Abstract: External device circuitry self-tunes so that current is being driven through a coil at a resonant frequency of the tank circuit including the coil. The self-tuning nature of the driver circuitry enables adaptation within a cycle to changes in the resonant frequency such as those due to changing loads on the coil from environmental factors. The self-tuning circuitry monitors the direction of current flow in the tank circuit so that during a non-driven phase of a two-phase cycle, the circuitry detects the current naturally changing directions and then activates the driver circuitry to drive current into the tank circuit in phase with the natural direction of current flow. Unity power factor is approximated while driving the coil despite changes in resonance. Power being driven into the tank circuit may then be measured at the approximation of unity power factor to control the amount of power being applied.

Abstract: RF communications circuitry, which includes a first RF filter structure and RF detection circuitry, is disclosed. The first RF filter structure includes a first group of RF resonators, which include a first pair of weakly coupled RF resonators coupled to a signal path of a first RF signal. One of the first group of RF resonators provides a first sampled RF signal. The RF detection circuitry detects the first sampled RF signal to provide a first detected signal. The first RF filter structure adjusts a first filtering characteristic of the first RF filter structure based on the first detected signal.

Abstract: A resonant wireless power system includes a source circuit having a source coil, an ac driver with a first resistance, representing the equivalent output impedance of the ac driver, and a matching network. A current probe measures the magnitude signal of the instantaneous source coil current. A voltage probe measures the instantaneous ac driver voltage. A phase detector compares the phase of the instantaneous source coil current and the instantaneous ac driver voltage, and produces a first output signal proportional to the phase difference. A first amplifier compares the magnitude signal and a target signal, and produces an error signal proportional to the difference. A first compensation filter produces the control voltage that determines the ac driver supply voltage. A second amplifier amplifies the first output signal. A second compensation filter produces the control voltage that determines the impedance of a variable element in the source circuit.

Abstract: An EMI filter network may be used to provide interference filtering for multiple loads (referred to collectively as a dynamic load). In one aspect, the EMI filter network includes electrical switches that establish different configurations or arrangements of passive circuit elements (e.g., inductors and capacitors) where each configuration generates a different filter value. The EMI filter network may be communicatively coupled to a controller which changes the configuration of the EMI filter network using the switches in response to the dynamic load changing operational states. For example, each configuration of the EMI filter network may correspond to one of the operational states of the dynamic load. Thus, as the operational state of the dynamic load changes—e.g., different motors become operational—the controller alters the configuration of the EMI filter network to provide a filter value that corresponds to the current operational state of the dynamic load.

Abstract: The present invention relates to a new method and apparatus for improvement of High Frequency Reconstruction (HFR) techniques using frequency translation or folding or a combination thereof. The proposed invention is applicable to audio source coding systems, and offers significantly reduced computational complexity. This is accomplished by means of frequency translation or folding in the subband domain, preferably integrated with spectral envelope adjustment in the same domain. The concept of dissonance guard-band filtering is further presented. The proposed invention offers a low-complexity, intermediate quality HFR method useful in speech and natural audio coding applications.

Abstract: The present invention relates to a new method and apparatus for improvement of High Frequency Reconstruction (HFR) techniques using frequency translation or folding or a combination thereof. The proposed invention is applicable to audio source coding systems, and offers significantly reduced computational complexity. This is accomplished by means of frequency translation or folding in the subband domain, preferably integrated with spectral envelope adjustment in the same domain. The concept of dissonance guard-band filtering is further presented. The proposed invention offers a low-complexity, intermediate quality HFR method useful in speech and natural audio coding applications.

Abstract: The present invention relates to a new method and apparatus for improvement of High Frequency Reconstruction (HFR) techniques using frequency translation or folding or a combination thereof. The proposed invention is applicable to audio source coding systems, and offers significantly reduced computational complexity. This is accomplished by means of frequency translation or folding in the subband domain, preferably integrated with spectral envelope adjustment in the same domain. The concept of dissonance guard-band filtering is further presented. The proposed invention offers a low-complexity, intermediate quality HFR method useful in speech and natural audio coding applications.

Abstract: The present invention relates to a new method and apparatus for improvement of High Frequency Reconstruction (HFR) techniques using frequency translation or folding or a combination thereof. The proposed invention is applicable to audio source coding systems, and offers significantly reduced computational complexity. This is accomplished by means of frequency translation or folding in the subband domain, preferably integrated with spectral envelope adjustment in the same domain. The concept of dissonance guard-band filtering is further presented. The proposed invention offers a low-complexity, intermediate quality HFR method useful in speech and natural audio coding applications.

Abstract: RF communications circuitry includes an RF filter structure, which includes a group of resonators, a group of cross-coupling capacitive structures, and a group of egress/ingress capacitive structures, is disclosed. Each of the group of cross-coupling capacitive structures is coupled between two of the group of resonators. A first portion of the group of egress/ingress capacitive structures is coupled between a first connection node and the group of resonators. A second portion of the group of egress/ingress capacitive structures is coupled between a second connection node and the group of resonators.

Abstract: A filter system that filters WCS signals received by a satellite radio antenna if the WCS signals have a high enough signal strength where they could overwhelm the satellite radio signals and prevent the satellite radio from operating. The filter system includes a coupling circuit that couples off a small portion of the signal received by the antenna and sends it to a detector that detects the signal strength of the coupled off portion of the signal. If the signal strength exceeds a predetermined threshold, the detector provides a control signal to a switch that directs the signal received by the antenna to a WCS filter to filter out the WCS signals, where the switch otherwise causes the signal received by the antenna to be sent directly to the radio.

Abstract: A method and apparatus are disclosed for filtering a signal, such as a transmit communication signal with a configurable notch filter. The configurable notch filter may attenuate a set of frequencies near a selected notch frequency. In some embodiments, the configurable notch filter may include a variable resistor, a variable capacitor, a first inductor, and a second inductor. The variable resistor may be configured to compensate for resistive losses within the configurable notch filter. The variable capacitor may be configured to determine the set of frequencies to be attenuated.

Abstract: Systems, methods, and devices are provided for estimating when preventive maintenance of power capacitors is called for. Such a system may include, for example, a voltage sensor, a current sensor, and data processing circuitry. The voltage sensor may measure a voltage difference across a phase of a power capacitor. The current sensor may measure a current across the phase of the power capacitor. The data processing circuitry to determine a first instantaneous indication of a difference between a nominal capacitance of the power capacitor and an actual value of the power capacitor based at least in part on the measured first voltage difference and first current.

Abstract: A system, apparatus, and method directed to impedance matching an antenna with a transmitter for non-directional radio beacons. The apparatus includes an L-type impedance network comprising non-capacitive elements and at least one variable inductor on each branch of the impedance network. Also, system, apparatus, and method directed to providing a low power signal for tuning the antenna. The apparatus includes an impedance matching network and a signal generator. Also, a system, apparatus, and method directed to providing an estimate of near-field strength of a signal from an antenna. The apparatus includes an impedance matching network, a near-field signal strength detector, and microcontroller configured to estimate the near-field signal strength. Corresponding systems includes using the respective apparatuses between an antenna and a transmitter. Corresponding methods are directed to the use of the apparatuses and systems.

Abstract: A receiver includes a first amplifier having an input for receiving a radio frequency (RF) signal, and an output for providing an amplified RF signal, a switch section for selectively switching the RF signal onto one of a plurality of nodes, and a filter section comprising a plurality of filters coupled to respective ones of the plurality of nodes. A first filter of the plurality of filters comprises a first variable capacitor coupled in parallel with an inductance leg between a corresponding one of the plurality of nodes and a power supply voltage terminal, wherein the first variable capacitor has a capacitance that varies in response to a tuning signal, and the inductance leg comprises a first inductor in series with an effective resistance, wherein the effective resistance has a value related to an upper cutoff frequency to be tuned by the first filter.

Abstract: An apparatus to filter electromagnetic waves includes a cavity and one or more tuning circuits. The cavity is configured to receive the electromagnetic waves and has a resonant frequency. The one or more tuning circuits are disposed proximate to or in the cavity. The one or more tuning circuits and the cavity are configured to filter the electromagnetic waves and the resonant frequency of the cavity is based on the one or more tuning circuits.

Abstract: A method and apparatus for selective programmable filtering using analog circuits with time-varying components (e.g., resistances, capacitances) is presented. An analog front end receives an electronic signal and filters said signal by a passive or active continuous-time filter, having a combination of equivalent memory-less (e.g., resistive) and memory (e.g., capacitive or inductive) elements. A variable resistor circuit allows switching through a range of values to control one or more of the equivalent resistances of the passive or active continuous-time filter. The variable resistors are controlled using a control circuit to periodically modulate the resistances in the continuous-time filter between periodic sampling instances, such as during analog to digital conversion. Such periodic modulation of the resistances in the continuous-time filter allows for the programming and enhancement of the selectivity of said filter.

Abstract: A fast-response high-order low-pass filter circuit is provided. The circuit includes a plurality of low pass filter (LPF) poles that are connected in series, a forward bypass channel that includes a first delta voltage module that conducts at a first predetermined voltage and a first impedance module that provides a first impedance and is in series with the first delta voltage module, and a reverse bypass channel that includes a second delta voltage module that conducts at a second predetermined voltage and a second impedance module that provides a second impedance and is in series with the second delta voltage module. The forward and reverse bypass channels are arranged to bypass current around at least one of the plurality of LPF poles when a voltage difference across the at least one of the plurality of LPF poles exceeds one of the first predetermined voltage and the second predetermined voltage.

Abstract: An apparatus and method for matching antenna impedance in a mobile station are provided. In implementation, a mobile station receives power control information including information for controlling transmit power of the mobile station, generates matching control information for antenna impedance matching based on the received power control information, and performs antenna impedance matching depending on the generated matching control information.

Abstract: Disclosed are an impedance matching apparatus and an impedance matching method thereof. The impedance matching apparatus performs impedance matching between a front end module and an antenna. The impedance matching apparatus includes a switching unit to selectively select multiple-band RF input signals, a power amplifying unit to amplify the RF input signal selected from the switching unit, a reflected power measuring unit to measure a reflection coefficient for the RF input signal, a matching unit to adjust a variable device so that the reflection coefficient is minimized, and a controller to provide a variable device value allowing the minimum reflection coefficient based on the amplified RF input signal and the reflection coefficient.

Abstract: An RF impedance matching network includes a transformation circuit configured to provide a transformed impedance; a first shunt circuit in parallel to the RF input, the first shunt circuit including a first shunt variable capacitance component comprising (a) a plurality of first shunt capacitors coupled in parallel, and (b) a plurality of first shunt switches coupled to the plurality of first shunt capacitors and configured to connect and disconnect each of the plurality of first shunt capacitors to a first virtual ground; and a second shunt variable capacitance component including (a) a plurality of second shunt capacitors coupled in parallel, and (b) a plurality of second shunt switches coupled to the plurality of second shunt capacitors and configured to connect and disconnect each of the plurality of second shunt capacitors to a second virtual ground.

Abstract: An apparatus for optical modulation is provided. The apparatus includes a modulator structure and a heater structure. The modulator structure comprises a ring or disk optical resonator having a closed curvilinear periphery and a pair of oppositely doped semiconductor regions within and/or adjacent to the optical resonator and conformed to modify the optical length of the optical resonator upon application of a bias voltage. The heater structure comprises a relatively resistive annulus of semiconductor material enclosed between an inner disk and an outer annulus of relatively conductive semiconductor material. The inner disk and the outer annulus are adapted as contact regions for a heater activation current. The heater structure is situated within the periphery of the optical resonator such that in operation, at least a portion of the resonator is heated by radial conductive heat flow from the heater structure.

Abstract: Methods for the design of microwave filters comprises comprising preferably the steps of inputting a first set of filter requirements, inputting a selection of circuit element types, inputting a selection of lossless circuit response variables, calculating normalized circuit element values based on the input parameters, and generate a first circuit, insert parasitic effects to the normalized circuit element values of the first circuit, and output at least the first circuit including the post-parasitic effect circuit values. Additional optional steps include: requirements to a normalized design space, performing an equivalent circuit transformation, unmapping the circuit to a real design space, performing a survey, and element removal optimization. Computer implement software, systems, and microwave filters designed in accordance with the method are included.

Abstract: Disclosed herein is a wireless power supplying system, including a power transmission device adapted to transmit power supplied thereto, a repeater device adapted to repeat the transmission power of the power transmission device, and a power reception device adapted to receive the power repeated by said repeater device.

Abstract: An apparatus and method for matching impedance of an antenna by using Standing Wave Ratio (SWR) information is provided. While the impedance of the impedance matching unit is controlled, a region of a Smith chart in which initial total impedance of the impedance matching unit and the antenna is located by using an SWR calculated by an SWR operation unit, and the impedance of the impedance matching unit is controlled according to the determined region, thus correctly matching the impedance of the antenna.

Abstract: A gain measurement circuit of a receiver includes a frequency mixer that receives a reception signal, mixes the reception signal with a local signal from an oscillator, and outputs an intermediate frequency signal; and a phase controller that extracts a part of the local signal, sets a different phase for the part, and outputs the part as the reception signal; wherein, for the different phase set by the phase controller, a direct-current voltage of the intermediate frequency signal output from the frequency mixer is detected, a conversion gain of the frequency mixer is obtained, and a gain of the receiver is calculated.

Abstract: A front end module for a wireless transmission/reception device has two antennas and two signal paths connected thereto. A mismatch in the antenna is identified by monitoring the transmitted power and the reflected power in the active and passive signal paths and using the powers in a controller to generate a control signal for the antenna tuner. In this case, decreasing isolation between the first and second antennas and the first and second signal paths is identified, and is compensated for using different devices, in order to ensure faster and safer antenna matching.

Abstract: A detector circuit can be used for determining the reflection coefficients of HF signals in a signal path. The detector circuit includes a bidirectional hybrid coupler, logarithmic amplifiers connected to the hybrid couple, and a subtractor having an offset connection.

Abstract: Waveforms generators include a splitter that splits a digital input signal into a number of split signals each having a split signal frequency bandwidth that is substantially similar to a digital input signal frequency bandwidth. The split signals are mixed with associated digital, harmonic signals to generate a number of digital, mixed signals, which are then converted to analog signals at an effective sample rate that is different from a first order harmonic signal of at least one of the digital, harmonic mixers. A number of analog, harmonic mixers mix the associated analog signals with associated analog, harmonic signals to generate mixed, analog signals. The mixed, analog signals are combined into an output signal having an output signal bandwidth that is greater than a bandwidth of at least one of the number of DACs.

Abstract: In a method of operating a microwave plasma abatement apparatus comprising a microwave generator, and a gas chamber for receiving microwave energy from the microwave generator and within which a plasma is generated using the microwave energy, the amount of microwave energy that is not absorbed within the gas chamber is monitored, and the power of the microwave energy generated by the microwave generator is adjusted in dependence on the monitored microwave energy.

Abstract: Provided is a control device of a LC circuit using a spiral inductor, comprising: a spiral inductor in which a first metal line connected to a first terminal and a second metal line connected to a second terminal cross at least one time to be connected in a spiral shape, and that includes at least one crossing part; at least one transistor in which a drain terminal and a source terminal are respectively connected to a first metal line portion and a second metal line portion that correspond to the crossing part; a variable capacitor that is connected to a first terminal and a second terminal of the spiral inductor in parallel; and a controller that respectively sends control signals to the transistor and the variable capacitor to control a resonant frequency or an output.

Abstract: RF communications circuitry, which includes a first RF filter structure and RF detection circuitry, is disclosed. The first RF filter structure includes a first group of RF resonators, which include a first pair of weakly coupled RF resonators coupled to a signal path of a first RF signal. One of the first group of RF resonators provides a first sampled RF signal. The RF detection circuitry detects the first sampled RF signal to provide a first detected signal. The first RF filter structure adjusts a first filtering characteristic of the first RF filter structure based on the first detected signal.

Abstract: A tuning system connected to a tunable RF circuit is described. The tuning system obtains an output of a sensing circuit and processes the output in the control circuit in order to tune one or more passive components in the tunable RF circuit. A related method is also described.

Abstract: Embodiments of radio frequency (RF) front-end circuitry are disclosed where the RF front-end circuitry includes a tunable RF filter structure and a calibration circuit. The tunable RF filter structure includes (at least) a pair of weakly coupled resonators and defines a transfer function with a passband. The calibration circuit is configured to shape the passband so that the passband defines a center frequency. Additionally, the calibration circuit is configured to detect a phase difference at the target center frequency between the pair of weakly coupled resonators and adjust the phase difference of the pair of weakly coupled resonators at the target center frequency so as to reduce a frequency displacement between the center frequency of the passband and the target center frequency. In this manner, the calibration circuit calibrates the tunable RF filter structure to correct for errors in the center frequency of the passband due to component manufacturing variations.

Abstract: RF communications circuitry includes an RF filter structure, which includes a group of resonators, a group of cross-coupling capacitive structures, and a group of egress/ingress capacitive structures, is disclosed. Each of the group of cross-coupling capacitive structures is coupled between two of the group of resonators. A first portion of the group of egress/ingress capacitive structures is coupled between a first connection node and the group of resonators. A second portion of the group of egress/ingress capacitive structures is coupled between a second connection node and the group of resonators.

Abstract: Provided is a capsule-type endoscope that has a power receiving coil that wirelessly receives an electric power from outside a body of an individual to be examined, a processing circuit that performs predetermined processing, and an adjusting reactance section that is capable of adjusting a reactance that is connected to the power receiving coil.

Abstract: There is described herein a real-time scheme, implementable in software, hardware, or a combination thereof, to detect a resonating frequency of a structure from a sensed signal and dynamically set the center frequency of an adaptive compensator for effective attenuation of the resonating frequency.

Abstract: Embodiments include methods of tuning state variable filters. Examples include state variable filters whose center frequencies can be tuned using variable gain blocks coupled to outputs of filter integrators. First- and second-order state variable filters may operate on signals in parallel and their outputs combined to produce a filtered output. Filters may be tuned to pass or reject signals depending on the application; sample applications include, but are not limited to: agile filtering; spectrum analysis; interference detection and rejection; equalization; direct intermediate-frequency transmission; and single-sideband modulation and demodulation.

Abstract: A tuner includes a plurality of paths, and at least one of the paths includes a front-end filter circuit, an amplifier, and a trace filter. The trace filter includes a varactor and an inductor, which are coupled to an output end of the amplifier. Further, the amplifier and the varactor of the tuner are packed in a complementary metal-oxide semiconductor (CMOS) chip.

Abstract: Tunable notch filters and control loop systems and methods can include a tunable notch filter providing a stop band, a sensing circuit in communication with the tunable notch filter and adapted to determine a phase change between a reference signal and a signal reflected from the tunable notch filter, and a control loop in communication with the tunable notch filter and the sensing circuit, the control loop being operable to adjust the tunable notch filter to modify the phase change.

Abstract: A method and apparatus for automatic compensation of insertion loss in signals transmitted over conductors is presented. The present invention is particularly applicable to the transmission of signals over long lengths of CAT-5 or similar twisted-pair cables. A reference signal having a known form and strength (e.g. a pulse signal) is provided to each pair of conductors carrying a component of a signal from a transmitter to a receiver. The receiver includes adjustable gain amplifiers for each conductor pair over which a component of the signal is transmitted. The gains of the amplifiers are initially set at an initial level (e.g., their maximum gain) to allow detection of the reference signal. Once the reference signal is detected in a conductor pair, the amplifier gains are adjusted such that the level of the reference signal is restored approximately to its original form and strength.

Abstract: A tunable RF filter comprises a signal transmission path having an input and output, a plurality of resonant elements disposed along the signal transmission path between the input and output, and a set of non-resonant elements coupling the resonant elements together to form a stop band having a plurality of transmission zeroes corresponding to respective frequencies of the resonant elements, and at least one sub-band between the transmission zeroes. The set of non-resonant elements comprises a first plurality of non-resonant elements respectively coupled in parallel with the resonant elements, and a second plurality of non-resonant elements respectively coupled in series with the resonant elements. The first plurality of non-resonant elements comprises at least one variable non-resonant element for selectively introducing at least one reflection zero within the stop band to create a pass band in one of the one sub-band(s) without varying any of the second plurality of non-resonant elements.

Abstract: An integrated circuit (IC) for compensating for a package inductance is disclosed. A first ground pad is directly connected to an on-chip ground node. A second IC ground pad is connected to the on-chip ground node via a tunable capacitor circuit, where the capacitance of the tunable capacitor circuit resonates with the package inductance at the operating frequency of the IC.

Abstract: A resonant matching circuit (310) for matching a resonant frequency of a wireless power transfer system to a frequency of a power signal comprises a switch (311) connected in parallel with a resonant element (302) of the wireless power transfer N system; and a controller (312) connected to the switch (311) and configured to detect a zero-voltage level crossing of a signal flowing through the resonant element (302) and to close the switch (311) for a predefined amount of time upon detection of the zero-voltage level crossing, wherein closing the switch (311) for the predefined amount of time adds any one of an inductive value and a capacitive value to the resonant frequency of a wireless power transfer system.

Abstract: An electromagnet structure comprises a magnetic shell having a cavity, a magnetic pole located within the cavity and having a magnetic gap for focusing a magnetic field on a magnetically tunable filter, a conductive coil located within the cavity of the magnetic shell and forming multiple turns around the magnetic pole, and a heater located within the cavity of the magnetic shell and configured to maintain the conductive coil at a substantially constant temperature when the magnetically tunable filter is tuned to different frequencies.

Abstract: The present invention relates to a method for estimating properties of a transmission line by means of features of a noise spectrum generated by noise entering said transmission line at an intermediate location between the ends of the line. The invention provides possibility to estimate a number of properties, e.g. length of a portion of the transmission line, line attenuation of said line portion and even line termination.

Abstract: A filtering circuit with BAW type acoustic resonators having at least a first quadripole and a second quadripole connected in cascade, each quadripole having a branch series with a first acoustic resonator of type BAW and a branch parallel with each branch having an acoustic resonator of type BAW, the first acoustic resonator having a frequency of resonance series approximately equal to the frequency of parallel resonance of the second acoustic resonator, the branch parallel of the first quadripole having a first capacitance connected in series with the second resonator and, in parallel with the capacitance, a first switching transistor to short circuit the capacitance.

Abstract: In a phased array antenna that has a configuration in which a plurality of antenna panels, in each of which a plurality of antenna elements are arrayed, are connected in the form of a plane and that radiates power transmission microwaves in the arrival direction of a pilot signal sent from an electric-power receiving facility (rectenna system), by controlling the phases of signals input to and output from the antenna elements. An arithmetic processing section, which is provided in each of the antenna panels, calculates the phase shifts of power transmission microwaves to be radiated from the antenna elements. Then, the phase information indicating the phase shifts calculated by the arithmetic processing section is sent to at least three adjacent antenna panels by a transmission and reception section provided in each of the antenna panels.

Abstract: A time-variant antenna is disclosed that uses a switched capacitor array in silicon to improve the performance and integration options of the time-variant antenna. Parasitic effects of the interface between the on-board antenna and on-silicon switched capacitor array are considered and the antenna is tuned to compensate for these effects. The switched capacitor array provides high linearity, lower cost, and reduced size, relative to prior art antenna implementations.

Abstract: A nonreciprocal transmission line apparatus is provided with a cascade connection of unit cells between ports. Each unit cell includes a transmission line part for a microwave signal, and shunt branch circuits equivalently including inductive elements. Each unit cells has spontaneous magnetization or is magnetized by an external magnetic field so as to have gyrotropy by being magnetized in a magnetization direction different from a propagation direction of the transmission line part. In each of the unit cells, the shunt branch circuits includes a first stub conductor formed on one side with respect to a plane composed of the propagation direction and the magnetization direction, and a second stub conductor formed on the other side with respect to the plane, and the stub conductors have different electric length from each other.

Abstract: Tuning a programmable power line filter, the power line filter including a live line, a neutral line, and a ground line connected to input terminals of the filter on an input side of the filter, the live line and the neutral line connected through inductors in the filter to output terminals on an output side of the filter, X-capacitors selectably connected through tuning switches between the live line and the neutral line, Y-capacitors selectably connected through tuning switches between the live line and ground and/or between the neutral line and ground, and a tuning control circuit connected to the tuning switches and selectably connected through one or more programming switches to the load, including measuring by the tuning control circuit the input impedance of the load and programming by the tuning control circuit the tuning switches in dependence upon the input impedance of the load.