121results about How to "Simple feed structure" patented technology

When configuring a film antenna for receiving a circular polarized wave, at least one loop antenna is formed on a transparent plastic film and, at the same time, a non-powered element constituted by a wire-shaped conductor independent from the antenna conductor configuring the loop is arranged near this loop antenna. The non-powered element arranged on the side of the loop antenna is configured by a first part and a second part. The first part is made close to the loop antenna in a substantially parallel state. When a monopole antenna is used in place of the loop antenna, by combining this with a wire-shaped conductor orthogonal to this, it becomes possible to receive a circular polarized wave by a configuration providing a power transfer part between the two. It is also possible to configure a composite antenna by mounting another antenna on the transparent plastic film. This antenna can be used as an antenna of a navigation system.

This invention relates to a board-shaped wideband dual polarization antenna whose feeding structure is simplified. Dipole antennas are prepared on both front and rear surfaces of a printed circuit board, and an electric signal is fed to the dipole antennas through via holes at the same time. Through the dipole antennas, the dual polarization antenna radiates dual polarized waves whose radiation emissions have perpendicular directions to each other. The wideband characteristics of the dual polarization antenna are improved through parasitic elements. The disclosed printed circuit board comprises: a first line hole into which a first core line (+) of a first electric cable transmitting a first electric signal is inserted; a first ground via hole through which a first ground line (−) of the first electric cable passes; a first balun hole into which a first balun cable is inserted; a second line hole into which a second core line (+) of a second electric line is inserted; is second balun hole into which a second balun cable is inserted; and a connection via-hole through which both the second core line (+) and the second balun cable pass. The first and second balun cables make a pair with the first and second electric cables respectively by being parallel to those electric cables respectively in order so perform the function of a balun. According to the invention, the dual polarization antenna is able to radiate, through the dipole antennas on both surfaces of the printed circuit boards, dual polarized waves whose radiation emissions have perpendicular directions to each other. In addition, the feeding structure can be simplified and a complex three-dimensional air-bridge structure does not need to be used in the dual polarization antenna since an electric signal is fed to the dipole antennas on both surfaces of the printed circuit board at the same time.

The invention discloses a W-waveband dual polarized slot antenna working in a TM210 resonant mode and a feed network. A radiating part and a feed part are respectively composed of a radiation chamberand a substrate integrated waveguide. Characteristics of high Q-value and low loss of a metal radiating chamber and characteristics of easy machining and easy integration are combined. A metal chamberis used as a radiator which has high radiation efficiency and improves integral efficiency of the antenna. The substrate integrated waveguide is used as a feed structure and has advantages of easy machining, relatively simple realization of a multilayer structure, and can remarkably reduce cost when compared with a metal waveguide slot feed network. The upper surface of the metal radiator is provided with four independent radiating channels, and the lower surface is provided with a resonant chamber for coupling signals of a horizontal polarized feed structure and a vertical polarized feed structure into four independent channels, thereby realizing one-to-four same-phase feeding from a single coupling slot to four radiating channels, simplifying the feed structure and reducing complexity of the feed network.

The invention discloses a broadband reconfigurable dielectric resonator antenna, which solves the problems in the prior art that the dielectric resonator antennas lack polarization reconfigurable designs and that the majority of polarization reconfigurable designs based on microstrip antennas have narrow working bandwidths and low radiation efficiency and the like. The antenna mainly comprises: adielectric substrate (1) and a dielectric resonator (2); an upper surface (101) of the dielectric substrate (1) is provided with a metal ground layer (11) and is etched with a cross seam structure (3); metallized through hole pairs (41-44) are arranged beside the cross seam structure (3); a lower surface (102) of the dielectric substrate (1) is provided with diodes (D2-D4) for controlling the on-off of the metallized through hole pairs (41-44); and the antenna is further provided with a microstrip line feed structure (13) comprising a diode (D5) and a DC bias circuit connected to the diodes (D1-D5) correspondingly. The antenna is convenient to design and is simple in structure, and due to the advantages of low cost, large bandwidth and high gain and the like, the antenna is suitable for multifunctional wireless communication applications.

The invention relates to an efficient low-profile wide-axis ratio bandwidth large-scale circularly-polarized array antenna, in particular to a circularly-polarized array antenna composed of a metal floor with a coupling gap, a thin film printed with radiation patches and sequential rotating microstrip feed networks, a main feed network and a foam or hollow dielectric plate for supporting the thinfilm. Each four sequentially and rotarily-placed corner cut radiation metal patches and one sequential rotating microstrip feed network together form a sub array, coupling with the main feed network through the gap on the metal floor is carried out, sequential 90 DEG-difference equal-amplitude excitation of each sub array element is carried out, and thus, wide-axis ratio bandwidth circularly-polarized radiation is realized. Through increasing the stage number of the power divider and the number of sub arrays of the main feed network, a large-scale circularly-polarized array antenna can be constructed. In comparison with the existing circularly-polarized array antenna technology, the efficient low-profile wide-axis ratio bandwidth large-scale circularly-polarized array antenna has the advantages of wide axis ratio bandwidth, simple structure, high radiation efficiency, low profile, light weight, low cost and easy expansion to a large-scale array, and is especially suitable for mobile terminals and satellite terminals.

The invention provides a back cavity slot antenna dual-frequency millimeter wave antenna based on a substrate integrated waveguide (SIW). The antenna comprises a radiation layer, a feed layer and a composite conversion structure, wherein the radiation layer is composed of a first metal coating and a first rectangular dielectric plate, the first metal coating is etched with two mutually parallel rectangular radiation slots, the first rectangular dielectric plate is provided with first metalized through holes for forming a circular SIW resonant cavity; the feed layer is composed of a second rectangular dielectric plate, a second upper metal coating and a second lower metal coating, the second rectangular dielectric plate is provided with second metalized through holes distributed in a gradually changing U-shaped manner so as to form a substrate integrated waveguide, and the second upper metal coating is etched with a rectangular coupling slot for slot coupling feed. The back cavity slotantenna dual-frequency millimeter wave antenna realizes the performance of millimeter wave dual-band radiation, and solves a technical problem that the dual-frequency millimeter wave antenna in the prior art is narrow in impedance bandwidth, low in antenna radiation gain and efficiency and complex in feed structure.

The invention discloses a microstrip sequential rotation array antenna based on a series and parallel feeding network. A first antenna unit, a second antenna unit, a third antenna unit and a fourth antenna unit in the array antenna are arranged on a first lambda / 4 microstrip impedance transformation line, a second lambda / 4 microstrip impedance transformation line, a third lambda / 4 microstrip impedance transformation line and a fourth lambda / 4 microstrip impedance transformation line in the series and parallel feeding network according to the serial rotation way; a feeding input end, a first feeding section, a second feeding section and a third feeding section on the series and parallel feeding network are serially arranged to form a three-quarter circular ring according to the signal input and output flow direction. The single antenna unit in the array antenna adopts the square corner cut patch design way, the processing and the forming are simple; furthermore, the single antenna unit adopts the microstrip line feeding way of allocating branches by bending, thereby being capable of leading a plurality of antenna units to conveniently constitute the array and configure at the same time of matching. When in array constituting process, the serial rotation array way and the series and parallel feeding network are adopted, thereby significantly improving the impedance bandwidth and the circular polarization purity of the antenna, reducing the loss of a feeding line and improving the gain.

The invention discloses a conical four-arm sinuous antenna, which comprises a first dielectric substrate, a second dielectric substrate and a third dielectric substrate, wherein the first dielectric substrate is a hollow truncated cone, the second dielectric substrate is arranged at the top end of the first dielectric substrate; a first group of sinuous metallic arms are arranged on the outer surface of the first dielectric substrate, and a second group of sinuous metallic arms are arranged on the inner surface of the first dielectric substrate; a first group of metallic connecting bands are arranged on the upper surface of the second dielectric substrate and a second group of metallic connecting bands are arranged on the lower surface of the second dielectric substrate; the third dielectric substrate is provided with a first group of micro-strip index gradient baluns and a second group of micro-strip index gradient baluns, wherein the first group of micro-strip index gradient baluns and the second group of micro-strip index gradient baluns are connected with the corresponding signal sources respectively; the first group of sinuous metallic arms and the first group of micro-strip index gradient baluns are electrically connected with each other through the first group of metallic connecting bands and a first group of radiating elements are formed; the second group of sinuous metallic arms and the second group of micro-strip index gradient baluns are electrically connected with each other through the second group of metallic connecting bands and a second group of radiating elements are formed.

The invention discloses a new concept broadband circularly polarized antenna. The new concept broadband circularly polarized antenna adopts the structure that a feed line is connected with an antenna radiation unit; the antenna radiation unit is etched on a dielectric baseplate; the dielectric baseplate is horizontally fixed above a reflecting plate through a supporting structure; the antenna radiation unit comprises two bending oscillators, two parasitic units, a coplanar microstrip line and a T-shaped microstrip line feed structure; the bending oscillators, the parasitic units and the coplanar microstrip line are etched on the reverse side of the dielectric baseplate; the T-shaped microstrip line feed structure is etched on the obverse side of the dielectric baseplate; the two bending oscillators are centrosymmetric about the dielectric baseplate; the coplanar microstrip line is arranged at a medial axis of the dielectric baseplate; the coplanar microstrip line comprises two wide-gap coplanar microstrip line bodies and two narrow-gap microstrip line bodies; the wide-gap coplanar microstrip line bodies feed the bending oscillators respectively to stimulate circularly polarized waves through the non-center-fed bending oscillators; besides, the broadband circularly polarized antenna adopts a novel and simple full-plane structure, and is convenient to process and form.

The invention relates to a wideband log-periodic dipole array antenna for feeding a substrate integrated waveguide. An upper metal coating (2) is provided with an upper assembly line (5), upper feed source element antennae (7), an upper surface (9) of the substrate integrated waveguide, a microstrip taper transition line (6) and a 50-ohm output microstrip line (8) which are sequentially connected, wherein the upper assembly line (5) is connected with the upper surface (9) of the substrate integrated waveguide, the upper feed source element antennae (7) are respectively arranged at both sides of the upper assembly line (5); a lower metal coating (3) comprises a lower surface assembly line (11) of the log-periodic dipole array antenna, lower surface feed source element antennae (12), a lower surface (13) of the substrate integrated waveguide and a ground surface (14) of a microstrip line; the lower surface assembly line (11) of the log-periodic dipole array antenna is symmetric in parallel to the upper assembly line (5) of the log-periodic dipole array antenna, the lower surface feed source element antennae (12) are symmetric in cross to the upper feed source element antennae (7); and the lower surface (13) of the substrate integrated waveguide is symmetric to the upper surface (9) of the substrate integrated waveguide and is connected with the ground surface (14) of the microstrip line.

The invention discloses a sixteen-unit micro-strip array antenna capable of carrying out power equal-division rotating feed. The sixteen-unit micro-strip array antenna capable of carrying out the power equal-division rotating feed is obtained in a copper coating configuration mode on a substrate, power is equally divided through a center feed network, four antenna array units are distributed, and the four antenna array units are arranged in a double-sequence mode. Due to the fact that the design mode of double-sequence rotation of feed networks is adopted by the sixteen-unit micro-strip array antenna capable of carrying out the power equal-division rotating feed, directivity of the sixteen-unit micro-strip array antenna capable of carrying out the power equal-division rotating feed can be better, the whole sixteen-unit micro-strip array antenna capable of carrying out the power equal-division rotating feed and the antenna array units have the same impedance characteristic and the same circular polarization characteristic or a better impedance characteristic and a better circular polarization characteristic, and the sixteen-unit micro-strip array antenna capable of carrying out the power equal-division rotating feed is more applicable to a satellite communication system.

The invention discloses a full-automatic double-track glue dispensing machine and a glue dispensing process thereof. The full-automatic double-track glue dispensing machine comprises a material box feeding mechanism, two conveying tracks, a glue dispensing platform and a glue dispensing assembly. The two conveying tracks are arranged in parallel in the straight line direction in a spaced mode. Thematerial box feeding mechanism is arranged at the ends of the two conveying tracks in the direction perpendicular to the conveying tracks. A material box assembly is arranged on the side portion of the front end of a transfer member. At least two material boxes are placed in the material box assembly. The glue dispensing platform is arranged in the conveying tracks. The glue dispensing assembly is arranged above the glue dispensing platform. Independent conveying of carrier boards is achieved, and the functions of clamping the boxes, distributing materials to the conveying tracks, pushing thecarrier boards to the conveying tracks and the like are simultaneously completed; frictional collision between the adjacent carrier boards is effectively avoided; and through a linear pushing mode, the positional stability of fingerprint modules on the carrier boards is ensured while the feeding and discharging efficiency is improved.

The invention discloses a conformal antenna on the holographic artificial impedance surface. The artificial impedance surface structure comprises metal patches, a dielectric layer and a metal layer; metal patches of different sizes are corresponding to different surface impedances respectively; the surface impedances are distributed based on distribution of an interference pattern of a holographic principle; the distribution of the interference pattern of the holographic principle is corresponding to a reference wave serving as a surface wave and a target wave serving as a radiation plane wave. According to the conformal antenna on the holographic artificial impedance surface, the conformal treatment is performed on the holographic artificial impedance surface and accordingly the holographic artificial impedance surface and a complex object can be conformal, a plane holographic antenna can be conformal onto the curved surface of any complex object, and accordingly any radiation can be formed.

The invention discloses an ultra-high-frequency sensor for monitoring partial discharge in a switch cabinet online. The ultra-high-frequency sensor comprises a micro-strip slot antenna and an SMA (Sub-Miniature A) connector, wherein the micro-strip slot antenna comprises a dielectric substrate, wherein a grooved metal grounding plate is arranged on one side of the dielectric substrate, and the micro-strip slot antenna is arranged on the opposite side of the dielectric substrate; the SMA connector is electrically connected with the micro-strip slot antenna. From an overall perspective, the shape of the groove in the metal grounding plate is an inverted U shape; a detail design adopts a meander technology, and the path of exciting current on the surface of the metal grounding plate is changed by bending, so that the miniaturization of an antenna is realized. In application, the ultra-high-frequency sensor is light in weight, small in size and easy to manufacture, and is beneficial to be arranged in the switch cabinet; meanwhile, the sensitivity is high; a feed structure is simple and compact; the loss of a feed line is low. Simulation and experiments prove that the return loss of the sensor in a bandwidth range is less than -10 dB; in addition, the impedance matching with a standard 50-Ohm coaxial transmission line is effectively realized by optimizing micro-strip feed line parameters and feed positions.

The invention provides a dual-polarization dielectric resonator antenna unit, and the dielectric resonator antenna unit comprises a substrate, a dielectric resonator and a director, wherein the substrate, the dielectric resonator and the director are sequentially connected from the bottom to the top. The upper surface of the substrate is provided with a grounding surface, and a gap is disposed in the grounding surface in an etching manner. The lower surface of the substrate is provided with a microstrip feed line which is matched with the gap and is used for feed. The projections of the dielectric resonator and the director on the substrate cover the gap. According to the embodiment of the invention, the dielectric resonator antenna unit meets the requirements of low profile and high gain of a dual-polarization dielectric resonator antenna unit. Moreover, a feed structure of the dielectric resonator antenna unit is symmetric, and is liable to assemble. In addition, the invention also discloses a base station antenna comprising the dielectric resonator antenna unit.

The invention discloses a broadband slot coupling multi-layer microstrip antenna based on substrate integrated waveguide feeding, which mainly solves the problems of narrow band width and poor gain stability of the existing microstrip antenna. The antenna comprises a parasitic patch (1), a first dielectric substrate (2), a main radiation patch (3), a second dielectric substrate (4), an upper floor(5), a feeding structure (6) and a lower floor (7). The parasitic patch (1) is located on the lower surface of the first dielectric substrate (2), the main radiation patch (3) is located on the uppersurface of the second dielectric substrate (4), the upper floor (5) is located on the upper surface of the feeding structure (6), and the lower floor (7) is located on the lower surface of the feeding structure (6); A longitudinal gap (51) is etch on that upper floor (5) for coupling energy from the fee structure (6); An air layer is arranged between the parasitic patch (1) and the main radiationpatch (3) for widening the antenna bandwidth. The invention improves working bandwidth and gain stability, and can be applied to 5G communication and radar system.

Provided are a conductive structure for a high gain antenna and an antenna. A plurality of conductive patterns (512) of the conductive structure are formed on top and bottom surfaces of a dielectric substrate (511) positioned above the antenna and separated from an antenna body (500). A conductive upper structure of the antenna (510) is positioned above the antenna opposite to a ground plane (530) to which the antenna body is fed, separated from the antenna body. A conductive unit structure comprising a plurality of conductive patterns (512) formed on top and bottom surfaces of the dielectric substrate (511) is arranged in a plurality of layers. The conductive structure for a high gain antenna and the antenna can be readily produced by using low cost printed circuit board (PCB) technology, and a gain of the antenna can be increased regardless of a resonance distance between the ground plane of the antenna and the conductive structure disposed above the antenna.

The invention relates to a UHF RFID card reader antenna. The antenna comprises radiation unit layers with radiation patches, parasitic patch layers with parasitic patches, feed structural layers withfeed strips and metal floors; the parasitic patch layers are oppositely arranged on one sides, towards the radiation patches, of the radiation unit layers at intervals; the feed structural layers areoppositely arranged on one sides, back to the parasitic patch layers, of the radiation unit layers at intervals; the metal floors are oppositely arranged on one sides, back to the radiation unit layers, of the feed structural layers at intervals; in addition, the two ends of the feed strips are electrically connected with the metal floors and the radiation patches; and the feed strips adopt a shape of an Archimedean helical curve, and a width gradually-changed structure. The UHF RFID card reader antenna is simple in feed structure, so that the overall antenna structure is simple in structure.The invention also relates to a UHF RFID card reader system which comprises the UHF RFID card reader antenna. Therefore, the UHF RFID card reader system can be applicable to the use frequency band ofthe world-wide UHF RFID, and simplification and miniaturization of the overall system structure can be realized.

The invention discloses a directional diagram reconfigurable planar array antenna based on digital coding representation and a control method thereof. The array antenna comprises a coaxial connector,a dielectric substrate, a metal ground located on the lower surface of the dielectric substrate and a metal pattern located on the upper surface of the dielectric substrate. The metal pattern comprises a coding unit patch, a series-parallel hybrid feed network patch and a two-way power divider patch. The series-parallel hybrid feed network patch comprises a first main feed line and a second main feed line which are connected in parallel. Wherein the first main feeder line and the second main feeder line are axially divided into four series feeder lines, each series feeder line is symmetricallydistributed on two sides of the first main feeder line or the second main feeder line, two ends of each series feeder line are respectively connected with a coding unit patch, and the first main feeder line and the second main feeder line are connected with the coaxial connector through a two-way power divider patch. The antenna has the advantages of low profile, light weight, high gain, real-time switching of radiation wave beams and shapes and the like, and has a wide application prospect.

The invention provides a wideband circular polarization high gain combined antenna. The combined antenna comprises a micro-strip antenna and a pyramid horn antenna, wherein the micro-strip antenna comprises an upper layer dielectric substrate, a lower layer dielectric substrate and support foam, wherein a circular structure is sculptured on the center of the upper surface of the lower layer dielectric substrate, two symmetrical cutting angles along a circle diameter direction are arranged on the external circle of the circular structure, four central symmetry circle radiation pasting slices with equal sizes are evenly sculptured on the lower surface of the upper layer dielectric substrate, the lower surface of the upper layer dielectric substrate is installed on the upper surface of the lower layer dielectric substrate through the rigid support foam, centers of the circle radiation pasting slices with cutting angles are aligned with the symmetric center of the circle radiation pasting slices, the pyramid horn antenna is in a taper frame structure, and an open end of the pyramid horn antenna, with a small opening diameter, is installed on the upper surface of the lower layer dielectric substrate, and furthermore the upper layer dielectric substrate is surrounded inside the pyramid horn antenna. The wideband circular polarization high gain combined antenna can simultaneously guarantee good impedance, circular polarization and high gain radiation properties in a wide frequency band.

The invention discloses a high-order mode single-pulse antenna based on substrate integrated waveguide. A feed network, an upper layer medium base plate and a substrate integrated waveguide cavity aresequentially arranged from top to bottom. The feed network comprises a difference port network and a port network respectively arranged at two ends of an antenna; the substrate integrated waveguide cavity is divided into four independent symmetrical sub waveguide cavities through a first metal through hole in a shape like a Chinese character 'tian'; the difference port network and the port network respectively correspond to two sub waveguide cavities and respectively correspond to one row of second metal through holes; 180-degree phase differences are formed in the sub waveguide cavity corresponding to the difference port network, so that difference beams are obtained; and sum beams are obtained in the sub waveguide cavity corresponding to the port network. The single-pulse antenna provided by the invention has the advantages of simple structure, high radiation efficiency and low profile. The feed network design of the single-pulse antenna is greatly simplified.

The invention discloses a highly integrated four-channel S-band transceiver module, comprising a receiving channel, a transmitting channel and an external interface, wherein the receiving channel comprises paired band branch I and Q receiving channels, and the transmitting channel comprises paired band branch I and Q transmitting channels. The two-port feeding of the transceiver module can effectively improve the circular polarization axis ratio of the antenna, and the transceiver channels are separated, which can improve the isolation of the transceiver, reduce the interference between channels and help to improve the communication capability of the system. Furthermore, the invention also discloses a phased array antenna with the high-integration four-channel S-frequency transceiver module, which can realize polarization adjustability by cooperating with a four-point feeding antenna unit, realizes polarization conversion and beam scanning of the phased array antenna through electroniccontrol phase shift and branch switching, effectively reduces the antenna port surface, and realizes miniaturization design.

The invention belongs to the field of microwave energy utilizing devices, and provides a continuous transmission type focusing microwave reactor. The continuous transmission type focusing microwave reactor comprises a reaction device, a transmission device, a feed device and a supporting device, and is characterized in that the feed device comprises a metal reflecting surface, a radiating trumpet, a coaxial transmission line, a waveguide coaxial converter and a microwave source, wherein the metal reflecting surface is arranged on the inner wall of the top surface of a metal cavity; the microwave source is connected with the radiating trumpet through the coaxial transmission line and the waveguide coaxial converter; the radiating trumpet is fixed to the side wall of the metal cavity, runs through the metal cavity, and irradiates at a certain inclination angle relative to the wall of the metal cavity, so that the focus of the metal reflecting surface is positioned in the direction of a main lobe of the radiating trumpet. In a way of irradiating a detected object at a maximum field strength point by feeding the side end of a waveguide into the metal wall, reflecting and focusing, the continuous transmission type focusing microwave reactor improves the reaction efficiency, speeds up the reaction, improves the reaction uniformity and saves the energy; the continuous transmission type focusing microwave reactor is combined with a continuous transmission type production line, and is applied to large-scale industrial production.

The invention discloses a low-sidelobe scanning method of a low-cost four-dimensional transmission array antenna. The innovation point of the invention is that a four-dimensional antenna theory is combined with a PIN diode controlled 2-bit reconfigurable transmission array antenna technology, and a transmission array unit with 2-bit phase shift is used to replace a large number of T / R assemblies,so that a complex and heavy feed structure is avoided, and the manufacturing cost is effectively reduced; by introducing a periodic time modulation function to each transmission array unit, the amplitude and phase range of each unit is expanded, so that the low sidelobe scanning characteristic is realized; the low sidelobe scanning directional diagram synthesis, namely the time sequence design process of a time modulation function, is completed in two stages: firstly, according to a convex optimization comprehensive center frequency directional diagram, reducing four phase conduction durationsinto a variable by utilizing a certain constraint condition; and then utilizing the differential evolution algorithm to suppress the sideband level. The method can be used in wireless communication and radar systems.

The invention discloses a cloth pulling and feeding mode of a cutting machine and a cloth pulling and feeding device of the cutting machine. According to the cloth pulling and feeding device, a firstpressing component and a second pressing component are arranged at the two ends of a rack correspondingly, a driving component is arranged on the side surface of the rack, a sliding rail is arranged on the rack, a sliding component is arranged on the sliding rail, the sliding component and a cloth pulling component are mutually fixed, the cloth pulling component is positioned between the first pressing component and the second pressing component, the driving component is in transmission connection with the sliding component, a tensioning roller is further arranged on the rack, the tensioning roller is used for tensioning the annular conveying belt, the annular conveying belt is positioned below the first pressing component, the cloth pulling component and the second pressing component, theannular conveying belt is made of a material capable of being magnetically attracted, an electromagnet is arranged at the bottom of the cloth pulling component, the first pressing component, the second pressing component, the driving component, the cloth pulling component and the electromagnet are electrically connected with a controller. The cutting machine has the advantages that the amount ofthe cloth distributed at one time is large and the cloth is not easy to deviate; moreover, the feeding structure is simple, the assembling is convenient, and the maintenance is convenient.

The invention provides a double ellipse helical antenna, comprising a main ellipse helical coil, a medium basal plate, a matching circuit and a coaxial SMA adaptor, wherein, the double ellipse helical antenna also comprises a parasitical ellipse helical coil which is in coupling connection with the main ellipse helical coil. The double ellipse helical antenna has the advantages of relatively high gain, simple feeding structure and small volume, and is particularly applied to the hand-held mobile communication equipment.

The invention discloses a three-frequency polarization reconfigurable single-feed patch antenna which comprises a first dielectric substrate, a second dielectric substrate, an input port, PIN diodes,inductors, capacitors and voltage modules. The first dielectric substrate is located above the second dielectric substrate, and an air layer is formed between the two dielectric substrates. A rectangular radiation patch is arranged on the top surface of the first dielectric substrate. Open-circuit stub lines are loaded on three sides of the rectangular radiation patch, and the open-circuit stub lines are connected with the rectangular radiation patch through the PIN diodes. Three slots parallel to the adjacent sides are formed in the rectangular radiation patch, and one PIN diode is connectedto the center of each slot in a bridging manner. A floor with a slot is arranged on the top surface of the second dielectric substrate, a micro-strip feeder line of the input port is arranged on the bottom surface, and the micro-strip feeder line of the input port excites the rectangular radiation patch through the slot in the floor. According to the invention, polarization characteristic switching can be realized in three frequency bands, and the antenna has the advantages of flexible design, low profile, low axial ratio, low cost and the like.

The invention relates to the field of cavity-backed antennas, and discloses a quasi-coaxial crack feed cavity-backed antenna which comprises a step structure type symmetrical oscillator, an impedance transformer, a dielectric radome, a quasi-coaxial crack balancer, a foam layer and a circular reflection cavity. The dielectric radome is assembled on the circular reflection cavity, the symmetrical oscillator is assembled on the quasi-coaxial crack balancer, and the foam layer is arranged between the stepped structure type symmetrical oscillator and the dielectric radome and is used for fixing the relative distance between the symmetrical oscillator and the dielectric radome. According to the cavity-backed antenna provided by the invention, a quasi-coaxial crack balanced feed structure is adopted, the advantages of the traditional coaxial crack balanced feed and the double-line balanced feed are combined, and the impedance conversion and the coaxial crack structure are integrated, so that the purposes of eliminating the directional diagram distortion existing in a current popular broadband cavity-backed antenna form, improving the structural reliability and the power capacity under the high-strength condition and enabling the frequency band width to be not smaller than 3: 1 are achieved.