24results about How to "Improving Impedance Matching Performance" patented technology

The invention discloses a metasurface wave absorber based on a square and round multi-nested structure. The structure is composed of a top metal resonance layer, a dielectric layer and a bottom metal layer. The wave absorber is composed of a periodic unit structure, and a resonance layer of the wave absorber is composed of a split circular ring, a split square ring, a metal wafer and eight chip resistors. The split circular ring is distributed on the outermost periphery of the resonance layer, a certain distance is kept between the split circular ring and the boundary of the resonance unit, and chip resistors with the resistance value of 250 ohms are welded to the four split positions of the circular ring; the split square ring is arranged on the inner side of the circular ring and keeps a certain distance from the circular ring, and 300-ohm chip resistors are welded at four split positions; the inner side of the split circular ring is provided with a metal disc and keeps a certain distance from the square ring. The metasurface wave absorber is low in manufacturing cost and simple in structure, the electromagnetic wave absorption rate can reach 90% or above at 10.15 GHz-20.91 GHz, and the metasurface wave absorber has the very good broadband absorption characteristic.

The invention relates to an ultra-wideband frequency reconfigurable tight coupling dipole array with wide beam scanning. The ultra-wideband frequency reconfigurable tight coupling dipole array comprises a plurality of antenna units, the antenna unit comprises a tight coupling dipole radiation unit, a reconfigurable layer, a wide-angle impedance matching structure, a feed structure and a metal floor; the wide-angle impedance matching structure, the tight coupling dipole radiation unit and the feed structure are sequentially located on the first dielectric plate from top to bottom, and the first dielectric plate is placed perpendicular to the horizontal plane. The reconfigurable layer, the metal floor and the first dielectric plate are vertically arranged in an intersecting mode, and the reconfigurable layer is located above the metal floor. The reconfigurable layer and the double-layer double-sided capacitor loading ring structure are used for achieving the frequency reconfigurable function of the ultra-wideband array, and meanwhile the high radiation efficiency and the large-angle scanning capacity of the ultra-wideband array are effectively guaranteed. In addition, the invention also designs a feed structure containing a capacitor loading short-circuit pin, so that no common-mode resonance in the working frequency band of the ultra wide band is ensured.

The present invention provides a FeNiHo / carbon nanofiber composite absorber and a preparation method thereof, an absorbent material and a preparation method thereof, and belongs to the technical field of electromagnetic wave absorbing materials. The present invention first mixes iron salt, nickel salt, holmium salt and polyvinyl pyrrolidone in a mixed solvent, and electrostatically spins the obtained spinning precursor solution to obtain a nanofiber membrane; the nanofiber membrane is sequentially subjected to pre-oxidation treatment and carbonization treatment to obtain a FeNiHo / carbon nanofiber composite absorber. The FeNiHo / carbon nanofiber composite absorber, paraffin and petroleum ether are mixed, and then pressed and irradiated with ultraviolet light to obtain an absorbing material. The FeNiHo alloy nanoparticles in the composite absorber improve the impedance matching performance and electromagnetic wave attenuation ability of the carbon nanofiber. The obtained absorbing material can achieve the purpose of real-time adjustment of the absorption frequency by irradiation with ultraviolet light.

The invention relates to the field of inorganic nano composite materials, and provides a preparation method of a nitrogen-doped carbon nanotube wave-absorbing material filled with Fe7S8-FeS2. The method aims at solving the technical problems that the dielectric regulation and control mechanism of a transition metal sulfide wave-absorbing material is not clear, the electromagnetic wave absorption frequency band is narrow, and the absorption strength is low. According to the main scheme, the method comprises the following steps: dissolving dicyandiamide and ferric chloride in deionized water, and heating and drying to obtain red powder; annealing the powder to obtain Fe / nitrogen-doped carbon nanotube black powder; after mixing with sulfur powder, annealing again to obtain Fe7S8 / nitrogen-doped carbon nanotube black powder; and finally, mixing and annealing with sulfur powder to obtain the Fe7S8 / FeS2 filled nitrogen-doped carbon nanotube wave-absorbing material. The material shows excellent absorption strength and absorption bandwidth under the condition of low thickness (1.6 mm), the maximum reflection loss is-36.83 dB, and the effective absorption bandwidth is 5.14 GHz (11.9-17.04 GHz). The invention also provides application of the material, namely the material is used as a wave-absorbing material, and is mixed with paraffin or epoxy resin and then coated on the surface of a protected object.

The invention provides a FeCo alloy / graphene foam composite material and preparation and application thereof, the FeCo alloy / graphene foam composite material comprises FeCo alloy particles and graphene foam, and the FeCo alloy particles are loaded on the surface of the graphene foam and embedded between sheet layers and pores of the graphene foam. Different graphene foam contents have great influence on the morphology structure, saturation magnetization intensity, electromagnetic parameters and the like of the product. Along with the increase of the content of the graphene foam, the loading area of the FeCo alloy is continuously increased, and the large-particle FeCo alloy loaded on the graphene sheet is continuously reduced. The saturation magnetization and the magnetic loss capability of the composite material are continuously reduced along with the increase of the content of the graphene foam, and the electrical loss capability is continuously improved.

The invention provides a Fe2. 25Te2 at graphene electromagnetic wave-absorbing material and a preparation method and application thereof.The preparation method comprises the steps that S1, a quartz boat filled with Te blocks is placed on the upstream of a tubular furnace hot area, and the temperature of the hot area is kept at the temperature sufficient to enable Te to be smelted slowly; s2, mixing Fe2O3 powder, fused salt and graphene oxide powder according to a certain mass part ratio, uniformly grinding, thinly paving the mixture in another quartz boat, and placing the quartz boat in the central position of the hot area of the tube furnace; s3, heating the quartz boat in the S1 and the other quartz boat in the S2 at the same time, and carrying out sufficient reaction by using a molten salt assisted chemical vapor deposition technology; and S4, after the reaction in the S3 is completed, naturally cooling to obtain the tetragonal-phase Fe < 2.25 > Te2 (at) graphene broadband electromagnetic wave-absorbing material. The preparation method is simple, convenient and efficient, the product achieves broadband wave absorption through the synergistic effect of the two-dimensional Fe2. 25Te2 nanosheets and graphene, the quality is stable, and performance evaluation is high.

The invention discloses a low-profile ultra-wideband antenna and a working method thereof, and the antenna comprises a radiator which carries out the effective radiation of the antenna at a first frequency band; the antenna feed body and the radiating body are partially projected and overlapped along the direction vertical to the ground plane, and the projected and overlapped parts are mutually coupled to form a coupled feed structure; the antenna feed body is used for transmitting energy to the radiator and serves as the radiator to provide impedance matching in a second frequency band; the coupled feeding structure is used for carrying out coupled feeding, realizing impedance matching of the first frequency band and expanding the impedance bandwidth of the first frequency band; the branch antenna is used for providing radiation in a third frequency band and assisting the radiation of the parasitic antenna in a fourth frequency band; the parasitic antenna provides radiation in a fifth frequency band. The antenna is used for realizing ultra-wide frequency band coverage in a limited space, and good radiation performance and impedance matching effect can be provided in each frequency band.

The invention discloses an impact-resistant structure wave-absorbing material and a preparation method thereof, and belongs to the technical field of wave-absorbing materials. The impact-resistant structure wave-absorbing material comprises a rubber sheet and a light structure wave-absorbing layer which are stacked in sequence. And the raw materials of the rubber sheet comprise rubber and hollow glass beads filled in the rubber. By filling the hollow glass beads, the impedance matching property between the material and air is remarkably improved, so that electromagnetic waves enter the wave-absorbing layer to the greatest extent to generate loss, and the wave-absorbing property of the material is effectively improved; the rubber sheet has good flexibility and impact resistance, and has excellent impact resistance even under the condition that the thickness is 0.4-1.2 mm; due to the fact that the hollow glass beads are added, the surface density of the rubber sheet is only 0.3-0.8 kg / m, the rubber sheet is combined with the light structure wave-absorbing material, the overall weight is light, and the maneuverability of maneuvering equipment is improved. The impact-resistant structure wave-absorbing material not only has good electromagnetic wave absorption performance and impact resistance, but also is light in weight and high in environmental adaptability, and the preparation process is simple.

The utility model relates to the technical field of antenna structures, and provides a broadband multi-branch dual-frequency antenna and radio frequency equipment, and the broadband multi-branch dual-frequency antenna comprises a dielectric substrate; the antenna main body unit is arranged on the dielectric substrate, and the antenna main body unit comprises a low-frequency branch knot and a high-frequency branch knot which are connected with each other; the grounding unit is connected with the antenna main body unit, and a gap structure is arranged between the grounding unit and the antenna main body unit; the first parasitic branch knot is connected with the grounding unit and is adjacent to the antenna main body unit, the bandwidth of the broadband multi-branch-knot dual-frequency antenna is expanded, and the matching characteristic of the antenna is improved.

The utility model relates to the technical field of antennas, in particular to a broadband center-fed antenna matching coil, which comprises a magnetic core, a first cable and a second cable. The first cable and the second cable are both wound on the magnetic core, an inner core of the first cable and an inner core of the second cable are connected in series, and the winding turn number ratio of the first cable to the second cable is 3: 6 to 4: 6; the impedance of the first cable ranges from 45 ohms to 55 ohms, the impedance of the second cable ranges from 70 ohms to 80 ohms, the length of the first cable ranges from 360 mm to 400 mm, and the length of the second cable ranges from 485 mm to 525 mm. The broadband center-fed antenna matching coil provided by the utility model is used for overcoming the defects of limited frequency band and high standing-wave ratio of the existing matching coil.

The invention discloses a cloud-shaped pomelo peel biomass derived carbon broadband absorbing material which has an absorption wave range of-40 dB to-60 dB and a wide absorption bandwidth of 6-8 GHz. The invention also discloses a preparation method of the broadband absorbing material. The preparation method comprises the following steps: firstly, selecting waste shaddock peel and preparing cloud-shaped biomass derived carbon through heat treatment; then cobalt nitrate hexahydrate and zinc nitrate hexahydrate are mixed according to a certain mass ratio, hydrothermal treatment is carried out, Co / ZnO is promoted to grow on the surface of biomass-derived carbon in situ, and the biomass-carbon-based microwave absorbing material with broadband absorption bandwidth and excellent impedance matching characteristics is prepared. The method provides a new technical path for the development of the biomass carbon composite microwave absorbing material. The preparation process is simple, environment-friendly and low in cost, has good repeatability and consistency, and is suitable for large-scale production.

The present invention discloses a broadband high-gain WiFi omnidirectional antenna, comprising a dielectric substrate, wherein a feeding point is provided on the upper surface of the dielectric substrate, and a sawtooth radiation component and a wave radiation component are arranged on the left and right sides of the feeding point, wherein the wave radiation component comprises a strip radiation patch and a rectangular radiation patch, wherein the rectangular radiation patch is connected to one end of the strip radiation patch; the strip radiation patch is formed with a wave radiation section in a planar wave structure; and two groups of first bent radiation patches and two groups of second bent radiation patches are provided on the lower surface of the dielectric substrate, wherein the sawtooth radiation component is respectively connected to the two groups of first bent radiation patches through two first metal through holes preset in the dielectric substrate, and the wave radiation component is simultaneously connected to the two groups of second bent radiation patches through a first metal through hole preset in the dielectric substrate.

The invention discloses a light-emitting diode well layer control method and system based on ESD impedance matching, and the method comprises the steps: adjusting the doping concentration of an N-type well layer and the doping concentration of a P-type well layer, changing the conductivity and carrier flow of the well layers, so as to improve the impedance of an ESD protection device, and adjusting the depth and width of the well layers, so as to improve the ESD protection device. The invention provides a light-emitting diode well layer control system based on ESD impedance matching to further optimize the impedance of an ESD protection device, the breakdown voltage and the leakage current in parameters of the ESD protection device can be optimized by verifying the influence of a well layer on current carrier flow and impedance so as to achieve the optimal impedance matching, and in addition, the invention further provides a light-emitting diode well layer control system based on ESD impedance matching. Comprising a doping concentration adjusting module, a well layer verification module, a carrier dynamic module and an impedance matching module, can automatically adjust and optimize the well layer structure, and meets the requirements of the IEC 61000-4-2 standard.

The radio frequency packaging structure comprises a ceramic substrate, a bottom metal layer, a coplanar waveguide transmission line, a left side metal layer and a right side metal layer, the bottom metal layer is tightly attached to the bottom of the ceramic substrate, and the coplanar waveguide transmission line is tightly attached to the top of the ceramic substrate; the left side metal layer is tightly attached to the left side part of the ceramic substrate, and the right side metal layer is tightly attached to the right side part of the ceramic substrate; the coplanar waveguide transmission line comprises a first ground electrode, a second ground electrode and a signal electrode which are arranged in parallel; the first end of the signal electrode is of an isosceles trapezoid transition structure, and the size of the transition structure is gradually reduced along with approaching the modulator chip. According to the radio frequency packaging structure of the lithium niobate electro-optical modulator disclosed by the invention, the bandwidth of the packaged lithium niobate modulator can be improved on the premise that the bandwidth of a chip is not improved, and the loss in device packaging is reduced.

The utility model discloses a Mini Fakra line end connector. The Mini Fakra line end connector comprises a plug assembly and a socket assembly which are connected in a pluggable mode. The plug assembly comprises a first shell and a first terminal assembly fixedly arranged in the first shell; the socket assembly comprises a second shell and a second terminal assembly fixedly arranged in the second shell, a buckling structure is arranged at the top of the plug assembly, and a supporting part of the buckling structure is integrally formed at the top of the first shell and is close to the wiring end of the plug assembly. Compared with the prior art, a larger movement gap does not need to be reserved between the barb and the non-return surface, the plugging distance between the plug assembly and the socket assembly can be smaller, and the size of the barb can be larger, so that the connection stability of the plug assembly and the socket assembly is effectively improved; moreover, the buckling gap is reduced, the relative movement of the male terminal and the female terminal is reduced, the wear is reduced, the service life of the connector is prolonged, and the impedance matching performance and the high-frequency and high-speed signal transmission performance are further improved.

The invention discloses a ZIF-67 derived Co@C / RGO double-layer absorbing film and its preparation method and application, comprising the following steps: adding cobalt nitrate hexahydrate, 2-methylimidazole and polyvinyl pyrrolidone to methanol, aging after stirring to obtain aging solution; adding copper chloride and graphite oxide sol to methanol, ultrasonic dispersion to obtain graphene oxide dispersion; adding graphene oxide dispersion to aging solution, vigorously stirring to obtain a mixed solution; filtering the mixed solution to obtain a suction filtration membrane attached with ZIF-67 / GO double-layer membrane, drying to obtain a dried ZIF-67 / GO double-layer membrane; high temperature treatment of the dried ZIF-67 / GO double-layer membrane to obtain a ZIF-67 derived Co@C / RGO double-layer absorbing film. The present invention solves the problem that ZIF-67 is difficult to form a uniform film due to strong electrostatic interaction and mutual repulsion, and improves the electromagnetic wave absorption performance of existing absorbing materials.

The present invention discloses a digitally controlled dual-frequency low-noise amplifier circuit with differential output, which includes an input impedance matching network, an amplifier stage, a differential output stage and a load stage. Compared with the traditional dual-frequency low-noise amplifier with independent channels, the present invention shares a common-gate amplifier with source negative feedback, which improves the power gain of the circuit, and also significantly improves the chip area, cost and circuit utilization. Compared with the traditional dual-frequency low-noise amplifier with independent channels, the present invention uses a switch to control the shutdown of the bias voltage, which reduces the design difficulty and increases the design flexibility, so that the circuit can obtain good noise performance and impedance matching effects in various frequency bands. The present invention effectively reduces the power consumption of the system by controlling the selection of the frequency band path through the switch.

The invention relates to a high-power large-angle full-plane scanning dual-polarization phased-array antenna unit and array, and belongs to the technical field of antennas. The antenna unit comprises a metal radiator, a reflection floor, a cross matching feed panel, a periodic medium matching layer, a common-mode suppression column and a radio frequency connector. The metal radiator is of a cross structure, gap grooves are reserved in the four edges of the metal radiator, exponential radiation edges are arranged above the grooves, and a semicircular matching circle is reserved in the middle of each groove. The reflection floor is positioned below the metal radiator; the cross matching feed panel is embedded in the slot groove of the metal radiator, and a printed circuit is arranged on the cross matching feed panel to serve as an antenna feed line; the medium matching layer is positioned above the metal radiator; the common-mode suppression columns are located at four corners of the reflection floor; and the radio frequency connector passes through the reflection floor to be connected with the cross matching feed panel and is used for feeding the whole antenna unit. The array includes a plurality of antenna units. According to the invention, the problem of large-angle full-plane scanning is solved, and the good full-plane + / -60-degree scanning characteristic is realized.

This invention belongs to the field of electromagnetic wave absorbing materials technology, specifically relating to a nickel-boron-doped cobalt-based layered carbon absorbing material and its preparation method. This invention utilizes a cobalt-based boron imidazole precursor framework as a template, and forms a two-dimensional layered layered double hydroxide (LDH) through a chemical oxidation etching process using nickel ions. This LDH is then subjected to high-temperature reduction to obtain the nickel-boron-doped cobalt-based layered carbon material. This material leverages the unique properties of two-dimensional materials to achieve high impedance matching, allowing electromagnetic waves to enter the absorber at a significant rate. Furthermore, the material's excellent dielectric polarization and magnetic coupling attenuate the electromagnetic waves entering the absorber. The material achieves a minimum reflection loss of -60.1 dB and a maximum effective absorption bandwidth of 6.24 GHz, giving it excellent electromagnetic wave absorption capabilities. The preparation method of this invention is simple and easy to mass-produce.

This invention discloses a graphene aerogel surface microwave absorbing material supported on Fe / N co-doped hollow carbon nanospheres and its preparation method. First, a reduced graphene oxide aerogel is prepared using graphene oxide as a raw material. Then, hollow Fe3O4 magnetic nanoparticles are prepared via a hydrothermal method using FeCl3·6H2O and ammonium acetate as raw materials. Finally, Fe3O4 / PPy / reduced graphene oxide aerogel is prepared by in-situ polymerization, and the graphene aerogel supported on Fe / N co-doped hollow carbon nanospheres is obtained through high-temperature heat treatment. The graphene aerogel surface microwave absorbing material supported on Fe / N co-doped hollow carbon nanospheres of this invention exhibits excellent dielectric and magnetic losses. Simultaneously, the magnetic Fe nanoparticles in the material can effectively convert electromagnetic wave energy, achieving excellent microwave absorption performance, and showing great potential in next-generation cutting-edge advanced nanocomposite materials.

The invention provides a design method of a multilayer HTCC ceramic RF SIP packaging tube shell and a packaging device, relates to the technical field of RF SIP packaging, and aims to comprehensively optimize packaging design from multiple targets of signal integrity, heat dissipation performance, mechanical reliability and the like by dynamically optimizing the number of layers and the thickness of a multilayer stacked structure so as to avoid conflicts caused by single performance optimization. Meanwhile, based on the design of the gradient microstrip line, the impedance matching performance of radio frequency signals is remarkably improved, signal reflection and transmission loss are reduced, and the antenna is suitable for high-frequency signal transmission requirements. Sensitivity analysis and correction factors are introduced through trial assembly feedback, the deviation between simulation modeling and actual performance is gradually reduced, and efficient and accurate multi-time updating optimization is achieved. The final packaging tube shell design ensures excellent signal integrity, heat dissipation capability and structural reliability, and provides a systematic solution for modern high-frequency and miniaturized packaging.

The invention discloses an S-C wave band heat-resistant wave-absorbing material and a preparation method thereof, and relates to the technical field of S-C wave band wave-absorbing materials. The S-C wave band heat-resistant wave-absorbing material is prepared from ZrO2, Ta2O5 and a TaC nanocrystal, wherein the ZrO2 and the Ta2O5 are The preparation method comprises the following steps: S1, preparing ZrTa MOF powder by adopting a hydrothermal method; s2, the ZrTa MOF powder is subjected to two times of charring fast firing treatment, and the ZrTa / C composite material is obtained. According to the invention, ZrTa MOF is taken as a precursor, the ZrTa MOF is burnt twice under the power supply voltage of 26-30V, the nanoscale ZrTa / C composite wave-absorbing material is rapidly prepared, a novel wave-absorbing material which contains ZrO2, Ta2O5 and TaC nanocrystals and is resistant to high temperature and capable of effectively absorbing waves is obtained, and further, the electromagnetic parameters of the wave-absorbing material are improved by introducing Ta, so that S-waveband wave absorption is realized.

The invention discloses a low-profile-based magnetoelectric dipole antenna and an optimization method, and the antenna is characterized in that a connector inner core is fixedly arranged on a reflection plate, and the connector inner core is connected with a feed structure; the feed structure comprises a first feed strip and a second feed strip, and the second feed strip comprises a first strip, a second strip, a third strip and a fourth strip; a first magnetic dipole, a second magnetic dipole, a third magnetic dipole and a fourth magnetic dipole are fixedly arranged on the reflecting plate, the first magnetic dipole is connected with the first electric dipole, the second magnetic dipole is connected with the second electric dipole, the third magnetic dipole is connected with the third electric dipole, and the fourth magnetic dipole is connected with the fourth electric dipole. The low-profile design enables the antenna to be more compact and light, the application range of the antenna is widened, the overall size and weight of equipment are reduced, the stability of the antenna is enhanced, the influence of wind resistance and mechanical vibration on the antenna is reduced, and therefore the reliability of the antenna is improved, and the service life of the antenna is prolonged.

The utility model provides a circularly polarized ultra-wideband microstrip patch antenna based on a metasurface. The circularly polarized ultra-wideband microstrip patch antenna based on the metasurface comprises a dielectric substrate I, low-loss dielectric foam, a dielectric substrate II, a metal ground layer, the metasurface, a slotted circular patch, a metalized through hole and a feed port, the slotted circular patch is arranged on the upper surface of the dielectric substrate I in parallel, the low-loss dielectric foam is arranged between the dielectric substrate I and the dielectric substrate II, and the metasurface is arranged on the upper surface of the dielectric substrate II in parallel; the metal ground layer is located on the lower surface of the first dielectric substrate, four rectangular grooves are etched in the metal ground layer, the metalized through hole is used for connecting the slotted circular patch and the metal ground layer, and the metalized through hole forms a feed port through a coaxial line. According to the ultra-wideband circularly polarized antenna, ultra-wideband circularly polarized radiation is realized through a simple planar structure, and the ultra-wideband circularly polarized antenna has the characteristics of low profile and small size, and is convenient for further processing and integration.