206 results about "Frequency coupling" patented technology

A broadband antenna includes a coupling loop and a number of radiation bodies. The coupling loop is electrically coupled to a chip and the chip records several pieces of data. The radiation bodies respectively form a number of resonance loops with the coupling loop for providing a number of resonance frequencies of the broadband antenna. The coupling loop can feed in signals for reading data in the chip according to the resonance frequencies.

A plasma reactor for processing a workpiece includes a reactor chamber and a workpiece support within the chamber, the chamber having a ceiling facing the workpiece support, an inductively coupled plasma source power applicator overlying the ceiling, and an RF power generator coupled to the inductively coupled source power applicator, a capacitively coupled plasma source power applicator comprising a source power electrode at one of: (a) the ceiling (b) the workpiece support, and plural VHF power generators of different fixed frequencies coupled to the capacitively coupled source power applicator, and a controller for independently controlling the power output levels of the plural VHF generators so as to control an effective VHF frequency applied to the source power electrode. In a preferred embodiment, the reactor further includes a plasma bias power applicator including a bias power electrode in the workpiece support and one or more RF bias power generators of different frequencies coupled to the plasma bias power applicator.

A plasma reactor includes an electrostatic chuck in the chamber for supporting the workpiece, a ceiling electrode facing the electrostatic chuck and an ESC electrode in the electrostatic chuck with an electrostatic clamping voltage supply coupled to the ESC electrode. The reactor further includes at least a first RF bias source of an LF or HF frequency coupled to the pedestal electrode, and first and second VHF power sources of different frequencies coupled to the same or to different ones of the electrodes. The first and second VHF power sources are of sufficiently high and sufficiently low frequencies, respectively, to produce center-high and center-low plasma distribution non-uniformities, respectively, in the chamber.

The invention discloses a displacement buffer which can reduce a frequency coupling effect and a displacement buffer unit; wherein every level of the displacement buffer unit comprises at least a lifting driving module, a lifting module, at least a pull-down module and a pull down driving module; wherein, before a first frequency signal waveform or a second frequency signal waveform used by the lifting module forms an ascending edge, the pull-down driving module opens the conduction of the pull-down module for a particular period according to a first periodic signal; and/or before the first frequency signal waveform or the second frequency signal waveform used by the lifting module forms an descending edge, the pull-down driving module closes the conduction of the pull-down module for a particular period according to a second periodic signal; therefore, when the coupling effect of the frequency signal appears at that time, the pull-down module has enough ability to resist so as to improve the output waveform of the displacement buffer unit.

A method of processing a workpiece in a plasma reactor chamber includes coupling RF power via an electrode to plasma in the chamber, the RF power being of a variable frequency in a frequency range that includes a fundamental frequency f. The method also includes coupling the electrode to a resonator having a resonant VHF frequency F which is a harmonic of the fundamental frequency f, so as to produce VHF power at the harmonic. The method controls the ratio of power near the fundamental f to power at harmonic F, by controlling the proportion of power from the generator that is up-converted from f to F, so as to control plasma ion density distribution.

The invention relates to a frequency variable coupling feeding device used in boardband microstrip antenna which includes coplanar waveguide and coupling slit thereon, and a varicap device whose two pins are fixed to two sides of the center of the coupling slit of the coplanar waveguide. Feeding manner is changed by regulating the varicap device, and the provided device can switch frequency resonant points of the antenna in a very wide band thereby realizing frequency conversion when feeding for the antenna; in the state of fixed antenna dimension and fixed shape of the coupling slit, the invention can improve the antenna performance such as better bandwidth and plus only by regulating the varicap device. The invention provided device is fit for the broadband or multi-frequency wireless communication field.

The invention discloses a terahertz wave detector. A gallium nitride high electron mobility transistor is used as a base structure of the terahertz wave detector. The terahertz wave detector comprises a transistor, a source-drain contact testing electrode and lead part and a terahertz wave coupling antenna; the terahertz wave coupling antenna is the special frequency coupling antenna and is used as a contact electrode to be connected with a nano-structure grid electrode of the transistor; the terahertz wave coupling antenna is positioned at two sides of a source electrode and a drain electrode of the transistor, and contact electrodes of the source electrode and the drain electrode are introduced from two antenna sections; the nano-structure grid electrode of the transistor is connected only with one side of a double-slit opening of the terahertz wave coupling antenna; the source electrode and the drain electrode of the transistor are asymmetrically arranged relative to the terahertz wave coupling antenna. According to the terahertz wave detector, the impedance of a metal electrode of the detector antenna to incident terahertz wave is in match with the input impedance of the grid electrode of the transistor, and therefore, the terahertz wave can be efficiently detected, and the detection sensitivity is high.

Disclosed is a loudspeaker assembly incorporating innovations resulting in an enclosure of very small volume to which is integrated a large area, shallow and lightweight acoustic diaphragm assembly capable of a natural resonant frequency of a few Hertz. This is achieved by incorporating a vacuum chamber in conjunction with a chamber containing compressed gas or vapor that acts against a movable pressure boundary of changeable area being mechanically coupled with the acoustic radiating diaphragm. In an alternative operating mode, the apparatus also serves as a passive low frequency acoustic attenuator.

The invention discloses a method for testing the dynamic characteristics of a lubricating film of a sliding bearing. The method comprises the following steps of: (1) assembling a test platform and a signal acquisition system, adjusting the rotating speed of a main shaft and the temperature and the flow rate of a lubricant, supplying a lubricating medium and starting a drive motor and a signal acquisition instrument; (2) applying excitation force on the main shaft by an electromagnet loading device of the invention, measuring the excitation force by a pressure sensor, measuring the vibration response of the main shaft in horizontal and vertical directions by electric vortex sensors and acquiring and storing signals; (3) changing the rotating speed of the main shaft, keeping the temperature of the lubricant unchanged, and repeating the steps; (4) changing the temperature of the lubricant, and repeating the steps; (5) carrying out time-frequency domain analysis processing on the acquired signals and recognizing the dynamic characteristic parameters of the lubricating film by using an equation of solving frequency domain response by a least square method of solid and virtual frequency coupling; and (6) fitting and analyzing the eight dynamic characteristics parameters of the lubricating film at different rotating speeds and different lubricating temperatures, namely obtaining the three-dimensional dynamic characteristics of the lubricating film of the sliding bearing at varied speeds and varied temperatures.

The invention relates to an object steering detection device based on vortex light rotation Doppler effect. The device mainly comprises a vortex light preparation part and scattered light signal detection part. The vortex light preparation part mainly comprises an He-Ne laser, a polaroid, a lens group, a spatial light modulator and a plane mirror, and the scattered light signal detection part mainly comprises a combination imaging telescope, a multi-mode optical fiber, a photoelectric detector and a micro oscilloscope. Firstly, a Gaussian beam is generated by a laser, and a spatial light modulator loaded with a specific hologram is irradiated and loaded after being collimated to prepare vortex light; secondly, the vortex light transmission rotating speed is omega d, and then is irradiatedon a rotating object, and after the object is scattered, scattered light is collected through the convex lens group, beat-frequency coupling is realized under the action of the beam splitter prism andthe original vortex light; and finally, the intensity change of the coupling light beam is detected by utilizing the photoelectric detection and transmitting the signal to the oscilloscope, Fourier transformation is carried out on the oscilloscope, and object steering can be judged according to the frequency spectrum information. The device is simple in structure and can still work effectively under various extreme conditions.

The invention relates to a multi-frequency coupled vibration energy capturer comprising multiple piezoelectric cantilever beams (1), a base frame (3), and an electric control plate (4). The piezoelectric cantilever beams (1) are installed on the base frame (3). Permanent magnets (2) are disposed on the piezoelectric cantilever beams (1). The multiple piezoelectric cantilever beams (1) have same length and different thicknesses. The permanent magnets (2) are arranged on the same positions of the multiple piezoelectric cantilever beams (1). The multiple piezoelectric cantilever beams (1) are connected with the electric control plate (4) through a line. Each piezoelectric cantilever beam (1) is composed of a metallic sheet (5), a piezoelectric patch (6), and a silver electrode surface (7). Compared with a product in the prior art, the multi-frequency coupled vibration energy capturer is novel and simple in structure and uses the magnetic coupling of the multiple piezoelectric cantilever beams with different inherent frequencies. When being seriously deformed, any piezoelectric cantilever beam forces other piezoelectric cantilever beams to deform. Thus, more energy can be captured in a wider frequency domain and high energy capture efficiency is achieved.

The invention discloses a grid-connected inverter frequency coupling impedance characteristic extraction method based on multi-sine-wave signal injection. The method comprises the steps: adopting an impedance measuring device based on a model predictive control method to realize the low-impedance characteristic in a broadband range; decomposing the multi-input and multi-output frequency coupling impedance characteristics of the grid-connected inverter into four single-input and single-output subsystems and performing independent measurement; measuring the broadband frequency coupling impedancecharacteristics of the grid-connected inverter through one-time signal injection, so enough measurement precision and rapidity are ensured. Compared with an existing frequency coupling impedance characteristic extraction method, the frequency coupling impedance characteristic extraction method has the advantages that the impedance characteristic extraction efficiency is remarkably improved whilethe measurement precision is guaranteed, and faster and more efficient frequency coupling impedance characteristic extraction can be achieved.

Disclosed are a closed loop automatic level control method and a device used for the TDD mode communication system. The method is that during the coupling process of the input radio-frequency signal which is processed with radio-frequency coupling, radio-frequency attenuation and power amplification firstly, the input signal is detected in advance to extract the signal envelope for the voltage comparator of a singlechip and the signal envelop is compared with the preset voltage value to obtain the synchronous signal time sequence; then the level of the output signal is detected and is transmitted to the A/D converter of the singlechip; the A/D converter of the singlechip samples and outputs the detection signal; the singlechip judges the signal level; then the radio-frequency attenuator in the link circuit is controlled by the singlechip to realize the stable closed loop automatic level control. The device comprises a serial connection of a radio-frequency coupler (7), a radio-frequency switch (1), a radio-frequency attenuator (2), a drive amplifier (3), a power amplifier (4) and a radio-frequency coupler (8); the control end of the radio-frequency attenuator (2) is connected with a singlechip (9) in which a voltage comparator and an A/D converter are imbedded; the output ends of the radio-frequency couplers (7, 8) are respectively connected with radio detectors (5, 6); the radio detector (5) is connected with the input end of the voltage comparator of the singlechip; the outputted signal of the radio detector (6) is connected with the input end of the A/D converter of the singlechip; the output end of the singlechip (9) is connected with the control end of the radio-frequency switch (1).

The invention discloses an electrically adjusting common mode rejection filter based on selective frequency coupling. The electrically adjusting common mode rejection filter based on selective frequency coupling comprises an upper-layer microstrip structure, loading capacitors, loading variable capacitance diodes, a dielectric substrate and a bottom-layer metal ground plate, wherein the upper-layer microstrip structure is attached to the upper surface of the dielectric substrate, and the lower surface of the dielectric substrate is provided with the bottom-layer metal ground plate; the upper microstrip structure is composed of four half-wavelength resonators, four feeder lines and four ports; both ends of every feeder line form symmetric coupling with both ends of the corresponding half-wavelength resonator; every port is formed in the middle of every feeder line; the loading variable capacitance diodes are arranged at the open ends of the half-wavelength resonators for adjusting the central frequency; the loading capacitors are arranged at the tail ends of the feeder lines and the connecting positions among the feeder lines for controlling external quality factors.

The invention discloses a frequency coupling modeling method for a single-phase LCL-type grid-connected inverter considering a phase-locked loop. A frequency domain expression of an inverter modulation signal considering the output phase angle deviation of the phase-locked loop is obtained through a harmonic linearization method; and then a frequency coupling impedance model of the single-phase grid-connected inverter is established according to a main circuit topology and the modulation signal frequency domain expression, and the problem of accurate modeling of the impedance of the single-phase grid-connected inverter is solved; based on the model, system stability and the influence of all system parameters on the frequency coupling degree can be analyzed; and from the established model,it can be seen that the frequency coupling phenomenon mainly occurs at the low frequency, and the coupling current component generated at the high frequency can be almost negligible. According to thefrequency coupling modeling method, the theoretical basis is provided for stability analysis of a new energy grid-connected system.

The doubly-fed variable-speed pumped storage unit is a novel hydroelectric system, and due to the fact that the rotating speed is continuously adjustable under a water pumping working condition, on the premise that a static lift is guaranteed, the input power adjusting range of the unit is widened through variable-speed operation. For the potential that an excavator unit participates in power grid frequency modulation, the invention relates to an active power-frequency coupling control method based on an electromechanical transient model of a doubly-fed variable-speed pumped storage unit under a water pumping working condition. The method comprises the following steps of: firstly, establishing a simplified electromechanical transient model of a variable-speed unit under a water pumping working condition; according to the model, on the basis of the operation characteristics of a pump turbine with the reversible water pumping working condition, considering the dynamic characteristics of fluid in an overflowing pipeline, and considering the additional friction effect of guide vanes; revealing the essential reason of the frequency modulation capability of the water pumping working condition unit from the angle of hydraulic power; clarifying a mechanism of improving power grid frequency characteristics by a water pumping working condition unit, and giving recommendation range of controller parameters; and finally, through simulation and experiment results, verifying the capability of improving the frequency characteristic of the power grid of the water pumping working condition unit.

The invention discloses an admittance model and impedance model acquisition method and device of a voltage source converter. The method comprises the steps that multiple converter parameters are acquired; multiple converter control parameters are acquired; a grid-connected system is run, and when the grid-connected system is in a steady state, multiple steady state values of the grid-connected system are collected; based on the multiple converter parameters, the multiple converter control parameters and the multiple steady state values, an admittance model transfer function is obtained, and through the admittance model transfer function, a frequency coupling admittance model and impedance model of the converter when the frequency of a small disturbance signal is fs are obtained. By means of the method, the coupling relationship between sub-synchronization and super synchronization can be considered, the influence of outer loop control is also considered, and the frequency coupling admittance model and impedance model of the converter are obtained based on the obtained small disturbance signal, so that the stability of a power system is accurately analyzed.