44 results about "Beam broadening" patented technology

The invention discloses a beam broadening and sidelobe suppression method based on sparse constraint, belongs to the field of processing of antenna array signals receiving wireless transmission signals, and particularly relates to a method for utilizing sparse reconstruction for achieving beam broadening and sidelobe suppression to optimize an antenna array. A sparse constraint algorithm is utilized for achieving beam broadening, and meanwhile a low sidelobe level can be obtained, so that the restraining ability to interference signals is improved. An antenna array model is built, so that a guide vector parameter is determined; an over-complete dictionary is utilized for expressing a matrix of observation and interference direction information, a weight vector of a beam former is initialized, sparse iteration is carried out on the weight vector, the weight vector meeting the condition is obtained, and therefore an output peak value obtains a lower sidelobe on the original basis. Compared with other algorithms, the super-resolution is achieved while a narrow main lobe is achieved; stability is improved while the sidelobe is low.

The invention relates to the technical field of automobile lamp illumination systems, in particular to a light-guide-based low-high beam system and an automobile lamp. The low-high beam system comprises a collimating light-transmitting device and a light guide; the collimating light-transmitting device and the light guide are arranged in sequence in the direction of light beams emitted by a lightsource, the light emitting surface of the light guide is a convex surface, so that the light beams emitted by at least one light source are emitted out through the collimating light-transmitting device and the light guide sequentially, and light spots with upper beams and lower beams which are parallel and left beams and right beams which are diffused are formed. According to the scheme, one of alow beam broadening light type, a low beam inflection point light type or a high beam light type is achieved through the combination of the different light sources, and a plurality of functions such as the AFS and the ADB can be realized.

The invention discloses a common-aperture simultaneous transmitting multi-beam method for phased array radar, belongs to the technical field of the phased array radar, and particularly relates to a common-aperture simultaneous transmitting multi-beam forming method for digital array phased array radar. A transmitting terminal of an array antenna transmits two orthogonal code wave signals which are linearly superposed after phase weighting, the signals are amplified through a linear power amplifier and then transmitted out through antenna array elements, and beams with different directions can be obtained. A receiving antenna receives signals reflected by a far field object, matching processing is conducted on the signals through a matching filter, and two transmitting signals can be separated out. Thus, the method has the advantages that during radar detection, a dead zone is small, beam broadening caused by subarray segmentation is avoided, and the method is particularly suitable for multi-object detecting and tracking of short ranges and medium ranges of the phased array radar.

A femtosecond laser system for ophthalmic applications, which employs a number of chirped mirrors in the laser beam delivery system between the laser head and the objective lens. The chirped mirrors perform the dual function of both turning the laser beam in desired directions and compensating for beam broadening due to group delay dispersion (GDD) of the optical elements of the system. Each chirped mirror reflects the laser beam only once. Four chirped mirrors are used, each providing up to −5000 fs² of negative GDD per bounce, to provide a total of −18,000 fs² negative GDD to compensate for the positive GDD of +18,000 fs² introduced by other optical elements in the laser beam delivery system. This eliminates the need for a pulse compressor that would employ a grating pair, prism pair or grism pair, and therefore significantly reduces the size of the system and the alignment requirements.

The invention discloses a broad-axial-ratio-beam antenna loaded by a single dielectric, comprising a loading dielectric and a circularly polarized patch antenna. The loading dielectric comprises a dielectric block and an air cavity formed by hollowing the bottom surface. The circularly polarized patch antenna comprises a circular patch, a first dielectric plate, a floor, a second dielectric plateand a single-frequency feed network arranged in turn from top to bottom. The single-frequency feed network comprises a single-frequency branch line coupler, a feed probe, a grounding short circuit pinand a matching resistor. Because a loading dielectric design of a special structure is adopted, the traditional circularly polarized patch antenna achieves a good axial ratio beam broadening effect.In addition, the antenna has the advantages of simple structure, stable gain and small size, and is very suitable for wide application and promotion.

An X-band wide beam circularly polarized antenna for a lunar rover mainly and structurally comprises a high-frequency coaxial socket (50 Omega, SMA or TNC), a coaxial waveguide converter, a circular polarizer, an antennal shield with a beam broadening device and an antenna support. A high-frequency signal is fed via a high-frequency cable and is converted into a waveguide transmission signal via the coaxial waveguide converter, and a linear polarization signal is converted into a circular polarization signal via the circular polarizer. Electromagnetic waves are radiated from a waveguide aperture, the beam is broadened via the antenna shield, and a circular polarization directional diagram is formed. The X-band wide beam circularly polarized antennal overcomes detects that the beam width of the conventional antenna is not enough, the back lobe of a wide beam antenna is higher, and the antenna is easily interfered by the environment. The omnidirectional directional diagram of the antenna can satisfy demand of the rover for ground communication with various poses, and very low back lobe radiation lowers the influence of the rover mounting environment on the radiation performance of the antenna.

A system and method to provide maximum power over large angular sectors using an array of transducers is disclosed. Array segments of transducers and phase shifters form a beam from each of the array segments, wherein the set of beams overlap to form a large sector coverage beam. The phase of each of the signals fed to the radiating elements is shifted, such that the difference between beam point directions of the beams of two adjacent array segments is substantially equal to one half of the sum of the beamwidths of the beams of the two adjacent array segments. The phase of each of the signals fed to the radiating elements may also be shifted in proportion to the square of the distance between one end of the array of transducers and the position of each of the plurality of radiating elements.

The invention discloses a wide-beam plane lens antenna with variable beam width. The antennacomprises a horn feed source antenna and a plane lens, and the plane lens realizes the refraction of electromagnetic waves by setting a gradient phase, wherein on the basis of compensating a space phase caused by an optical path difference, an additional gradient phase delta n is added on the H surface of the antenna, the plane lens is composed of 51*51 phase shift units, each phase shift unit adopts two layers of media, the surfaces of the upper layer, the middle layer and the lower layer are coated with copper, and the thickness is very thin. In order to simplify the design and reduce the processing cost, eight phase shift units are selected to cover a phase shift range of 0-360 degrees. A beam broadening phase is introduced to enable the focusing performance of the lens on two main planes to be different so as to control the beam width, the phase shift required by each position is obtained according to a calculation formula of each point of the plane lens, and the phase shift units are arranged according to a specified phase distribution diagram to obtain the plane lens antenna with the specified beam width.

The invention provides a self-adaptive beam width multi-beam forming method for an inclined array plane, which comprises the following steps of: performing traversal search on an airspace coverage range by adopting an azimuth multi-beam pitching scanning mode, and performing matching compensation on a pitching directional angle according to a vertical wave width of a pitching direction where transverse multi-beams are positioned; and keeping the horizontal wave width of each wave beam in the horizontal direction of the same pitching layer to be the same as the horizontal wave width of the wave beam in the azimuth method of the layer through a Taylor window coefficient broadening method. According to the method, space resources for receiving multiple beams at different pitch angles of the phased array plane are fully utilized, beam broadening is performed only in the horizontal dimension, directional diagram distortion of side beams is reduced as much as possible on the premise that the airspace coverage requirement of a geodetic coordinate system is met, and the direction finding precision of the array plane is improved.

The invention discloses a beam broadening algorithm based on inheritance quasi-global segmentation search, and the algorithm comprises the steps: S1, calculating the broadening multiple of a to-be-optimized directional diagram in a to-be-optimized directional diagram, and sorting the to-be-optimized directional diagram according to the broadening multiple; S2, calculating a ratio of broadening multiples between two adjacent to-be-optimized directional diagrams, inserting a virtual to-be-optimized directional diagram between the two adjacent to-be-optimized directional diagrams according to a preset target index when the ratio is judged to be greater than or equal to a constraint threshold, and recording the virtual to-be-optimized directional diagram as a revised to-be-optimized directional diagram; S3, calculating and revising universal amplitude distribution of the directional diagram group to be optimized according to the Taylor function; and S4, according to the phase excitation calculation formula, calculating and revising the phase excitation of the to-be-optimized directional diagram by adopting a sectional search algorithm. By means of the technical scheme, the optimizationefficiency of the directional diagram is improved, the calculation requirement for quick beam broadening in the array antenna is met, and the array antenna has the continuous beam characteristic.

The invention discloses a multi-objective optimization array pattern synthesis method based on an improved genetic algorithm, and belongs to the field of antenna array pattern synthesis. According to the method, the genetic algorithm is improved and optimized, and in order to avoid local convergence and prevent close-to-close combination, the Hamming distance is introduced to carry out close-to-close discrimination; in order to improve the convergence speed and ensure that an excellent mode in a parent body can be inherited to the next generation, the size of a crossover operator is adaptively determined according to the fitness. According to the method, a mutual coupling effect between array elements is considered, an active unit directional diagram is combined, an accurate antenna array model is constructed, different fitness function parameters are set for different target array directional diagrams, and an improved genetic algorithm is used for performing multi-target rapid optimization on the antenna array directional diagrams; finally, array synthesis such as beam broadening, low sidelobe, beam null, phased array scanning and the like is realized, and verification is carried out through full-wave electromagnetic simulation software.

The disclosure provides a wide field of view laser signal input optical fiber apparatus and method based on a higher-order phase. The apparatus is arranged at a feeding source of an optical system andcomprises a converting device and a target optical fiber, wherein laser signals of a wide field of view insert the higher-order phase in the space through the converting device and are input to the target optical fiber, and the higher-order phase is second order and or more. A wide field of view laser signal input optical fiber method based on the high-order phase is further provided based on theapparatus. According to the apparatus and the method, the laser signals insert the higher-order phase in the space so that the laser signals of the wide field of view are input to the target opticalfiber, and the wave beam broadening function is realized.

The invention relates to a beam broadening method based on an additional arc-shaped phase surface and belongs to phase change methods. Phase difference corresponding to the arc-shaped phase surface iscalculated, and the phase difference is directly overlapped into the spatial phase difference corresponding to an original beam pointing direction, so that beam broadening can be realized; cyclic iteration in beam forming is avoided, and the problem that the beam broadening degree is difficult to quantify is also solved; the method is simple, parameter debugging is easy, the real-time performanceis good, the universality is high, and engineering implementation is facilitated.

The invention discloses a beam broadening device of a broadband array antenna. The beam broadening device comprises at least four antenna units, at least one low-pass filter, at least one phase matching unit and only one power divider. The antenna units are arranged along a straight line to form a one-dimensional array antenna; the one-dimensional array antenna adopts an unequal-interval arraying mode; the minimum array pitch D in the entire array antenna is less than the high-frequency wavelength [lambda] H. Each edge antenna unit is connected with a low-pass filter; the low-pass filter is used for realizing gradient feed amplitude weighting; each central antenna unit is connected with one phase matching unit; the phase matching unit is used for compensating a phase error caused by introduction of a low-pass filter; and the power divider is used for synthesizing the output signals of all the antenna units together to form the broadband array antenna. The low-frequency gain and the high-frequency beam width of the broadband array antenna can be met at the same time.