80results about How to "Low sidelobe" patented technology

The invention belongs to the technical field of microstrip transmission array antennas, specifically a four-beam microstrip transmission array antenna based on a super-surface, and a design method for the four-beam microstrip transmission array antenna. The antenna consists of a horn feed source and a super-surface microstrip transmission array. The horn feed source consists of a waveguide and a horn opening. The distance from the horn opening to the super-surface microstrip transmission array is set as F, and the diameter of the super-surface microstrip transmission array is set as D. The super-surface microstrip transmission array consists of N*N super-surface transmission units. Each super-surface transmission unit consists of three identical composite metal structures and two dielectric plates with the height h, wherein each composite metal structure consists of an I-shaped structure and metal pasters in complete left/right symmetry, and is used for achieving the coupling of two transmission modes in the same plane, thereby reducing the resonant frequency of the unit, and increasing the phase response slope and phase accumulation. The antenna is advantageous in that the antenna is low in side lobe, is high in gain, is balanced in wave beam, is light in weight, is low in cost, and is easy to assemble and integrate.

The invention discloses a high-gain low-sidelobe highly directive antenna based on an artificial medium structure, comprising a microstrip antenna array and a radome composed of a plurality of grooved cross metal strip artificial medium structures; the grooved cross metal strip structure is printed on a tellite and is used as the radome of the microstrip antenna array; the structure can be equivalent to a homogeneous medium with plasma frequency by rationally designing the cycle and size of the metal structure; the equivalent index of refraction of the frequency of the electromagnetic wave is similar to zero when the frequency is in a certain frequency band. The energy of the electromagnetic wave radiated by the microstrip antenna array is collected in the normal direction of the radome when the electromagnetic wave passes through the radome to achieve the effect of gathering energy, thus improving the overall directivity and gain of the antenna and reducing the sidelobe of the antenna. The antenna not only has the advantages of high gain, good directivity, low sidelobe and the like, but also has the characteristics of good mechanical performance, convenient fixed mounting, simple processing, low cost, small structure size and the like.

The invention provides a design method of a W-wave band single-pulse Cassegrain antenna. The design method comprises the following steps of: 1, determining diameter of a main reflecting surface of a Cassegrain antenna according to the demand of a target detection device on gain and caliber of the detection device; 2, determining a focal diameter ratio of the main reflecting surface of the Cassegrain antenna according to demands of the target detection device on the overall volume of the antenna and system noise; 3, determining the diameter and equation of a secondary reflecting surface of the Cassegrain antenna according to the demands of the target detection device on the side lobe of the antenna and 3bB wave beam width; 4, determining elongation and trumpet angle of a trumpet body at the front end of a feed source according to a single-pulse detection system and the secondary reflecting surface of the Cassegrain antenna; 5, determining a turning waveguide body at the rear end of the feed source of the Cassegrain antenna according to the demands of the target detection device on the feed source thickness and the rear end structure design; 6, designing a sum-difference network according to the single-pulse system and the feed source, and 7, assembling and forming the single-pulse Cassegrain antenna, and finally finishing design of the W-wave band single-pulse Cassegrain antenna.

The invention relates to a trapezoidal waveguide slot array antenna unit used for a communication system, which comprises a trapezoidal-section metal waveguide, radiating slots, a short circuit board, coaxial feeder equipment and adjusting screws, wherein the included angle between the two sloping sides of the trapezoidal section is designed as 45 degrees, and the length of broad side is twice as the height; and the radiating slots are alternately arranged on two sides of the broad side of the wave guide to adjust the section size and the slot length, thereby forming a array antenna unit capable of working at different frequencies. The antenna unit has the advantages of high gain, low side lobe and the like in the traditional waveguide slot array antenna unit, and can improve the antenna bandwidth as the number of the slots increases. The invention is easy to process and manufacture.

The invention discloses an MIMO communication system based on an irregular spliced sub-array architecture, which can be used for full-digital beam forming and hybrid digital beam forming. Each radio frequency link is connected with two adjacent antenna units through one power divider, so that the number of the radio frequency links can be greatly reduced. In the design process, firstly, irregularsub-array arrangement is optimized by taking MIMO channel capacity as an optimization target, and after an optimal array topological structure is obtained, precoding and decoding vectors are designedby taking spectral efficiency maximization as a target. The most innovation of the invention lies in that under the condition that the number of the radio frequency links is not changed, the irregularsubarray architecture improves the MIMO channel capacity by increasing the aperture area of the antenna array, and finally, the spectral efficiency is improved.

The invention discloses a robust low-sidelobe beam forming method based on the reconstruction of a covariance matrix. The method comprises the following steps of 1) sampling a received signal of a radar array to obtain a signal vector; 2) according to sampled data, figuring out the covariance matrix and the spatial spectrum distribution of received data, and reconstructing a covariance matrix of interference and noise; 3) according to the reconstructed covariance matrix and a guide vector, solving a MVDR model added with the auxiliary lobe constraint through a convex optimization method, and obtaining a global optimal weight vector; 4) multiplying the received signal vector with the obtained optimal weight vector to obtain a robust low-sidelobe self-adaptive beam. The self-adaptive beam forming method is good in robustness and low in sidelobe.

The invention discloses a sparse array method for a large-spacing wide-angle scanning millimeter wave phased-array antenna, and aims to provide a sparse array method which is simple and time-saving, large in unit spacing, macroscopically uniform in grids, low in side lobe, free of grating lobes and high in large-scanning-angle gain. According to the technical scheme, a rectangular coordinate system is constructed with a center of an array as an original point of coordinates, and the coordinate positions of antenna units are calculated according to Fibonacci grids; a helix angle growth coefficient is selected according to a wavelength corresponding to the working frequency of the antenna, and the position coordinates of n antenna units are calculated according to a helix formula with an unit of meter and Fibonacci number; based on the disordered arrangement of the annular sparse array, the number of Fibonacci grid antenna units is set, and the antenna units are aperiodically arranged byusing a Fibonacci spiral curve composition method; and n antenna units are spirally arranged along the Fibonacci to form a non-equidistant involute spiral large-spacing wide-angle scanning millimeterwave phased array which expands outwards at equal intervals according to an arc radius and is gradually far away from a circle center.

The invention discloses an integrated substrate gap waveguide circularly polarized slot traveling wave array antenna which comprises an upper dielectric plate, a lower dielectric plate and a spacer dielectric plate disposed between the upper dielectric plate and the lower dielectric plate. A first copper cladding layer is printed on an upper surface of the upper dielectric plate, a plurality of slit units spaced apart in a predetermined direction are etched on the first copper cladding layer, and each of the slit units comprises two rectangular slits whose length directions intersect and are not parallel to the predetermined direction, and a feeding microstrip line arranged in the predetermined direction is printed on a lower surface of the upper dielectric plate. Circular metal patches which are periodically arranged are printed on an upper surface of the lower dielectric plate, a second copper cladding layer is printed on a lower surface of the lower dielectric plate, each of the circular metal patches is provided with a metal through hole which passes through the lower dielectric plate, and the metal through hole is connected to the second copper cladding layer. According to theinvention, the disadvantages of complex structure and weak electromagnetic shielding performance of an existing circularly polarized traveling wave antenna can be overcome.

The invention discloses a sugar shovel-type fan-shaped horizontal beam scanning antenna. The sugar shovel-type fan-shaped horizontal beam scanning antenna comprises two metal plates (1), a horn antenna (2), a reflection surface (3), a transition structure (4) and a connection structure (5), wherein the connection structure (5) comprises a first connection part and a second connection part, the first connection part is formed by connecting one edge of the horn antenna (2) to one end of the reflection surface (3), the second connection part is formed by connecting the other edge of the horn antenna (2) to a side wall of the metal plate (1) where the other end of the reflection surface (3) is located, a radiation opening surface is formed between the second connection part and the other end of the reflection surface (3), one end of the transition structure (4) is connected to the metal plate (1) where the radiation opening surface is located, and the other end of the transition structure (4) extends towards a free space. By the sugar shovel-type fan-shaped horizontal beam scanning antenna, a fan-shaped beam can be obtained, the horizontal scanning function is finally achieved, energy leakage can be prevented, the energy utilization ratio can be relatively high, and the side lobe can be relatively low; and the antenna is relatively high in gain and relatively excellent in performance, and energy is relatively concentrated.

The invention relates to an inter-harmonic detection method based on a triangular-rectangular hybrid convolution window and an accelerated PSO algorithm. The method includes the following steps that:grid current/voltage signals are converted into secondary side discrete signals through a power transformer; a triangular-rectangular hybrid convolution window with the same length as the length of the signals is constructed, and is multiplied with the signals; the windowed signals are subjected to discrete Fourier transformation, and an appropriate spectral line construction interpolation formulais found in a frequency domain; and the parameters of all sinusoids in a local region are pre-calculated according to a conventional interpolation algorithm; and pre-calculation results are sorted into a matrix, and the matrix, adopted as initial particles, is substituted into the accelerated PSO algorithm. The particles are optimized by iteration, so that harmonic parameters with higher precision can be obtained. With the method adopted, the decomposition of spectra interfered by main lobes can be avoided; the pre-calculated solutions are optimized through an evolution type algorithm. Therefore, the method can stably improve detection accuracy and has high universality.

The invention relates to a communication device, a lens antenna and a spherical lens. The spherical lens comprises a dielectric carrier and a plurality of dielectric cones. The plurality of dielectriccones are uniformly arranged on the outer surface of the dielectric carrier. Each dielectric cone is provided with three wall surfaces, and every two of the three wall surfaces are connected to formthree edges with the same shape. An included angle between two surfaces formed by connecting any two edges with the central axis of the dielectric cone is 120 degrees, and the section, perpendicular to the central axis of the dielectric cone, of the dielectric cone is an equilateral triangle. Compared with a traditional mode that dielectrics made of different materials are laminated to adjust anddesign the dielectric filling ratios of different parts, the method has the advantages that a plurality of dielectric cones with the same shape are processed by adopting the same material, and the plurality of dielectric cones are uniformly arranged on the dielectric carrier, so that the manufacturing difficulty can be greatly reduced; the processing precision is high; the assembly is easy; and large-scale mass production can be realized.

The invention discloses a double-reflecting surface antenna with a special shape guided wave dielectric rod feeding. The antenna includes a circular waveguide, a guided-wave dielectric rod, a taperedsecondary reflecting surface, a parabolic reflecting surface, and a metal ring, wherein the guided-wave dielectric rod is located between the tapered secondary reflecting surface and the circular waveguide, the guided-wave dielectric rod is inserted to the inner cavity of the circular waveguide, the guided-wave dielectric rod located in the inner cavity portion of the circular waveguide is dividedinto a plurality of coaxial circular tables, and the radius of the circular tables decreases progressively in a direction from the tapered secondary reflecting surface to the parabolic reflecting surface; the circular waveguide is located at the center of the main reflecting surface, the axis of the circular waveguide and the diameter of the antenna point to the same direction, and a microwave signal is introduced by the circular waveguide, sent to the tapered secondary reflecting surface by the guided-wave dielectric rod and reflected to the parabolic reflecting surface, and finally emittedby the parabolic reflecting surface in parallel. The invention effectively improves the reflection coefficient S11 of the double-reflecting surface antenna, is capable of effectively suppressing the cross polarization, reducing the ohmic loss, reducing the sidelobe level, and improving the radiation efficiency, and is symmetrical in structure, compact and simple, and easy to implement.

The invention discloses a discretized region scanning subarray-level sparse optimization method and system, and belongs to the technical field of array antenna design, and the method comprises the following steps: S1, discretizing an initial population; s2, carrying out region scanning processing; and s3, optimization processing. When the method and the system are applied to sub-array-level sparseoptimization of a large-scale circular aperture antenna, under the condition that the sub-array spacing meets the spacing requirement, the optimization time is greatly reduced, the sidelobe level isreduced, a new way is provided for rapidly solving effective position arrangement of array elements under the specific array element spacing limitation condition, the diversity of a solution set in the optimization process is improved, the probability of finding the optimal solution is improved, and local convergence of the optimization algorithm is effectively avoided; and when the designed arrayantenna is applied to a large-scale radar system, the radar has the advantages of long operating distance, high resolution, low cost, light weight, high engineering realizability and the like, and isworthy of popularization and application.

The invention discloses a series-fed planar printing array antenna comprising an upper dielectric plate, an underlying dielectric plate, a microstrip radiation group, a metal ground layer and a microstrip feeder line. The microstrip radiation group comprises a first microstrip radiation unit, a second microstrip radiation unit, a third microstrip radiation unit, a fourth microstrip radiation unitand a fifth microstrip radiation unit. The working modes of the first microstrip radiation unit, the second microstrip radiation unit, the third microstrip radiation unit and the fourth micro microstrip radiation unit and the fifth microstrip radiating unit are in a magnetic dipole working mode, and are arranged in order from left to right according to the Taylor line rule. The microstrip feeder line is separately connected with the first microstrip radiating unit, the two microstrip radiation unit, the third microstrip radiation unit, the fourth microstrip radiation unit and the fifth microstrip radiation unit. The advantages are that based on a simple structure and a low profile, electromagnetic waves with low side lobes and capable of vertical polarization of transmit-receive are provided.

The invention discloses a phased array arrangement optimization method based on irregular subarrays. A mixed integer linear programming model is provided. Meanwhile, the gain and sidelobe level duringarray scanning are considered, solving is conducted through a commercial solver to achieve the high gain and low sidelobe characteristics during irregular array scanning, and after array arrangementis optimized, a needed directional diagram is synthesized with the maximum gain as the principle through a convex optimization algorithm.

The invention provides a low sidelobe radar antenna and a vehicle-mounted radar antenna. The low sidelobe radar antenna comprises a dielectric substrate, andN 45-degree polarized linear arrays whichare laid on the dielectric substrate. Each 45-degree polarized linear array comprises a feeder line and a plurality of array elements arranged on the feeder line. An included angle between each arrayelement and the feeder line is 45 degrees. N is a positive integer greater than or equal to 3. According to the invention, when the low sidelobe radar antenna is opposite to the same 45-degree polarization radar, the +/-45-degree polarization orthogonality can provide enough antenna isolation, and interference of an opposite coming vehicle or an opposite radar antenna is reduced to a great extent.

The invention discloses a phased array arrangement optimization method based on irregular subarrays. According to the method, the definition of array information entropy is fully utilized, and the array information entropy is applied to an irregular phased array based on a four-network grid form; and an optimization model is linearized by adding variables, so that an original problem can be solvedby a commercial solve; after array arrangement is optimized, a directional diagram of a required scanning angle is synthesized through a convex optimization algorithm. The method is most ingenious inthat the essential characteristics of the original optimization problem are mined; the convex optimization algorithm is adopted for optimization; and therefore, calculation time is greatly saved, anda super-large-angle scanning characteristic is guaranteed while only one fourth of the number of T/R components of an original array is used.

The invention provides a radiation patch array and a planar microstrip array antenna. The radiation patch array is composed of n columns of radiation patch linear arrays. The radiation patch linear array is composed of m rows of radiation patch units. The radiation patch unit comprises a cross-shaped power division network and two rectangular patches. The cross-shaped power dividing network is ofa four-port structure, a left port and a right port are respectively connected with a rectangular patch, and the rectangular patches are excited in a parallel connection mode. And the upper ports andthe lower ports are respectively connected with the upper ports or the lower ports of the adjacent cross-shaped power division networks in the same column in series. The radiation patch linear array excites the rectangular patches in a parallel series feed mode, constructive radiation superposition is achieved in the wide edge direction of the rectangular patches, the length of a transmission lineis reduced by one time, meanwhile, the size of the antenna is reduced, and the cost of the antenna is effectively reduced. Meanwhile, because the feed loss is reduced, the noise performance of the array is improved, and the radiation efficiency and the gain bandwidth performance of the array are improved.