| Entries |
| Document | Title | Date |
|---|
| 20080211597 | Filter Circuit - A filter circuit including first and second real filters of a zero-IF scheme. The first and second real filters receive an I component and a Q component separated from a reception signal, respectively; and a switch section for producing a complex filter by switchably connecting the first and second real filters through interconnection elements. The switch section further receiving a switching signal for connecting the first and second real filters, thereby switching from the zero-IF scheme to a low-IF scheme. | 09-04-2008 |
| 20080224792 | Methods and apparatuses for suppressing interference - Embodiments of the invention provide an adaptive notch filter that employs a power detector as a feedback control mechanism to steer the notch filter. One such embodiment of the invention provides adaptive control of the notch filter capacitor to tune the notch filter frequency based upon a diode power detector. One embodiment of the invention provides a system including multiple cascaded adaptive notch filters each having a feedback control method from a power detector to separately control each filter. For one embodiment of the invention a method is disclosed for tuning an adaptive notch filter using a dithering process to determine a minimum power output at the power detector. One embodiment includes an adaptive notch filter implementing a device with a tunable resonance frequency. | 09-18-2008 |
| 20090121802 | Systems and Methods for Tuning Filters - Methods, systems and apparatus for filter design, analysis and adjustment are provided. Various embodiments may include, for example, methods, systems and apparatus for electric signal filter tuning. Embodiments may also include design techniques for planar electric signal (e.g., RF signals) filter tuning. In at least an embodiment of the present invention a technique for filter tuning is provided which may include parameter extraction, optimization and tuning recipes techniques that may require only a single permanent filter tuning. In at least another embodiment a system and method of filter design, analysis and adjustment according to the present invention includes use of tuning that may be set using a mechanical scribing tool or a laser trimming device. In at least one other embodiment, a filter tuning technique may be provided and include providing trimming tabs on a resonator edge that may be disconnected or trimmed for filter tuning. | 05-14-2009 |
| 20090128249 | Variable Capacitance Circuit - The invention relates to a variable capacitance circuit which achieves reduction in both of distortion and current consumption and furthermore achieves requirements of high power handling capability, cost reduction, and downsizing of the circuit. The variable capacitance circuit includes a first variable capacitance element unit having n pieces (where n is a natural number of two or more) of variable capacitance capacitor connected in series with respect to high frequency and in parallel with respect to direct current, each of the variable capacitance capacitors including one or more variable capacitance elements, each of which includes a dielectric layer with dielectric constant varying according to an applied direct-current voltage and a pair of electrodes sandwiching the dielectric layer therebetween, and a second variable capacitance element unit which has an applied voltage amplitude smaller than a voltage amplitude of high frequency signal applied to the first variable capacitance element unit, the second variable capacitance element unit including one piece of the variable capacitance elements or having m pieces (where m is a natural number smaller than n) of the variable capacitance elements connected. | 05-21-2009 |
| 20090243747 | METHODS AND DEVICES FOR COMPENSATING A SIGNAL USING RESONATORS - Compensation of a signal using resonators as well as related methods and devices are described. Some embodiments include methods and devices for performing frequency compensation on a signal. | 10-01-2009 |
| 20100127791 | FILTER-TRACKING AND CONTROL METHOD - A method to track and control the resonance frequency of a band-pass filter provides a solution for the sensitivity limitations against temperature and process variations. A phase sensing module obtains the phase difference between the input and output and a negative feed-back control architecture can be used to tune the filter's resonance over the input RF frequency. | 05-27-2010 |
| 20100148883 | MEASUREMENT AND CONTROL OF ELECTROMAGNETIC INTERFERENCE - The average EMR emissions of an electronic device may be reduced by implementing an electrically-active modulated termination. For example, the impedance may be continuously varied at one or more termination locations between two metal substructures to cause a like variation in the amplitude of each component of the EMR. According to one approach, cyclically varying the electrical impedance with a period of less than the time interval over which the EMR is measured will result in a reduction in the average measured EMR. | 06-17-2010 |
| 20100253442 | Tank Tuning for Band Pass Filter Used in Radio Communications - A tuning method and circuit for an LC tank resonant circuit, including an inductor and a variable capacitor, are described. In a tuning mode, an RF input signal is applied to an input port of the circuit, and the RF output signal is monitored as a variable capacitor control input is varied. A peak output is detected, and the corresponding variable capacitor control input is stored, and applied to the variable capacitor in an operating mode. In one embodiment, the variable capacitor control input is adjusted for delay in the peak detection process. In one embodiment, the variable capacitor comprises a coarse capacitor and a fine capacitor; the tuning procedure is repeated for each capacitor; and both coarse and fine variable capacitor control inputs are stored and applied to the respective capacitors in operating mode. | 10-07-2010 |
| 20110001573 | FREQUENCY HOPPING BAND-STOP FILTER - A digitally-tunable filter includes a tunable filter circuit ( | 01-06-2011 |
| 20110128087 | Tuning A Programmable Power Line Filter - 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. | 06-02-2011 |
| 20110193651 | INTEGRATED CIRCUIT, NON-CONTACT IC CARD, READER/WRITER, WIRELESS COMMUNICATIONS METHOD, AND COMPUTER PROGRAM - An integrated circuit, a non-contact IC card, a reader/writer, a wireless communications method, and a computer program are provided to improve communication. The integrated circuit configured to execute wireless communication by means of magnetic field. The integrated circuit has a resonance circuit having resonance frequencies of a plurality of levels, a confirmation block configured to confirm whether a predetermined condition is satisfied, and a switching block configured to change the resonance frequencies if the predetermined condition is found satisfied as a result of the confirmation. | 08-11-2011 |
| 20110227664 | Frequency Agile Filter Using a Digital Filter and Bandstop Filtering - The present invention is a hybrid RF-digital signal processor-based filter for multiband radio architectures systems capable of spectrum re-farming and software defined radios. It performs low-loss frequency agile multiple notch filtering at RF where a large dynamic range exists at a filter input between signals in a stopband and passband. It is a frequency dependent signal attenuation apparatus having two paths connected together by directional couplers. The first path comprising a component such as a delay component or duplexer. The second path comprising a bandstop filter connected to a down converter, a digital filter, and an up converter. At the output of a power amplifier, the invention can be used to attenuate spurs, or noise within bands with strict emission constraints. At the input of a low noise amplifier, the invention can be used to attenuate blockers and transmitter noise outside of the receiver passband. | 09-22-2011 |
| 20110227665 | Frequency Agile Filter Using a Digital Filter and Bandstop Filtering - The present invention is a hybrid RF-digital signal processor-based filter for multiband radio architectures, systems capable of spectrum re-farming and software defined radios It performs low-loss frequency agile multiple notch filtering at RF where a large dynamic range exists at a filter input between signals in a stopband and passband It is a frequency dependent signal attenuation apparatus having two paths connected together by directional couplers The first path comprising a component such as a delay component or duplexer The second path comprising, in series, a down converter, a digital filter, an up converter, and a bandstop filter At the output of a power amplifier, the invention can be used to attenuate spurs, or noise within bands with strict emission constraints At the input of a low noise amplifier, the invention can be used to attenuate blockers and transmitter noise outside of the receiver passband. | 09-22-2011 |
| 20120098613 | FREQUENCY-TUNABLE FILTER - A frequency tunable filter is disclosed. The frequency tunable filter includes a filter unit that can tune a frequency band of a frequency signal being filtered, a communication module that receives a control signal for controlling the tuning of the frequency band, and a control unit that controls the tuning of the frequency band based on the control signals. The disclosed filter can control the tuning of the filter's frequency band wirelessly. | 04-26-2012 |
| 20120105167 | PACKAGE INDUCTANCE COMPENSATING TUNABLE CAPACITOR CIRCUIT - 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. | 05-03-2012 |
| 20120286892 | MEMS TUNABLE NOTCH FILTER FREQUENCY AUTOMATIC CONTROL LOOP SYSTEMS AND METHODS - 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. | 11-15-2012 |
| 20130015923 | AUTOMATIC WAVEGUIDE SWITCH-BASED PROTECTION SYSTEMS FOR RECEIVER CIRCUITRYAANM MCKINLEY; WILLIAMAACI CLERMONTAAST FLAACO USAAGP MCKINLEY; WILLIAM CLERMONT FL USAANM SIMS; FRANK R.AACI APOPKAAAST FLAACO USAAGP SIMS; FRANK R. APOPKA FL USAANM GRAY; STEVEN G.AACI ORLANDOAAST FLAACO USAAGP GRAY; STEVEN G. ORLANDO FL US - An automatic protection system for receiver circuitry includes a waveguide switch having a permanent magnet attached to a rotatable manifold and at least one electromagnet axially surrounding the rotatable manifold. An automatic actuation circuit is coupled to the waveguide switch. The automatic actuation circuit includes an RF power detector for detecting incident RF power around the rotatable manifold and generating a detection signal therefrom, a controller coupled to receive the detection signal and for generating at least a first control signal based on the detection signal, and a magnet current driver coupled to receive the first control signal and coupled to the electromagnet. The magnet current driver provides a first drive signal responsive to the first control signal that automatically rotates the rotatable manifold into a protected position that implements a protected path, such as when the incident RF power exceeds a predetermined RF power level. | 01-17-2013 |
| 20130027152 | DRIFT STABILIZATION OF MAGNETICALLY TUNABLE FILTER BY TEMPERATURE REGULATION AND MECHANICAL ISOLATION OF ELCTROMAGNET COIL - 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. | 01-31-2013 |
| 20130162365 | Calibration of a Resonance Frequency Filter - Calibrating a frequency filter includes applying a series of input electrical signals at different frequencies to a shock sensor, using circuitry to identify a particular one of the frequencies as a resonance frequency of the shock sensor based on responses of the shock sensor to the series of input signals, and setting a center frequency of the notch filter equal to the particular frequency identified as the resonance frequency of the shock sensor. | 06-27-2013 |
| 20130271233 | APPARATUS AND METHOD OF TUNING MICROWAVE FILTER - Disclosed are an apparatus and a method of tuning a microwave filter. An apparatus for tuning a microwave filter according to the present invention includes: a measurement device configured to measure a scattering (S) parameter curve of a microwave filter desired to be tuned; a control device configured to perform tuning so that a shape of the S parameter curve according to a movement of a preselected tuning screw is matched to a shape of a target S parameter curve, and then determine a quantity of transfer of the tuning screw based on feature points on the S parameter curve by using a least squares method in which a preset weight is reflected; and a tuning device configured to move the tuning screw based on the determined quantity of transfer of the tuning screw. | 10-17-2013 |
| 20140035694 | PHASED ARRAY ANTENNA AND PHASE CONTROL METHOD THEREFOR - 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. | 02-06-2014 |
| 20140191818 | DYNAMIC RESONANT MATCHING CIRCUIT FOR WIRELESS POWER RECEIVERS - A resonant matching circuit ( | 07-10-2014 |
| 20140306777 | BI-QUAD CALIBRATION - 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. | 10-16-2014 |
| 20140327489 | DYNAMICALLY DETECTING RESONATING FREQUENCIES OF RESONATING STRUCTURES - 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. | 11-06-2014 |
| 20150035612 | CALIBRATION FOR A TUNABLE RF FILTER STRUCTURE - 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. | 02-05-2015 |
| 20150048896 | System and Method for Tuning an RF Circuit - 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. | 02-19-2015 |
| 20150084713 | FILTERING CHARACTERISTIC ADJUSTMENTS OF WEAKLY COUPLED TUNABLE RF FILTERS - 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. | 03-26-2015 |
| 20150109067 | CONTROL DEVICE OF LC CIRCUIT USING SPIRAL INDUCTOR - 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. | 04-23-2015 |
| 20150333386 | CAVITY FILTER - In one embodiment, the cavity filter includes a housing defining a cavity, and at least one post projecting from a first interior surface of the housing towards a second interior surface of the housing. The first interior surface faces the second interior surface. The cavity filter further includes a thermo electric cooler disposed on the housing. The thermo electric cooler is configured to one of cool and heat at least a portion of the housing. | 11-19-2015 |
| 20150333721 | DYNAMICALLY DETECTING RESONATING FREQUENCIES OF RESONATING STRUCTURES - 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. | 11-19-2015 |
| 20150381139 | Calibration of Step Attenuator - System and method for calibrating a step attenuator. N attenuation measurements of a step attenuator may be received, where the step attenuator includes M series-connected attenuation sections. Each attenuation section may be configured to switchably provide a respective level of attenuation, where N is greater than M, and where the step attenuator may be modeled via M+1 coefficients, including a coefficient for a no-attenuation state and respective coefficients for the attenuation sections. Values of the coefficients may be determined via least squares estimation using the N attenuation measurements, thereby calibrating the step attenuator. | 12-31-2015 |
| 20160028362 | HIGH POWER FILTER WITH SINGLE ADJUST FOR MULTIPLE CHANNELS - A RF filter system for filtering radio frequency is provided. A first plurality of capacitors, said first plurality of capacitors comprising at least a first capacitor and a second capacitor is provided. A first conductor and second conductor are wound around a first core member to forma first inductor formed from the first conductor and a second inductor formed from the second conductor, a first end of said first conductor being connected to a first end of a first load and to a first end of said first capacitor, wherein a first end of said second conductor being connected to a second end of the first load and a second end of said second capacitor. A first variable component has a first end connected to ground and a second end connected to a second end of said first capacitor and a first end of said second capacitor. | 01-28-2016 |
| 20160182013 | TUNABLE EVANESCENT-MODE CAVITY FILTER WITH CLOSED LOOP CONTROL | 06-23-2016 |
| 20190149119 | COMBINER AND DISTRIBUTOR FOR ADJUSTING IMPEDANCES OR POWER ACROSS MULTIPLE PLASMA PROCESSING STATIONS | 05-16-2019 |
