37results about How to "Stable radiation characteristics" patented technology

The invention relates to a multi-frequency-band array antenna compact in structure. The multi-frequency-band array antenna comprises a metal reflective board, a low-frequency radiation unit working in low frequency bands and a high-frequency radiation unit working in high frequency bands, and the low-frequency radiation unit and the high-frequency radiation unit are arranged on the metal reflective board. The low-frequency radiation unit and the high-frequency radiation unit are arranged on the metal reflective board in a nested mode, and the orthographic projection of the low-frequency radiation unit and the orthographic projection of the high-frequency radiation unit do not coincide. The low-frequency radiation unit is formed by connecting a horizontal vibrator and a vertical vibrator with a power divider feed network and is flexible in structure, and a distance and other parameters can be flexibly configured according to practical application requirements. Due to the adoption of the structure, circuit network losses are few, the radiation characteristic stability of the multi-frequency-band array antenna within an ultra wide band range can be maintained, 2G, 3G and 4G LTE systems in mobile communication are compatible, the number of antennas used in a base station can be reduced, station distribution cost can be lowered, and operation and maintenance cost can also be lowered.

The invention discloses a broadband dual-polarization base station filter antenna unit without an external filter circuit and an array thereof. The antenna unit is arranged in the middle of the reflector. The antenna comprises an oscillator arm, a balun and two parasitic metal rings. The vibrator arm is provided with a microstrip line branch, is connected through the balun, and is fed through thebalun, and the balun is provided with a feeder line. The upper part and the lower part of the vibrator arm are respectively provided with parasitic metal rings. The antenna unit has the characteristics of compact and simple structure. The invention realizes good out-of-band rejection effect and has good frequency selectivity without cascading filter, thus avoiding filter insertion loss. The invention realizes high polarization isolation, and realizes stable pattern in wide frequency band at the same time.

The invention relates to a multi-band array antenna compact in structure. The multi-band array antenna compact in structure comprises a metal reflecting board, a low frequency radiation unit working in a low frequency band and a high frequency radiation unit working in a high frequency band. The low frequency radiation unit and the high frequency radiation unit are arranged on the metal reflecting board in a nested mode, and the orthographic projections of the low frequency radiation unit and the high frequency radiation unit are not overlapped. The low frequency radiation unit is formed by connecting a horizontal oscillator, a vertical oscillator and a feed network. A low frequency oscillator is flexible in structure, and parameters such as separation distances can be flexibly configured according to practical application requirements. By the adoption of the structure, the stability of radiation characteristics of multi-band frequency array antennas in an ultra wide band range can be kept, the multi-band array antenna compact in structure is compatible with all 2G, 3G and 4G LTE standards in mobile communication, the number of antennas used by a base station is reduced, station distribution cost is reduced, and operation maintenance cost can also be reduced.

The invention discloses broadband high-gain Vivaldi antenna which a dielectric substrate, a metal patch, a quadrangular metal patch, an impedance match microstrip line and a sector-shaped metal branch. The metal patch and the quadrangular metal patch are fixed in the top side of the dielectric substrate, the impedance match microstrip line and the sector-shaped metal branch are fixed in the bottomside of the dielectric substrate, the metal patch is provided with gradual-change trough line symmetric by taking the horizontal central axis as the center and provided with a horn-shaped opening, the gradual-change trough line is of index type gradual change, the bottom end of the gradual-change trough line is provided with a circular resonant cavity, the outer sidewalls of the gradual-change trough line are provided with comb shaped grids at equal interval, the quadrangular metal patch is positioned in the opening of gradual-change trough line, one end of the L-shaped impedance match microstrip line is connected to the sector-shaped metal branch, and the impedance match microstrip line and the sector-shaped metal branch serve as a feed structure. The Vivaldi antenna of the frequency range of 2.3-8.0GH is characterized by simple structure, wide frequency band and high gain.

Aiming at the problem that an existing antenna system with a dielectric lens does not consider a thermal expansion effect of the dielectric lens in a wide temperature range, the invention provides an antenna system having a gain auto-correction function. The antenna system comprises a substrate aluminum plate, a base, radiation antennas, a dielectric lens plate and a lifting device, wherein the base is arranged at the bottom of the substrate aluminum plate, the radiation antennas are arranged at the top of the substrate aluminum plate, the dielectric lens plate is arranged on the radiation antennas, the dielectric lens plate and the substrate aluminum plate are movably connected by the lifting device, and the relative distance between the dielectric lens plate and the radiation antennas is adjusted by the lifting device. The antenna system has the technical effects that a temperature change coefficient of the dielectric lens is adjusted by self-adaptive height adjustment, and the problems of gain fluctuation and beam change of the antenna system in the wide temperature range are effectively solved.

The invention provides an air filler metal planar array antenna and belongs to the technical field of array antennas. The air filler metal planar array antenna comprises an air power dividing network,wherein two transmission segments connected to each other in the air power dividing network form a T-shaped connection structure; electromagnetic energy is equally distributed in each T-shaped connection structure; the two ends of the last transmission segment are provided with first air vertical waveguides; the upper surface of each first air vertical waveguide is connected to an air cavity; four second air vertical waveguides are arranged centrally symmetrically on the air cavity; four radiating element individuals are centrally symmetrically distributed on the two sides of the long side ofthe two air vertical waveguides. The air filler metal planar array antenna is compact in structure, high in integration degree, small in space volume and easy to machine and realizes radiating elements with wideband radiation characteristics. The radiating elements and a feed network can be well matched, and the electromagnetic energy can be efficiently transmitted and effectively allocated in amultilayer metal cavity so as to ensure that the antenna has a wide frequency band, high gain and stable radiation characteristics.

The invention provides a low RCS array antenna with reconfigurable scattered beams. The low RCS array antenna comprises a dielectric substrate, N slotted metal floors printed on the lower surface of the dielectric substrate, N feed structures, N radiation patches printed on the upper surface of the dielectric substrate and N annular radiators, wherein the feed structure is composed of a metal column and a rectangular metal sheet; the annular radiator is composed of a rectangular metal ring, a metal patch, a PIN tube, a capacitor and an inductor; the PIN tube, the capacitor and the inductor areembedded in the rectangular metal ring; the rectangular metal ring is provided with M * N openings, and M is greater than or equal to 1, and the end parts of the openings are respectively connected with the PIN tube and the capacitor; and the metal patch is located on the outer side of the rectangular metal ring and connected with the rectangular metal ring through the inductor. The low RCS arrayanteena adjusts scattered wave beams through the rectangular radiation ring, guarantees that a high-gain effect is obtained under the condition that the radiation characteristic of the antenna array,and obviously reduces the radar scattering cross section of the antenna under the conditions of vertical incidence and oblique incidence.

The invention relates to a dual-frequency dielectric patch antenna with a frequency tunable function, which comprises a lower dielectric substrate, a metal reflection floor, an upper dielectric substrate and a rectangular dielectric patch which are sequentially stacked from bottom to top. A frequency tuning structure is arranged between the rectangular dielectric patch and the upper dielectric substrate, the lower surface of the lower dielectric substrate is provided with a microstrip feed line for coupling differential feed, and the metal reflection floor is provided with a coupling gap corresponding to the microstrip feed line. The invention provides a frequency-reconfigurable dual-frequency dielectric patch antenna working in a dominant mode TM10 and a high-order mode anti-phase TM20 for the first time. Because the sensitivities of the two modes to the length change of the dielectric patch are different, the electrical length of the dielectric patch is changed by embedding a pair of microstrip line parts loaded with variable capacitance diodes into the two sides of the rectangular dielectric patch resonator in a targeted manner, so that under the condition that the frequency and radiation performance of a main mode TM10 are not influenced, the frequency of the high-order mode inverted TM20 is independently tuned.

The invention discloses a Q-wave band ultra-high-speed wireless local area network mobile terminal antenna, which comprises a dielectric substrate, a rectangular metal antenna radiation unit, a short circuit branch metal strip, a feeder branch metal strip and a metal grounding plane, wherein the short circuit branch metal strip and the feeder branch metal strip are connected with the antenna radiation unit, a first metal through hole is formed in the short circuit branch metal strip, a second metal through hole is formed in the feeder branch metal strip, the area of the metal grounding plane covers the area of the antenna radiation unit, the short circuit branch metal strip and the feeder branch metal strip, and a U-shaped gap is formed in the rectangular metal antenna radiation unit. Compared with the prior art, the Q-wave band ultra-high-speed wireless local area network mobile terminal antenna has the advantages that by aiming at the characteristics of the millimeter wave frequency band (45GHz), a printed circuit process is utilized for designing and realizing the Q-wave band mobile terminal antenna with simple structure and small size, the antenna has the characteristics of broadband, small standing wave, omnidirectional radiation, easy integration, higher precision and good repeatability, meanwhile, the cost is low, the batch production is convenient, and the like.

The invention discloses a small ultra-wideband circularly polarized planar helical antenna, which comprises a self-compensating composite helical structure serving as a radiating element of the antenna and a microstrip gradient balun structure for feeding, wherein the microstrip gradient balun structure is a double-sided structure, two unbalanced microstrip lines are gradually changed into balanced parallel double lines, and impedance conversion is realized in the gradual change process; and the unbalanced end of the microstrip gradient balun structure extends downwards to a reflector. The small ultra-wideband circularly polarized planar helical antenna provided by the invention maintains a stable radiation property, the impedance bandwidth of the antenna reaches 150% (2-18GHz), a standing-wave ratio is less than 2, the antenna maintains an excellent circular polarization property in the working bandwidth (2-18GHz), and an axial ratio is less than 3dB. On the basis of ensuring the radiation property, impedance bandwidth and axial ratio bandwidth of the antenna, the plane size and profile size of the antenna are reduced, and the property of miniaturization is achieved.

The invention discloses a broadband Butler matrix feed network with frequency-variable phase difference. According to the invention, the working range of the feed network is 2-4 GHz, and the feed network is provided with four input ports, four output ports, two three-section couplers, four broadband couplers, three cross networks, two phase compensators, two 45-degree phase shifters and six broadband phase shifters, wherein two of the input ports are connected with a matched load, and the other two of the input ports feed independently; when a frequency is changed from 2 GHz to 4 GHz, signals with equal amplitude and with a phase difference that changes from +/- 45 degrees to +/- 90 degrees can be output; and a change process is close to a linear change, and the working frequency range of the feed network exceeds one frequency multiplication. According to the invention, phase difference frequency change is achieved through power synthesis, the radiation characteristic that an antenna array beam direction is stable is achieved, and the whole feed network is simple and compact in structure, easy to machine, light in weight, low in machining cost, wide in working bandwidth and good in application prospects.