182 results about "Resonance oscillation" patented technology

Microwave generating and detection portions of a electronic circuit is improved in efficiency and reduced in size. A microwave generating element A comprises a lower electrode 1, a layer 3 formed on the lower electrode 1 in an island shape, forming a magnetoresistance element, an insulator 7 formed on the lower electrode 1 in such a manner as to surround the layer 3 forming the magnetoresistance element, and an upper electrode 5 formed on the insulator 7 and the layer 3 forming the magnetoresistance element. The layer 3 forming the magnetoresistance element includes, in order from the side of the lower electrode 1, a magnetization fixed layer 3a, an intermediate layer 3b, and a magnetization free layer 3c. The magnetization free layer 3c, which is required to produce resonance oscillation based on a current, preferably is dimensioned to be equal to or smaller than 200 nm square in a cross-sectional area and on the order of 1 to 5 nm in film thickness, for example. The magnetization fixed layer 3a, when made of a single material, is required to have a thickness 10 times or more of the thickness of the magnetization free layer 3c. The magnetization fixed layer 3a may be comprised of a magnetic metal multilayer film that utilizes antiferromagnetic coupling.

A voltage controlled LC resonance oscillation circuit has a plurality of capacitive elements connected to an output node. These capacitive elements are applied with voltages at opposing terminals for selecting an oscillating frequency band, so that the oscillating frequency band can be changed step by step in accordance with the selection voltage. The capacitive elements include at least one variable capacitive element such as a MOS capacitor, the capacitance of which is varied in accordance with a voltage applied thereto. The MOS capacitor is similar in structure to a MOS transistor. The variable capacitive element can be supplied at a terminal opposite to the output node with a voltage from a variable voltage source, for example, in place of the selection voltage. The voltage controlled LC resonance oscillation circuit can measure the output amplitude and oscillating frequency without affecting the characteristics thereof, and reduce the parasitic capacitance.

The invention discloses an adjustable multi-band antenna system which is suitable for mobile terminals with metal frame structures. The adjustable multi-band antenna system comprises a metal frame, a PCB and an antenna part. According to the adjustable multi-band antenna system, the metal frame is designed as one part of an aerial radiation body, a clearance is formed in the metal frame, a low-frequency branch is arranged to be combined with the metal frame to generate low-frequency resonance oscillation, and a high-frequency branch is arranged for generating high-frequency resonance oscillation. An IFA mode is adopted by the adjustable multi-band antenna system, the metal frame is used for achieving the ground point supporting section of the IFA antenna, and a low-frequency coupling part and a high-frequency coupling part can be added additionally according to needs. The adjustable multi-band antenna system has the advantages that the clearance of the metal frame is formed in the bottom, the collision on the clearance can be avoided to the greatest extent in an actual using process of a user, and the phenomenon that when the antenna is held by the hand performance is poor is avoided. The working frequency band of the adjustable multi-band antenna system is 704Mhz to 960Mhz and 1710Mhz to 2700Mhz, and multiple frequency broadband can be achieved. Compared with a traditional general antenna, the adjustable multi-band antenna system has the advantages of being multiple in frequency band and wide in bandwidth.

The invention discloses a hydraulic pulse drilling device with cavitation jet, which comprises a columnar body, wherein a fluid inlet section is provided at one end of the body, a fluid outlet section is provided at the other end of the body, and a fluid diversion portion for deviating the flow direction of the fluid, a pulse generator allowing the continuous fluid to generate pulse and a self-oscillation portion for allowing the fluid with pulse to generate resonance oscillation are sequentially provided between the fluid inlet section and fluid outlet section. The invention also discloses a self-resonating cavitation jet nozzle for drilling head, which improves the rock breaking effect of drilling head and rock cleaning effect at well bottom. The invention also discloses a hydraulic pulse drilling method with cavitation jet, which comprises during drilling work, converting continuous and stable fluid flow for impacting well bottom to pulse resonance flowing fluid; and injecting the pulse resonance flowing fluid into relatively static fluid to generate cavitation phenomena. The impact of well bottom with oscillating pressure reduces clip hold down effect, improves the rock cleaning and rock breaking capacity by jetting, and saves drilling cost.

A magnetic resonance antenna has longitudinal antenna rods in a birdcage structure, and antenna ferrules connecting the longitudinal antenna rods at their ends in terms of radio-frequency. The magnetic resonance antenna has a number of radio-frequency switching elements that interrupt, in terms of radio-frequency, at least one part of the longitudinal antenna rod to detune the eigen-resonance frequency of the antenna with respect to an operating magnetic resonance frequency. For this purpose, the magnetic resonance antenna is provided with two switching lines, directed to the radio-frequency switching elements from outside of the birdcage structure, the switching lines having a ring line connected thereto running annularly on or in the birdcage structure and transverse to the longitudinal antenna rods.

The invention aims to realize that a control mode of primary side feedback is added into an asymmetric half bridge type flyback converter in a non-complementary DCM mode. For the asymmetric half bridge type flyback converter working in the non-complementary DCM mode, primary side inductance is released and is not clamped by an output end at the moment of finishing primary side excitation energy resetting. At the time, the primary side inductance, resonant capacitance, leakage inductance, and parasitic capacitance between the drain and the source of an MOS transistor start resonance oscillation; and at the moment of oscillation starting, a voltage between the drain and the source of the MOS transistor forms an "inflection point", voltages on two ends of the primary side inductance reflect voltage changes of the output end, voltages ontwo ends of an auxiliary winding have similar changes, an oscillation starting direction is just opposite to the direction of the voltages on the two ends of the primary side inductance due to a dotted terminal winding relationship, and if the inflection point is detected through the auxiliary winding and inflection point information is transmitted to a controller, the detection and control of an output voltage can be realized. Compared with the prior art, relatively high output voltage precision, linear adjustment rate and load adjustment rate of the converter can be ensured; and meanwhile, zero voltage switching (ZVS) of a primary side switch tube can be realized, the working frequency of the converter can be increased, the efficiency of the converter can be improved, and the volume of a complete machine is reduced.

The invention provides a nested annular MEMS oscillation gyro with period distribution type concentrated mass blocks. The gyro comprises a nested annular harmonic oscillator with the period distribution type concentrated mass blocks, and an electrode which is arranged inside / outside the nested annular harmonic oscillator; the nested annular harmonic oscillator comprises a nested annular flexible frame, the mass blocks arranged on the nested annular flexible frame, and anchors for fixing the oscillator; the whole harmonic oscillator is fixedly anchored with a base by the anchor on the center of the harmonic oscillator; the nested annular flexible frame comprises nested rings and spoke-shaped supporting beams; the mass blocks can be additionally arranged on the nested annular flexible frame in a plurality of kinds of manners; and the electrode can be arranged inside / outside the harmonic oscillator, or the electrodes are arranged inside and outside the harmonic oscillator. The gyro has the relatively high thermo-elastic property Q value, relatively large resonance oscillation mass, and relatively large driving amplitude; and as the design of the internal electrode is adopted or the design of the internal and external electrodes is adopted, the gyro also has the advantages that the capacitance detection area is large, the number of detection and control electrodes is large and the like.

The invention relates to a method for restraining resonance mechanism low-frequency oscillation of a power system. The method is applied to a unified power flow controller in the system and includes the steps that at the measurement step, signal collection is performed on the system, and a bus power signal P in signals is sequentially processed in the blocking step, the proportion resonance control step, the phase compensation step and the amplitude limiting step, so that an output control signal Up is obtained; the control signal and a reference value corresponding to the unified power flow controller are superposed, so that a corresponding adjusting signal is obtained; difference operation is performed on the signal P and the adjusting signal, difference operation is performed on the multiple obtained signals at the measurement step and corresponding reference values, all difference value signals are sequentially processed at the first-order inertia step and the proportional integral step, so that current and voltage corresponding to an output q axis and an output P axis are obtained and then injected into the system, and the damp for restraining the resonance mechanism low-frequency oscillation in the system is increased. The method has the advantages of being capable of effectively decreasing the resonance oscillation magnitude value and restraining the resonance mechanism low-frequency oscillation.

The invention discloses a mobile self-adaption energy and information synchronization wireless transmission method which comprises the following steps: Step 1, an embedded MCU generates a combination frequency signal; Step 2, the combination frequency signal is coupled to a wireless strong coupling type bilateral matching receiving coil; Step 3, an optimal frequency estimation circuit estimates a resonance oscillation frequency point; when the frequency of a frequency synthesizer is stabilized, the Step 4 is carried out; Step 4, the embedded MCU generates an information sequence, and a frequency-selecting switch controls signal output; Step 5, according to the amplitude of fluctuation of a DC signal, the situation that whether a device enters a restarting mode or not is determined; Step 6, when the amplitude of fluctuation of the DC signal is smaller than the reference level offset, the device enters the restarting mode. The invention further discloses a device for realizing the mobile self-adaption energy and information synchronization wireless transmission method. The device comprises an energy and information wireless launching unit and an energy and information wireless receiving and recovery unit connected with each other and has the advantages of high efficiency and reliability.

An apparatus enhances the condensation and boiling of a fluid in heat exchange machines, by directly applying time-periodic acoustic waves with a resonance oscillation frequency to liquid drops and / or bubbles formed on a solid surface, when the fluid is in the process of condensation or boiling, thereby effectively removing them therefrom. The apparatus comprises a signal generator for generating a driving signal based on a resonant oscillation frequency of at least one of the liquid drops and the bubbles; and a vibrator, in response to the driving signal, for providing an acoustic pressure wave to said at least one of the liquid drops and the bubbles, to thereby detach them from the solid surface.

The invention belongs to the field of electrical technologies and relates to an isolated type DC / DC boost converter provided with a pull-up active clamping branch and a control method thereof. On the basis of the single-end flyback-type circuit topology, the primary side of a transformer is connected in parallel with a resonant capacitor and a pull-up active clamping branch. The secondary side of the transformer is in cascade connection with a high-frequency voltage doubling circuit. The resonance oscillation occurs between the resonant capacitor and the primary side of the transformer, wherein the resonant capacitor and the primary side of the transformer are connected in parallel. In this way, the bidirectional excitation of an original circuit is enabled and the utilization rate of a magnetic core is improved. Meanwhile, the output-to-input voltage gain of the isolated type DC / DC boost converter is improved. The auxiliary switch tube and the main switch tube of the active clamping branch are the same in switching period, while the auxiliary switch tube is only turned on for a short period of time during each switching period. Therefore, the conduction loss is reduced. The soft switching of the main switch tube and the soft switching of the auxiliary switch tube are both enabled, so that the direct connection problem is avoided. Through arranging the high-frequency voltage doubling circuit in cascade connection with the secondary side of the transformer, an asymmetrical voltage outputted by the secondary-side winding of the transformer is effectively utilized. Therefore, the overall efficiency of the converter is further improved.

The invention discloses a high sensitive biochemical sensor based on a resonance oscillation type micro cantilever beam structure. The biochemical sensor comprises a resonance oscillation chamber, a cantilever beam and a Whist bridge type detection circuit, wherein a micro column structure (3), a liquid storage tank (4) and a liquid leakage hole (5) through which biochemical solution flows are etched at the free end of the cantilever beam; the support end of the cantilever beam is connected with the Whist bridge type detection circuit; the Whist bridge type detection circuit is composed four U-shaped piezoresistance bars (1), three input electrodes (8, 9, 10) and two output electrodes (7, 11); and the four piezoresistance bars (1) are connected with the input electrodes (8, 9, 10) and the output electrodes (7, 11) through a signal transmission line (2). With the adoption of the biochemical sensor, micro biochemical molecules can be sensed with a high sensitivity by detecting the frequency change after an object to be tested is absorbed; biochemical molecules with micromass can be detected; and the biochemical sensor can be widely used in engineering fields such as medicine and chemistry.

A filling level sensor comprises a tunable electrical resonant circuit, a mechanical oscillator that can be excited to resonance oscillation by the resonant circuit, and a control circuit for tuning the resonant circuit to a resonance frequency of the mechanical oscillator. A device for comparing the amplitude of the mechanical oscillator with a minimum value ascertains a malfunction of the mechanical oscillator if its amplitude falls below the minimum value.

The invention discloses a bidirectional-resonance bridge type modular multi-level switched capacitor DC-AC converter which sufficiently uses stray inductance of circuits to serve as resonance oscillation and can achieve level extension easily through an extension switched capacitor module. Bidirectional energy flow between the high voltage side and the lower voltage side and regulation of output voltage are achieved through phase-shifting control of a switch tube. In the boosting state, the bidirectional-resonance bridge type modular multi-level switched capacitor DC-AC converter can output input voltage of 2-4 times; in the depressurization state, the bidirectional-resonance bridge type modular multi-level switched capacitor DC-AC converter can output input voltage of 0-0.5 time. The bidirectional-resonance bridge type modular multi-level switched capacitor DC-AC converter is simple in control, solves the problems that output voltage of the traditional switched capacitor is difficult to regulate, bidirectional energy flow is hard to control and peak currents of the working circuits are large, and improves efficiency and power density of the converter; is mainly applied to occasions where bidirectional energy flow, high efficiency and large power are required, such as micro-grid and electromobile motor drive.

The invention discloses an antenna device. When the antenna device is arranged in an electronic device comprising a circuit board, the antenna device is used for receiving and transmitting wireless signals of the electronic device. The antenna device comprises a radiating body and an electric array susceptance component, wherein the radiating body comprises a first end which is grounded due to arrangement on the circuit board, the electric array susceptance component has a second end and a third end, the second end is connected with the radiating body, the third end is grounded due to arrangement on the circuit board, the electric array susceptance component has K kinds of different impedance values, and K is an integer greater than or equal to 2; when in a powered-on state, the radiating body can generate K kinds of resonance oscillation signals different in frequency range based on the K kinds of different impedance values.

A quartz girder resonant mode micro-pressure sensor chip with a silicon substrate single island structure comprises a quartz girder which is bonded on the front of the silicon substrate through low stress adhesive glue. Four opposite angles of the quartz girder are directed at four alignment markers on the front of the silicon substrate. The back of the silicon substrate is connected with a glass substrate in a sealing mode. The front of the glass substrate corrodes a groove. A pressure hole is formed at the center of the groove. The pressure hole is communicated with the atmosphere to form a gauge pressure sensor, or is communicated with the other tested atmosphere to form a differential pressure type sensor. The back of the silicon substrate corrodes the groove to form a silicon island. The quartz girder is driven to self-oscillate with an inverse piezoelectric effect of the quartz and when vibration frequency is equal to the inherent frequency of the quartz girder, resonance oscillation occurs. Resonant frequency is tested under a closed-loop feedback control system. Variable quantity of the resonant frequency represents the size of air pressure to be tested, and therefore the measurement of the outside air to be measured can be realized. The quartz girder resonant mode micro-pressure sensor chip with the silicon substrate single island structure has the advantages of being high in sensitivity, high in accuracy and high in resolution ratio.

The invention discloses a low frequency oscillation distinguishing method based on response ingredient and oscillation characteristic identification. The low frequency oscillation distinguishing method mainly comprises the following steps: selecting to-be-analyzed oscillation data; identifying response ingredients and oscillation characteristics; first distinguishing negative damping oscillation, ending if the oscillation is negative damping oscillation, or else performing distinguishing of resonance oscillation; if the oscillation is distinguished to be resonance oscillation in the distinguishing process of the resonance oscillation, and transferring to distinguishing of positive damping resonance and zero damping resonance; otherwise, transferring to distinguishing of positive damping free oscillation, performing distinguishing of zero damping equiamplitude free oscillation if the oscillation is not positive damping free oscillation, performing distinguishing of zero damping beat frequency oscillation if the oscillation is not distinguished to be zero damping equiamplitude free oscillation, performing distinguishing of positive damping beat frequency oscillation if the oscillation is not distinguished to be zero damping beat frequency oscillation, and ending. The low frequency oscillation distinguishing method has the advantages of being simple and clear in principle, distinguishing finely and being complete in criterion.

Capacitive discharge system for ignitors of internal combustion engines with one ignition coil (T) per ignitor with one or more capacitors (6) and shunt switch means (5) associated with each such coil, together forming a coil primary ignition circuit of Type II topology and resonance oscillation capability, each switch means being a series combination of shunt diode (D) means and switch (SD) across the coils primary winding, with a voltage drop element (Vdb) across switch SD, the system constructed to produce capacitive ignition initial spark discharge of duration less than a quarter period of the resonance oscillation of the primary ignition circuit followed by an essentially triangular distribution decaying spark discharge of longer duration than the initial discharge, with switch SD to be turned off near or after spark circuit zero to divert residual primary discharge circuit through the voltage drop element.

The invention provides a turn-on characteristic testing apparatus of a large power semiconductor device. The turn-on characteristic testing apparatus of a large power semiconductor device comprises a constant current source unit, a testing main circuit unit, a heating loop unit and a protective loop unit, wherein the constant current source unit outputs direct current and can charge an adjustable capacitor C; the adjustable capacitor C is charged to reach a testing voltage; in the course of discharging, the adjustable capacitor C generates a testing current with an adjustable electric reactor L in a resonance oscillation way; in such a way, a turn-on test on the large power semiconductor device under various working conditions is realized; the heating loop circuit heats the large power semiconductor device to a testing junction temperature; and the protective loop unit prevents damages to the large power semiconductor device caused by the test. With the adoption of the turn-on characteristic testing apparatus of a large power semiconductor device, the turn-on test can be performed on the tested large power semiconductor device under the various conditions; the device is simple and practical in topological structure and comprehensive in function, and can satisfy the requirements of the turn-on characteristic test on the device under the various conditions; meanwhile, the protective measures for the device and the tested device in the case of faults are fully taken into account; and therefore, the reliability is high.

The invention discloses a synchronized rectifier tube control circuit, comprising: a voltage slope detection circuit, a transformer and synchronized rectifier output stage circuit, a logic circuit and a driving circuit wherein the voltage slope detection circuit, the logic circuit, the driving circuit and the transformer and synchronized rectifier output stage circuit are connected in sequence. According to the invention, through the arrangement of the voltage slope detection circuit to detect the slope for the voltage variation of the synchronized rectifier tube's drain electrode, it is possible to accurately tell the cause of the voltage variation at the drain electrode by the closing of the main power tube at the primary side from the cause of the resonance oscillation by the closing of the synchronized rectifier tube so as to avoid the wrong start of the synchronized rectifier tube due to oscillation and to further realize the right start of the synchronized rectifier tube.

Disclosed is a distributing cable partial discharge test method based on oscillatory wave test. The method includes that a cable partial discharge testing and locating system based on oscillatory wave test is established; by means of the testing system, a cable is charged through a method of voltage increasing to a preset value at a tested cable end, and damped oscillation voltage is generated at the tested cable end through resonance oscillation that occurs by an inductor and a tested cable capacitor in the system; when partial discharge occurs at a position of the tested cable in a distance from a testing end, pulses can spread in two directions along the cable, and the position where the partial discharge occurs can be determined according to time difference that two pulses such as incident wave and radioactive wave reach the testing end. According to the distributing cable partial discharge test method based on oscillatory wave test, oscillatory wave is applied to partial discharge test of the distributing cable, and voltage increasing is performed on the cable through sine oscillatory wave that is generated by resonance oscillation of fixed inductor and the cable. By means of the distributing cable partial discharge test method based on oscillatory wave test, insulating conditions of the cable can be timely known within short time by the system, and thereby, accidents of the cable can be effectively prevented.

An optical scanning device includes an optical scanning element which has a reflection mirror and is configured to perform reciprocating scanning of an optical flux radiated from a light source by resonance oscillations of the reflection mirror; a photo detector which is arranged at a position which a portion of the optical flux scanned by the optical scanning element in a reciprocating manner passes in both outgoing-path scanning and incoming-path scanning, and is configured to output a pulse signal having a predetermined width at a point of time that the scanned optical flux is detected; and the reference signal generator which is configured to detect timing between rising edge timing of one pulse signal and falling edge timing of the other pulse signal out of two pulse signals continuously outputted from the photo detector, and to generate the reference signal based on intermediate timing between the edge timings.

A device for establishing and / or monitoring a predetermined fill level in a container is provided, which also operates stably in liquids with surface waves, which includes: a mechanical oscillatory structure placed at the height of the predetermined fill level, an electromechanical transducer, which in operation excites the oscillatory structure to resonance oscillations, and a receiver- and evaluation-unit, which serves for determining from the resonance oscillation whether the predetermined fill level has been reached, or not, in which a shape of the oscillatory structure is so constructed that the resonance frequency changes only slowly with immersion depth in the case of immersion in the region of the predetermined fill level.

A ring gyroscope which comprises a substantially circular and flexible ring which defines a ring plane, one or more primary piezoelectric split transducers configured to drive the ring into resonance oscillation, four or more mass elements which form a symmetrical mass distribution in relation to both a first and a second transversal symmetry axis and to a first and a second diagonal symmetry axis. The ring gyroscope also comprises a suspension structure configured to support the weight of the ring and the mass elements, wherein the suspension structure comprises N outer suspenders, where N is an integer greater than or equal to two, and each outer suspender extends along a ring tangent from a suspension attachment point on the outer edge of the ring to an anchor point.

The invention belongs to the technical field of electricity, and relates to an isolated DC-DC boost converter with pull-down active clamping branch circuits. On the basis of a single-ended flyback type circuit topology, a resonant capacitor is connected in parallel on the primary side of a transformer, the pull-down active clamping branch circuits are in parallel connection at two ends of a drain source of a main switch tube; a high-frequency voltage doubling circuit is in cascade connection on the secondary side of the transformer; resonance oscillation is carried out on the resonant capacitor and an inductor on the primary side of the transformer which are in parallel connection, so that an original circuit becomes into bidirectional excitation, the utilization rate of a magnetic core is improved, and the voltage gain of isolated converter output for input is improved; the switching period of an auxiliary switch tube is the same as that of a main switch tube in the active clamping branch circuits, but each switching period of the auxiliary switch tube is a small period of time for conduction, the conduction loss is greatly reduced, the main switch tube and the auxiliary switch tube can realize soft switching, and a direct connection problem does not exist; asymmetrical voltage output by a secondary side winding of the transformer is effectively utilized through the high-frequency voltage doubling circuit in cascade connection on the secondary side of the transformer, so that the overall efficiency of the converter is improved.

The invention discloses a micropore atomizer control circuit and a power supply state indication method. The control circuit comprises a microcontroller, a power source and power source signal detection module, a first-level boosting module, a second-level boosting module, an atomization driving indication module and an atomization signal monitoring module. The microcontroller serves as a control core, and the power source and power source signal detection module, the second-level boosting module, the atomization driving indication module and the atomization signal monitoring module are all connected to the microcontroller. By means of the micropore atomizer control circuit and the power supply state indication method, stability and consistency of driving voltage applied in the working process of a micropore atomizer can be guaranteed; the micropore atomizer under different power-supply power sources can have the same driving voltage so that the micropore atomizer in the resonance oscillation state can achieve the consistent atomization effect; and meanwhile, state indication is conducted through atomization pieces instead of LED, and safety and monitorability of the working state of products small in size and low in cost are enhanced.

An optical scanning element performs scanning with light by bringing a mirror portion into a swinging state by generating resonance oscillations of the mirror portion due to torsional oscillations. The optical scanning element has a first resonance frequency and a second resonance frequency which generate longitudinal oscillations and lateral oscillations on a lower region side and a high region side of a resonance frequency of the torsional oscillations respectively. Outputting of a drive signal is started by setting a frequency of a drive signal which is used for oscillating the optical scanning element to a specific frequency which falls between the first resonance frequency and the second resonance frequency and is higher than the resonance frequency of the torsional oscillations and, thereafter, the frequency of the outputted drive signal is shifted to the resonance frequency of the torsional oscillations after outputting of the drive signal is started.

The invention discloses a voice coil motor control method and a lens focusing system. Coil current of a voice coil motor is controlled to enable current of a coil moving from a middle displacement position to a target position and current of the coil moving from an initial position to the middle displacement position to be centrally symmetric relative to middle points (I1 / 2 and t1 / 2), and accordingly the speed of the coil of the voice coil motor can be zero when the coil reaches the target position. By means of the voice coil motor control method, the resonance oscillation of the voice coil motor can be effectively eliminated, and control time is short.

The invention discloses a passive wireless mouse and a passive wireless keyboard based on wireless power transmission, belongs to the field of computer devices, and aims to solve the problem that the existing wireless mouse and the wireless keyboard generally require than a mouse pad is externally connected with a power supply. The passive wireless mouse based on wireless power transmission comprises a USB (universal serial bus) emission source, a mouse pad and a mouse, wherein the USB emission source comprises a USB plug, a wireless keyboard-mouse data transmission module, an energy excitation circuit and a transmitting coil; the energy excitation circuit converts a direct current power into alternating current with the frequency f, and excites an alternating magnetic field in the transmitting coil; an LC resonance circuit in the mouse pad generates resonance oscillation with the alternating magnetic field to generate an induced magnetic field around the mouse pad; the induced magnetic field generates induced electromotive force to supply power for the mouse in a mouse receiving coil. The passive wireless keyboard based on wireless power transmission comprises a USB emission source and a keyboard, wherein an LC resonance circuit in the keyboard generates resonance oscillation with the alternating magnetic field; the induced electromotive force is generated in a keyboard receiving coil to supply power to the keyboard.

The invention relates to an MEMS (Micro-electromechanical Systems) annular vibratory gyroscope and in particular relates to an anti-high-impact S-shaped elastic beam MEMS annular vibratory gyroscope harmonic oscillator structure, aiming at solving the problem that the anti-impact performance of an existing MEMS vibratory gyroscope is poor. The anti-high-impact S-shaped elastic beam MEMS annular vibratory gyroscope harmonic oscillator structure comprises an annular resonance oscillation mass, a cylindrical central anchor point and spoke-shaped elastic supporting suspension arms, wherein the cylindrical central anchor point is located at an inner cavity of the annular resonance oscillation mass; the axis of the cylindrical central anchor point is overlapped with the axis of the annular resonance oscillation mass; eight spoke-shaped elastic supporting suspension arms are arranged; the eight spoke-shaped elastic supporting suspension arms are arrayed at equal distance around the axis of the cylindrical central anchor point; each spoke-shaped elastic supporting suspension arm is composed of a firs sheet-shaped elastic supporting suspension arm, an S-shaped elastic supporting suspension arm and a second sheet-shaped elastic supporting suspension arm. The anti-high-impact S-shaped elastic beam MEMS annular vibratory gyroscope harmonic oscillator structure is applicable to the fields of weapon guidance, aerospace, automobile industry, biomedicine, consumer electronics and the like.