Bridge Type Patents (Class 333/170)
  • Patent number: 11923322
    Abstract: An apparatus and method for a frequency based integrated circuit that selectively filters out unwanted bands or regions of interfering frequencies utilizing one or more tunable notch or bandpass filters or tunable low or high pass filters capable of operating across multiple frequencies and multiple bands in noisy RF environments. The tunable filters are fabricated within the same integrated circuit package as the associated frequency based circuitry, thus minimizing R, L, and C parasitic values, and also allowing residual and other parasitic impedance in the associated circuitry and IC package to be absorbed and compensated.
    Type: Grant
    Filed: December 7, 2021
    Date of Patent: March 5, 2024
    Assignee: pSemi Corporation
    Inventors: William R. Smith, Jr., Jaroslaw Adamski, Dan William Nobbe, Edward Nicholas Comfoltey, Jingbo Wang
  • Patent number: 11233494
    Abstract: An electronic circuit includes a first filter and a second filter. The first filter passes a first frequency component of a first harmonic frequency generated by a first voltage source to form a potential difference in a chamber and a second frequency component of a second harmonic frequency higher than the first harmonic frequency. The second filter removes the first frequency component and the second frequency component received from the first filter. The second harmonic frequency is included in a first frequency band determined based on a capacitance of the second filter.
    Type: Grant
    Filed: October 4, 2019
    Date of Patent: January 25, 2022
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hyungjoon Kim, Je-Dong Lee, Younghoon Kwon, Myoungwoon Kim, Il-Woo Kim, Jiwoon Im, Jaewon Jung, Hee Jong Jeong
  • Patent number: 10892729
    Abstract: A non-ferromagnetic electronic circulator device and system is described. Such passive electronic circulator devices may include a plurality of ports that include a discrete arrangement of resistors, capacitors and inductors that form a fully connected S parameter matrix. Signals that enter a first port of the circulator only exit from the second port, signals entering the second port only exit from the third port, signals entering the third port only exit the fourth port, and signals entering the fourth port, only exit the first port.
    Type: Grant
    Filed: March 7, 2018
    Date of Patent: January 12, 2021
    Assignee: Mission Microwave Components LLC
    Inventor: Michael Scott Andrews
  • Patent number: 10340876
    Abstract: A high performance integrated tunable impedance matching network with coupled merged inductors. Embodiments include a combination of merged multiport constructively coupled spiral inductors and tunable capacitors configured to reduce insertion losses, circuit size, and optimization time while maintaining a high Q factor for the coupled spiral inductors. Some embodiments integrate one or more filter circuits with a tunable impedance matching network, useful in conjunction with such applications as radio frequency power amplifiers.
    Type: Grant
    Filed: February 19, 2016
    Date of Patent: July 2, 2019
    Assignee: pSemi Corporation
    Inventors: Chih-Chieh Cheng, Tero Tapio Ranta, Richard Bryon Whatley, Vikram Sekar
  • Patent number: 10320305
    Abstract: A transformer is provided between a power supply, and a load with a resistance value R, and includes a two-terminal pair circuit composed of n-number of reactance elements that are mutually connected, where n is a natural number equal to or greater than 4. With respect to any value of the resistance value R of the load, an input impedance Zin of the two-terminal pair circuit has a real number component of k·R, where k is a constant, and an imaginary number component of 0. Such a transformer has a small size and a light weight, and does not need a coil, an iron core, and the like as used in a conventional transformer.
    Type: Grant
    Filed: August 8, 2014
    Date of Patent: June 11, 2019
    Assignees: SUMITOMO ELECTRIC INDUSTRIES, LTD., NATIONAL UNIVERSITY CORPORATION TOYOHASHI OF TECHNOLOGY
    Inventors: Kenichi Hirotsu, Nobuo Shiga, Hideaki Nakahata, Takashi Ohira, Kyohei Yamada
  • Patent number: 9847892
    Abstract: Embodiments of the present disclosure provide methods and apparatus for providing feed forward equalization to a communication line by providing a resistance and a capacitance to the communication line. The method includes determining the resistance based on a desired value of feed forward equalization to provide to a communication line, determining the capacitance based on the desired value of feed forward equalization to provide to the communication line, providing a layer of resistive material between a first conductor and a second conductor of the communication line, wherein a dimension of the layer of resistive material is determined based on the determined resistance and providing a layer of dielectric material between the first conductor and the second conductor, wherein a dimension of the layer of dielectric material is determined based on the determined capacitance.
    Type: Grant
    Filed: January 22, 2016
    Date of Patent: December 19, 2017
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Thomas W. Liang, Matthew S. Doyle, John R. Dangler, Manuel Orozco, Layne A. Berge
  • Patent number: 9445160
    Abstract: The present invention provides a converter filter that includes a bandstop frequency range to protect against overloading of the input circuits of legacy converter boxes from the relatively high power upstream return path signal between 5 and 85 MHz. The converter filter also functions to pass the downstream signal path with minimal loss and reflection. The converter filter comprises a circuit including a low pass filter and high pass filter in parallel with each other that operate to substantially pass signals in a first frequency band of approximately 5 to 52 MHz and a second frequency band of approximately 85 MHz to 2 GHz while substantially blocking signals in a third frequency band of approximately 52 MHz to 85 MHz.
    Type: Grant
    Filed: June 12, 2015
    Date of Patent: September 13, 2016
    Assignee: Eagle Comtronics, Inc.
    Inventor: Gary John Clark
  • Patent number: 9419680
    Abstract: Series resistance Rs is connected in series between an input terminal 1 and an output terminal 3, and a resonant circuit 11 including an inductor L1 and a capacitor C1, and a resonant circuit 13 including an inductor L3 and a capacitor C3 are connected between the input terminal 1 and the output terminal 3, in parallel to the series resistance Rs. One end of a shunt resistance R1 is connected to a connection point P1 of the inductor L1 and the capacitor C1, and the other end is connected to a ground destination. One end of a shunt resistance R3 is connected to a connection point P3 of the inductor L3 and the capacitor C3, and the other end is connected to the ground destination.
    Type: Grant
    Filed: December 11, 2014
    Date of Patent: August 16, 2016
    Assignee: MATSUE ELMEC CORPORATION
    Inventor: Masaaki Kameya
  • Patent number: 9401688
    Abstract: A first meander line 1A is formed on one surface of a first dielectric layer 9A, with one end as a signal input position, and the other end connected to a first termination resistance 5A, and a second meander line 1C facing the first meander line 1A is formed on a surface facing the first dielectric layer 9A, and the second meander line 1C is formed, with one end positioned at the other end side of the first meander line 1A as a signal output position, and the other end connected to a second termination resistance 5C, and a first conductor line 3A is formed on the side facing the first dielectric layer 9A, with one end connected to the signal input position and the other connected to the signal output position, and a dividing section in a middle of the first conductor line 3A is connected by a first series resistance 7A.
    Type: Grant
    Filed: December 10, 2012
    Date of Patent: July 26, 2016
    Assignee: MATSUE ELMEC CORPORATION
    Inventor: Masaaki Kameya
  • Patent number: 9166564
    Abstract: A wideband bandpass filter includes an RF input terminal, an RF output terminal, a plurality of electrically tunable coupling capacitors coupled in series between the RF input and output terminals, and a plurality of resonating circuits each including an electrically tunable resonator capacitor coupled to one of the coupling capacitors. At least one resistance is coupled in series between at least one of the coupling capacitors for providing enhanced out of band rejection of the filter.
    Type: Grant
    Filed: February 1, 2011
    Date of Patent: October 20, 2015
    Assignee: Hittite Microwave Corporation
    Inventor: Michael Koechlin
  • Patent number: 8896158
    Abstract: A variable capacitance circuit includes: a prescribed node, to which an alternate current signal with a reference potential as a center voltage is applied; a first capacitor connected to the prescribed node; a second capacitor connected between the first capacitor and the reference potential; a third capacitor and a transistor for controlling capacitance, provide between a first node between the second capacitor and the first capacitor, and the reference potential; and a bias circuit which applies a first bias voltage to a second node between the third capacitor and the transistor.
    Type: Grant
    Filed: November 29, 2011
    Date of Patent: November 25, 2014
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Hiroyuki Nakamoto
  • Publication number: 20140022030
    Abstract: An exemplary embodiment of the present disclosure illustrates a signal transmission cell having a first through third conductors, a capacitor and an inductor. The first and third conductors form a first transmission circuit, and the second and the third conductors form a second transmission circuit. Signals which are respectively conveyed on the first transmission circuit and the second transmission circuit have the same magnitude, but have the opposite phases to each other, so as to form a pair of differential transmission lines. A first end of the inductor is electrically connected to the third conductor, and a second end of the inductor is electrically connected to a ground voltage. A first end of the capacitor is electrically connected to the first end of the inductor, and a second end of the capacitor is electrically connected to the second end the inductor.
    Type: Application
    Filed: December 29, 2012
    Publication date: January 23, 2014
    Applicant: NATIONAL TAIWAN UNIVERSITY
    Inventors: TZONG-LIN WU, CHIH-YING HSIAO, CHUNG-HAO TSAI
  • Patent number: 8054154
    Abstract: A planar transformer includes first and second windings that may be comprised of electrically conductive traces etched onto one or more printed circuit boards. The printed circuit boards may be arranged in various orientations so as to change the turns ratio of the planar transformer. In one embodiment, the printed circuit boards are substantially similar and may be electrically connected via connectors that separate the circuit boards. Insulating sleeves may be inserted between the printed circuit boards in an interleaved configuration.
    Type: Grant
    Filed: September 26, 2008
    Date of Patent: November 8, 2011
    Assignee: Linclon Global, Inc.
    Inventors: George Bradley Koprivnak, Thomas David Williams
  • Publication number: 20110227669
    Abstract: A cable emulator configured to emulate the electrical transfer function and properties of a length of conductive cable is disclosed for use in transmitter, receiver and transceiver operation without need for long and expensive length of actual cable. The cable emulator includes an input port for connection to a signal source, such as a transmitter and an output port for connection to a receiver or other signal analyzer. The input port connects to an input impedance matching element, which in turn connects to one or more filter stages. The output of the one or more filter stages connects to an output impedance matching element, which then connects to the output port. The one or more filter stage comprises one or more to resistors, one or more inductors and one or more capacitors.
    Type: Application
    Filed: December 1, 2010
    Publication date: September 22, 2011
    Inventors: Nader Kalantari, Alfredo Moncayo
  • Patent number: 8022575
    Abstract: Exemplary embodiments of the present disclosure provide a method and controller for damping multimode electromagnetic oscillations in electric power systems which interconnect a plurality of generators and consumers. The controller for damping such oscillations includes a phasor measurement unit (PMU) and a power oscillation damper (POD) controller. Each oscillating mode signal is damped and then superposed to derive a control signal. A feedback controller is used to feedback the control signal to a power flow control device in the power system.
    Type: Grant
    Filed: September 16, 2009
    Date of Patent: September 20, 2011
    Assignee: ABB Research Ltd
    Inventors: Petr Korba, Mats Larsson
  • Publication number: 20100188168
    Abstract: Provided is a wide band filter structure including two coupling units and one bridge unit. Each of the coupling units has a joint. The joint is concentrically encircled by a spiral with two ends. One of the ends of the spiral is positioned at the joint. The bridge unit is connected to between the two spirals by the other ends thereof, respectively. The wide band filter structure achieves high impedance, prevents wide band Delta-I noise, improves electromagnetic interference (EMI) and electromagnetic compatibility (EMC), and reduces cost when used in related layout of printed circuit boards and IC package substrates.
    Type: Application
    Filed: January 27, 2009
    Publication date: July 29, 2010
    Inventors: Ding-Bing LIN, Kuo-Chiang HUNG
  • Patent number: 7738610
    Abstract: A method and apparatus are provided for automatic alignment of a notch filter in a receiver. The method comprises the steps of determining a frequency of an interfering signal, monitoring an energy in the interfering signal, tuning the notch filter based on an initial tune value, detecting an energy content in the radio signal after the tuning step, incrementally tuning the notch filter away from the initial tune value while monitoring the energy in the interfering signal, repeating the step of detecting and the step of incrementally tuning until the energy in the interfering signal is minimized, and storing a new tune value as the initial tune value. The notch filter is configured to filter the radio signal. The new tune value indicates a minimized energy in the interfering signal.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: June 15, 2010
    Assignee: Honeywell International Inc.
    Inventors: Seong K. Chan, Jeffery K. Hunter
  • Publication number: 20090015096
    Abstract: An ultrasound system for providing megasonics and ultrasonics to a liquid at different frequencies and/or sweeping frequencies with associated generators, transducers, operations between resonance and anti-resonance, non-resistive output with phase shift, multiple/sweep/single frequency modes, individually controlled sections, gate drive power control, variable inductive compensation for temperature changes, parallel inductor matching, stacked ceramics and non-volatile memory storage of fault, error and failure history.
    Type: Application
    Filed: July 11, 2007
    Publication date: January 15, 2009
    Inventor: William L. Puskas
  • Patent number: 7245186
    Abstract: The present invention discloses a bandpass amplifier having gain and bandpass performance. The bandpass amplifier includes an input match unit for matching the gain of the amplifier and having a first filter response; a first bias unit electrically connected to the input match unit for driving the first terminal of the amplifier and having a first high pass filter response; a gain stage electrically connected to the first bias unit for providing the flat gain of the amplifier; a second bias unit electrically connected to the gain stage for driving the second terminal of the amplifier and having a second high pass filter response; and an output match unit electrically connected to the second bias unit for matching the gain of the amplifier and having a second filter response.
    Type: Grant
    Filed: July 2, 2004
    Date of Patent: July 17, 2007
    Assignees: Integrated System Solution Corp., Sheng-Fuh Chang
    Inventors: Sheng Fuh Chang, Jia Liang Chen, Cherng Cherng Liu, Hung Cheng Chen, Shu Fen Tang, Albert Chen
  • Patent number: 7030717
    Abstract: An impedance matching wave filter includes an original wave filter and a match circuit. The match circuit is connected in parallel with the original wave filter and is able to be varied to produce impedance matching with the original wave filter in order to improve the condition of the return loss and to lower signal fading and signal distortion.
    Type: Grant
    Filed: May 19, 2004
    Date of Patent: April 18, 2006
    Assignee: Soontai Tech Co., Ltd
    Inventor: Shun-Ho Chung
  • Patent number: 6927645
    Abstract: An electronic component and a method of its structuring wherein the component is intended to compensate for “cable loss” attributable to the decay of certain signal characteristics including both frequency and amplitude decay over long distances of coaxial cable of the type utilized in CATV-MATV broadband cable facilities. The method comprises the continuous processing of a signal through a base circuit and monitoring the predetermined signal characteristics including frequency and amplitude. A Circuit modifications are sequentially applied to the base circuit and balanced to approximate stabilization of the signal characteristics until the base circuit and combined plurality of circuit modifications closely approximate signal stabilization.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: August 9, 2005
    Assignee: Broadband International, Inc.
    Inventor: Monte N. Errington
  • Patent number: 6903628
    Abstract: A laminated lowpass filter includes nine dielectric substrates arranged in a stack. The outer surfaces of the stack are ground planes. From top to bottom, top four layers forms a first MIM capacitor, a spiral four-port “mutually coupled coils” (MCCs) structure is placed in the middle, and then the second MIM capacitor is formed on bottom four layers. The first port (P1?) of the MCCs is connected to the first MIM capacitor. The fourth port (P4?) of the MCCs is connected to the second MIM capacitor. The second and third ports (P2?, P3?) constitute input and output of the laminated lowpass filter on the sides of the stack.
    Type: Grant
    Filed: July 18, 2003
    Date of Patent: June 7, 2005
    Assignee: Chi Mei Communication Systems, Inc.
    Inventor: Chien-Chang Liu
  • Patent number: 6876271
    Abstract: An electronic microwave circuit (1) with field effect transistors which are integrated on at least one semiconductor chip (2), has a light source (3), which radiates the field effect transistors with light and possesses a housing (6) which encloses in a microwave excluding manner the semiconductor chip (2) and the light source (3) or a light conducting means (8) connected with the light source (3).
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: April 5, 2005
    Assignee: Rohde & Schwarz GmbH & Co. KG
    Inventors: Christian Evers, Wolfgang Cohrs, Gerd Hechtfischer, Martin Hassler, Thomas Will
  • Patent number: 6788168
    Abstract: A filter is formed as an integrated circuit by resistive and capacitive elements and includes, for connection to ground, at least two separate pads of a chip designed to be connected individually to at least two separate terminals of a package.
    Type: Grant
    Filed: July 29, 2002
    Date of Patent: September 7, 2004
    Assignee: STMicroelectronics S.A.
    Inventors: Fabrice Guitton, Choukri Karoui
  • Publication number: 20030143950
    Abstract: An apparatus and method for filtering a signal in a phase lock loop is disclosed. An typical apparatus for filtering a phase error signal comprises a first filter subcircuit receiving a phase error signal from a phase comparator and filtering the error signal when enabled, a second filter subcircuit receiving the phase error signal from the phase comparator and filtering the error signal when enabled and first and second enable switches which are activated in combination to control filtering of at the error signal. The first filter subcircuit is enabled by activating a first combination of the enable switches and the second filter subcircuit is enabled by activating a second combination of the enable switches. A fast acquisition subcircuit can also be used to temporarily underdampen the filter and improve overall performance of the phase lock loop circuit. The filter can be used to obtain multimode operation in a cellular radio.
    Type: Application
    Filed: January 29, 2002
    Publication date: July 31, 2003
    Inventor: David Maldonado
  • Patent number: 6583684
    Abstract: A method of designing and structuring an electronic component, specifically but not exclusively an equalizer component of the type which is intended to compensate for “cable loss” primarily attributable to the decay of certain signal characteristics including both frequency decay and amplitude decay over long distances of coaxial cable. The coaxial cable is of the type utilized in CATV-MATV broadband cable facilities. The method comprises the continues processing of a signal through a base circuit including circuit components of pre-established resistance and monitoring the predetermined signal characteristics at least including frequency and amplitude.
    Type: Grant
    Filed: August 11, 2000
    Date of Patent: June 24, 2003
    Assignee: Broadband International, Inc.
    Inventor: Monte N. Errington
  • Publication number: 20030001693
    Abstract: The invention concerns a filter produced in integrated circuit by means of resistive (R) and capacitive (C11, C12, C13, C14, C21, C22, C23, C24) elements and comprising, for ground connection, at least two separate bond pads (61-68) of a chip (69) not directly connected between them and designed to be connected individually to at least two separate terminals (71-78) of a housing (70).
    Type: Application
    Filed: July 29, 2002
    Publication date: January 2, 2003
    Inventors: Fabrice Guitton, Choukri Karoui
  • Publication number: 20020180560
    Abstract: A tunable filter (300) includes first (302) and second (304) “bridged-T” resonators. The first (302) and second (304) resonators are capacitively coupled together via bandwidth control/coupling section (306). A biasing section (314) provides the proper biasing and decoupling for the filter (300). Filter (300) provides for low-side injection mode operation, and provides for a very deep zero on the lower side of the passband resulting in excellent selectivity. Filter (300) provides for excellent selectivity while reducing the number of inductors and varactors needed in the filter circuit. A high side injection mode filter (500) similar to filter (300) is also described in the disclosure.
    Type: Application
    Filed: July 8, 2002
    Publication date: December 5, 2002
    Inventor: Gilberto J. Hernandez
  • Patent number: 6476685
    Abstract: A circuit and method for creating an all pass network for equalizing the group delay of a filter. The all pass filter provides an equalization network including a transformer having a primary and secondary winding magnetically coupled together. One end of each primary and secondary winding is connected together to form a connection, the remaining ends of the primary and secondary winding constitute input and output terminals to the equalization network. Control over the group delay response is effected by a bias conductor serially connected to the common ends of the primary and secondary winding and a capacitor connected to the common terminal. The bias conductor modifies the mutual inductance, therefore modifying the coupling factor for the transformer. By shifting control of the coupling to the bias conductor, group delay response may be controlled without further modifications of the transformer coupling.
    Type: Grant
    Filed: March 1, 2000
    Date of Patent: November 5, 2002
    Inventor: William S. H. Cheung
  • Publication number: 20020047757
    Abstract: An integrated RF filter for use at microwave frequencies comprising: an integrated circuit inductor with connected integrated circuit capacitors, arranged as a tank circuit, and an integrated circuit shunt resistor; the inductor, capacitors and resistor being interconnected in a bridge-T filter arrangement.
    Type: Application
    Filed: August 21, 2001
    Publication date: April 25, 2002
    Inventors: Tajinder Manku, Bish Ray
  • Patent number: 6344705
    Abstract: A filter with surface acoustic wave resonators using an equivalent electrical bridge structure to obtain a good form relationship, i.e., a relationship between the filter rejection band and its pass band. Bridge arms advantageously include the paralleling of several resonators, thereby not requiring additional electrical elements as in the background art which provides for the use of series-connected resonators. Particular implantation methods for preparing equivalent structures to paralleling several resonators are also disclosed.
    Type: Grant
    Filed: August 7, 2000
    Date of Patent: February 5, 2002
    Assignee: Thomson-CSF
    Inventors: Marc Solal, Jean Desbois
  • Patent number: 6137379
    Abstract: A universal noise controller is constructed of two windings on a magnetic core with a potentiometer connected across the windings. The input is connected in parallel to the windings and the potentiometer and the output is taken from a node in the center of the windings and a wiper arm of the potentiometer. This arrangement allows a phase change of 360 degrees by overlaying another signal thus providing phase cancellation from positive 180 degrees to negative 180 degrees thereby providing suitable noise cancellation based on the position of the wiper arm.
    Type: Grant
    Filed: September 23, 1996
    Date of Patent: October 24, 2000
    Inventor: Russell C. Morrill
  • Patent number: 5724387
    Abstract: A cable loss simulator for a serial digital signal source adapts a constant resistance, bridged-T passive network to simulate the frequency-loss characteristics of a reference coaxial cable. The cable loss simulator is selectively coupled into the output path of the serial digital signal source to simulate the serial digital signal after transmission through the reference coaxial cable. The cable loss simulator has a resistive input section for impedance matching with the serial digital signal source and a bridged-T section with multiple breakpoints to simulate the frequency-loss characteristic of the reference coaxial cable.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: March 3, 1998
    Assignee: Tektronix, Inc.
    Inventors: Daniel G. Baker, Michael Harris
  • Patent number: 5576756
    Abstract: An electrical network emulates the transmission characteristics of a video signal cable, allowing tests to be made as to the length to which the cable may be extended before video signal degradation occurs. The preferred embodiment emulates a Beldon.RTM. 8281 coaxial cable, used for the transmission of serial digital video signals, and comprises four sections. The sections are arranged to emulate cable lengths of 25 meters, 50 meters and 200 meters.
    Type: Grant
    Filed: January 13, 1994
    Date of Patent: November 19, 1996
    Assignee: Faraday Technology Limited
    Inventors: David C. Baty, Barry D. R. Miles
  • Patent number: 5396197
    Abstract: A transformer-coupled, bridged-T network for connection of a load to an electrical communication network includes a transformer with a center tap and two end taps, a drop cable for electrical connection of the load to the center tap and passive elements connected across the transformer to compensate for impedance of the drop cable and the load when the load is connected through the drop cable to the center tap
    Type: Grant
    Filed: June 24, 1994
    Date of Patent: March 7, 1995
    Assignee: Allen-Bradley Company, Inc.
    Inventors: Lawrence W. Esker, Fred P. Rhine
  • Patent number: 5202651
    Abstract: An image band-stop filter circuit includes a transmission line formed on a substrate of GaAs and a T circuit connected in parallel to the transmission line and having a high pass filter characteristic. The T circuit includes series-connected first and second capacitances connected in parallel to the transmission line and a stub having one end connected to a node between the first and second capacitances and the other end short-circuited. The stub has a line length which becomes inductive in an image signal band to be removed. As a result, the lengths of the transmission line and the stub can be reduced to enable the band-stop filter circuit to be made into a MMIC with ease while achieving an excellent signal transmission characteristic.
    Type: Grant
    Filed: December 24, 1991
    Date of Patent: April 13, 1993
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Toshihiko Yoshimasu
  • Patent number: 5187457
    Abstract: A harmonic and subharmonic filter is coupled between a high power RF energy source and a non-linear RF load via a matching network, such as a plasma chamber. The filter passes high power RF energy in a band centered on a predetermined radio frequency, i.e., 13.56 MHz, but blocks and attenuates out-of-band energy at frequencies which are multiples of or fractions of the predetermined frequency. The harmonic and subharmonic filter comprises an input terminal, an output terminal, a series LC resonance path connected between the input and output terminals, and tuned to the predetermined radio frequency, a series resistive path formed of first and second resistors, and a parallel LC resonance path between the junction of the two resistors and ground.
    Type: Grant
    Filed: September 12, 1991
    Date of Patent: February 16, 1993
    Assignee: Eni Div. of Astec America, Inc.
    Inventors: Yogendra K. Chawla, Steven J. Smith
  • Patent number: 5157362
    Abstract: A notch filter having increased pass band characteristics is provided by insertion of an inductor between a normally-grounded capacitor and ground, the capacitor being connected to an inductive-capacitive filter network. By this construction, the equivalent capacitor of the high-frequency equivalent circuit is not connected directly to ground, but rather has the inductor interposed between it and ground. This significantly increases the pass band of the circuit.
    Type: Grant
    Filed: March 27, 1990
    Date of Patent: October 20, 1992
    Assignee: Andrew F. Tresness
    Inventor: Martin L. Zelenz
  • Patent number: 5121078
    Abstract: A filtering cell including a resonant circuit having an inductor and capacitor connected in parallel, the inductor being separated into two identical inductors which are connected in series with a midpoint therebetween. A second capacitor is connected at the midpoint and has a quality factor substantially equal to a quality factor of the first inductor, resulting in attenuation at the resonant frequency. Each of the inductors and capacitors are formed by micro-ribbon technology.
    Type: Grant
    Filed: October 18, 1990
    Date of Patent: June 9, 1992
    Assignees: French State Represented by the Minister of Post, Telecommunications and Space (Centre National D'Etudes Des Telecommunications), Telediffusion de France
    Inventors: Henri Havot, Yvon Dutertre
  • Patent number: 5028895
    Abstract: A notch filter for reducing clock signal feedthrough effects in an acoustic charge transport (ACT) device. This notch filter is included on the same substrate as an ACT device. This notch filter may be employed to remove clock signals which have greater voltage than the data signals in an ACT device. This notch filter may be employed either at the input or the output of the ACT device. The notch filter includes a bridge connection of surface acoustic wave transducers and RC networks on opposite sides of the bridge configuration. Each side of the bridge is balanced so that at the notch filter frequency, the voltage output by each side of the bridge is one-half of the input voltage and in phase. These voltages produced by each half of the bridge are differenced and a zero output voltage is produced at approximately a notch or center frequency.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: July 2, 1991
    Assignee: Motorola, Inc.
    Inventor: Frederick M. Fliegel
  • Patent number: 4945321
    Abstract: In a .pi./2 power divider, particularly a .pi./2 hybrid for the radio-frequency antenna of a nuclear magnetic resonance tomography apparatus, a decoupling circuit having unbalanced-to-ground line transformers is provided. Each branch thereof contains an all pass network consisting unbalanced-to-ground line transformers at the output. A broadband .pi./2 hybrid is obtained particularly with a broadband 3 dB/180.degree. hybrid as the decoupling circuit.
    Type: Grant
    Filed: April 5, 1989
    Date of Patent: July 31, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventors: Ralph Oppelt, Markus Vester
  • Patent number: 4885562
    Abstract: According to the invention, the circuit comprises at least one two-port network of the "M-derived" section type and connected as an all-pass filter with a phase law which is a linear function of frequency. The two-port network is made in monolithic technology on gallium arsenide and the plane of its structure includes at least one elementary section, which, between an inlet and an outlet which are situated at a distance apart, is constituted by a spiral connected in parallel with a capacitor of metal-insulator-metal structure, with the mid point of the spiral being connected via another capacitor of metal-insulator metal structure to a ground plane. It is applicable to making transmission lines which are programamble in length.
    Type: Grant
    Filed: December 9, 1987
    Date of Patent: December 5, 1989
    Assignee: Electronique Serge Dassault
    Inventors: Pierre-Louis Ouvrard, Philippe Dueme
  • Patent number: 4795990
    Abstract: In a bridge T type trap circuit having CR delta connection circuit and a variable LC tank circuit, the CR delta connection circuit is connected to the LC tank circuit via a variable inductor (19; 31, 33; 40). In one embodiment, a capacitor (18) is coupled with the variable inductor (19; 31, 33) to form another LC tank circuit. In another embodiment, a variable inductor (39) used in the first-mentioned LC tank circuit has a tap which is grounded. Impedance values of the first-mentioned LC tank circuit and the variable inductor (40) are adjusted so that absolute values of real and imaginary parts thereof have a given relationship. A resistor (22) of the CR delta connection circuit is used in common in a double-trap structure having two CR delta connection circuits and two series circuits each having two LC tank circuits.
    Type: Grant
    Filed: April 17, 1986
    Date of Patent: January 3, 1989
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takayoshi Ishikawa, Yasuhiko Yoshida
  • Patent number: 4635005
    Abstract: The invention relates to a quadrupole for resistive matching of a reactance of the RLC type connected in series or in parallel, which permits to compensate for the loss of gain of an amplifier as the frequency rises, in a manner independent of the frequency. This quadrupole comprises two impedance circuits Z.sub.1 and Z.sub.2 in series between an input terminal and an output terminal, and in parallel with these, a third impedance circuit Z.sub.3. It also comprises a fourth impedance circuit Z.sub.4 connected between the point common to the first two circuits Z.sub.1, Z.sub.2 and the point common to the two other terminals of the quadrupole. The reactance which is to be matched is Z.sub.3 if it is of the RLC type connected in parallel. It is Z.sub.4 if it is of the RLC type connected in series. The values of the three other impedances Z.sub.1, Z.sub.2 and Z.sub.4 or Z.sub.3 are related so that the input impedance may be equal to the output impedance.
    Type: Grant
    Filed: July 9, 1984
    Date of Patent: January 6, 1987
    Assignee: Thomson-CSF
    Inventor: Didier Kaminsky
  • Patent number: 4577168
    Abstract: An improved notch filter having a single port, surface acoustic wave transducer in parallel with an inductor and forming a first circuit which primarily blocks the signal frequency at all frequencies except the notch frequency at which point the first circuit becomes essentially resistive and at that point is cancelled by a signal from a second circuit in parallel with said first circuit and which is 180.degree. out-of-phase thereby providing a notch filter.
    Type: Grant
    Filed: December 3, 1984
    Date of Patent: March 18, 1986
    Assignee: R. F. Monolithics, Inc.
    Inventor: Clinton S. Hartmann
  • Patent number: 4454487
    Abstract: The odd order auto-corrected electric filter comprises first input matching means for receiving the input signal and transmitting it to filter means for bringing about a broad band filtering of the signal and transmitting it to second output matching means. Correction means placed between at least two filter members bring about a self-correction of the envelope delay and/or an amplitude correction.
    Type: Grant
    Filed: March 19, 1982
    Date of Patent: June 12, 1984
    Assignee: Thomson-CSF
    Inventor: Corinne Darmouni
  • Patent number: 4443772
    Abstract: A microwave group delay equalizer in microstrip form comprises a dielectric substrate having a ground plane on one surface and on the other surface two conductive strips oriented end to end and spaced apart by a narrow gap and connected together by a relatively narrow inductive conductive strip of substantially greater length than the gap between the first two strips. A dielectric layer overlies the adjacent ends of the first two conductor strips. A fourth conductor strip is disposed over the dielectric layer to provide capacitive coupling between the first and second conductors. The fourth conductor is connected to a grounded capacitor by a fifth relatively narrow inductive conductive strip.
    Type: Grant
    Filed: December 10, 1981
    Date of Patent: April 17, 1984
    Assignee: RCA Corporation
    Inventor: Alfred Schwarzmann