75 results about "Ku band" patented technology

The invention relates to the technical field of radar signal processing, in particular to a radar target analytical calculation method based on multi-dimensional data fusion and a radar device. Comprising the following steps: deploying a multi-band radar sensor array comprising an X band, a C band and a Ku band in a radar monitoring area; performing pulse compression and Doppler processing on the time domain echo signal, and extracting a time domain feature; spectral analysis is carried out on the frequency domain signals, and frequency domain features are extracted; performing angle estimation on the spatial signals, and extracting spatial features; a dynamic weight distribution model is constructed, a fusion weight is calculated through an adaptive algorithm based on three-dimensional quality indexes of a real-time signal-to-noise ratio (SNR), feature stability (SI) and data integrity (CI), and a joint representation vector containing time domain, frequency domain and space multi-dimensional information is generated. According to the invention, by deploying the multi-band radar sensor array, the recognition capability of the subtle feature difference of the target is improved.

The invention relates to the technical field of trajectory tracking, in particular to an unmanned aerial vehicle trajectory tracking target classification method and system based on a multi-frequency-band radar, and the method comprises the following steps: synchronously collecting original radar echo data of a millimeter wave frequency band, a Ku frequency band and an L frequency band, and generating a multi-frequency-band data set comprising a timestamp, an azimuth angle and a pulse sequence; extracting multi-dimensional features of the target from the synchronized multi-band data set, and generating a multi-band feature vector; constructing a dynamic trajectory association matrix, and determining the space-time continuity of a target trajectory through a trajectory association algorithm based on an attention mechanism; constructing a lightweight classification model; performing online classification on the real-time multi-band feature vectors by using a lightweight classification model, and outputting a target type and confidence; according to the method, capture of the motion state of the target is enhanced, rapid response can be made to tiny motion and change of the target in a complex scene, and therefore more comprehensive and accurate time sequence context information is provided for subsequent classification tasks.

The invention discloses a multiband high-voltage power supply control system and a normalization control and protection method thereof, and relates to the technical field of power supply control, and the method comprises the steps: collecting multi-mode signals of S, C and Ku band high-voltage power supply systems and a cooling system; an SDAE deep network and an integrated learning AdaBoost framework are combined to construct a fault diagnosis model, and a fault type and confidence are obtained according to signal features; when a fault occurs, high-voltage output of a corresponding power supply unit is cut off and reported through an isolation interface, and a deep reinforcement learning agent is used for carrying out protection action intelligent decision making; a digital twinborn model of a power supply unit is constructed, an improved grey wolf optimizer is used for multi-task collaborative optimization, optimized system parameters are acquired and issued to a PLC for execution, and waveband output stability is ensured. According to the invention, high reliability, rapid response and intelligent operation and maintenance of the multi-band high-voltage power supply system are realized through deep integration of multi-source signal acquisition, intelligent fault diagnosis, adaptive protection decision and digital twinning optimization.

The invention relates to a multiband radio frequency signal transmitting and receiving method, belongs to the technical field of microwave integrated circuits, and solves the problem that multiband integrated broadband transmitting and receiving are difficult to realize in an existing radio frequency transmitting and receiving mode. The method is divided into a multiband radio frequency signal receiving / transmitting method. The receiving method comprises the following steps of: performing up-conversion on a received radio frequency input signal to a K wave band through first-stage frequency mixing, performing down-conversion on the received radio frequency input signal to an S / C wave band through second-stage frequency mixing, performing down-conversion on the received radio frequency input signal to an L wave band intermediate frequency through third-stage frequency mixing, and generating a first L wave band intermediate frequency output signal; the transmitting method comprises the steps that an obtained second L-band intermediate-frequency output signal is subjected to fourth-stage frequency mixing up-conversion to the S / C band, is subjected to fifth-stage frequency mixing up-conversion to the K band and is subjected to sixth-stage frequency mixing down-conversion to the S / C / X / Ku band, and a radio-frequency output signal is generated; the first-stage frequency mixing up-conversion and the sixth-stage frequency mixing down-conversion are realized by the same bidirectional microwave link working in up-conversion and down-conversion regulation and control states respectively.

The invention discloses a ground-based radar calibration deviation estimation method based on satellite-ground precipitation radar verification, and the method mainly comprises the steps: carrying out the frequency correction of a satellite-borne radar SR reflectivity factor from a Ku wave band to an S wave band, and carrying out the projection conversion of a polar coordinate system with a ground-based radar GR as a center after the correction; the converted SR and GR reflectivity factors are subjected to overlapping matching in time and space which are accurate to seconds; the mean value precision is improved through inverse distance weight, and the precipitation space heterogeneity of SR and GR in the matching space is reduced through the in-pixel non-uniform beam filling quality control technology; a satellite-ground precipitation radar quality control factor threshold standard system is established, whole-process quality control is carried out in the calibration deviation estimation process, and finally ground-based radar GR calibration deviation estimation is realized through comparison verification of spaceborne radar SR and ground-based radar GR reflectivity factors after quality control processing. According to the invention, the error of satellite-ground radar inspection can be effectively reduced, and the precision of rainfall estimation is improved.

For improved Ku band communications, an antenna system includes a planar antenna surface, at least one waveguide feed network, and a waveguide. The planar antenna surface is coupled to at least one port. The at least one waveguide feed network includes an H plane junction splitter and at least two E plane junction splitters. The H plane junction splitter is disposed on a channel septum in a channel. A splitter axis of the channel septum and the H plane junction splitter is rotated about a P axis. The at least two E plane junction splitters are each disposed on septum and coupled to the H plane junction splitter via the channel. The waveguide is coupled to the waveguide feed network.

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, which belongs to the technical field of the plasma amplitude limiter, discloses a high-power ultra-wideband plasma amplitude limiter comprising an input window, a discharge gap, an output window and an amplitude limiting module. The plasma amplitude limiter is reliable in structure, ultra-wide in band and high in power capacity, is located at the front end of a receiver, and plays a role in protecting high-power microwave attacks. The plasma amplitude limiter disclosed by the invention can bear high-power microwave attack with the highest power magnitude of 10kW in the widest frequency band range of 10GHz, and a receiving access can be quickly switched off within 10ns, so that the aim of protecting the whole communication system is fulfilled; a coaxial ultra-wideband design technology is adopted, a full-hard welding structure is adopted, the structure is stable and reliable, and the frequency band range of the plasma amplitude limiter tube covers L, S, C, X and Ku wave bands; the multi-stage pointed-cone-shaped discharge gaps are adopted, leakage power is reduced stage by stage, and therefore safe work of the amplitude limiting chip is guaranteed, and finally the plasma amplitude limiter with high bearing power and short response time is achieved.

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 discloses an X / Ku frequency band high-isolation heterogeneous common-caliber array antenna applied to satellite communication, and belongs to the technical field of common-caliber antennas. The heterogeneous common-caliber antenna comprises a parasitic patch layer, a first heterogeneous dielectric layer, a radiation patch layer, a second heterogeneous dielectric layer, a first grounding plane, a first dielectric layer, a feed network layer, a second dielectric layer, a second grounding plane and a coaxial line which are tightly attached in sequence from top to bottom. According to the heterogeneous common-caliber antenna, the X-waveband antenna and the Ku-waveband antenna share the same caliber face, the X-waveband antenna and the Ku-waveband antenna are heterogeneous in a medium nesting mode, the isolation degree of the two kinds of antennas in the same caliber face is very high, receiving and sending work can be conducted at the same time, and the miniaturization effect is outstanding; the array formation based on the heterogeneous common-caliber antenna can realize the simultaneous work of the X / Ku frequency band antennas under the half-wavelength spacing of the Ku frequency band, and the radiation performance is hardly influenced.

The present invention discloses a broadband dual-polarization antenna array, comprising a radiating network and a feeding network. The feeding network is used to convert electromagnetic waves in the form of a TEM mode input thereto into electromagnetic waves in the form of a TE10 mode and transmit them to the radiating network. The radiating network is used to radiate the electromagnetic waves transmitted thereto by the feeding network into free space. The radiating network is realized by arranging a partition structure consisting of four levels of metal steps in a rectangular slot in combination with metal branches arranged above the partition structure. The feeding network is realized based on a full parallel feed network consisting of a ridge waveguide structure, a micro-coaxial structure and a magic T. The advantage is that while having high gain and high efficiency, the bandwidth can cover the Ku band, meeting the requirements of Ku-band satellite communications.

The application provides an emergency information service system and method based on satellite communication and ground mobile communication fusion, the system comprises: a high flux satellite fixed station terminal, a Ku band 0.6 meter VSAT terminal is adopted, an ACU and a MODEM are integrated, a three-axis structure and a carbon fiber antenna are provided; a ground mobile communication subsystem, comprising a 4G skin base station, a security gateway and a signaling gateway; a multi-WAN port routing device realizes dynamic load balancing of satellite and ground broadband; an emergency power supply system is composed of a generator and a power bank to form a three-level power supply; a network management and monitoring system supports remote configuration and AI optimization. The method comprises the steps of disaster monitoring, system activation, network establishment, signal coverage, communication service and management and maintenance. The application combines AI driven network optimization to quickly establish a reliable communication network in an emergency scene through satellite and ground communication fusion, has the characteristics of wind load resistance, low time delay, intelligent scheduling and the like, and significantly improves the emergency communication guarantee capability.

The invention discloses a non-uniform phased-array antenna arrangement method and system of a ku frequency band, and relates to the technical field of array antenna design, and the method comprises the steps: building a target function with a sidelobe level, a beam width and a scanning range as a joint optimization target; in the ku frequency band, a non-uniform spacing distribution scheme of the array antennas is searched based on the adaptive crossover and mutation probability, and the distribution scheme is determined according to an objective function evaluation result; and performing error compensation optimization on the initial distribution by combining the online monitoring data and the target parameter difference, and generating a final antenna arrangement scheme. The problems that in the prior art, the arrangement optimization target is single, and the performance and cost of the phased-array antenna are affected are solved, and the technical effects of online monitoring, complete monitoring and good early warning capacity are achieved.

The present invention discloses a multi-channel gyromagnetic filter magnetic circuit, belonging to the technical field of magnetic device integration, which includes a lower magnetic circuit (1), an upper magnetic circuit (2), the magnetic pole columns (3) of the upper and lower magnetic circuits, a main coil (4), a compensation coil (5), a coil installation groove (6), and a multi-channel resonant circuit (7); wherein, the coil installation groove (6) is located on the end face of the upper and lower magnetic pole columns (3) and is perpendicular to the end face, dividing the end face of the magnetic pole column (3) into the number n of integrated filter channels. The compensation coil (5) is sleeved in the coil installation groove (6), and the number thereof is not less than n-1; the magnetic circuit of the present invention can achieve a frequency compensation ability of 0-200 MHz in the P-Ku band, the number of filter resonant circuit stages is not limited, and it has a wide applicability, and can cover the multi-channel integration of all gyromagnetic filters; it is beneficial to reduce the power consumption of the device; it is beneficial to control the compensation frequency modulation range and improve the reliability; and it is beneficial to control the manufacturing cost of the filter product and improve the production efficiency.

The invention provides a ku-frequency-band unmanned aerial vehicle countering radar and a target detection method and device, and belongs to the technical field of radars, and the ku-frequency-band unmanned aerial vehicle countering radar comprises a transmitting system which is used for outputting electromagnetic waves of a ku frequency band; the antenna is used for performing directional radiation on the electromagnetic waves of the ku frequency band and receiving echo signals reflected by a target object; the antenna comprises at least one array plane module, and the array plane module is detachably arranged. The receiving system is used for sending the echo signal received by the antenna to the signal processing system; the timing synchronization system is used for providing synchronous clock signals for the transmitting system and the receiving system; and the signal processing system is used for detecting the unmanned aerial vehicle based on the echo signals, determining motion state parameters of the unmanned aerial vehicle and outputting the motion state parameters of the unmanned aerial vehicle to the countering execution system. According to the ku-band unmanned aerial vehicle countering radar and the target detection method and device provided by the invention, the universality and flexibility of the unmanned aerial vehicle countering radar can be improved.

The invention discloses a cubic ZIF-67 / MXene wave-absorbing material as well as a preparation method and application of the cubic ZIF-67 / MXene wave-absorbing material. The preparation method comprises the following steps: reacting lithium fluoride, concentrated hydrochloric acid and deionized water to generate hydrofluoric acid, and etching an MAX phase to obtain MXene; the preparation method comprises the following steps: dispersing CoCl2. 6H2O, cetyl trimethyl ammonium bromide (CTAB) and MXene in deionized water to form a solution A; dispersing 2-methylimidazole in deionized water to form a solution B; quickly pouring the solution A into the solution B, stirring and reacting, centrifuging, freeze-drying and annealing to obtain the cubic ZIF-67 / MXene wave-absorbing material. The material is of a multi-layer sandwich structure, the reflection loss at 16.69 GHz can reach-20.79 dB, the matching thickness is 1.87 mm, the effective absorption bandwidth (RL is smaller than or equal to-10 dB) is 6.19 GHz (11.81-18.00 GHz), and the Ku wave band is covered. The method is environment-friendly in process, low in cost, simple and convenient to operate and suitable for large-scale production, and has application prospects in the fields of microwave absorption, infrared stealth and photocatalysis.

This invention discloses a wide-bandwidth, wide-angle metamaterial microwave absorber covering the L, S, C, X, and Ku bands, belonging to the field of stealth technology. The unit structure of the microwave absorber includes an upper FR4 plate with three-dimensional printed high-resistivity carbon paste, a middle paper honeycomb support layer, and a bottom magnetic material attached to a metal plate. The upper FR4 plate provides microwave absorption performance at mid and high frequencies, while the bottom magnetic material provides microwave absorption performance at low frequencies. The two are fixed by the paper honeycomb of the middle support layer. By combining a three-dimensional microwave absorber with magnetic materials, this invention achieves wide-bandwidth, wide-angle microwave absorption performance. The composite microwave absorber structure constructed by this invention has high structural strength and achieves lightweight design.

The application discloses a cross-band frequency reconfigurable planar phased array antenna with a modular chip antenna unit, which is composed of a 2N*2N chip antenna unit array arrangement, N is a natural number greater than or equal to 1, and the chip antenna unit sequentially comprises a dielectric matching layer module, an air layer, a chip antenna module and a multilayer PCB carrier board module from top to bottom; the dielectric matching layer module and the chip antenna module interact with the electromagnetic waves radiated thereby, so as to improve the active standing wave ratio and cross polarization characteristics of the chip antenna unit, and the air layer is used for adjusting the distance between the dielectric matching layer module and the chip antenna module; the dielectric matching layer module, the air layer, the chip antenna module and the multilayer PCB carrier board module jointly realize the cross-band frequency reconfiguration function of the chip antenna unit from the C band to the Ku band. The frequency reconfiguration range of the application is 10 GHz, and the problems of single working frequency band, poor anti-interference ability and low aperture utilization of the traditional phased array antenna are solved.

The application belongs to the technical field of controllable metamaterials and radomes, and particularly relates to a controllable low-profile dual-polarized A-T-A absorbing and transmissive metasurface and radome, which comprises an absorbing screen and a transmissive screen arranged in layers; the absorbing screen comprises a plurality of periodically arrayed absorbing screen units, each of which comprises a dielectric substrate I, a metal foil micro-unit attached to the upper surface of the dielectric substrate I, and an energy consumption piece loaded on the metal foil micro-unit; the application improves the RCS reduction effect of metal, enables the antenna to maintain good radiation characteristics in the Ku band, and enables free communication; meanwhile, the application has good absorbing performance in the X band and the Ku band on both sides of the passband, reduces the RCS of the antenna, and achieves the stealth purpose of the antenna.

The application belongs to the technical field of satellite communication interference protection, and specifically discloses an interference cancellation device and method for a Ka and Ku frequency band multi-mode satellite communication ground station, wherein the device comprises: a sampling antenna module, which is used for collecting Ku / Ka frequency band sampling signals from space; a radio frequency receiving module, which is used for selecting the polarization direction of the sampling signals based on the polarization mode of the satellite communication antenna and converting the sampling signals into sampling intermediate frequency signals; a sampling signal selection module, which is used for dividing the sampling intermediate frequency signals into sub-signals and selecting different frequency band sub-signals based on the working frequency band of the satellite communication terminal; and a signal processing module, which is used for obtaining interference cancellation output signals free of interference by performing interference cancellation on the fth satellite communication signal through an adaptive filtering algorithm based on N-path target frequency band sampling intermediate frequency sub-signals. The application is suitable for the satellite communication ground station for realizing Ka / Ku dual-band multi-mode communication through a radio frequency switch matrix shared satellite communication antenna, and realizes mutual decoupling of anti-interference processing between different satellite communication terminals.

This invention discloses a method for beam control of unconventional radar arrays. The method includes establishing a reference benchmark and initializing array parameters based on the unconventional radar array, determining core radar control parameters, determining radar beam control parameters, determining complex weighting coefficients for radar digital receiver multi-beam synthesis, and completing the radar array digital receiver multi-beam synthesis. This solution is applicable to unconventional phased array antennas with subarray-level random rotation and subarray-level random misalignment, and is compatible with beam control of conventional arrays. It has low computational complexity and introduces beam pointing accuracy error ≤0.01° and phase error ≤1° (Ku band and below), placing it at an industry-leading level. It is applicable to various phased array antenna architectures and has promising application prospects.

The application discloses a kind of effective Fennel reflection coefficient calculation method based on sea wave spectrometer, first by least square fitting anisotropic quasi-speculum scattering formula, the slope variance component of observation azimuth is obtained;The variation law of the slope variance component with azimuth is fitted with azimuth cosine function, to obtain the total slope variance of the detected sea surface, slope variance component fluctuation rate and sea surface wave propagation direction;Then by the slope variance component along the wave propagation direction and total slope variance, the distribution of the slope variance component perpendicular to the detection azimuth with observation azimuth is obtained;Finally, by calculating the non-standardized correlation coefficient between observation azimuth and the slope variance perpendicular to observation azimuth angle, the 0 degree effective Fennel reflection coefficient of different incident angle beams can be obtained according to quasi-speculum scattering formula, and the effective Fennel reflection coefficient of Ku band at 0 degree incident angle can be obtained by averaging the results of each beam with wind speed.

The present application relates to a kind of low profile composite material strip line antenna unit, Ku band array antenna, belong to radar and communication antenna field.Antenna unit includes polyimide single-sided copper-clad plate, PMI polymethacrylimide foam, polyimide single-sided copper-clad plate, PMI polymethacrylimide foam and polytetrafluoroethylene glass cloth double-sided copper-clad plate, six layers of different thickness plane material are made by bag pressure high temperature gluing.The upper layer polyimide copper-clad layer corrosion octagonal hole is used as the aperture of antenna unit radiation, polytetrafluoroethylene glass cloth double-sided copper-clad layer and metallized via array constitute the radiation cavity of antenna unit, the middle layer polyimide copper-clad plate is used as antenna feeder, and pentagonal patch is stretched into radiation cavity resonance, and electromagnetic wave is radiated through the aperture of upper layer.The present application has the characteristics of light weight, low profile, wide bandwidth, small loss, easy processing and the like by composite material strip line feed.

The utility model belongs to the technical field of filter structures, and particularly relates to a KU-frequency-band low-loss microstrip filter structure design which comprises a machine body and a prompting mechanism, the two ends of the machine body are fixedly connected with connector assemblies, the prompting mechanism is arranged on the connector assemblies, the prompting mechanism comprises an outer cylinder detachably connected to the connector assemblies, and the outer cylinder is arranged on the machine body. The inner side of the outer cylinder is rotationally connected with an inner cylinder, an observation opening is formed in the end, close to the inner cylinder, of the outer cylinder, and a prompt mark is arranged on the surface of the end, close to the outer cylinder, of the inner cylinder. According to the utility model, the inner cylinder and the outer cylinder can move relatively when the joint assembly and the connector are loosened, so that a maintainer can judge whether the joint assembly and the connector are loosened by observing whether a prompt sign is exposed in the observation port or not; and relative rotation between the connector assembly and the connector can be hindered through friction between the outer barrel and the inner barrel, and the loosening situation is reduced.

1. Name of the product in this design: Emergency Call Terminal (KU band). 2. Purpose of this design: For receiving emergency broadcast signals in the Ku band, parsing instructions, and ultimately achieving audio amplification and early warning. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: 3D view 1.

The invention discloses CNTs / rGO / PI composite wave-absorbing foam with a directional aperture structure and a preparation method of the CNTs / rGO / PI composite wave-absorbing foam, and belongs to the technical field of wave-absorbing materials.Graphene oxide, carboxylated multi-walled carbon nanotubes and other raw materials are ultrasonically dispersed into prepared PAAs water and then ultrasonically stirred to be uniform, directional freezing is conducted, then freeze-drying treatment and thermal reduction treatment are conducted, and the CNTs / rGO / PI composite wave-absorbing foam with the directional aperture structure is obtained. The CNTs / rGO / PI composite wave-absorbing foam with the directional aperture structure is obtained by adding the directional aperture structure into the CNTs / rGO / PI composite wave-absorbing foam, the shape and the average internal diameter of the composite wave-absorbing foam are controllable, the density is as low as 0.002-1.2 g / cm < 3 >, the CNTs / rGO / PI composite wave-absorbing foam has an electromagnetic wave absorbing effect at 2-18GHz, the wave-absorbing bandwidth reaches 8.4 GHz when the thickness is 3.6 mm, and the whole Ku wave band and most X wave bands are covered by the CNTs / rGO / PI composite wave-absorbing foam. The composite foam is simple in preparation process, low in cost and suitable for large-scale production.

The application provides a nano-aerogel material with excellent radiation refrigeration and millimeter wave wave transmission performance and a preparation method thereof, the nano-aerogel material is formed by a high-crosslinking-density silicon-containing polymer matrix and a trisilanol ethyl polyhedral oligomeric silsesquioxane through a crosslinking reaction and supercritical fluid drying, the nano-aerogel material has a bimodal nanopore structure composed of small pores and large pores, the porosity is 92% to 94%, and the nano-aerogel material has the radiation refrigeration and millimeter wave wave transmission performance. The nano-aerogel material has a wave transmission rate of at least 99.5% in the Ku band, and even can reach 99.7%, and the passive cooling performance of the nano-aerogel material can reach a delta T of 9.26 DEG C, and the nano-aerogel material has excellent millimeter wave wave transmission performance and radiation refrigeration performance.

The invention belongs to the technical field of preparation and application of wave-absorbing materials, and particularly relates to a preparation method and application of an adjustable reduced graphene oxide broadband wave-absorbing material. The preparation method comprises the following steps: ultrasonically stirring and mixing graphene oxide prepared by Hummers and ultrapure water, freeze-drying the obtained GO suspension, and performing micro-reduction at a certain temperature to obtain the rGO wave-absorbing material. The wave-absorbing performance of the micro-reduced graphene oxide is regulated and controlled by modulating different reduction degrees and different pore sizes, the EAB value of the rGO material can reach 7.98 GHz, the Ku band frequency is completely covered, and the excellent broadband wave-absorbing performance is shown.

This invention proposes a broadband traveling wave suppression metamaterial, wherein the broadband traveling wave suppression metamaterial, a metal connection region, and an aircraft wing trailing edge skin are sequentially connected. The broadband traveling wave suppression metamaterial is disposed at the end of the metal connection region of the aircraft wing trailing edge skin. The impedance of the end of the broadband traveling wave suppression metamaterial near the end of the metal connection region is matched with the impedance of the end of the metal connection region, and the impedance of the broadband traveling wave suppression metamaterial gradually changes steplessly from near to far from the end of the metal connection region. The broadband traveling wave suppression metamaterial of this invention achieves excellent traveling wave suppression performance in the P to Ku bands and is maintenance-free; it solves the pain points of traditional traveling wave suppression materials, such as difficulty in low-frequency traveling wave suppression and high maintenance costs.

The invention provides an active frequency selective surface with polarization independence and angle stability, which comprises a dielectric substrate and cross-shaped metal rings arranged on the dielectric substrate periodically, the tail end of each arm of each cross-shaped metal ring is provided with a notch, each notch is bridged with a PIN diode, and the PIN diode is connected with the dielectric substrate. The cross-shaped metal ring and the four PIN diodes symmetrically arranged on the cross-shaped metal ring jointly form a 90-degree rotational symmetric structure, so that the active frequency selective surface has highly consistent frequency response characteristics for incident electromagnetic waves in different polarization directions; by synchronously controlling the on-off states of all PIN diodes, the resonant frequency of the active frequency selective surface is switched between two frequencies in a Ku wave band, the problem of polarization sensitivity caused by anisotropy of a traditional adjustable structure is fundamentally solved, and excellent polarization independence is achieved.