33results about How to "Realize continuous scanning" patented technology

The invention discloses a liquid crystal light beam deflection and scanning device. The device comprises a wedged liquid crystal box, a liquid crystal polymer polarization grating and adjustable liquid crystal half-wavelength plate combination and a quarter-wave plate, wherein a liquid crystal layer is arranged between two oppositely arranged base plates of the wedged liquid crystal box; light-alignment films with molecules pointing to the vector direction and uniformly distributed are arranged on the sides, adjacent to the liquid crystal layer, of the two base plates, and molecules on the liquid crystal layer are uniformly distributed and in parallel with the first base plate; the liquid crystal polymer polarization grating and adjustable liquid crystal half-wavelength plate combination is provided with two parallel base plates, a liquid crystal layer and liquid crystal polymers, the light-alignment films with molecules pointing to the vector direction and uniformly distributed are arranged on the sides, adjacent to the liquid crystal layer, of the two base plates, and light-alignment films with molecules pointing to the vector direction and gradually changing periodically are arranged on the sides, adjacent to the liquid crystal polymer layer of the two base plates; the quarter-wave plate is used for converting linearly polarized light into circularly polarized light. Continuous light beam deflection and scanning in a large angle range can be realized by means of the liquid crystal light beam deflection and scanning device.

The invention discloses a synchronous measurement method of a three-dimensional real-time attitude angle of a low-speed wind tunnel test model. The method applies an Optotrak optical displacement measurement system to enable the wind tunnel test model to be a rigid body and measure a rigid body euler angle, the attitude angle of the model is solved through the rigid body euler angle, and synchronous measurement of the attitude angle of the model and other signals (such as a balance signal) of wind tunnel tests is achieved. The measurement method is verified by multiple wind tunnel tests, and the accuracy, real-timeliness and synchronism meet the test requirements.

The invention discloses a compact feed network type spoof surface plasmon polariton (SSPP) panel antenna array, and relates to the technical field of antennas. The panel antenna array is composed of an SSPP power division network and a transmission type phase gradient metasurface. The SSPP power distribution network is a 1/2 power division network, so that the generated SSPP is transmitted according to the design direction, and the SSPP energy is transmitted according to the designed proportion. By virtue of the SSPP power division network for feeding and by virtue of the transmission type phase gradient metasurface for decoupling, the two-path compact SSPP panel antenna array is realized. Simulation and experimental verification show that the SSPP panel antenna array is 16.9dB in averagegain, 80% or above in antenna total efficiency and 93.5% in total efficiency within the frequency band of 6.7-14GHz.

The invention discloses a dual-beam frequency scanning leaky-wave antenna. The dual-beam frequency scanning leaky-wave antenna is composed of a dielectric substrate, a top metal panel, a bottom metalpanel and a metal tube, a half-mode substrate integrated waveguide structure is adopted, based on the periodic sine impedance modulation principle, a double-period sine impedance modulation groove isformed in the top metal panel to serve as a radiation unit, and due to the fact that the top metal panel is formed by superposing sine impedances of two kinds of single beams, beams in two radiation directions can be generated; a periodically changing groove is also arranged on the bottom metal panel as a radiation unit, so that the radiation efficiency of the antenna can be improved, the stop band effect of the periodic leaky-wave antenna can be inhibited, and compared with the traditional double-beam frequency scanning antenna, the dual-beam frequency scanning leaky-wave antenna has the characteristics of simple structure, narrow bandwidth, large scanning angle and the like.

The invention discloses a planar phased array-based two-dimensional beam scanning method. According to the prior art, when a liquid crystal spatial light modulator is adopted to deflect a two-dimensional beam, only a limited deflection angle can be realized; a one-dimensional phase modulation diagram needs to be rotated; an entire scanning range is in sparse and uneven concentric circle distribution; and as a scanning angle increases, diffraction efficiency is seriously degraded, and as a result, problems such as a problem of failure to meet the practical requirements of capture, tracking andaiming (ATP) in spatial optical communication which require beam continuous scanning can be solved. With the method adopted, the problems of scanning range discreteness and uneven distribution can besolved, diffraction efficiency can be improved, and the requirements of practical application can be better met.

The invention provides a laser scanning electrode structure. The laser scanning electrode structure comprises a liquid crystal layer, an electrode driving layer is arranged above the liquid crystal layer, an electrode driving device is arranged on the electrode driving layer, the electrode driving device comprises a laser angle control part, the laser angle control part comprises an incident edgeand an emergent edge, the incident edge and the emergent edge are straight edges and are intersected with each other or extending lines of the incident edge and the emergent edge are intersected witheach other, and the electrode driving device is electrically connected with the liquid crystal layer. Through the arrangement of the liquid crystal layer and the electrode driving device, the refractive index of the liquid crystal layer can be changed through electrode control, and therefore, the change of the laser propagation direction is achieved. Because of the fact that a discrete electrode structure is adopted, when high sampling frequency and high-precision regulation and control are achieved, the requirement for later-period electric control signals is greatly lowered, and accurate control over the scanning angle by the voltage is achieved.

The present invention discloses a linear frequency modulation optical grating 5bit optical fiber delay network device and a design method thereof. The device comprises an optical input module, a linear frequency modulation optical grating and an N-path optical switch, N is a positive integer, wherein the optical input module is configured to allow radio-frequency signals to be delayed to be carried on optical signals, the linear frequency modulation optical grating is configured to perform first-order delay for the radio-frequency signals on the optical signals, and each path of the N-path optical switch is provided with single mode fibers with different lengths configured to divide the radio-frequency signals after first-order delay into N paths and perform secondary delay of different time. The linear frequency modulation optical grating 5bit optical fiber delay network device and the design method thereof apply frequency modulation optical grating to greatly reduce the usage of theoptical fiber, only need to design the model of the optical grating according to actual demands to achieve continuous regulation of an optically controlling phased array radar waveform, and are largein delay range, high in precision, simple in structure and flexible in design.

The invention discloses an integrated lens antenna, which comprises a first dielectric lens, a microstrip radiation unit and a base, the microstrip radiation unit is arranged at one side of the base and located in the base; the first dielectric lens is of a rotational symmetry structure, and a main body of the first dielectric lens is hemispherical; the plane side of the first dielectric lens is arranged at the other side, far away from the micro-strip radiation unit, of the base, and is spaced from the micro-strip radiation unit; therefore, a certain height difference exists between the hemispherical dielectric lens and the microstrip radiation unit, the influence of the dielectric lens on the impedance matching performance of the microstrip radiation unit is reduced, and the hemispherical rotational symmetric structure can convert the radiation beam of the microstrip radiation unit into a parallel beam; therefore, the radiation beam can realize continuous scanning in the two-dimensional direction and can be converged, the gain of the lens antenna is improved, and the continuous scanning in the two-dimensional direction of the antenna is realized.

The invention belongs to the field of power system simulation, and in particular relates to a three-dimensional scanning method for an electrical complex torque coefficient based on PSCAD (Power System Computer Aided Design).The method comprises the following steps: loading a three-dimensional scanning module of the electrical complex torque coefficient on electromagnetic transient software, calculating a series compensation capacitance value according to a series compensation degree, and then generating a disturbance and applying to a rotor mechanical torque; when a system once again enters into a steady state, extracting a generator electromagnetic torque signal and a rotor angular velocity response variable, and calculating the electrical complex torque coefficient; judging whether a scanning frequency exceeds a cut-off frequency or not, if not, increasing a frequency scanning step length, if yes, stopping calculation; judging whether a scanning compensation degree exceeds a cut-off compensation degree or not, if not, increasing a compensation degree scanning step length, if yes, completing three-dimensional scanning. According to the three-dimensional scanning method disclosed by the invention, the frequency and the compensation degree are continuously scanned to obtain a three-dimensional curve of the frequency, the compensation degree and the complex torque coefficient, the simulation method is fast, the cost is low, and the three-dimensional scanning method is not affected by multiple FACTS (Flexible Ac Transmission System) devices in the system.

The invention discloses a separated lens antenna and communication equipment. One side of a dielectric lens is arranged to be a plane, the other side of the dielectric lens is arranged to be a convex face with the height changing in the single-dimension direction, and the dielectric lens is arranged at the position where the distance between the dielectric lens and a micro-strip radiation unit equals the focal length of the dielectric lens through a lens support, so that electromagnetic waves can be fully diffused when propagating between the micro-strip radiation unit and the lens, and when propagating to the dielectric lens, the electromagnetic waves can be radiated to the outer side of the dielectric lens only after passing through the convex surface of which the height changes along the single-dimensional direction; therefore, the phase change of the electromagnetic wave is changed only in a single-dimensional direction, and the phase change of the electromagnetic wave in other dimensional directions is not changed, so that the radiation gain of the antenna is enhanced, and the beam direction of the electromagnetic wave radiated by the microstrip radiation unit is ensured to be consistent with the beam direction of the electromagnetic wave emitted after passing through the dielectric lens. Therefore, continuous scanning of the antenna in the one-dimensional direction is realized.

The invention discloses a laser radar and a two-dimensional scanning method of the laser radar. The laser radar comprises at least one tunable laser and a scanning device, and the tunable laser is used for outputting a laser beam with continuously variable wavelength; and the scanning device comprises at least one scanning mirror and a driving device, and a diffraction grating is arranged on the scanning mirror and can have different diffraction angles for light of different wave bands. Continuous scanning in the horizontal one-dimensional direction is achieved through vibration or rotation ofthe scanning mirror, laser beams with different emergent angles are obtained through grating diffraction by changing the wavelength output by the tunable laser, and scanning in the vertical two-dimensional direction is achieved. According to the invention, the density of the laser point cloud is increased, the resolution of the spatial orientation is improved, and the device is simple in structure and easy to realize.

The invention provides a wheel type probe fixing system for vertical flaw scanning. The system comprises a fixing frame, a pair of walking wheels and a water wheel seat; at least three probes are arranged on the water wheel seat; and the probes comprise at least one transmitting probe or receiving probe; ultrasonic waves emitted by the transmitting probe can be received by a receiving probe after being subjected to twice mirror reflection of a vertical flaw in a track and the bottom surface of the track; the multiple probes on a probe support can be matched to scan the vertical flaw at multiple heights in a flaw detection area. According to the wheel type probe fixing system for vertical flaw scanning, the walking wheels can be automatically attached to the track under the action of side baffles and reset springs, and it is further ensured that the probes are kept in the center of the track under the action of a motor; and through cooperation of the multiple probes, continuous scanning of the whole height range in the flaw detection area is achieved, and use is convenient.