 18dB in the Ka wave band, so that the signal integrity can be kept and the crosstalk can be reduced.

The invention provides a multi-band composite high-integration TR assembly. The multi-band composite high-integration TR assembly comprises a shell, a front multi-layer board, a back multi-layer board, a C / X / Ku band receiving and transmitting circuit, a C / X / Ku band single receiving circuit and a Ka band receiving and transmitting circuit, wherein the front multi-layer board and the back multi-layer board are connected in the shell, the C / X / Ku band receiving and transmitting circuit is connected with the front multi-layer board, and the Ka band receiving and transmitting circuit is connected with the back multi-layer board. The low-cost scheme design of an all-solid-state microwave multilayer board suitable for batch production and testing is adopted, ports and transmission line layout are reasonably designed, multi-band composite mode transmission is achieved in the form of the front face and the back face, a C / X / Ku-band transmitting circuit and an H-polarization receiving circuit are integrated on the front face, and the transmission efficiency is improved. A C / X / Ku frequency band V polarization receiving circuit and a Ka frequency band receiving and transmitting circuit are integrated on the reverse side, different functional circuits are respectively transmitted through a microstrip line and a strip line through an interface circuit structure covering 1-40 GHz and an in-board vertical transition structure, the isolation degree of different circuits is improved, mutual crosstalk between different signals is avoided, and the transmission efficiency is improved. And the functions of high integration, high consistency, ultra wide band, numerical control phase shift, numerical control attenuation and the like of the assembly are realized.

The invention belongs to the technical field of antennas, and discloses an S / Ka waveband common-aperture antenna and communication equipment, and the antenna comprises a first dielectric plate and a second dielectric plate which are stacked from top to bottom. The top surface, the middle and the bottom surface of the first dielectric plate are respectively provided with a rectangular patch array, a first metal through hole and a first metal layer; wherein the rectangular patch array, the first metal through hole and the first metal layer form a magnetoelectric dipole antenna array; the magnetoelectric dipole antenna array works in a Ka wave band and is used for realizing satellite communication; the top surface, the middle and the bottom surface of the second dielectric plate are respectively provided with a second metal layer, a second metal through hole and a third metal layer; wherein the second metal layer, the second metal through hole and the third metal layer form a low-profile monopole antenna; the low-profile monopole antenna works in an S wave band and is used for realizing ground equipment communication; the structure is simple, different wave beams and polarization characteristics can be realized, the space utilization rate of the antenna is effectively improved, and the integration degree is high.

The invention provides a broadband circularly polarized antenna array of a millimeter wave Ka band, and belongs to the field of antennae, the broadband circularly polarized antenna array comprises a first dielectric substrate, a second dielectric substrate, a third dielectric substrate and a fourth dielectric substrate which are stacked from bottom to top, an SIW cavity structure is arranged in the first dielectric substrate, a first gap is formed in a metal ground on the upper surface of the first dielectric substrate, and a second gap is formed in a metal ground on the upper surface of the fourth dielectric substrate. A cross-shaped SIW feed structure is arranged in the second dielectric substrate, a second gap located above the first gap is formed in the metal ground on the lower surface of the second dielectric substrate, a third gap is formed in the metal ground on the upper surface of the second dielectric substrate, a plurality of antenna units are arranged on the upper surface of the fourth dielectric substrate, each antenna unit comprises two semicircular patches, and the two semicircular patches are arranged in parallel. A suspension column is arranged in a gap between the two semicircular patches, a parasitic dipole is arranged outwards from the outer side of the suspension column, and the parasitic dipole comprises a rectangular patch and a spiral arm patch clockwise connected to one end of the rectangular patch; the radiation efficiency of the antenna in the millimeter wave band is improved, and the axial ratio bandwidth completely covers the Ka band.

The application belongs to the technical field of antennas, and discloses an S / Ka-band common-aperture antenna and communication equipment, which comprises a first dielectric plate and a second dielectric plate stacked from top to bottom; the top surface, the middle and the bottom surface of the first dielectric plate are respectively provided with a rectangular patch array, a first metal through hole and a first metal layer; wherein the rectangular patch array, the first metal through hole and the first metal layer form a magneto-electric dipole antenna array; the magneto-electric dipole antenna array works in the Ka-band and is used for realizing satellite communication; the top surface, the middle and the bottom surface of the second dielectric plate are respectively provided with a second metal layer, a second metal through hole and a third metal layer; wherein the second metal layer, the second metal through hole and the third metal layer form a low-profile monopole antenna; the low-profile monopole antenna works in the S-band and is used for realizing ground equipment communication; the application has a simple structure, can realize different beams and polarization characteristics, effectively improves the space utilization rate of the antenna and has high integration.

The application provides an airborne dual-band weather radar detection method, which comprises the following steps: S1: adopting a dual-band common-aperture antenna to time-divisionally emit X-band electromagnetic waves and Ka-band electromagnetic waves; S2: a weather radar receives the X-band electromagnetic waves and the Ka-band electromagnetic waves and performs ground clutter suppression; S3: calculating reflectivity Rrf x according to the X-band electromagnetic waves; S4: calculating reflectivity Rrf ka , velocity V ka and spectral width W ka ; S5: performing analysis on weather targets and displaying analysis results. The detection method realizes cloud detection by using the Ka band on the basis of meeting original X-band weather rainfall detection functions, realizes dangerous weather identification and dangerous area warning by comprehensively considering the spatial structure of the cloud and Doppler information, marks weather seriously threatening flight safety in a display picture, and reminds pilots to pay attention. The detection method comprehensively improves the detection perception and display capability of the airborne weather radar on various weathers, further improves flight safety, and reduces unnecessary deviation.

This invention discloses a broadband circularly polarized integrated feed transmission array antenna covering the entire Ka-band, comprising an array surface and an integrated feed. The phase center of the integrated feed coincides with the focal point of the array surface, illuminating the array surface perpendicularly and forming a 45-degree angle with the array surface in the horizontal direction. The array surface comprises multiple array elements of different sizes arranged linearly. Each array element includes two orthogonally arranged first and second dielectric substrates, which have the same height but different thicknesses. The integrated feed comprises a stacked first and second PCB board. A substrate integrated waveguide is disposed on the first PCB board with coupling slots, and a substrate integrated waveguide cavity and annular metal patches surrounding the substrate integrated waveguide cavity are disposed on the second PCB board. This invention achieves a wide axial ratio bandwidth and gain bandwidth, and has the advantages of low profile, light weight, easy fabrication, and low cost.

This invention discloses a user-end beam control system for a KuKa dual-band multi-beam antenna, comprising: an FPGA module for receiving instruction information from a payload integrated electronics system, generating various control signals and sending them to the KuKa dual-band multi-beam antenna, and also for receiving telemetry information from the KuKa dual-band multi-beam antenna, integrating it into a telemetry data packet and sending it to the payload integrated electronics system; a clock management module for receiving a reference clock signal from an external frequency source and generating the operating clock required by the FPGA module; an interface module for providing a serial communication interface and serial driver, an LVDS control interface and driver, and a debugging interface; and a debugging module for debugging the software running within the FPGA chip. This invention can quickly and independently adjust the beam pointing of the Ku and Ka bands of the KuKa dual-band multi-beam antenna and acquire telemetry data from the KuKa dual-band multi-beam antenna in real time.

The invention provides a Ka-band highly integrated phased array packaged antenna for low-orbit satellite communications, belonging to the field of antennas. The antenna comprises N 2×2 sequentially rotating subarrays, each of which comprises four antenna units, each of which comprises a parasitic patch, a driving patch, an upper metal grounding layer, a lower metal grounding layer, and a dielectric substrate. The driving patch is located on the lower surface of the lower dielectric substrate, the parasitic patch is located on the upper surface of the lower dielectric substrate, the lower surface of the lower metal grounding layer has two feeding ports, each feeding port is respectively connected to an L-shaped feeding probe through a feeding metallized via hole to generate horizontal or / and vertical excitation to the driving patch, metallized blind holes arranged around the feeding metallized via hole array form an inner metal shielding cavity, and metallized blind holes arranged along the boundary array of the lower dielectric substrate form an outer metal shielding cavity; the antenna has a wide working bandwidth, excellent radiation performance, and rich polarization functions.

The application discloses a kind of low-orbit satellite ultra-wideband navigation signal acquisition method and system, to solve the existing low-orbit satellite ultra-wideband navigation signal acquisition method, signal can not be locked, finally lead to the technical problem of low acquisition success rate.It is to obtain the low-orbit satellite pseudo-random noise code corresponding to ka band low-orbit satellite signal and multiple low-orbit satellite ultra-wideband navigation signals;According to preset sampling rate, preset skip time, ka band low-orbit satellite signal, generate complex signal and original intermediate frequency signal;Based on each low-orbit satellite pseudo-random noise code, pseudo-code spectrum library construction is carried out, and the pseudo-code spectrum library is output;Based on the known intermediate frequency parameter of original intermediate frequency signal, determine the discrete frequency search sequence, and combine the complex signal, pseudo-code spectrum library to construct matrix, and output three-dimensional result matrix;Using three-dimensional result matrix, each low-orbit satellite ultra-wideband navigation signal is acquired and determined, and multiple acquisition successful low-orbit satellite ultra-wideband navigation signals are determined.

The application discloses a Ka-band eight-way power combiner, which comprises a shielding box body, wherein a straight-through input port, an input waveguide cavity, an input coplanar magic T, a secondary waveguide power division module, a waveguide-microstrip double-probe conversion structure, a secondary waveguide power synthesis module, an output waveguide cavity, an output coplanar magic T and a straight-through output port are sequentially arranged in the shielding box body along a signal transmission direction; the secondary waveguide power division module and the secondary waveguide power synthesis module both adopt an E-T junction structure and are integrated with a three-stage waveguide E-plane stepped structure, so as to realize impedance matching from an input end to an output end; the Ka-band eight-way power combiner has high synthesis efficiency, extremely low amplitude imbalance and phase imbalance in the Ka band through multi-stage waveguide impedance matching, optimized double-probe conversion and symmetrical layout design. The combiner has the advantages of compact structure, large power capacity, simple machining and assembly and good stability.

The invention relates to the technical field of microwave ferrite devices, and discloses a K-to-Ka waveband miniaturized broadband microstrip isolator, which comprises a permanent magnet, a ceramic chip, a soldering lug, a circuit layer, a resistive film and a single ferrite which are sequentially laminated from top to bottom, a single ferrite substrate is made of a gyromagnetic material, and the isolator realizes a gyromagnetic function through the single ferrite substrate. The K-to-Ka wave band miniaturized broadband microstrip isolator assists the single ferrite substrate in stably playing a gyromagnetic function, the soldering lug, the ceramic chip and the permanent magnet are stacked to assist in improving the overall performance of the isolator, and the ceramic chip can play a role in insulation and protection to avoid electrical interference between the permanent magnet and the soldering lug, so that the service life of the isolator is prolonged. The use reliability and safety of the isolator are improved, the installation space occupation in radar communication and satellite communication equipment can be reduced through the miniaturization design of the overall structure, the overall size and weight of auxiliary equipment are reduced, and the portability and space compatibility of the equipment are improved.

The invention belongs to the technical field of microwaves, and particularly relates to a slot line-half-mode SIW composite transmission line for microwave / millimeter wave transmission, which is characterized in that a half-mode SIW structure is arranged in a sandwich structure, and a first metal layer synchronously loads a conical microstrip feeder line and a horn-shaped microstrip feeder line structure; the second metal layer is used as a metal structure with a floor function, and the design mode of additionally loading a slot line and an interdigital capacitor enables the device to realize transmission of an S wave band and a Ka wave band at the same time. Wherein in the S wave band, the horn-shaped micro-strip structure of the first metal layer is used for carrying out coupled feeding on the slot line, and in the Ka wave band, the conical micro-strip structure of the first metal layer is used for directly feeding the half-mode SIW; meanwhile, the second metal layer loads an interdigital capacitor at the tail end of the half-mode SIW to complete filtering, and finally the composite transmission line feed structure supporting synchronous transmission of the half-mode SIW and the slot line is constructed. The machining process is simplified, and the machining cost is reduced.

The application discloses an interferometric SAR synchronization method of radar inter-satellite link combined with Ka-band link cross correction, and aims at the problems of interrupting normal SAR imaging or existing initial phase winding in the existing synchronization link method, and proposes a cross correction scheme of X-band radar inter-satellite link combined with Ka-band high-precision synchronization link. The system adopts a common reference source to ensure the phase correlation, and different synchronization time sequences are designed, that is, the X-band link is synchronized at a low frequency to eliminate the initial phase winding, and the Ka-band link is synchronized at a high frequency same as the SAR pulse repetition frequency (PRF) to realize high-precision phase measurement. During ground processing, the initial phase error of the Ka-band compensation function is corrected by using the X-band synchronization data, so that a high-precision phase synchronization compensation function is obtained, and the echo of the secondary satellite is compensated. The application solves the problem of initial phase winding under the premise of not interrupting the normal SAR imaging time sequence, and significantly improves the phase synchronization precision, image quality and absolute height measurement reliability of the dual-satellite interferometric SAR system.

The present application relates to a farmland plot recognition method based on optical-Ka band SAR feature fusion, which uses an improved ResNet50 network to extract features from optical remote sensing images, uses a complex convolution network to extract features from Ka-SAR images, triggers a gating mechanism when the cloud coverage of the optical remote sensing image exceeds a threshold, and uses a cross-modal attention fusion mechanism for feature fusion if the cloud coverage of the optical remote sensing image does not exceed the threshold; the obtained fusion features are output as farmland plot recognition probability maps based on a UNet++ decoder, and a geometric constraint loss function is used to optimize and iterate the results to obtain the final recognition model. The present application uses a cross-modal attention fusion method for feature fusion, realizes physical-level collaborative fusion of data features, and solves the problems of incomplete recognition of farmland plots in cloudy scenes and ignoring the specific regular geometric properties of farmland, which leads to output results that do not meet the needs of agricultural management.

The invention belongs to the technical field of millimeter wave phased-array antennas, and particularly discloses a circularly polarized spherical phased-array antenna for Ka-band operation, which comprises a hemispherical antenna base and a plurality of radiation units, the plurality of radiation units are arranged on the hemispherical surface of the hemispherical antenna base in an array form; the circularly polarized spherical phased-array antenna is configured in a frequency range from 27GHz to 29GHz, so that + / -90-degree beam scanning of any azimuth tangent plane is realized. The scanning angle limitation of a planar array is broken through, and + / -90-degree continuous scanning of any tangent plane is realized; meanwhile, the array element spacing and the arrangement density are optimized in combination with the short wavelength characteristic of the Ka wave band, the mutual coupling effect of the high frequency band is reduced, and the problem that the actual use effect is poor due to the fact that the large-angle scanning radiation capacity of an existing Ka wave band planar phased array antenna is limited and the polarization purity is reduced is solved.

The invention relates to a Ka frequency band broadband multi-beam communication system based on a 5GNTN system, which can work under the 5GNTN system through the cooperative work of a 4T4R radio frequency transceiver chip, a signal processing FPGA, a monitoring FPGA, a clock PLL, an optical module and a power supply module, and the Ka frequency band broadband multi-beam communication system can work under the 5GNTN system through the cooperation of the 4T4R radio frequency transceiver chip, the signal processing FPGA and the optical module. And the maximum support bandwidth of the system is greatly improved while the number of supported beams is greatly improved, so that the uplink and downlink rates reach the level of 5Gbps.

The present invention discloses a K / Ka band dual-frequency conical beam antenna, comprising a high-frequency filtering and feeding module, a low-frequency power splitting and feeding module, and a nested horn module; the nested horn module comprises a circular waveguide horn and a coaxial horn nested outside the circular waveguide horn; the high-frequency filtering and feeding module is used to filter and perform mode conversion on input high-frequency electromagnetic energy, and output electromagnetic waves in a coaxial TEM mode; the electromagnetic waves in the coaxial TEM mode are used to excite the circular waveguide horn; the low-frequency power splitting and feeding module is used to perform power distribution on the input low-frequency electromagnetic energy, and output a plurality of electromagnetic waves with equal amplitude and phase; the plurality of electromagnetic waves with equal amplitude and phase are used to symmetrically excite the coaxial horn; the present invention can realize the radiation characteristics of a dual-band dual-conical beam, effectively improving the detection range of the antenna; the filtering function is integrated in the high-frequency filtering and feeding module, effectively improving the anti-interference capability of the antenna; and at the same time, it has high power capacity and radiation efficiency.

A Ka band monopulse antenna system with a compact size (diameter: 160 mm; height: 25 mm). The monopulse antenna system consists of a monopulse comparator; an unequal power divider and an array of 448 radiating slot antenna elements. The research results of the invention are as follows: the antenna operates in the Ka band frequency range; the realized gain at the center frequency is 34.2 dBi; the sidelobe level of the sum beam on the two E and H planes is less than −25 dB; the difference between the two peaks of the beams on the difference beam is small (about 0.1 dB); the peak-null difference of the difference beam is greater than 43 dB.

The invention discloses a preparation method and application of a polyimide / aminated graphene oxide (PI / AGO) composite wave-absorbing film. The method comprises the following steps: preparing aminated graphene oxide (AGO) by grafting p-phenylenediamine to graphene oxide; the preparation method comprises the following steps: dispersing AGO in N, N-dimethylacetamide in an inert atmosphere, and carrying out low-temperature polycondensation on the N, N-dimethylacetamide, 4, 4 '-diaminodiphenyl ether and 3, 3', 4, 4 '-benzophenone tetracarboxylic dianhydride to prepare a polyamide acid / AGO solution; the composite film is obtained through film casting and stepped thermal imidization (150-300 DEG C gradient heating). The innovation lies in that AGO amino groups are bonded with polyimide monomers, nanoscale dispersion (the content is 1.6-2.8 wt%) is achieved, and the problems of high-temperature oxidation and interface defects of traditional filler are solved. The obtained film shows remarkable wave absorbing performance in a Ka wave band (26.5-40GHz), and is suitable for the fields of electromagnetic protection of high-frequency electronic equipment and radar stealth.

Provided is a 10W power amplifier for Ka band. The power amplifier includes, a drive amplifier; an intermediate stage amplifier composed of two transistors; a final stage amplifier composed of 4 transistors; a GCPW, waveguide, and a first spatial combiner unit which are sequentially connected between the drive amplifier and the intermediate stage amplifier to divide a signal output from the drive amplifier and provide the divided signal to the intermediate stage amplifier; a second spatial combiner unit, a waveguide divider, and a third spatial combiner unit which are sequentially connected between the intermediate stage amplifier and the final stage amplifier to divide signals output from the intermediate stage amplifier and provide the divided signals to the final stage amplifier; and a fourth spatial combiner unit and a waveguide combiner which are sequentially connected to the output terminal of the final stage amplifier to combine signals output from the final stage amplifier and finally output the combined signals.

The invention relates to a preparation method and application of a polyimide / sulfur-doped aminated graphene (PI / S-AGO) composite wave-absorbing film. The preparation method is realized by three steps of: firstly, bonding graphene oxide with p-phenylenediamine to prepare aminated graphene (AGO); then enabling AGO to react with sodium polysulfide at 95 DEG C, and embedding sulfur atoms into graphene crystal lattices in a C-S bond form to form sulfur-doped graphene (S-AGO); finally, the S-AGO, 4, 4 '-diaminodiphenyl ether and 3, 3', 4, 4 '-benzophenone tetracarboxylic dianhydride are subjected to low-temperature polycondensation and gradient imidization (150-300 DEG C), and the composite film is prepared. The innovation lies in that lattice defects and polar functional groups introduced by sulfur doping significantly enhance the interface / dipole polarization effect, so that the reflection loss of the material at the Ka waveband (26.5-40 GHz) and 34.8 GHz reaches-65.8 dB, the effective absorption bandwidth is 6.42 GHz (the corresponding thickness is 3.15 mm), the performance is improved by 61% compared with that of an undoped system, and the material is suitable for the fields of 5G communication (28 / 39 GHz), radar stealth and high-frequency electromagnetic shielding.

The present invention discloses a method for quickly testing the directional pattern of a phased array antenna based on the segment function of a vector network. The system can quickly measure the directional pattern indicators of phased array antennas in the L, S, C, X, Ku, K, and Ka bands, thereby providing relevant evidence for the research and debugging of phased array antennas. The present invention includes modules such as a test turntable, a phased array antenna test fixture, a vector network analyzer, a feed turntable, a standard gain antenna, a radio frequency matrix switch, a timing controller, a computer, and a programmable power supply. During the process of the turntable moving at a constant speed from the starting position to the stop position, the turntable continuously reports the current position; after detecting that the trigger position has been reached, the timing controller automatically controls the phased array antenna to generate a beam and triggers the segment of the vector network to scan and finally complete the directional pattern test.

The invention provides a full-band three-dimensional wave-absorbing metamaterial, which comprises a plurality of basic structure units arranged in a periodic array, and is characterized in that each basic structure unit comprises a first electromagnetic loss three-dimensional superstructure to a sixth electromagnetic loss three-dimensional superstructure and a metal backboard which are sequentially arranged from top to bottom; the first electromagnetic loss three-dimensional superstructure to the sixth electromagnetic loss three-dimensional superstructure are loaded with resistive frequency selective surfaces. The invention has the following beneficial effects: the resistive frequency surface, the pure metal patch and the electromagnetic loss three-dimensional superstructure are combined to carry out multi-dimensional coupling absorption design, so that the full-band absorption performance is realized in the current L, S, C, X, Ku, K and Ka bands with relatively high utilization rate, and certain electromagnetic loss performance is still shown in the V and W bands; the thickness is small, and the maximum oblique incidence angle is not smaller than 70 degrees, so that the requirements of thin-layer and low-surface-density electromagnetic wave-absorbing materials working in the current full-frequency-band range are met.