摘要:
This invention is a resonant waveguide Stark cell suitable for use in a Stark-modulated microwave spectrometer. The cell is constructed from a short length of waveguide. A Stark electrode is located inside the waveguide parallel to the broad face of the guide and insulated from the walls of the guide with narrow teflon strips. A reflector with a small coupling iris at its center is located at one end of the cell. This small coupling iris is for passing microwave energy into and out of the cell. At the other end of the cell there is an adjustable waveguide short making the small Stark cell into a tuneable cavity which can be tuned for resonance at selected microwave frequencies. Means are provided for maintaining a gas-tight compartment within the cell, and ports are provided for the introduction of the gas to be analyzed into the gas-tight compartment.
摘要:
A probe calibration device that includes a first offset element having a substantially rectangular first aperture. The probe calibration device includes a tuned pass element disposed adjacent to the first offset element. The tuned pass element has a non-rectangular second aperture. The probe calibration device includes a second offset element disposed adjacent to the tuned pass element and on a side opposite the first offset element. The second offset element has a substantially rectangular third aperture. The probe calibration device includes a backing element disposed adjacent to the second offset element. The first offset element, the tuned pass element, the second offset element and the backing element form a cavity.
摘要:
A method for tuning a filter component using size adjustment includes measuring a first frequency of a first resonant mode of a dielectric resonator component of an RF filter, said dielectric resonator component being a block of dielectric material having a cuboid shape with three pairs of opposite faces. The first resonant mode has an electric-field component oriented in a direction perpendicular to one of the pairs of opposite faces and parallel to the other two pairs of opposite faces. When a measured value of the first frequency of the first resonant mode is less than a desired value, dielectric material is removed uniformly from at least one face of the two pairs of opposite faces parallel to the electric-field component of the first resonant mode to maintain the cuboid shape of the block of dielectric material. The removal of the dielectric material may be by at least one of lapping, grinding, and milling. The first frequency of the first resonant mode is remeasured to check whether a remeasured value therefor is closer or equal to the desired value without exceeding the desired value. The method is also applicable for tuning multiple modes of dielectric resonator component in the form of a block of dielectric material having a cuboid shape, as well as for tuning multiple modes in dielectric resonator components in the form of blocks of dielectric material having cylindrical and spherical shapes.
摘要:
A method for determining parameters of a wireless power transmission system is disclosed where the wireless power transmission system transmits power from a power transmission device to a power reception device via electric field coupling. The parameters include a coupling coefficient ke of an electric field coupling unit that is formed of active electrodes and passive electrodes of the power transmission device and the power reception device.
摘要:
A method to operate a resonator is provided herein. As illustrated with an example, the resonator is excited by means of a periodic excitation signal with an integer number of at least two signal components with one specified frequency each. A response signal of the resonator is determined at the specified frequencies of the at least two signal components of the excitation signal. Eventually, parameters of a model illustrating the behavior of the resonator as a function of the response signal are calculated based on the response signal.
摘要:
A system includes a bottle, a first wire, a second wire, a current probe and an output line. The bottle holds a dielectric liquid therein. The first wire is disposed longitudinally on the bottle and generates a first oscillating electrical current in response to an electromagnetic wave, wherein the first oscillating electrical current thereby generates a corresponding first oscillating magnetic field. The second wire is disposed in parallel with the first wire on the bottle and generates a second oscillating electrical current in response to the electromagnetic wave, wherein the second oscillating electrical current thereby generating a corresponding second oscillating magnetic field. The current probe is arranged to surround the bottle such that the bottle is rotatable within the current probe or such that the current probe is rotatable around the bottle.
摘要:
An electromagnetic method for sensing the relative position of two items using coupled tuned resonant circuits. Two co-resonant tuned circuits are attached to two items 1 and 2 that move relative to one another. The coupling between the circuits is arranged to vary with their relative physical position. One of the tuned circuits is excited at or close to its resonant frequency. The degree of coupling between the tuned circuits is detected by its effect on the way the resultant oscillation changes with time, and this allows the relative position of the items to be established. The inductive elements of the tuned circuits can comprise anti-symmetrical regions 3, 4, 9 and 10 so that the magnetic fields generated by the oscillations are localised and sensitivity to externally applied magnetic fields is minimised. The inductive elements can be implemented directly as printed circuit board tracks.
摘要:
A monitoring circuit monitors a piezoelectric crystal for changes in its resonant frequency as a film of material is vacuum deposited on it, e.g. to control a source of vapors of the material. A controllable frequency generator generates a drive signal of a accurately known frequency and phase within a band of RF frequencies that includes the resonant frequency of the crystal. The RF signal is applied through a duplexing circuit to the crystal, and a response signal is applied through the duplexing circuit to a signal amplifier and limiter circuit to a phase detector. The phase detector is also supplied with the RF drive signal, and has a phase output signal which is zero when the crystal is at resonance, and is negative or positive when the applied RF signal is below or above resonance, respectively. A micro-controller can be employed for controllably sweeping the frequency of the drive signal and then monitoring the frequencies at which the phase detector signal indicates zero, to identify the frequency of each of the one or more resonances. A cable compensation control circuit can also be coupled to the duplexing circuit for balancing the reactance of the conductive paths associated with the crystal. This can include a voltage controlled capacitance and a portion of a transformer within the duplexing circuit.
摘要:
A frequency domain sensing system is disclosed for sensing the position of a high energy beam of charged particles traveling within a housing which comprises a plurality of sensors positioned in the wall of the housing radially around the axis of the beam. Each of the sensors further comprises a first electrode of predetermined shape received in a bore in the housing to define a fixed capacitance and an inductance structure attached to the electrode to provide an inductance for the sensing means which will provide an LC circuit which will resonate at a predetermined frequency known to exist in the beam of charged particles. The sensors are further provided with tuning apparatus associated with the inductance structure to vary the amount of the inductance to thereby tune the sensors to the predetermined frequency prior to transmission of the signal to signal detection circuitry.