310 results about "Directivity" patented technology

The invention relates to an ultrasonic phased array full-focusing imaging method for acoustic wave multi-path propagation compensation of a layered composite material, which is characterized by comprising the following steps of: arranging an ultrasonic phased array probe with N array elements on a composite material piece to be detected, obtaining complete echo data by taking each array element as a transmitting array element and taking all array elements as receiving array elements in sequence in a full-matrix acquisition mode; a two-dimensional pixel grid is established in an imaging area, a Monte-Carlo perturbation mechanism used for representing the acoustic wave propagation uncertainty in the layered composite material is introduced into a propagation model for each emission array element-receiving array element-pixel point combination, and the acoustic beam emission direction, the propagation path and the equivalent acoustic velocity are subjected to random perturbation, so that the acoustic wave propagation uncertainty in the layered composite material can be represented. Generating a plurality of equivalent sound wave propagation paths, calculating two-way propagation time of each path, and performing weighted statistics on energy contributions of different paths according to array element sound beam directivity to obtain equivalent propagation time delays of pixel points; and performing delay correction on a full-matrix echo signal by using the equivalent propagation time delay, and performing coherent superposition on signals of all transmitting-receiving array element combinations to realize dynamic focusing of a full-pixel grid, and finally reconstructing an ultrasonic full-focusing imaging image with high resolution and high signal-to-noise ratio. The time delay error caused by propagation path deviation and sound velocity non-uniformity in the layered composite material can be effectively compensated, the focusing precision and spatial resolution of full-focusing imaging are improved, meanwhile, an existing TFM imaging frame does not need to be changed, and the method has good engineering implementability and popularization and application value.

The invention relates to the technical field of chip preparation, and provides a chip based on an annular photonic crystal and a preparation method thereof. The preparation method comprises the following steps: growing a nucleating layer on a substrate; growing a superlattice structure on one side, away from the substrate, of the nucleating layer; sequentially growing an n-type coating layer, an n-type waveguide layer, a quantum well and a p-type electron blocking layer on one side, deviating from the nucleating layer, of the superlattice structure; etching a plurality of annular cavities on the p-type electron barrier layer to form an annular photonic crystal; growing a p-type extension contact layer on one side, deviating from the quantum well, of the p-type electron blocking layer; and carrying out in-situ annealing treatment. According to the preparation method, the directivity of the photonic band gap can be effectively adjusted, uniform light waves in all directions on the side face can be formed, so that leakage of laser from a non-light-emitting area on the side face is restrained, the light emitting efficiency is improved, the annular photonic crystals are periodically distributed, and the light beam quality is effectively guaranteed.

The invention discloses an unmanned aerial vehicle countering method and countering device for radio detection, and relates to the field of signal processing, and the method comprises the steps: scanning and capturing a transient radio frequency pulse signal through a radio frequency receiving array, carrying out the time-frequency domain conjoint analysis, constructing a signal intensity space distribution matrix, and extracting a parameter set; matching with a protocol feature library, identifying an unmanned aerial vehicle remote control link protocol type, and calculating an unmanned aerial vehicle position and a threat level in combination with a signal time difference of arrival and a frequency difference; generating adaptive interference signal parameters according to the protocol type and the threat level; the method comprises the following steps: generating a directional beam through a two-dimensional phased-array antenna, focusing the position of an unmanned aerial vehicle to transmit an interference signal, monitoring signal intensity change and protocol response delay in real time, calculating a communication suppression ratio, and iteratively optimizing an interference strategy until a suppression threshold is reached. The method has the advantages that efficient and accurate signal capture and interference are realized through multi-channel radio frequency detection, accurate positioning and adaptive interference technologies, and the countering efficiency and adaptability are remarkably improved.

The invention discloses a semiconductor defect detection method and device, and the detection method comprises the steps: controlling the bright field illumination and the objective magnification, and obtaining the surface microstructure morphology of a to-be-detected sample; determining the process type of the sample to be detected based on the surface microstructure morphology, and automatically determining dark field illumination light intensity parameters of at least two groups of dark field light sources according to a preset mapping relation between the process type and the dark field illumination light intensity parameters; according to the tissue morphology of the sample, at least two dark field light sources with different incident angles are controlled to carry out dark field illumination on the sample to be detected from different directions, and scattered signal images corresponding to different dark field angles are obtained through at least two detectors respectively; and analyzing defect information of the to-be-detected sample based on the scattered signal images at the dark field angles. The detection method can be adaptive to defect detection of different process sheet types, can effectively improve the detection precision of defect diversity and directivity, improves the detection signal-to-noise ratio, and efficiently detects multiple different types of defects at the same time.

The invention relates to a non-Lambert surface emissivity inversion method, belongs to the technical field of infrared optical measurement and radiation modeling, solves the technical problems of low precision and poor model stability of non-Lambert surface emissivity inversion, and comprises the following steps: measuring original radiation intensity of a non-Lambert surface of a to-be-tested material in different emergent directions; converting the original radiation intensity into directional reflectivity; on the basis of the generalized Lorentz function, diffuse reflection background items are superposed, and a physical prior model is constructed; physical constraint is carried out on the physical prior model parameters; the parameter residual network generates a parameter field, and the parameter field is input into the optimized physical prior model; and carrying out hemispherical integration, and converting the directional reflectivity into directional-hemispherical emissivity. The device and the method are used for infrared thermal imaging measurement, material radiation characteristic characterization and engineering detection in a complex environment.

Apparatus for paging for highly directional systems. A WTRU receives a default and / or a dynamic set of active SSBs which indicates the beams / SSBs is used to receive paging DCI, e.g. DCI scrambled with P-RNTI, over PDSCH. A WTRU utilizes the default and / or dynamic set of active SSBs in order to determine PDCCH monitoring occasions, PMOs, that are monitored in the WTRU's paging occasions, POs. A WTRU sends paging activating requests to activate a suitable SSB using associated UL signal / resources, if the suitable SSB fulfills a SSB criteria, if the activation duration has elapsed and if the monitoring duration has elapsed. A WTRU may send one or more paging activation requests to activate multiple SSBs, e.g., a field of view, FOV, around a suitable SSB. Said paging activation requests implements a minimal feedback-based paging procedure for paging in highly directional systems, to which the gNB replies with paging configuration for the suitable SSB.

The invention discloses a low RCS broadband array antenna based on modification processing and a wave absorbing material and a design method of the low RCS broadband array antenna. The design method comprises the following steps: firstly, designing an ultra-wideband Vivaldi antenna working in an X wave band; then analyzing the radiation and scattering surface current distribution of the antenna in the X wave band, and carrying out shaping processing on the antenna according to a simulation result; performing array design on the designed antenna to form an array antenna; and finally, analyzing the surface current in the radiation and scattering states of the array antenna, covering a higher scattering current area with a wave absorbing material, and reserving a high radiation current area of an antenna slot line area so as to reduce the RCS and reserve the radiation performance of the antenna. The low RCS broadband array antenna is designed by adopting the design method. According to the invention, the design requirements of high gain, high directivity and low RCS of the broadband array antenna are met, the effects of in-band RCS reduction, radiation performance maintenance and multi-angle reduction are considered, and the application of the antenna is expanded.

The invention discloses a fault cable rough measurement positioning auscultation system and method based on a vector microphone. The system comprises a sound acquisition unit, a circuit board and a power supply unit, wherein the sound acquisition unit is used for acquiring a detection signal of a cable, and the circuit board is connected with the sound acquisition unit and is used for processing the acquired detection signal to obtain a rough measurement positioning result of a cable fault. According to the scheme, cable discharge sound waves can be picked up to the maximum extent through direct contact with the cable, attenuation of sound in cross-medium transmission is reduced, and sound information is picked up through the two sets of high-directivity vector microphones according to the characteristic that the transmission loss of the sound in the same medium is minimum aiming at faults of the calandria cable, so that the transmission efficiency of the calandria cable is improved. The direction of the fault point is judged through operation of the circuit board, the range of the fault point can be quickly positioned only by repeatedly detecting the cable wells closest to the two sides of the fault point after the minimum range of the fault point is positioned, manpower and material resources are greatly saved, and the positioning time is shortened.

The utility model provides a waveguide antenna structure with a frequency selective surface structure and a waveguide radar, and the structure comprises a waveguide antenna which is provided with a waveguide slot array and a frequency selective surface structure; the waveguide slot array is arranged on the waveguide antenna in a penetrating manner, and the frequency selective surface structures are distributed on the peripheral side of the waveguide antenna; the frequency selective surface structure comprises surface structure units, and the frequency selective surface structure is formed by arranging a plurality of surface structure units. According to the utility model, the frequency selective surface structure absorbs reflection between the top surface of the antenna and the antenna housing and reduces distortion of a directional diagram; surface waves can be reduced, space coupling between the antennas is reduced, and the isolation between the antennas is improved; the beam directivity can be adjusted, and beam performance specific directivity can be shaped.

The invention relates to the technical field of coupler design, in particular to a bi-directional coupler applied to a high-frequency RFID (Radio Frequency Identification Device) system, which comprises the following steps: S1, respectively constructing a series transformer, a parallel transformer and a Magic-T structure hybrid network, and forming an impedance self-matching coupler core framework by adopting a plurality of Ni-Zn ferrite double-hole magnetic rings; s2, inputting an original coupling signal output by the coupler core architecture into a phase-amplitude cooperative calibration module to generate a calibrated stable coupling signal; s3, inputting the stable coupling signal into a bridging T-type attenuation network group, respectively performing accurate power adjustment on a forward coupling path and a reverse coupling path, and finally outputting a high-directivity and low-fluctuation coupling signal; s4, monitoring the impedance state of an antenna port in real time, and feeding back and adjusting a matching network structure to realize stable control of the standing-wave ratio in a full frequency band range; according to the invention, the design of an external matching circuit is simplified, the coupling efficiency and directivity are improved, and the method has important engineering value.

The present application relates to the technical field of channel prediction, in particular to a field strength prediction method and system based on short wave broadcasting, comprising the following steps: acquiring frequency sequence data, calculating jump rate, labeling predetermined jump characteristic frequency band, combining geographical and ionospheric elements to identify path height variation, extracting reflection angle and power change mapping deformation area, and superimposing directivity and strain intensity to predict field strength interval map. In the present application, by synchronously associating geographical space and ionospheric state elements on the basis of frequency sequence feature recognition, the trend of reflection path height variation is mapped through frequency jump behavior, field strength prediction value extraction and directivity attenuation superposition processing under spatial grid granularity are realized, multi-source correlated data is used as support to calibrate the field strength distribution interval of the prediction area, the adaptability and prediction resolution of field strength evaluation under non-static propagation conditions are enhanced, and a prediction framework with time-varying recognition, path feedback and power decrement linkage capability is constructed.

The invention discloses an SAR (Synthetic Aperture Radar) water depth inversion method based on a self-adaptive elliptic window function, which comprises the following steps of: realizing self-adaptive adjustment in the direction of an elliptic window, the proportion of a long axis to a short axis and the type of a window function by analyzing the energy distribution characteristics of a main peak of a two-dimensional frequency spectrum of an SAR sub-graph; therefore, the directivity expression of the spectrum main peak and the accuracy of wavelength extraction are remarkably improved. According to the method, the definition of the main peak of the frequency spectrum and the water depth inversion precision can be remarkably improved, and a more stable and accurate technical path is provided for SAR water depth inversion in a complex near-shore environment.

This invention provides an artificial surface plasmon full-space beam scanning leaky antenna, comprising a dielectric substrate. The upper and lower surfaces of the dielectric substrate form a top layer and a bottom layer, respectively. The top layer of the dielectric substrate has a balun structure, an artificial surface plasmon strip group, and several metal stubs. Balun structures are symmetrically arranged at both ends of the artificial surface plasmon strip group. Several metal stubs are periodically arranged and symmetrically arranged on the upper and lower sides of the artificial surface plasmon strip group. The artificial surface plasmon strip group includes a pair of slidingly symmetrical artificial surface plasmon strips. This invention enables continuous scanning of the main beam from back-firing to front-firing, possessing full-space beam scanning capability. It has advantages such as small bandwidth occupation, high radiation efficiency, high directivity, high gain, low profile, and relatively small overall size, and can be applied in wireless communication fields such as automotive radar.

The utility model discloses an adjustable directivity and portable installation structure of sound equipment, which comprises a fixed plate fixedly installed on the indoor top, the bottom of the fixed plate is rotatably connected with a support shaft, and the bottom of the support shaft is provided with a support hollow sphere. According to the utility model, under the interaction of the fixing plate, the supporting shaft, the supporting hollow sphere, the arc-shaped opening, the mounting cylinder, the sound equipment body, the longitudinal adjusting mechanism, the reinforcing mechanism and the transverse adjusting mechanism, the transverse adjusting mechanism is matched with the longitudinal adjusting mechanism, so that the transverse and longitudinal angles of the sound equipment body can be flexibly adjusted, and the sound coverage requirements in different scenes can be met; a reinforcing mechanism composed of an arc-shaped groove and an arc-shaped limiting plate improves the sliding stability of the installation cylinder and reduces shaking during adjustment, the speed reduction design of gear transmission enables the adjustment process to be more accurate and labor-saving, the overall structural design is reasonable, operation is convenient and fast, the adjustment precision, stability and use convenience are considered, and the use effect and the installation experience of the sound box are effectively optimized.

The invention discloses a self-powered reconfigurable metasurface control system and method based on space-time regulation and control. The self-powered reconfigurable metasurface control system comprises an external wireless center and a plurality of execution units. The external wireless center is used for generating a downlink control signal corresponding to the state required by the execution unit; the execution unit comprises a radiation layer and a control layer which are stacked; the radiation layer comprises a first antenna path and a second antenna path; the first antenna path is used for processing a downlink control signal to provide stable energy supply and a unified clock / synchronization reference for the second antenna path; the second antenna path extracts a state sequence in a downlink control signal and controls the on-off state of a diode in a control layer through the extracted state sequence under a unified clock provided by a peripheral support circuit, so that the control and directional reflection type communication requirements of high space-time modulation requirements are met, and the communication efficiency is improved. Therefore, the metasurface array can accurately regulate and control the frequency, the phase and the direction of the incident electromagnetic wave under the wireless architecture.

A differential feed dual-polarization super-directivity array antenna comprises a plurality of array units, and each array unit comprises a supporting structure, a main radiator, a metal floor and a radiation parasitic structure. The metal floor is arranged below the supporting structure, the main radiator is arranged in the supporting structure, the radiation parasitic structure is arranged above the supporting structure, and the main radiator is connected with a metal coaxial connector arranged on the metal floor through the feeder line structure. According to the invention, a dual-polarization radiation mode is realized by adopting two pairs of differential port feed structures, and an array design scheme with a super-directivity characteristic can be realized under two polarizations, so that the directivity upper limit value of a traditional aperture antenna scheme is broken through, and the capacity and the performance of a communication system are remarkably improved.

A device (100) for heating by electromagnetic waves comprises: an electrically conductive housing (1); an electromagnetic wave generation unit (10) that generates electromagnetic waves which are linearly polarized waves; a plurality of radiating units (3) that radiate the electromagnetic waves generated by the electromagnetic wave generation unit into the interior of the housing; a directivity control unit (2) that controls the directivity of the electromagnetic waves from the plurality of radiating units; and an electromagnetic wave absorbing unit (5) that is arranged inside the housing in such a way that the electromagnetic wave absorbing unit is aligned with a plane of oscillation of the electromagnetic waves and absorbs electromagnetic waves inside the housing.

The invention discloses a photovoltaic power generation antenna with a microwave receiving function, and relates to the technical field of antennae, the photovoltaic power generation antenna comprises an antenna main body and an antenna mounting bracket, the antenna main body is of a paraboloid structure, and a photovoltaic power generation assembly and a microwave receiving assembly are arranged on the paraboloid of the antenna main body. The antenna perfectly inherits the advantages of high gain and strong directivity of a parabolic antenna, directly faces high-performance application scenes such as satellite signal receiving, creatively provides a layered coplanar structure in which a metal net covers a photovoltaic battery piece, the metal net serves as a reflecting surface of microwave signals, and the metal net serves as a reflecting surface of the microwave signals. Meanwhile, the net structure allows sunlight to be transmitted to the photovoltaic battery piece on the lower layer, physical integration is achieved, one-face double-work is further achieved, the same paraboloid is an efficient light energy collecting face and a high-performance microwave signal reflecting face, and the possible defects of a planar integrated antenna in gain are overcome.

The invention discloses a high-gain spatial directivity construction method of a single-vector hydrophone, and relates to the technical field of underwater acoustic signal processing. Acquiring a sound pressure signal and a three-dimensional vibration velocity signal of the target area by using a three-dimensional vector hydrophone; equally dividing the orientation guide angle of the three-dimensional vector hydrophone to obtain a plurality of guide directions; for each guide direction, extracting a horizontal vibration velocity component in the three-dimensional vibration velocity signal, and obtaining two paths of dipole combined vibration velocity signals in each guide direction according to the horizontal vibration velocity component; performing synthetic convolution operation according to the sound pressure signal and the two paths of dipole combined vibration velocity signals in each guide direction to obtain a plurality of synthetic convolution combined signals in each guide direction; and according to the response of all the synthetic convolution combination signals in each guiding direction, obtaining the corresponding synthetic convolution combination directivity. According to the invention, high-gain high-order combination directivity is constructed, and the stability of the detection precision of an underwater weak target is improved.

To provide an antenna device which widens an angle of radiation directivity of a radio wave while suppressing an increase in size, and improves a gain of the radio wave in an orthogonal direction.SOLUTION: An antenna device includes an element surrounding portion made of a dielectric material and including a quadrangular prism-shaped recessed portion defined by a bottom surface on which a radiating element is disposed and four side surfaces surrounding the radiating element when viewed in a direction orthogonal to the bottom surface, and a ground layer disposed on a side opposite to the bottom surface. And a power supply unit that supplies power to the radiating element, wherein at least a part of each of two side surfaces facing each other along a deviation direction from the center to the position among the side surfaces is covered with a metal layer.SELECTED DRAWING: Figure 1

The sound collection system (S) has: a microphone array (1) including a plurality of microphones (2); a first beamformer (152) that outputs a first signal in which, among a plurality of sound signals based on sound arriving at the plurality of microphones (2), sound signals based on sound arriving from a direction within a first range are emphasized more than sound signals based on sound arriving from other directions; a second beamformer (153) that outputs a second signal in which, among the plurality of sound signals, sound signals based on sound arriving from a direction within a second range are emphasized more than sound signals based on sound arriving from other directions; a sound source direction detection unit (151) that detects a direction of a sound source that generates sound arriving at the plurality of microphones (2); and a directivity control unit (155) that, during the first beamformer (152) is outputting the first signal, if a change angle per unit time of the direction of the sound source detected by the sound source direction detection unit (151) is determined to be above a threshold value, causes the second beamformer (153) to output the second signal.

The invention discloses a quasi-single-mode circular waveguide conical horn antenna, a radar and a communication device. The quasi-single-mode circular waveguide conical horn antenna comprises a circular waveguide section and a conical horn section. Conductor loss is reduced by remarkably increasing the diameter of the circular waveguide, and axial periodic annular grooves are formed in the inner wall of the circular waveguide to form a spatial mode filter and a selective attenuation high-order mode, so that high radiation efficiency and high mode purity are realized at the same time in a millimeter wave frequency band. And the conical horn section adopts an index profile to realize high-directionality radiation. The antenna structure effectively solves the technical problems of large loss and impure mode in a millimeter wave high-frequency band in the traditional design.

The present application discloses a VVC multi-directional motion refinement optimization method based on a Merge mode from the VVC inter prediction with a Merge process with a motion vector difference, which only has a small part of coding units (CUs) to search in a large step, and fails to consider the multi-directionality of the motion in the actual process. First, the first two MV information in the extended Merge candidate list is selected as the initial MV, and is expanded from four step lengths and eight directions; it is judged whether the current step length index is greater than 1, if yes, skip the chroma block motion compensation and the bi-directional optical flow prediction mode; otherwise, skip the chroma block motion compensation, and after the optimal Merge mode is obtained, entropy coding is carried out. Compared with the VVC coding standard, the average bit rate of Y, Cb and Cr is saved by 0.57%, 0.62% and 0.25% respectively by the VVC multi-directional motion refinement optimization method based on the Merge mode.

A measuring device capable of performing pairing with an intended information terminal. A blood pressure monitor includes: a communication unit configured to communicate by a communication method that enables pairing; a processor; and a housing adapted to accommodate the processor and the communication unit. An antenna of the communication unit has directivity in a first direction that is larger than directivity in a second direction other than the first direction and is largest. An information display section from which first information can be acquired by imaging is provided on a side surface among outer surfaces of the housing, the side surface including an intersection with a virtual line extending from the antenna in the first direction. When the processor receives a signal including information based on the first information and a received strength of the signal is at a threshold or greater, the processor starts processing necessary for pairing.

This product is a flap for controlling the directivity of an antenna. It has flanges on both sides that rise in the direction of the antenna, and a directional control unit that is movably attached to the flange, as shown in the reference diagram showing the movable state. By moving the directional control unit, the antenna reading area can be freely changed.

The invention relates to the technical field of motion detection, and discloses a primary motion detector based on a PN junction channel, a preparation method and a sensor, the primary motion detector comprises a first photoelectric transistor and a second photoelectric transistor; the first phototransistor is configured to work under source-drain positive bias voltage, and the attenuation process of light current during turn-off has a first fast attenuation time constant and a first slow attenuation time constant; the second phototransistor is configured to work under the source-drain reverse bias voltage, the photocurrent of the second phototransistor when the second phototransistor is turned off has a second fast decay time constant and a second slow decay time constant, and the first fast decay time constant is larger than the second fast decay time constant; a directional current pulse can be detected at the output of the primary motion detector when the light pulse moves in the direction from the first phototransistor to the second phototransistor. According to the invention, high-efficiency and low-power-consumption discrimination of the optical signal direction is realized.

The present invention relates to a substrate comprising a patterned optical waveguide, the substrate comprising: an optical waveguide formed on the substrate with directionality and extending in at least one direction; and a quantum dot layer formed on a surface of the optical waveguide, wherein the quantum dot layer comprises quantum dots dispersed in an organic medium.

In one embodiment, a method includes determining character directivity index (DI) pattern data corresponding to a position of a listener based on sound production recorded by a microphone at each of a plurality of speakers. The method further includes extracting a set of DI features from the DI pattern data; providing the set of DI features to a trained machine learning model; and determining an arrangement of each of the plurality of speakers relative to the listener by the trained machine learning model and based on the set of DI features.

This subject provides an RFID device configured to improve the gain and directivity of an antenna. [Solution] The RFID device comprises an antenna, a metamaterial (MTM) array, and a substrate. The substrate has a first surface and a second surface, and the antenna has a bottom surface and an top surface. The bottom surface of the antenna and the MTM array are formed on the first surface of the substrate. The antenna and the MTM array are separated by a gap. The antenna is formed of a first conductive material defining a region enclosed by a first boundary line. The antenna has nested slots. The MTM array is formed of a second conductive material defining a region enclosed by a second boundary line.

The application discloses an end-fire antenna, comprising an antenna board, at least two sub-antennas are arranged at the top end of the antenna board, a feed network layer is arranged at the bottom end of the antenna board, at least two feed columns are arranged in the antenna board, the feed columns correspond to the sub-antennas one by one, the feed columns penetrate through the antenna board and connect the sub-antennas and the feed network layer. The feed network layer transmits high-frequency current to the corresponding sub-antennas through the feed columns, matches the required amplitude and phase for the sub-antennas, and finally converts the high-frequency current into electromagnetic waves, forms strong directional end-radiation in space, and makes the end-fire antenna have good end-fire characteristics.