109results about How to "Good omnidirectional" patented technology

An antenna structure for receiving digital television broadcast signals includes a vase antenna housing having a generally hourglass shape with conically-shaped upper and lower segments joined together to define a narrower diameter middle portion. The antenna structure further includes a signal receiving antenna etched on the inner surface of the vase antenna housing. The signal receiving antenna conforms to the shape of the vase antenna housing and thereby exhibits an arcuate, partial hourglass shape. The signal receiving antenna may be a cloverleaf antenna or a spiral antenna.

The invention relates to a data transmission system for an underwater acoustic network, which comprises a plurality of independent underwater nodes, wherein each underwater node is equivalently connected with at least the other underwater node. The data transmission system also comprises a transmitting optical antenna, a receiving optical antenna, a light source, an optical modulator, an optical receiver, an underwater acoustic transducer/receiving transducer, a digital signal processor and a positioning module, wherein the positioning module is provided with a rotating device and used for completing the alignment between the light source and the optical receiver; the transmitting optical antenna, the light source, the optical modulator and the digital signal processor are in signal connection with each other in turn; the receiving optical antenna, the optical receiver and the digital signal processor are in signal connection with each other in turn; the digital signal processor is also in signal connection with the positioning module and the underwater acoustic transducer/receiving transducer respectively; and the light source is a blue-green laser source. The invention also relates to a data transmission method for the underwater acoustic network. The invention reduces the collision probability of data in the transmission process, improves the success rate of the construction of a communication link, saves the network bandwidth, and improves the network throughout.

Durable hydrophobic antireflection structures for optical elements, optical windows, and front sheets of encapsulated photovoltaic and photonic devices are disclosed which can minimize reflection losses over the entire accessible portion of the solar spectrum simultaneously provide self-cleaning and finger-print-free surface. Reduced reflectance and self-cleaning surfaces are resulted from coating the front sheet of encapsulated device with combination of nonporous and porous nanostructured materials such as silicon dioxide nanorods and PTFE. Step-graded antireflection structures can exhibit excellent omnidirectional performance, significantly outperforming conventional quarter wavelength and low-high-low refractive index coatings. Methods of constructing nanostructured durable optical coatings with hydrophobic surfaces are disclosed that can cover large-area ridged and flexible substrates.

The invention is applicable to the technical field of wireless communication devices and discloses a dual-band omnidirectional WIFI (wireless fidelity) antenna. The dual-band omnidirectional WIFI antenna comprises a dielectric plate and two pairs of dual-band radiating elements, the dual-band radiating elements are connected to the dielectric plate, a balance microstrip line is connected between the two dual-band radiating elements, each dual-band radiating element comprises two low-frequency radiating arms and two high-frequency radiating arms, and the low-frequency radiating arms and the high-frequency radiating arms are symmetrically arranged on two sides of the balance microstrip line. The dual-band omnidirectional WIFI antenna is wide in a covered range and high in gain.

The present invention provides a miniature wideband antenna for 5G, which includes a dielectric substrate, a coplanar waveguide feed structure on a front of the dielectric substrate, a main radiator, a second and third radiators and a first radiator on a back of the dielectric substrate. The antenna is small in size with operation band of 3 GHz-30 GHz which covers the various 5G frequency band and covers the current wireless modes of Wi-MAX, W-LAN, UWB and so on. The antenna guarantees future compatibility for various complicated communication modes and has good perspectives for many applications. Based on the antenna, the double-unit and four-unit MIMO antenna adopts orthogonal polarization and metamaterial unit. Thus, high unit separation is achieved without increase on the size of the antenna unit. The present invention has wide applications in small mobile device such as cell phone and laptop.

The invention provides a mini enhanced dual-polarization omnidirectional ceiling antenna. The antenna comprises a single cone, a horizontal polarization unit and a step-shaped floor which are arranged in a vertically coaxial and centrally overlapped manner from top to bottom successively, the single cone comprises a first single cone radiator and a second single cone radiator which are arranged in a crossing manner, the bottom of the single cone is provided with a feed point, and a coaxial feed cable is connected to the feed point in the bottom of the single cone by penetrating the step-shaped floor and the horizontal polarization unit from bottom to top successively. Within the frequency range from 0.8GHz to 2.70GHz, the single-cone ceiling antenna realizes effective impedance match, an ideal omnidirectional radiation performance, a substantial edge coverage enhanced effect, a consistent in-band coverage range, higher efficiency, higher port isolation degree (better than -24dB), small size and low profile and is suitable for indoor coverage. The antenna is also characterized by being novel in ideas, clear in principles, universal in methods, easy to realize, low in cost and suitable for batch production, the antenna can be used to replace a routine dual-polarization omnidirectional ceiling antenna, and can be used for design and improvement of a vertical-polarization enhanced omnidirectional ceiling antenna and a planar Alford loop antenna.

The invention provides an omnidirectional dual circularly polarized antenna which is an integrally coaxial structure; a medium is filled between inner and outer conductors which are coaxially arranged; rectangular gaps (with an included angle of 90 degrees) which are perpendicular with one another are formed in the conductor wall of the outer conductor of an antenna radiation structure; the upper and the lower gaps which are perpendicular with one another are divided into a group to form a gap pair; four groups of gaps are formed in the periphery of the conductor wall to form a radiation unit; the four groups of the radiation units are arranged up and down to form a radiation array which is an antenna radiation section. Upper and lower ends of the antenna radiation structure are respectively used as dual circularly polarized two feeder ports; a coaxial tapered transmission line structure is adopted for changing the interface into a practical SMA interface dimension for performing radio frequency feeder. According to the embodiment disclosed by the invention, the omnidirectional performances and the dual circularly polarized performances are good, the working frequency band is 5.1-5.9GHZ, -15dB isolation bandwidth is 12.8%, a reflection coefficient in the isolation bandwidth is smaller than (-)10dB, omnidirectional surface gain within the band is 3dBic-dBic, and the omnidirectional average axial ratio is smaller than 3dB.

The invention discloses a low-frequency ultra-wideband planar omnidirectional antenna. The antenna includes a dielectric substrate, a metal radiation patch, a metal ground plate and a loading resistor. The dielectric substrate is made from FR-4, and has a first surface and a second surface opposite to the first surface. The metal radiation patch is arranged on the first surface of the dielectric substrate. The metal ground plate and the loading resistor are arranged on the second surface of the dielectric substrate. The metal radiation patch is formed by a U-shaped patch and a disc. The tail end of the U-shaped patch and the top end of a gradual changing microstrip feed line are connected via an inverted triangular metal patch. The metal ground plate is a rectangular frame metal patch, a trapezoid patch and two long strip patches are arranged inside the metal rectangular frame, and the same load resistance is applied to the two ends of the metal rectangular frame. Feeding of the whole antenna is carried out through a 50[omega] coaxial line. The low-frequency ultra-wideband planar omnidirectional antenna provided by the invention is compact in structure and wide in bandwidth scope, and exhibits good low frequency omnidirectional performance.

The invention provides an omnidirectional dual circularly polarized antenna with same-side feeding. The antenna comprises a radiation structure, a similar coaxial impedance matching structure, and a radio frequency excitation conversion T-shaped connecting structure, the similar coaxial impedance matching structure is divided into an upper similar coaxial impedance matching structure and a lower similar coaxial impedance matching structure, the upper end and the lower end of the radiation structure are respectively connected with the lower end of the upper similar coaxial impedance matching structure and the upper end of the lower similar coaxial impedance matching structure, the upper end of the upper similar coaxial impedance matching structure is sealed by a metal disc plate, the lower end of the lower similar coaxial impedance matching structure is connected with the radio frequency excitation conversion T-shaped connecting structure, and an interface of the radio frequency excitation conversion T-shaped connecting structure can directly perform radio frequency excitation by employing an SMA joint feed line. According to the antenna, the omnidirectional performance and the axial ratio performance are good, a certain working bandwidth of -10dB bandwidth 600M (5.2GHz-5.8GHz) is achieved, and in-band gain is greater than 5.2dB and can reach 6.7dB to the maximum.

The present invention relates to a multi-rotor unmanned aerial vehicle high-gain omnidirectional conformal diversity antenna technology, and relates to a high-gain unmanned aerial vehicle conformal antenna. By organizing an array on the basis of the radiation arrays of the common PCB dipole forms and carrying out the fine phase feed, the series feed antennas and the parallel feed antennas of the radiation arrays are conformal successfully, have the high gain, and are easy to be conformal with an undercarriage of an unmanned aerial vehicle, thereby realizing the horizontal and vertical polarization. By the diversity of the two kinds of antennas, the conditions of an end-emission type antenna array and an edge-emission type antenna array are satisfied. The multi-rotor unmanned aerial vehicle high-gain omnidirectional conformal diversity antenna technology is especially suitable for being applied to the MIMO and OFDM wireless communication systems, and the working frequency bands can be WIFI 2.4 GHz or 5.8 GHz and ISM 433 MHz, 1.2 GHz and 900 MHz, also can be the legal frequency bands used for an unmanned aircraft system of 840.5-845 MHz and 1430-1440 MHz.

The invention discloses an MIMO multiantenna communication system. The system comprises a transmitting end and a receiving end. The transmitting end and the receiving end are equipped with uniform spherical MIMO antenna arrays. The invention also provide a performance evaluation method for the MIMO multiantenna communication system. The provided system is described through scatterer Gaussian distribution. A spatial Gaussian distribution density function expression is determined. A joint probability density function of an angle of divergence (AOD) of a single-time bounce SBM component is expressed. An edge PDF of the angle of divergence (AOD) of a single-time bounce path SBM in the system is provided through utilization of integral of the joint PDF on a path length interval component. Fourier transform is carried out on pulse response h<pq>(t) to obtain a time varying transfer function. A frequency cross-correlation function is expressed. According to the system and the method, throughimporting of the spatial autocorrelation function, and temporal and frequency cross-correlation functions between two array elements pq, performance of the MIMO multiantenna communication system is evaluated, and the performance of terminal antenna arrays and a wireless communication system is optimized.

The present invention provides a circularly polarized antenna-based space diversity coverage receiving and transmitting system. The system comprises a lower radiating body and an upper radiating body; the lower radiating body covers the whole horizontal direction; the upper radiating body covers an upper half part; and the lower radiating body and the upper radiating body can be disassembled from each other, so that the upper radiation antenna can be replaced according to needs. According to the system of the invention, the lower radiating body antenna has high efficiency and high gain; the lower radiating body antenna has good omnidirectional performance and wide bandwidth; and the upper radiating body antenna can be flexibly designed according to actual needs, so that actual communication needs can be satisfied.

The invention discloses an omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer, wherein the transducer comprises a cylindrical neodymium-iron-boron magnet, a magnetic concentrator and a circular array type back-folding line ring. The multi-cluster circular zigzag line ring in a flexible circuit board is placed on the surface of an aluminum plate to be detected,and the magnetic concentrator and the neodymium-iron-boron magnet are attracted and then placed right above a return line ring. Based on lorentz force effect, the stimulating of omni-directional S0 modal guided wave in a plate structure is realized. Experiments verify that the prepared array type omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer can be usedfor stimulating a single S0 mode guided wave in the aluminum plate; with an omni-directional test experiment carried out, the developed omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer can stimulate to a S0 guide wave spread in the 360-degree direction; and a defect detection experiment verifies that the omnidirectional magnetic concentrator type lamb wave electromagnetic acoustic transducer can effectively reduce the analysis difficulties and errors of defect signals.

The invention discloses an omnidirectional-radiation broadband circular polarization antenna, which belongs to the technical field of wireless communication equipment. The circular polarization antenna comprises an omnidirectional antenna and a hollow cylindrical circular polarizer located outside the omnidirectional antenna, wherein the axes of the omnidirectional antenna and the hollow cylindrical circular polarizer are coincident and the distance is 0.2 lambda0 to 0.4 lambda0; the hollow cylindrical circular polarizer comprises n layers of coaxial broken line-type metal polarization gratings, each broken line-type metal polarization grating layer is formed by parallelly-arranged broken line gratings covering the side surface of a hollow dielectric cylinder, broken line grating units arerepeated periodically to form each broken line grating, the line width of the broken line grating unit is 4*10<-3> lambda0 to 0.03 lambda0, the height is 0.1 lambda0 to 0.3 lambda0, the width of a U-type part is 0.025 lambda0 to 0.1 lambda0, the gap between adjacent broken line gratings is 0.1 lambda0 to 0.5 lambda0, and the included angle between the axis of the broken line grating unit and theaxis of the hollow cylindrical circular polarizer is 45 DEG. According to the broadband circular polarization antenna provided in the invention, an antenna radiating circular polarization electromagnetic waves can be obtained in a polarization torsion mode, and the antenna is good in omnidirectional performance, low in a circular polarization axial ratio, wide in frequency band and high in gains.

The invention relates to the technical field of antennas, and particularly relates to a miniaturized ultra-wideband microstrip antenna. The antenna comprises a substrate, and a radiation patch and a grounding part are arranged on the substrate; the radiation patch comprises a monopole and a coupling structure; the coupling structure comprises a first part and a second part; the first part and thesecond part are arranged on two sides of the substrate; the first part comprises a second sub-patch, two parallel first sub-patches and two parallel third sub-patches, and the two first sub-patches and the two parallel third sub-patches are arranged on the two sides of the second sub-patch respectively; and the second part is a U-shaped structure. A size of the ultra-wideband microstrip antenna isonly 20mm*34mm, the ultra-wideband microstrip antenna has the small size, and the ultra-wideband microstrip antenna also has advantages of an ultra-wideband, a high gain and good omnidirectivity under the condition that the size is reduced. According to the antenna, an effective working frequency band is 3.05-11.08GHz, a total bandwidth is 8GHz, an average gain is higher than 5dBi, a peak value is 8.2dBi, and an omnidirectional radiation characteristic is achieved at 3.1-6GHz.

The invention discloses a loudspeaker and a loudspeaker system. First sound circulation passageways and second sound circulation passageways are respectively arranged on the two sides of an irradiator. The first sound circulation passageways extend to the edge of the irradiator from the position of the radiator that is directly facing a first sound producing unit through gradually getting away from the first sound producing unit in the X-axis direction. The second sound circulation passageways extend to the edge of the irradiator from the position of the radiator that is directly facing a second sound producing unit through gradually getting away from the second sound producing unit in the X-axis direction. According to the technical scheme of the loudspeaker, sound waves emitted from the first sound producing unit are radiated to the outside through a plurality of first sound circulation passageways on the radiator. Meanwhile, sound waves emitted from the second sound producing unit are radiated to the outside through a plurality of second sound circulation passageways on the radiator. Therefore, the 360-degree diffusion of the sound fields of the two sound producing units can be realized. Meanwhile, the omni-directional property of the sound field of a tweeter unit is improved, so that the loudspeaker can be made smaller. Moreover, the stereophonic effect of the loudspeaker can be simultaneously ensured.

The invention provides a combined type UHF frequency range CB antenna comprising a pedestal, a short antenna, and a long antenna; the pedestal is connected with the short antenna; the long antenna is detachably connected with the short antenna; the short antenna and the long antenna respectively comprise an antenna housing made of taper glass fibers; the antenna housing uses the taper glass fiber to reduce the wind resistance and antenna weight, thus ensuring the antenna usage intensity, and providing more beautiful appearance; the short antenna and the long antenna are threaded by a connector, and different connectors can be replaced so as to match with long antennas of different calibers; in addition, a screw is added for fixation enhancement, thus ensuring the long antenna not to loosen in vehicle-mounted usage; the short antenna and long antenna are installed in a separated mode; the antenna only needs to be mounted once, and can be freely switched to high or low gain antennas, thus complying with different usage conditions, and saving cost.

The invention discloses a loudspeaker. The loudspeaker comprises a radiator and a sounding unit which is fixed to one side of the radiator, wherein one side, which is close to the sounding unit, of the radiator is provided with a plurality of concave first sound circulation channels through which sound waves of the sounding unit flow; and the first sound circulation channels extend from a position, which is opposite to the sounding unit, on the radiator to an edge of the radiator in a way of gradually getting far away from the sounding unit along an X-axis direction. According to the loudspeaker, sound waves emitted by the sounding unit are radiated out through the plurality of first sound circulation channels on the radiator, so that 360-degree diffusion of a sound field of the sounding unit is realized; a sound field of a high-pitch unit is improved to be omni-directional; and the loudspeaker can be made smaller. Moreover, through adoption of the loudspeaker, sound can be circulated better in the sound circulation channels, and the problem of emission or diffraction is solved, so that other noise is not introduced in the finally-radiated sound.

The invention provides a smart TV antenna and a smart TV. The smart TV antenna is disposed in the TV, the smart TV antenna comprises: a printed circuit board, wherein the printed circuit board comprises a first surface and a second surface, which are opposite to each other; a grounding metal layer, wherein the grounding metal layer is disposed on the first surface; at least two radiation regions,wherein the at least two radiation regions are disposed on the second surface; and a metal loading layer, wherein the metal loading layer is disposed on the second surface and is located between the radiation regions, the metal loading layer is electrically connected with the grounding metal layer through a through hole passing through the printed circuit board, and the radiation regions are electrically connected with the metal loading layer to enhance the vertical polarization characteristics of the radiation regions. The smart TV antenna provided by the invention enhances the vertical polarization characteristic, which is beneficial to improving the data transmission throughput rate and the omnidirectionality, and reducing the dead zones of wireless signals of the TV.

The invention discloses a single-chip rectangular omnidirectional antenna. The single-chip rectangular omnidirectional antenna comprises a rectangular substrate, a U-shaped metal grounding sheet, multiple rectangular radiation sheets, a bending line metal radiation structure and a groove structure. The single-chip rectangular omnidirectional antenna aims at solving the problems that conventional omnidirectional antennas are low in gain, expensive in plate material and poor in omnidirectional performance. The single-chip rectangular omnidirectional antenna comprises the substrate 21, the U-shaped metal grounding sheet formed by the rectangular metal sheet 1, the rectangular metal sheet 2 and the rectangular metal sheet 14, the rectangular metal sheet 15, the rectangular metal sheet 3, the bending line metal radiation structure formed by the rectangular metal sheet 4, the rectangular metal sheet 5, the rectangular metal sheet 16, the rectangular metal sheet 17, the rectangular metal sheet 6, the rectangular metal sheet 7, the rectangular metal sheet 18, the rectangular metal sheet 19, the rectangular metal sheet 8, the rectangular metal sheet 9 and the rectangular metal sheet 20, and the groove structure formed by the rectangular metal sheet 10, the rectangular metal sheet 11, the rectangular metal sheet 12 and the rectangular metal sheet 13. The single-chip rectangular omnidirectional antenna is used for indoor and outdoor wireless coverage occasions.