159 results about "Axial ratio bandwidth" patented technology

The invention discloses a circular polarized antenna with a wide wave beam width and a small size. The antenna comprises a square paster; two notch grooves of an open circuit of a terminal are arranged on the square paster, wherein the two notch grooves are mutually orthogonal; the paster is fixed on a square grounding reflecting surface by a coaxial line. And four short-circuit columns of the open circuit of the terminal are arranged on the reflecting surface, so that the size of the reflecting surface is reduced. According to the invention, a signal feeding technology is utilized to excite the two orthogonal notch grooves to work in a circular polarization mode. According to the invention, an impedance bandwidth reaches 19%, wherein a standing-wave ratio is less than 2; and a 3d axial ratio bandwidth reaches 3.8%. In an axial ratio bandwidth, a 3d B wave beam width reaches a value by adding 101.4 degrees with 1.4 degrees or subtracting the 1.4 degrees from the 101.4 degrees as well as a gain reaches a value by adding 5.76dBi with 0.18dBi or subtracting the 0.18dBi from the 5.76dBi. The circular polarized antenna has advantages of compact antenna dimension, light weight, low cost and easy manufacture. Especially, the circular polarized antenna has advantages of good impedance bandwidth, wide radiation wave beam, and high gain. Therefore, the circular polarized antenna can be widely applied to satellite communication and traffic navigation.

The invention belongs to the technical field of design and manufacture of millimeter-wave circularly-polarized antennas, aims to solve the problem of difficulty in integration of broadband, high efficiency and arraying of existing millimeter-wave circularly-polarized antennas, and provides a broadband circularly-polarized panel array antenna. The broadband circularly-polarized panel array antenna has the advantages that a novel 90-degree phase delay line is used for feed of a cross recess, four parasitic patches added above the cross recess are used for improving antenna unit gain and 3dB axial ratio bandwidth, and the designed 90-degree phase delay line has three independent branches which are used for phase delay, amplitude compensation and matching adjustment respectively; a group of short-circuit metal holes are designed beside a strip line to effectively inhibit spreading of a TEM (transverse electromagnetic) mode outside a feed network area, unit cross coupling is reduced greatly, and arraying performance is guaranteed; the antenna made of a multilayer PCB (printed circuit board) has the advantage of low cost and is applicable to millimeter-wave large-scale circularly-polarized arraying, and the problem of difficulty in integration of circularly-polarized antenna efficiency and the axial ratio bandwidth on millimeter-wave frequency bands is solved.

The invention relates to an antenna which comprises an upper-layer microstrip antenna, a lower-layer microstrip antenna and a baffle board, wherein the upper-layer microstrip antenna and the lower-layer microstrip antenna are overlapped and then fixed on the baffle board through screws. The double-frequency antenna provided by the invention is easy to realize and has small volume, favorable axial ratio bandwidth and low elevation gain.

The invention discloses a dual-polarized multi-system compatible antenna which comprises an upper-layer circular capacitance loading metal patch, a monopole metal column, an upper-layer medium baseplate, a first short-circuit pin, a second short-circuit pin, an annular metal patch, an intermediate-layer first medium baseplate, L-shaped probes, an intermediate-layer second medium baseplate, a metal floor, a bottom-layer medium baseplate and a bottom-layer Wilkinson power divider, wherein the Wilkinson power divider is connected with the two L-shaped probes which are orthogonal mutually for performing coupling feed on the annular metal patch, the outer edge of the annular metal patch is circular, the inner edge of the annular metal patch is elliptical, the ratio of a long shaft to a short shaft of an ellipse is regulated, and then the axial ratio performance of the antenna can be regulated; and the upper-layer circular capacitance loading metal patch, the monopole metal column, the first short-circuit pin and the second short-circuit pin constitute a capacitance and inductance loading monopole antenna by inductance loading, thereby effectively reducing the size of the antenna. The antenna has the characteristics of small size, large axial ratio bandwidth, large impedance bandwidth, compact structure and the like.

The invention discloses a circularly-polarized microstrip antenna. The circularly-polarized microstrip antenna comprises an upper dielectric substrate, a middle dielectric substrate, a prepreg, a lower dielectric substrate, a radiation patch, a metal through hole column and a connecting structure, wherein the radiation patch is positioned on the upper surface of the upper dielectric substrate, and is used for realizing circular polarization performance; the prepreg is positioned between the middle dielectric substrate and the lower dielectric substrate, and is used for adhering the middle dielectric substrate and the lower dielectric substrate; the metal through hole column penetrates through corresponding through holes in the middle dielectric substrate, the prepreg and the lower dielectric substrate so as to form a substrate integrated waveguide SIW cavity; a first coupling gap is formed in the middle dielectric substrate; the lower dielectric substrate is provided with a second coupling gap and a strip-shaped feeder line; and the connecting structure is used for leading out the feeder line so as to be connected with an external system. According to the antenna, the circular polarization axial ratio bandwidth and gain are obviously improved, the manufacturing precision is high, and the processing and device cost is low.

The invention discloses a high-gain dual-frequency circularly polarized antenna based on a metasurface. The working frequency bands are a K wave band and a Ka wave band. A metal layer of the antenna comprises a micro-strip ring feeder line, a grounding plane with a cross slot and a metasurface. The micro-strip ring feeder line at the lowest position is coupled with the slotted grounding plane at the middle position. The electromagnetic wave energy is coupled to the metasurface of the uppermost layer and is radiated out. The sequential rotation structure of the micro-strip ring feeder line cangenerate a phase difference of 90 degrees so as to excite circular polarization. According to the feed structure, a wide axial ratio bandwidth can be realized; the metasurface can influence the axialratio bandwidth and gain of high and low frequency bands; the gain of the antenna in two frequency bands is greater than 5dBic; and the single-port feed dual-frequency circularly polarized antenna hasgood radiation characteristics in two frequency band bands, and is compact in structure and easy to process, so that antenna has a good application prospect in a wireless communication system.

The invention discloses a broadband circularly-polarized radio frequency identification (RFID) reader antenna. The broadband circularly-polarized RFID reader antenna comprises a metal grounding plate, a driving radiation unit, a spurious radiation unit, a feed coaxial line, a metal support pillar and a feed network, wherein the driving radiation unit, the spurious radiation unit and the metal grounding plate have a cascade structure; the metal support pillar is fixedly arranged on the metal grounding plate; the spurious radiation unit and the driving radiation unit are fixedly arranged on the metal support pillar sequentially; and the feed coaxial line and the feed network are electrically connected with the driving radiation unit. According to the broadband circularly-polarized RFID reader antenna, the driving radiation unit is excited by the feed network, and the spurious radiation unit is subjected to coupled feeding by the driving radiation unit; operating modes of the two radiation units are the same, and two resonant frequencies are approximate, so that double-humped resonance is formed, and the work bandwidth of the antenna is increased; and the spurious radiation unit achieves an effect of a director to increase the gain of the antenna, so that the aim of providing an electromagnetic wave with high gain, large impedance bandwidth, large axial ratio bandwidth and large axial ratio beamwidth is fulfilled.

A slotted waveguide antenna for receiving circularly polarized waves capable of improving impedance matching, an axial ratio and an axial ratio bandwidth by additionally forming a dielectric plate between a conductive plate having waveguides and a polarizer of an uppermost layer is disclosed. The slotted waveguide antenna for reception of circularly polarized waves, which includes a lower conductive plate and an intermediate conductive plate which are coupled to each other to have a feeding line and a waveguide to which satellite frequency signals are transmitted and an upper conductive plate which is coupled to an upper portion of the intermediate conductive plate and has a plurality of cavities and slots to communicate with the waveguide so as to transmit and receive satellite frequency signals, includes a polarizer with strip conductors for converting linearly polarized waves into circularly polarized waves and matching stubs which are formed at an upper portion of the upper conductive plate, and a dielectric plate which is disposed between the upper conductive plate and the polarizer (100) to perform impedance matching with space impedance.

The invention relates to an array antenna which comprises a microstrip antenna array, a baffle board and a phase-shift feed network, wherein the microstrip antenna array is located on the front of the baffle board and the phase-shift feed network is located on the back of the baffle board. The array antenna provided by the invention has a compact structure, strong anti-jamming capability, favorable axial ratio bandwidth and low elevation gain.

The invention relates to a broadband low sidelobe circularly polarized array antenna loaded with a super surface. The broadband low sidelobe circularly polarized array antenna comprises the super surface, a radiation patch, a feeding network, a dielectric layer 2, a dielectric layer 1 and a grounding plate which are orderly stacked from top to bottom, and the super surface is loaded on the radiation patch. The impedance bandwidth and axial ratio bandwidth of the antenna are greatly increased. A transmission line is connected in series at the center of a radiation side of the radiation patch. The input impedance characteristics of the antenna near a resonant frequency can be improved, so that the impedance change tends to be stable and is a pure real number, and therefore, the subsequent arraying is facilitated. According to the invention, a 4-unit sequential rotary feed network is simplified into a 2-unit network, a one-to-four unequal power divider is used in the X direction, the axial ratio of the antenna can be optimized, and the sidelobe levels of XZ planes of the antenna can be reduced.

The invention discloses a broadband directional circularly polarized antenna applied in a wireless communication system. The broadband directional circularly polarized antenna comprises a dielectric substrate, a metal back cavity and a metal floor; upper and lower surfaces of the dielectric substrate have fan-shaped symmetrical dipole metallic patches; rotation parasitic metallic patches are distributed between the fan-shaped symmetrical dipole metallic patches; the fan-shaped symmetrical dipole metallic patches and the rotation parasitic metallic patches are symmetrically distributed around the center; the fan-shaped symmetrical dipole metallic patches and the rotation parasitic metallic patches rotate 90 degrees around the center in order; phase shifting rings of the connected fan-shapedsymmetrical dipole metallic patches on the upper and lower surfaces of the dielectric substrate are connected to an inner core and an outer sheath of a coaxial line; and the coaxial line passes through the floor and is connected with an SMA connector. The invention is simple in structure, is easy to process, and has wide axial ratio bandwidth and impedance bandwidth; a directional diagram is relatively stable in the common frequency band, so that the broadband directional circularly polarized antenna can be used for a wide-band wireless communication system and can reduce the antenna complexity of the communication system.

The invention belongs to the communication and navigation technology field, and concretely relates to a miniature three-frequency dual-circular-polarized antenna. A fixing through hole and a fastening bolt are disposed coaxially in a plumb central line of an upper-layer microstrip patch antenna, a middle-layer microstrip patch antenna, a lower-layer microstrip antenna and a bottom-layer feed network of the antenna. Axes of three first short circuit metalized through holes and the axis of a first feed hole are on the same cylindrical surface with the axis of the fixing through hole being an axis, and the first short circuit metalized through holes and the first feed hole are uniformly distributed on the cylindrical surface in a circumferential manner. The middle-layer microstrip patch antenna is provided with a second feed point. Axes of three second short circuit metalized through holes and the axis of a second feed hole are on the same cylindrical surface with the axis of the fixing through hole being an axis, and the second short circuit metalized through holes and the second feed hole are uniformly distributed on the cylindrical surface in a circumferential manner. The aperture of each first short circuit metalized through hole is equal to the external diameter of a first medium sleeve. The aperture of each second short circuit metalized through hole is equal to the external diameter of a second medium sleeve. The good impedance bandwidth, the good axial ratio bandwidth and the high gain performance are guaranteed, and also miniature and light demands of the size of the antenna are guaranteed.

The invention provides a millimeter-wave low-profile broadband circularly-polarized slot-fed dipole antenna array. The millimeter-wave low-profile broadband circularly-polarized slot-fed dipole antenna array comprises an antenna radiator, parasitic patches, a broadband SIW sequential rotating feed network, a three-layer dielectric substrate and metalized through holes, wherein the radiator is arranged on the upper surface of the top dielectric substrate, and the parasitic patches are arranged around the radiator; the broadband SIW sequential rotation feed network is arranged on the bottom layer and the middle layer of the antenna; and the metalized through holes are positioned at the peripheries of the top-layer radiator and the parasitic patches. On the basis of a common circularly-polarized magnetoelectric dipole antenna structure, the chamfered parasitic patches are introduced to the periphery of the dipole antenna, so the structure realizes the characteristic of broadband circular polarization while having a low profile. Meanwhile, sequential rotation feed is utilized at the lower layer of a unit, so the axial ratio bandwidth of the antenna array is expanded. The antenna is small in physical size, low in profile and suitable for 5G millimeter wave circular polarization communication.

The invention discloses a circularly polarized differential feed antenna, comprising a radiation patch on the upper surface, two L-shaped feed panels, and a horizontal substrate on the lower surface, wherein the upper radiation patch comprises a first lower radiation patch and a second upper radiation patch which are spaced by a certain distance by an isolation foam; the first radiation patch is larger than the second radiation patch, two L-shaped feed panels are directly connected with the first radiation patch in the radiation patch on the upper surface, each L-shaped feed electrode panel is respectively connected with the horizontal substrate on the lower surface and an SMA connector by a probe, and the L-shaped feed panels are excited by a pair of differential signals. The impedance bandwidth and the axial ratio bandwidth are widened and the lower-level crossed polarization and stable direction diagram and gain can be seen on the work frequency band. The scheme can be used in the more and more popular radio frequency differential circuit and system.

The invention discloses a water medium resonator antenna with polarization and directional diagram reconfigurability. The water medium resonator antenna comprises a medium container, medium supportingcolumns, a feed probe, a coaxial feed port and a metal floor; two chambers are formed in the medium container, hole valves are arranged at the tops of the two chambers, high dielectric constant medium liquid is injected from the hole valves to achieve circular polarization of the antenna in different directions of turning, and if no liquid is injected, the antenna is linearly polarized; the medium container is located above the metal floor and supported by the medium supporting columns, so that an air layer is formed between the medium container and the metal floor, a part of the feed probe extends into the medium container for feeding and is located between the two chambers, and the other part of the feed probe penetrates downwards through the metal floor and then is connected with the coaxial feed port. The antenna has the advantages of polarization and directional diagram reconfigurability, high radiation efficiency and wide impedance bandwidth. The antenna has the advantage of wide axial ratio bandwidth when the antenna is circularly polarized, and can be applied to a satellite communication system.

The application relates to an antenna unit, an antenna array and a road side unit. The antenna unit comprises a first medium plate and a second medium plate. The first medium plate comprises an upper surface, a lower surface and a radiation paster. The radiation paster is pasted on the upper surface or the lower surface of the first medium plate. The second medium plate comprises a first surface which is opposite to the lower surface in arrangement and a second surface which is back to the first surface. The first surface is a plate made of conductive material, and the first surface is provided with multiple coupling gaps used for formation of a multi-feed-point feed mode. The second surface is provided with a power divider. Compared with a conventional single-layer square paster antenna unit, impedance bandwidth and axial ratio bandwidth of the antenna are enhanced by the antenna unit via the mode of the double-layer medium plates, and a circular polarization characteristic is quite stable. Besides, the feed mode of double-feed-point gap coupling is adopted, and coupling feed is performed on the metal radiation paster arranged at the top layer via the power divider arranged at the bottom layer so that radiation is enabled to be more stable.

The invention discloses an optimum design method of a circular polarization triangular micro-strip antenna based on a characteristic module theory. The optimum design method includes steps of 1 obtaining the optimum side length a of a triangular patch; 2 optimally designing the gap size of the patch; and 3 optimally designing the feed position. The single feed point circular polarization triangular micro-strip antenna is simple in structure and easy to process and has satisfactory impedance and axial ratio bandwidth. The optimum design method can explain the working principle of the circular polarization triangular micro-strip antenna in the aspect of the physical concept, designs the determined antenna feed position and working frequency, and greatly improves the efficiency compared with manual antenna parameter adjustment processing by aid of High Frequency Structure Simulator (HFSS) simulation software.

The invention discloses a dual circularly polarized array antenna. The dual circularly polarized array antenna comprises a first radiation unit, a second radiation unit, a third radiation unit, a fourth radiation unit and a dual circularly polarized feeding network, wherein the first radiation unit, the second radiation unit, the third radiation unit and the fourth radiation unit are used for generating circularly polarized waves in a mode of ordered rotation sequence and are arranged in two lines and two rows, the dual circularly polarized feeding network is provided with two input ports and four output ports, feeding with equal amplitude and unequal phases is provided for the first radiation unit, the second radiation unit, the third radiation unit and the fourth radiation unit, excitation is input from the two input ports of the feeding network, so that the four output ports provide two different excitation phase distributions. By the antenna structure, the dual circularly polarized wave can be effectively generated, the dual circularly polarized wave with high gain, low cross polarization, relatively wide axial ratio bandwidth and relatively high isolation can be achieved in a millimeter wave band with relatively high frequency, and the dual circularly polarized array antenna has the characteristics of compact structure and lightness and is easy to integrate with a radio frequency front-end circuit.

The invention discloses a sequential phase feed circular polarization dielectric resonant antenna array which is composed of n dielectric resonators, a four-rotation feed network, Wilkinson power distributors, a dielectric substrate, coaxial feeding, metal probes and strip lines. The N dielectric resonators form an array on the dielectric substrate. The feed network is composed of one four-rotation feed network and four one-to-two Wilkinson power distributors which are located on the central back of the dielectric substrate. The coaxially transmitted energy is fed to the two frequency dividersvia the feed network and coupled to the orthogonally arranged strip lines on the side wall of the dielectric resonator by the two metal probes arranged at the output end of the frequency divider. Thearray can realize narrower main lobe radiation pattern width, higher gain, wider impedance bandwidth and axial ratio bandwidth, thereby enabling the antenna to have further excellent and stable circular polarization performance and better meet the index requirements of modern communication technology for the circular polarization communication system.

The invention discloses a dual-frequency dual-circularly polarized microstrip array antenna with wide axial ratio bandwidth. The microstrip array antenna comprises a monolayer microwave dielectric substrate, four dual-frequency linearly polarized radiation patches with working frequencies of f1 and f2, and a dual-frequency shared microstrip power dividing network. Wherein, the dual-frequency linearly polarized radiation patch with the working frequency f1, f2 is uniformly distributed on the circumference with the point O as the center; The dual-frequency shared microstrip power dividing network comprises two Wilkinson power dividers, two dual-frequency shared 90-degree phase shifters composed of microstrip lines, and one dual-frequency shared 180-degree phase shifter. The invention effectively increases the dual-frequency circular polarization axial ratio bandwidth, and can be conveniently expanded into a high-gain array with a larger aperture, adopts a single-layer dielectric plate, and the array element is a single unit, the structure is simple, the profile is low, and realization is easye.

The invention belongs to the technical field of communication and navigation and in particular relates to a multi-frequency navigation terminal antenna. A top-layer feeding point is arranged at the center of a first-layer micro-strip patch; a central feeding hole is vertically formed in the top-layer feeding point; a first feeding point is arranged at a second-layer micro-strip patch; a first feeding hole is vertically formed in the first feeding point; a second feeding point is arranged at a third-layer micro-strip patch; a second feeding hole is vertically formed in the second feeding point; a third feeding point is arranged at a fourth-layer micro-strip patch. The antenna also comprises first short circuit metallized via holes and second short circuit metallized via holes which are used for eliminating coupling influence of feeding probes in all the feeding holes. The multi-frequency navigation terminal antenna disclosed by the invention can cover L band and S band of first-generation Beidou, B1 band and B3 band of second-generation Beidou and L1 band of a GPS (Global Positioning System); the demands on minimization and lightness of antenna size are met while good impedance bandwidth, axial ratio bandwidth and high-gain performance can be guaranteed.

The invention discloses a circularly polarized planar substrate integrated magnetoelectric dipole antenna and an array thereof. The antenna comprises a top metal layer, a first dielectric layer, a middle metal layer, a second dielectric layer, a third dielectric layer and a bottom metal layer which are sequentially arranged from top to bottom. A pair of L-shaped patches which are rotationally andsymmetrically arranged are arranged at the center of the top metal layer; the middle metal layer is a grounding layer, and a rectangular groove is etched in the middle metal layer; and the pair of L-shaped patches and the middle metal layer are electrically connected through a pair of metallized semi-blind holes penetrating through the first dielectric layer. The antenna carries out feeding through the low-profile microstrip feed structure, can be conveniently expanded into an array, and does not need to additionally arrange a dielectric layer to design a feed network. The ground antenna provided by the invention can obtain about 50% of impedance bandwidth, about 8% of 3dB axial ratio bandwidth and wider 3dB axial ratio beam width, and can realize direct integration with a millimeter waveradio frequency front-end circuit.