44results about How to "Improve axle ratio" patented technology

A circularly-polarized-wave patch antenna includes a main body having a patch electrode provided with two feeding points and a circuit for generating a phase difference of 90° between signals supplied to the feeding points. A Wilkinson distribution circuit is provided between the 90°-phase-difference generating circuit and a coaxial cable (feeder line) so as to improve a reflection characteristic. The patch antenna includes two feeding points, and thus a favorable axial ratio characteristic can be obtained in a wide band. Also, a favorable reflection characteristic can be obtained in a wide band because of the Wilkinson distribution circuit. Accordingly, the patch antenna can be used in a wider frequency band.

A tri-band satellite navigation antenna for a COMPASS, a GPS and a GLONASS comprises three layers of micro-strip antenna bodies, feed coaxial probes, metal clamp plates, strip line mediums, feed networks and a set of metal screws. High-dielectric-constant ceramic mediums are adopted in all the mediums of the three layers of micro-strip antenna bodies so as to reduce the size of the antenna. Circular polarization of the first-layer micro-strip antenna body is realized through the methods of single-point feed and angle cutting on a metal patch, and circular polarization of the second-layer micro-strip antenna body and circular polarization of the third-layer micro-strip antenna body are realized through double-point feed. The number of the feed probes contained in the medium of each layer of micro-strip antenna body is not more than two, so that three ports have better electromagnetic isolation. The set of metal screws is arranged around the micro-strip antenna bodies, the metal screws can be used for fixing the metal clamping plates and strip line feed layers, and the metal screws can also expand the lobe width of the antenna. The tri-band three-port antenna has the advantages of being small in size, low in section, wide in lobe, good in low elevation angle gain and axial ratio and high in port insulation degree, and suiting to be used as a satellite navigation terminal receiving antenna.

A polarization switching/variable directivity antenna according to the present invention includes a radiation conductor plate 12 on a front face, and a ground conductor plate 14 on a rear face, of a dielectric substrate 11. At least one directivity switching element and at least two polarization switching elements are provided within the ground conductor plate 14 on the rear face. The directivity switching element includes a first slot which is formed by a removing a loop-like portion from the ground conductor plate 14 and at least two directivity switching switches (22a to 22d). Each polarization switching element includes a first slot which is formed by removing a loop-like portion from the ground conductor plate 14 and at least one polarization switching switch (23a to 23d). Switching of a maximum gain direction of radiation directivity of the antenna is realized through control of the directivity switching switches 22a to 22d, and switching of the rotation direction of a circularly polarized wave which is emitted from the antenna is realized through control of the polarization switching switches 23a to 23d.

The invention discloses a circularly-polarized cross dipole GPS navigation antenna. The antenna comprises an upper dielectric substrate, a lower dielectric substrate, an intermediate dielectric substrate, a radiation unit, a parasitic unit and a feed unit, wherein the upper dielectric substrate and the lower dielectric substrate are arranged in parallel; the intermediate dielectric substrate is arranged between the upper dielectric substrate and the lower dielectric substrate and is perpendicular to the upper dielectric substrate and the lower dielectric substrate; and a reflecting plate is arranged on the lower surface of the lower dielectric substrate. The antenna is small in size, is large in bandwidth, is wide in beam, and can be well applied to GPS satellite navigation terminal devices.

A polarization switching/variable directivity antenna according to the present invention includes a ground conductor plate 12 on a surface of a dielectric substrate 11, and has a radiation element 13, a directivity switching element 15, and polarization switching elements 16 provided on the ground conductor plate 12 side of the dielectric substrate 11. The radiation element 13 includes a first slot 17a formed by removing a loop-like portion from the ground conductor plate 12. The directivity switching element 15 includes a second slot 17b formed by removing a loop-like portion from the ground conductor plate 12 and directivity switching switches 18. The polarization switching elements 16 includes a third slot 17c formed by removing a linear-shaped portion from the ground conductor plate 12 and polarization switching switches 19a to 19d. Through control of the directivity switching switches 18, switching of a maximum gain direction of radiation directivity of the antenna is realized. Through control of the polarization switching switches 19a to 19d, switching of a rotation direction of a circularly polarized wave which is emitted from the antenna can be realized.

The invention discloses a dual-frequency three-polarization MIMO antenna and a wireless communication device, the antenna includes a dielectric substrate, a floor, three feeder wires and two radiationpatches, the floor is arranged on the upper surface of the dielectric substrate, and a dumbbell-shaped gap is etched on the floor, the dumbbell-shaped gap has a long slit and two grooves connected toboth ends of the long slit, The three feeder lines and two radiation patches are arranged on the lower surface of the dielectric substrate, wherein one feeder line corresponds to the long slit of thedumbbell-shaped slot, and the other two feeder lines, two radiation patches and two grooves of the dumbbell-shaped slot are in one-to-one correspondence, each radiation patch is connected with a corresponding feeder line; The wireless communication device includes an antenna as described above. The antenna of the invention has dual-frequency and three polarization characteristics, and is easy toprocess, simple in structure, low in cost and wide in frequency bandwidth. The linear polarization can be applied to Bluetooth of 1.98 GHz to 2.9 GHz, Wi-MAX, ISM and other communication frequency bands, and circular polarization can be applied to the Wi-MAX of 3.13 GHz to 4.53 GHz, 5G and other communication bands.

The invention brings forward an anti-interference microstrip array antenna, and is especially applied to a Beidou third-generation satellite navigation system. The anti-interference microstrip array antenna employs elliptical microstrip antenna array elements so as to enable mutual coupling between the array elements to be quite low and effectively improve the anti-interference capability of the array antenna. Compared to a conventional rectangular microstrip array antenna, the bandwidth of the anti-interference microstrip array antenna is improved by more than one time, and the requirement of a Beidou third-generation BOC modulation mode can be completely satisfied. The anti-interference microstrip array antenna comprises the N microstrip antenna array elements, a medium substrate and a metal reflection base plate, wherein the microstrip antenna array elements are arranged at the upper surface of the medium substrate according to certain intervals, and the metal reflection base plate is arranged at the lower surface of the medium substrate; and the microstrip antenna array elements are elliptically-shaped for radiating circular polarized waves, and the microstrip antenna array elements are provided with a coaxial feed point for feeding into electromagnetic wave signals.

The invention provides a satellite navigation antenna which comprises a first printed symmetrical dipole circuit board and a second printed symmetrical dipole circuit board. Two printed symmetrical dipole circuit boards are orthogonally arranged on a grounding plane printed circuit board to form an orthogonal polarization antenna. The bottom layer of each printed symmetrical dipole circuit boardsis a downdip symmetrical dipole, and the top layer is a microstrip balun. The top layer of the grounding plane printed circuit board is a grounding plane, and the bottom layer is provided with an antenna feed network. The satellite navigation antenna uses the printed symmetrical dipoles as antenna radiation units, and has the advantages of light weight and low cost.

The invention provides a vehicle-mounted built-in dual-band dual-circularly-polarized mixed dielectric resonator antenna. The antenna comprises a dielectric resonator, a dielectric substrate, a metal ground plane and a microstrip line, the microstrip line is arranged in the center of the bottom of the dielectric substrate, the metal ground plane is arranged on the surface of the dielectric substrate, and a gap is formed in the center of the metal ground plane and is perpendicular to the bottom microstrip line. The dielectric resonator is arranged right above the gap; the dielectric resonator comprises a prismoid, a mixing cylinder is arranged on the upper portion of the prismoid, the mixing cylinder is a hollow cylinder, liquid is arranged in the hollow cylinder, and the cylinder of the hollow cylinder is a metal dielectric medium. Triangular prism-shaped notches are formed in opposite angles of the upper part and the lower part of the prismoid; double frequency bands are obtained through slot coupling feeding, a basic mode and a high-order mode, the hybrid antenna is realized by adding liquid into a hollow hollow cylindrical part, the high-frequency bandwidth is expanded, the low frequency is hardly influenced, the gain of the antenna is improved after water is added, and the gain is increased when the water is increased at high frequency.

The invention discloses a wide-beam frequency-reconfigurable printed four-arm spiral navigation antenna which comprises an independent lower spiral body, an independent upper spiral body and an independent parasitic oscillator. The upper spiral body comprises a second dielectric sheet, a second spiral arm printed on the second dielectric sheet, a second short circuit connecting arm printed on the second dielectric sheet and a second mechanical structure for supporting the second dielectric sheet; the lower spiral body comprises a first dielectric sheet, a first spiral arm printed on the first dielectric sheet, a first mechanical structure supporting the first dielectric sheet and a feed probe arranged on the bottom floor. The bottom floor is provided with four probes for feeding, feeding is carried out through the four probes at the bottom, and the circular polarization characteristic of the antenna is achieved by endowing four signals which are equal in amplitude and have the phase difference of 90 degrees in sequence. According to the invention, a single structure covers a global navigation frequency band and broadens a directional diagram wave beam, the gain at a low elevation angle is improved, the anti-interference capability is enhanced, and the antenna has the characteristic of miniaturization when being used as a single-frequency-band antenna.