Wave Filter Patents (Class 331/77)
  • Patent number: 9525302
    Abstract: As an aspect of the present invention, a noncontact power feeding apparatus includes: a power transmission resonator; and a power reception resonator configured to be magnetically coupled with the power transmission resonator by magnetic field resonance. The power transmission resonator is magnetically coupled with the power reception resonator by the magnetic field resonance, whereby electric power is supplied from an electric power source to the power reception resonator through the power transmission resonator. One of the power transmission resonator and the power reception resonator has a predetermined single resonant frequency, and the other one of the power transmission resonator and the power reception resonator has multiple resonant frequencies inclusive of the predetermined single resonant frequency.
    Type: Grant
    Filed: March 7, 2011
    Date of Patent: December 20, 2016
    Assignee: NISSAN MOTOR CO., LTD.
    Inventors: Kraisorn Throngnumchai, Toshihiro Kai, Yusuke Minagawa
  • Patent number: 9312051
    Abstract: The invention is a coaxial conductor structure for fault-free transmission of a TEM Mode of a HF signal wave within at least one band of frequency bands forming in the context of a dispersion relation. An inner conductor and an outer conductor are spaced radially apart from the inner conductor and an axially extending common conductor section of the inner and the outer conductor. A number n of electrically conductive ring-shaped structures are each fitted between the inner and outer conductor to be radially spaced apart, each of which have an electrical path completely surrounding the inner conductor and are arranged with a spatially periodic sequence with an equal distance between the two ring-shaped structures which are adjacent along the conductor section.
    Type: Grant
    Filed: July 11, 2011
    Date of Patent: April 12, 2016
    Assignee: Spinner GmbH
    Inventors: Martin Lorenz, Kai Numssen, Christoph Neumaier, Natalie Spaeth
  • Patent number: 8686800
    Abstract: A system for generating a frequency reference signal comprising an oscillator, a direct digital synthesizer coupled to the oscillator and configured to receive a signal output from the oscillator, a digital to analog converter coupled to the direct digital synthesizer and configured to receive a sampled signal from the direct digital synthesizer and to convert the sampled signal to an analog waveform, and a bandpass filter coupled to the digital to analog converter and configured to select an aliased output signal from the digital to analog converter at a Nyquist zone other than a first Nyquist zone and to output the frequency reference signal.
    Type: Grant
    Filed: November 13, 2012
    Date of Patent: April 1, 2014
    Assignee: Comtech EF Data Corp.
    Inventors: Cris Mamaril, Tiberiu Artzi, Terry Richmond
  • Patent number: 8310315
    Abstract: A system for generating a frequency reference signal comprising an oscillator, a direct digital synthesizer coupled to the oscillator and configured to receive a signal output from the oscillator, a digital to analog converter coupled to the direct digital synthesizer and configured to receive a sampled signal from the direct digital synthesizer and to convert the sampled signal to an analog waveform, and a bandpass filter coupled to the digital to analog converter and configured to select an aliased output signal from the digital to analog converter at a Nyquist zone other than a first Nyquist zone and to output the frequency reference signal.
    Type: Grant
    Filed: September 9, 2010
    Date of Patent: November 13, 2012
    Assignee: Comtech EF Data Corp.
    Inventors: Chris Mamaril, Tiberiu Artzi, Terry Richmond
  • Patent number: 8183941
    Abstract: An electronic device (ED) is intended for generating a local oscillator signal having a chosen frequency FLO from a main signal outputted by a voltage-controlled oscillator (VCO) and having a fundamental frequency FVCO and harmonics thereof. This electronic device (ED) comprises a frequency division means (D1, D2) arranged to divide the frequency of a signal by a chosen factor N and a filter means (F1, F2) arranged to select a chosen Mth order harmonic of a signal, these frequency division means (D1, D2; D) and filter means (F1, F2) being arranged to process the main signal in common to output the local oscillator signal with a chosen frequency FLO equal to MxFVCO/N.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: May 22, 2012
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Dominique Delbecq, Michel Germe
  • Patent number: 8160518
    Abstract: A transceiver includes a harmonic termination circuit that receives a tunable harmonic voltage from a power amplifier control. The harmonic termination circuit includes a variable capacitor that is capable of adjusting its capacitance in response to the tunable harmonic termination voltage to achieve at least two modes of operation. The at least two modes of operation may be EDGE mode and GSM mode. In this embodiment, the harmonic termination circuit allows for linearity specifications of EDGE to be met, while not degrading the efficiency of the transceiver when operating in GSM mode. In one embodiment, the harmonic termination circuit further includes an inductive element in series with the variable capacitor.
    Type: Grant
    Filed: August 3, 2007
    Date of Patent: April 17, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Marcus R. Ray, Darrell G. Hill, Ricardo A. Uscola
  • Patent number: 7924106
    Abstract: To provide an oscillation module which is able to improve an input level by passing signals in a main signal band while removing near noise and far noise. An oscillation module is provided with an OCXO, an amplifier, and a noise elimination filter. The noise elimination filter includes: a BPF passing a signal in the main signal band and eliminating far noise with respect to the main signal band; an L-BEF eliminating near noise in a low frequency band with respect to the main signal band; and an H-BEF eliminating near noise in a high frequency band with respect to the main signal band. Each filter is configured with a crystal filter.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: April 12, 2011
    Assignee: Nihon Dempa Kogyo Co., Ltd
    Inventors: Naoto Inouchi, Kazuo Akaike, Junichiro Yamakawa, Masazumi Kubota
  • Patent number: 7847646
    Abstract: A carrier generator for generating a carrier at a frequency of interest in a wireless communications system comprises an oscillator exhibiting a first impedance, the oscillator comprising an energy storage tank configured to generate a periodic signal, the energy storage tank including at least one inductor and at least one capacitor, and an amplifier coupled with the energy storage tank, the amplifier being configured to amplify an amplitude of the periodic signal, an antenna exhibiting a second impedance smaller than the first impedance, and a network coupled between the oscillator and the antenna, the network including at least one inductor or at least one capacitor and being configured to provide a third impedance such that a resultant impedance of the second impedance and the third impedance as viewed from the oscillator toward the antenna is large enough to facilitate the oscillator to generate the carrier at the frequency of interest.
    Type: Grant
    Filed: May 27, 2008
    Date of Patent: December 7, 2010
    Assignee: FAVEPC, Inc.
    Inventors: Chun-Liang Tsai, Shao-Chang Chang
  • Patent number: 7598817
    Abstract: An oscillator includes: oscillation units (11 through 1n) outputting oscillation signals of different frequencies; a transmission line (15) to which outputs of the oscillation units (11, 12) are connected, the transmission line having a characteristic impedance corresponding to an output impedance of an output terminal (Tout); and a low-pass filter 818) connected between the transmission line (15) and the output terminal.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: October 6, 2009
    Assignee: Fujitsu Media Devices Limited
    Inventors: Toshimasa Numata, Alejandro Puel
  • Patent number: 7576619
    Abstract: An integrated circuit arrangement is disclosed. In one embodiment, the integrated circuit arrangement includes an output circuit having at least one first output connection which can provide a data signal, at least one first data output connection; and at least one first inductance connected between the at least one first output connection and the at least one data output connection.
    Type: Grant
    Filed: July 11, 2003
    Date of Patent: August 18, 2009
    Assignee: Infineon Technologies AG
    Inventors: Daniel Kehrer, Herbert Knapp
  • Publication number: 20090174488
    Abstract: To provide an oscillation module which is able to improve an input level by passing signals in a main signal band while removing near noise and far noise. An oscillation module is provided with an OCXO, an amplifier, and a noise elimination filter. The noise elimination filter includes: a BPF passing a signal in the main signal band and eliminating far noise with respect to the main signal band; an L-BEF eliminating near noise in a low frequency band with respect to the main signal band; and an H-BEF eliminating near noise in a high frequency band with respect to the main signal band. Each filter is configured with a crystal filter.
    Type: Application
    Filed: December 23, 2008
    Publication date: July 9, 2009
    Inventors: Naoto Inouchi, Kazuo Akaike, Junichiro Yamakawa, Masazumi Kubota
  • Patent number: 7539465
    Abstract: A reader for an RFID system includes a signal driver for generating an excitation signal and a resonant circuit having an adjustable resonant circuit capacitance for retuning the resonant circuit in response to detuning. The resonant circuit has a capacitance tuning circuit which includes a fine-tuning capacitor having a fine-tuning capacitance and a fine-tuning capacitor switch having an open position and a closed position. The fine-tuning capacitance is added to the adjustable resonant circuit capacitance when the fine-tuning capacitor switch is in the closed position and is removed from the adjustable resonant circuit capacitance when the fine-tuning capacitor switch is in the open position.
    Type: Grant
    Filed: October 16, 2006
    Date of Patent: May 26, 2009
    Assignee: Assa Abloy AB
    Inventor: Ralph W. Quan
  • Patent number: 7498893
    Abstract: An oscillator circuit for generating a high-frequency electromagnetic oscillation, comprises:—an amplifier configuration with at least one input and at least one output,—an oscillator crystal connected to at least one of the outputs of the amplifier configuration,—a bandpass filter configuration, which is connected, with at least one input, to the oscillator crystal and the at least one output of the amplifier configuration connected to the oscillator crystal, and back coupled, with at least one output, to the input, or at least one of the inputs, of the amplifier configuration.
    Type: Grant
    Filed: December 4, 2003
    Date of Patent: March 3, 2009
    Assignee: NXP B.V.
    Inventor: Andreas Koellmann
  • Patent number: 7432770
    Abstract: The present invention provides a signal transmission device in which jitter occurring in a clock signal is eliminated. The signal transmission device has a construction in which a transmission end IC chip provided with a transmission part of a data signal and a reception end IC chip provided with a reception part of the data signal, the transmission part and the reception part are connected via a data signal transmission line, an oscillator that outputs a clock signal to the transmission part is connected with the transmission end IC chip, a clock signal transmission line is provided which leads the clock signal output from the oscillator to the reception part, and a SAW filter is arranged in the clock signal transmission line.
    Type: Grant
    Filed: August 8, 2006
    Date of Patent: October 7, 2008
    Assignee: Seiko Epson Corporation
    Inventors: Mikio Shigemori, Masataka Nomura
  • Patent number: 7397314
    Abstract: A redundant clock source provides a stable clock source for digital system. The clock source uses two oscillators to generate a clock signal. If one of the oscillators fails, the clock signal is generated from the other oscillator until the failed oscillator is replaced. Special filtering of the waveforms produced by the oscillators makes the clock source is resistant to jitter from the oscillators and transients that occur when an oscillator fails. This allows the clock source to not only use a redundant oscillator in an attempt to eliminate a single point of failure, but to also provide a stable clock signal even if one oscillator fails.
    Type: Grant
    Filed: September 11, 2002
    Date of Patent: July 8, 2008
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Daniel Wissell
  • Publication number: 20080157886
    Abstract: An oscillator includes: oscillation units (11 through 1n) outputting oscillation signals of different frequencies; a transmission line (15) to which outputs of the oscillation units (11, 12) are connected, the transmission line having a characteristic impedance corresponding to an output impedance of an output terminal (Tout); and a low-pass filter 818) connected between the transmission line (15) and the output terminal.
    Type: Application
    Filed: December 27, 2006
    Publication date: July 3, 2008
    Inventors: Toshimasa Numata, Alejandro Puel
  • Patent number: 7362190
    Abstract: An integrated circuit has an internal oscillator circuit for being connected to an external frequency source such as a crystal or a ceramic resonator. The internal oscillator circuit has an inverting amplifier across the frequency source terminals to establish an oscillation there. One terminal of the frequency source is coupled to one input of the comparator and to a second input of the comparator through a low pass filter. Coupling the output of the low pass filter to the second input of the comparator is for preventing a DC offset from developing between the two inputs of the comparator. The other terminal of the frequency source is coupled to the second input of the comparator through a high pass filter. The high pass filter provides the comparator with a larger voltage differential to increase noise margin. Noise margin is further improved by allowing an increase in hysteresis in the comparator.
    Type: Grant
    Filed: December 9, 2005
    Date of Patent: April 22, 2008
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Michael T. Berens, James R. Feddeler
  • Patent number: 7355484
    Abstract: An oscillator and a radar apparatus that includes a resonator electro-magnetically connected to a micro strip line and a rotor connected to the resonator by capacitance. The bottom surface of the rotor has a changing height in the circumferential direction of the rotor. As the rotor is rotated, an actual oscillation frequency is recognized from the rotating angle of the rotor when an output of a detector has a peak. A modulation voltage supplied to a VCO is corrected in accordance with the result.
    Type: Grant
    Filed: October 19, 2004
    Date of Patent: April 8, 2008
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Takatoshi Kato, Toru Ishii
  • Patent number: 7345549
    Abstract: A phase-locked loop (200) includes a sampler (202), a phase detector (210), a loop filter (212), and a VCO (214). The loop achieves frequency multiplication without the need for a divider in the loop's feedback path. The VCO (214) is operated above the Nyquist rate of the sampler, causing the loop to lock on an aliased signal. Any variations in the VCO output frequency (i.e., jitter or phase noise) are fed back to the phase detector (210) 1-for-1, without attenuation normally associated with frequency dividers. Loop gain can therefore be kept high, even in loops that provide high closed loop frequency multiplication. According to one variation, a harmonic generator (540) is placed between the VCO and the sampler, thus causing the loop to lock on harmonics of the VCO frequency. Open loop gain and precision are thus further improved.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: March 18, 2008
    Assignee: Teradyne, Inc.
    Inventor: Fang Xu
  • Patent number: 7298217
    Abstract: A phase shifter is fed an input signal having a frequency f. A coupler is included fed by the input signal. The coupler has a pair of output terminals for providing a pair of signals having the frequency f and having a relative phase shift difference of m?/2 radians, where m is an integer. A switch is included having a pair of inputs, each one of the pair of inputs being coupled to a corresponding one of the pair of output terminals of the coupler. The switch has an output, one of the pair of inputs of the switch being coupled to the output of the switch selectively in accordance with a first control signal fed to the switch.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: November 20, 2007
    Assignee: Raytheon Company
    Inventors: Michael G Adlerstein, Valery S. Kaper
  • Patent number: 7277683
    Abstract: The present invention relates generally to communications, and more specifically to a method and apparatus for generating local oscillator signals used for up- and down-conversion of RF (radio frequency) signals. A major problem in the design of modulators and demodulators, if the leakage of local oscillator (LO) signals into the received signal path. The invention presents a number of highly integratable circuits which resolve the LO leakage problem, using regenerative divider circuits acting on oscillator signals which are running at a multiple or fraction of the frequency of the desired LO signal, to generate in-phase (I) and quadrature (Q) mixing signals. Embodiments of these circuits also use harmonic subtraction and polyphase mixers, as well as virtual local oscillator TM (VLO) mixing signals. VLO mixing signals are signal pairs which emulate local oscillator signals by means of complementary mono-tonal and multi-tonal mixing signals.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: October 2, 2007
    Assignee: Sirific Wireless Corporation
    Inventors: Sathwant Dosanjh, William Kung, Tajinder Manku
  • Patent number: 7132899
    Abstract: A method and apparatus for providing a high speed buffer with high gain bandwidth and rail-to-rail operation is disclosed. Resistor-capacitor (RC) filters are added in current mirrors that are in the signal path. The effect of these filters is to create a frequency-dependent impedance that extends the gain bandwidth of the circuit.
    Type: Grant
    Filed: October 22, 2004
    Date of Patent: November 7, 2006
    Assignee: Xilinx, Inc.
    Inventors: Michael J. Gaboury, Matthew L. Bibee
  • Patent number: 6987423
    Abstract: A voltage controlled oscillator (VCO) for use in a personal area network synthesizer includes a delay cell (100), a first current amplifier (201, 203) for amplifying an input current, a resister capacitor (RC) tuning network (207, 209, 211) for varying the amount of amplification and delay of an output of the first current amplifier. A second current amplifier (213, 215) is then used for amplifying an output current from the RC tuning network. The invention includes a unique composite voltage variable capacitor (CVVC) (300) for precisely tuning the amount of delay presented by the delay cell. The unique topology of the delay cell (100) allows it to be readily used in voltage controlled oscillators (VCOs) operable at frequencies above 1 GHz.
    Type: Grant
    Filed: August 19, 2003
    Date of Patent: January 17, 2006
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Daniel E. Brueske, David B. Harnishfeger, Stephen T. Machan
  • Patent number: 6844763
    Abstract: A wideband impedance attenuator includes a phase-locked loop filter, a voltage-controlled oscillator connected to the phase-locked loop filter during transmit, and an impedance circuit connected to the phase-locked loop filter and the voltage controlled oscillator. The impedance circuit is a scaled version of the phase-locked loop filter. Moreover, the wideband impedance attenuator attenuates a Gaussian frequency shift key modulation signal by a factor of 1/(N+1) using the impedance circuit, which has an impedance of N*Z(s), and the phase-locked loop filter, which has an impedance of Z(s). An output frequency is generated using a voltage-controlled oscillator wherein the output frequency corresponds to the attenuated Gaussian frequency shift key modulation signal. In addition, a comparator compares a voltage of an output from the programmable gain amplifier with a voltage necessary to produce a predetermined frequency shift in a voltage-controlled oscillator to produce a gain signal.
    Type: Grant
    Filed: August 29, 2002
    Date of Patent: January 18, 2005
    Assignee: Analog Devices, Inc.
    Inventor: Edmund J. Balboni
  • Patent number: 6762651
    Abstract: A high frequency oscillator according to the present invention is structured in a small size and prevents noise from taking place in a severe environment of which there is a large temperature change. In the high frequency oscillator according to the present invention, the levels of higher harmonic components are increased against the level of a fundamental wave of an oscillating circuit using a quartz-crystal element. Any component of the higher harmonic components is selected by a surface acoustic wave filter having a piezo-electric substrate that is a crystal substrate. The selected component is amplified and a high frequency oscillation output signal is obtained.
    Type: Grant
    Filed: February 7, 2002
    Date of Patent: July 13, 2004
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Takeo Oita
  • Patent number: 6756863
    Abstract: An oscillator of frequency switching type according to the present invention is adapted to select and output any of a plurality of high frequencies. The oscillator of frequency switching type includes a plurality of crystal oscillators whose fundamental frequencies are different, and filters a signal output from the operating crystal oscillator with a SAW filter configured by forming a plurality of IDTs, which set passbands of different frequencies, on the same piezoelectric substrate, or with a filter arranged for each frequency of the corresponding crystal oscillator.
    Type: Grant
    Filed: May 7, 2002
    Date of Patent: June 29, 2004
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventor: Takeo Oita
  • Patent number: 6549083
    Abstract: A high-frequency crystal oscillator capable of outputting a signal at a frequency, for example, higher than 500 MHz without using a multiplication amplifier. The high-frequency crystal oscillator comprises a voltage controlled Colpitts oscillation circuit operating at the fundamental frequency of a quartz-crystal element, means for increasing the level of harmonic component in an output from the Colpitts oscillation circuit, an SAW (Surface Acoustic Wave) filter for selecting a component of a predetermined order of the harmonic component, and a broadband amplifier for amplifying the component selected by the SAW filter. The means for increasing the levels of harmonic component is, for example, a resistor for setting the operating point of a transistor in the oscillation circuit such that an output signal is distorted.
    Type: Grant
    Filed: May 16, 2001
    Date of Patent: April 15, 2003
    Assignee: Nihon Dempa Kogyo Co., Ltd.
    Inventors: Nobuyuki Kanazawa, Takeo Oita, Yuichi Sato
  • Patent number: 6498538
    Abstract: System and method for providing low noise signal having a broad tuning range (1 GHz to 10 GHz, or larger), with associated jitter no more than about 10 percent of the selected period of a target output signal. In a first stage, a ring-based VCO phase locked loop system provides a broad tuning range with some associated noise, and a second stage in a first state is relatively transparent, with no substantial differential attenuation based on frequency. After phase lock is achieved, the second stage is switched to a second state with low associated noise and high differential attenuation based on input signal frequency.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: December 24, 2002
    Assignee: Lattice Semiconductor Corporation
    Inventors: Ming Qu, Ji Zhao
  • Patent number: 6459341
    Abstract: A voltage controlled oscillation device includes a voltage controlled oscillator, fixed-frequency oscillator, frequency mixer, and frequency selector. The voltage controlled oscillator changes the output signal frequency in the microwave band in accordance with the input voltage of a frequency control signal. The fixed-frequency oscillator has a fixed oscillation frequency higher than that of the voltage controlled oscillator. The frequency mixer mixes the output signal from the fixed-frequency oscillator and the output signal from the voltage controlled oscillator and outputs the sum frequency and difference frequency between the two signals. The frequency selector selects and outputs one of the sum frequency and difference frequency contained in the output signal from the frequency mixer.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: October 1, 2002
    Assignee: NEC Corporation
    Inventor: Toshiyuki Oga
  • Publication number: 20020075087
    Abstract: A voltage-controlled oscillator circuit includes a ring oscillator circuit for generating a signal having a series of pulses. The signal with the series of pulses is ac coupled to a filter circuit which converts the series of pulses into a substantially sinusoidal signal which is substantially symmetrical about the reference potential of the system. The sinusoidal signal is applied to an amplifier which converts the sinusoidal signal into a square wave. Because the square wave is generated as an amplified sine wave, it exhibits a high degree of symmetry, i.e., it has a highly accurate 50-50 duty cycle, which makes it applicable in demanding settings such as serving as a clock signal in a high-speed microprocessor system in which both rising and falling edges of the clock signal are used to synchronize events.
    Type: Application
    Filed: December 18, 2000
    Publication date: June 20, 2002
    Applicant: Alpha Processor, Inc.
    Inventor: Gerald Talbot
  • Patent number: 6356143
    Abstract: A variable bandpass filter system passes a selected range of frequencies while rejecting other frequencies in an RF input signal. The system includes a switch and an oscillator. The switch receives the RF input signal and an oscillating calibration signal, and passes the RF input signal or said oscillating calibration signal based on a control signal. The oscillator receives an output of the switch, and frequency and gain control signals. The frequency control signal selects an operating frequency of the oscillator, such that the operating frequency determines a range of frequencies to pass. The gain control signal selects gain of the oscillator, where the oscillating calibration signal allows the oscillator to be calibrated by varying the gain such that the oscillator acts as a filter.
    Type: Grant
    Filed: November 1, 1999
    Date of Patent: March 12, 2002
    Assignee: Intreon Corporation
    Inventor: Steven B. Waltman
  • Patent number: 6348842
    Abstract: An apparatus and method for achieving accurate temperature-invariant sampling frequencies in a device, such as, a multiple message non-volatile multilevel analog signal recording and playback system is described. An oscillator is used to generate an oscillation frequency. A bandgap voltage generator generates a zero temperature coefficient voltage reference (V(OTC)) that is independent of temperature. This V(OTC) is applied to the oscillator. A variable temperature coefficient voltage (V(TC)) that compensates for temperature coefficient variations of a resistor to which V(TC) is applied produces a stable oscillator current Iosc. Therefore, the stable oscillator current Iosc is likewise independent of the temperature coefficient variations of the resistor. The stable oscillator current Iosc is applied to the oscillator such that the oscillator generates a stable temperature-invariant oscillation frequency.
    Type: Grant
    Filed: October 25, 2000
    Date of Patent: February 19, 2002
    Assignee: Winbond Electronics Corporation
    Inventors: Aditya Raina, Peter J. Holzmann, Geoffrey B. Jackson, Saleel V. Awsare
  • Publication number: 20020017959
    Abstract: A high-frequency crystal oscillator capable of outputting a signal at a frequency, for example, higher than 500 MHz without using a multiplication amplifier. The high-frequency crystal oscillator comprises a voltage controlled Colpitts oscillation circuit operating at the fundamental frequency of a quartz-crystal element, means for increasing the level of harmonic component in an output from the Colpitts oscillation circuit, an SAW (Surface Acoustic Wave) filter for selecting a component of a predetermined order of the harmonic component, and a broadband amplifier for amplifying the component selected by the SAW filter. The means for increasing the levels of harmonic component is, for example, a resistor for setting the operating point of a transistor in the oscillation circuit such that an output signal is distorted.
    Type: Application
    Filed: May 16, 2001
    Publication date: February 14, 2002
    Applicant: NIHON DEMPA KOGYO CO., LTD
    Inventors: Nobuyuki Kanazawa, Takeo Oita, Yuichi Sato
  • Publication number: 20010035794
    Abstract: An oscillator includes an oscillating circuit and a resonating circuit connected to the oscillating circuit, and an amplifying circuit for amplifying signals output from the oscillating circuit. The oscillator also includes an added circuit having an isolator, frequency filter, or other suitable elements, disposed between the output portion of the oscillating circuit and the input portion of the amplifying circuit, so as to prevent transmission of unwanted waves, such as the higher harmonic component of the basic wave, and other such undesirable waves. The oscillator, and a communication apparatus including such oscillator, eliminates deterioration of phase noise properties caused by generation of unwanted wave components such as higher harmonics.
    Type: Application
    Filed: April 27, 2001
    Publication date: November 1, 2001
    Applicant: Murata Manufacturing Co., Ltd.
    Inventors: Masanori Fujidai, Fumitoshi Sato, Toshio Hata
  • Patent number: 6292063
    Abstract: The two-band oscillating apparatus of the present invention comprises in one aspect a first oscillator for outputting an oscillation signal of a first frequency band, a second oscillator for outputting an oscillation signal of a second frequency band which is higher than the first frequency band, and a grounded-emitter type amplifier including an amplifying transistor to amplify the oscillation signal of the first frequency band or the oscillation signal of the second frequency band. In this structure, an emitter bias resistor is connected between the emitter of the amplifying transistor and the ground. A first series resonance device which resonates in almost the first frequency band, and a second series resonance device which resonates in almost second frequency band, are connected between the emitter and ground. Thereby, the number of parts can be reduced through simplified structure.
    Type: Grant
    Filed: August 8, 2000
    Date of Patent: September 18, 2001
    Assignee: Alps Electric Co., Ltd.
    Inventors: Takeshi Tanemura, Yasuhiro Ikarashi
  • Patent number: 6288615
    Abstract: A switch-type oscillating circuit includes a first oscillating circuit for outputting an oscillation signal having a first frequency, which includes a first oscillation transistor and a first switch circuit for turning on and off the first oscillation transistor; a second oscillating circuit for outputting an oscillation signal having a second frequency, which includes a second oscillation transistor and a second switch circuit for turning on and off the second oscillation transistor; and a coupling circuit disposed between the output end of the first oscillating circuit and the output end of the second oscillating circuit, and the input end of a common circuit.
    Type: Grant
    Filed: June 23, 2000
    Date of Patent: September 11, 2001
    Assignee: Alps Electric Co., Ltd.
    Inventor: Hiroki Kobayashi
  • Publication number: 20010006357
    Abstract: An amplification circuit includes an inverter whose input node is connected to an output node of an oscillation circuit and a resistance element connected in parallel with the inverter. A filter circuit is connected to an input node of the amplification circuit, and both a level-shift circuit and a Schmitt circuit are connected to a stage subsequent to the filter circuit. The filter circuit, level-shift circuit and Schmitt circuit eliminate noise from an oscillation signal. The Schmitt circuit wave-shapes the oscillation signal and outputs the wave-shaped signal as a clock.
    Type: Application
    Filed: December 26, 2000
    Publication date: July 5, 2001
    Inventor: Hiroaki Yamamoto
  • Patent number: 6252470
    Abstract: An oscillating circuit adjusts its oscillating frequency through the following method. A tip-open type strip-line stub coupled to the base terminal of the transistor. An electrical length of the stub is changed by an adjusting mechanism such as coupling the stub with conductive small lands provided near the stub tip by a chip resistor. A “kotatsu” employs a remote controller including this oscillating circuit.
    Type: Grant
    Filed: November 30, 1999
    Date of Patent: June 26, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Kazuaki Togawa
  • Patent number: 6181216
    Abstract: An oscillator is formed using a Field-Effect Transistor (FET) in a Colpitts configuration. The circuit has a resistor from source to ground. Also connected to the source are two capacitors, one between the source and ground while the other is from source to gate. These capacitors provide a phase-shifted feedback signal to the gate. Also connected to the gate is the varactor tank, which has a voltage variable reactance that is used to tune the oscillation to the desired frequency. Between the drain of the FET and the supply voltage is a resistor-capacitor network. Between two series resistors a shunt capacitor is added to minimize local oscillator leakage onto the Vdd line. The resistor network also provides impedance for the Pre-Scalar output, which is simply a connection to the drain of the FET. The pre-scalar output is used to provide a reference signal to the phase-locked loop, which generates the correction voltage to the oscillator's VCO input.
    Type: Grant
    Filed: July 19, 1999
    Date of Patent: January 30, 2001
    Assignee: General Instrument Corporation
    Inventor: Matthew Glenn Waight
  • Patent number: 6163223
    Abstract: A dual-mode multiple signal source/local oscillator module is capable of operating in either an independent offset mode or a common offset mode. The module includes first and second coarse frequency sources, a first signal generator coupled to the first coarse frequency source, a second signal generator, and an offset switch coupled to the second signal generator. The offset switch connects the second signal generator to either the first coarse frequency source in the common offset mode, or the second coarse frequency source in the independent offset mode. Operation of the sources in the common offset mode provides the benefits of dynamic tracking which include reduction of receiver IF phase noise and spurious signal content, improved receiver IF settling speed, and higher measurement accuracy.
    Type: Grant
    Filed: September 2, 1999
    Date of Patent: December 19, 2000
    Assignee: Anritsu Company
    Inventors: Peter Kapetanic, Oggi Park Lin
  • Patent number: 6057740
    Abstract: A method and a stable local oscillator system for providing a signal centered at a frequency of interest to a radio frequency (RF) converter. The method includes the following steps: (a) generating an output signal which comprises a fundamental signal centered at a fundamental frequency and a harmonic signal centered at the frequency of interest which is equal to an integral multiple of the fundamental frequency; (b) amplifying the output signal such that the harmonic signal is amplified more than the fundamental signal; and (c) bandpass filtering the amplified output signal such that the amplified fundamental signal is substantially suppressed and the amplified harmonic signal is used as a local oscillator in the RF converter. An example is given for the case where the fundamental frequency is 1.67 gigahertz (GHz), and the frequency of interest is 3.34 GHz which is the second harmonic.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: May 2, 2000
    Assignee: Northrop Grumman Corporation
    Inventors: Stephen James Consolazio, Dave Biscan, Albert Ferek
  • Patent number: 6018274
    Abstract: The present invention relates to a radio receiver, particularly to a receiver for use in single-frequency applications, such as GPS, and to a frequency generator, which may be used in such a radio receiver, or elsewhere. The frequency generator comprises a tuned circuit connected between the emitter of the transistor and ground, such that a voltage signal at the basic frequency appears on the emitter terminal of the transistor. This arrangement has the advantage that the two frequencies appear on separate ports, and provides a radio receiver including radio receiver circuitry for connection to digital signal processing circuitry, reducing the complexity of the overall circuit. Additionally, there is a radio receiver wherein separate first and second local oscillator signals are generated from the terminal of s single transistor, avoiding the need for cascade multiplication stages, again reducing the size and complexity of the overall circuit.
    Type: Grant
    Filed: June 21, 1996
    Date of Patent: January 25, 2000
    Assignees: STMicroelectronics Limited, University of Bristol
    Inventors: Philip G. Mattos, Mark A. Beach
  • Patent number: 5923225
    Abstract: Active electronic circuits are immersed in photonic bandgap crystals (PBC's) that form part of transmission lines for propagation of output signals of the electronic circuits. The output signals of the electronic circuits are accompanied by noise signals that result from spontaneous emission in emission frequency bands which are associated with the active electronic circuits. The PBC's are configured to have photonic bandgaps that include at least a portion of the emission frequency bands. Because the active electronic circuits are immersed in the photonic bandgap crystal, the launch of at least a portion of the noise signals into the transmission line is thereby inhibited. Consequently, the output signal and less than all of the noise signals are propagated along the transmission line, i.e., the noise content of the circuit output is reduced.
    Type: Grant
    Filed: October 3, 1997
    Date of Patent: July 13, 1999
    Inventor: Hector J. De Los Santos
  • Patent number: 5920234
    Abstract: A transmitter circuit includes an output impedance and a buffered oscillator. The buffered oscillator includes a resonator for generating a reference signal and an amplifier coupled with the resonator for amplifying the reference signal. A first resonant tank generates an oscillating output signal in response to the amplified reference signal. A buffer circuit buffers the oscillating output signal and lowers the output impedance.
    Type: Grant
    Filed: June 24, 1998
    Date of Patent: July 6, 1999
    Assignee: UT Automotive Dearborn, Inc.
    Inventor: John P. Hill
  • Patent number: 5770977
    Abstract: The ability to achieve ultra-fast frequency settling times with good frequency resolution and high absolute accuracy over significant bandwidth at microwave frequencies ranging over three octaves. The implementation is an open-loop system requiring little or no compensation of temperature. This is accomplished by providing a frequency doubled direct digital synthesizer output to up/down convert a microwave frequency source. A special tracking filter architecture coupled to the microwave source provides the suppression of unwanted products. Fixed frequency set-on and swept bandwidths in excess of 300 MHz have been demonstrated. This is accomplished by using a direct digitally synthesized quadrature phased carrier which can be set to any frequency within a 350 MHz bandwidth to coherently up/down convert a low phase-noise microwave frequency to the sum or the difference frequency product.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: June 23, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: Stephen J. Uurtamo
  • Patent number: 5721515
    Abstract: A high stability clock oscillator circuit that has no inductors in the oscillator circuit itself. In the preferred embodiment neither the collector, the base, nor the emitter of the transistor is grounded and the oscillator output is taken from the collector of the transistor. In an alternate embodiment the collector is AC grounded and the output is taken across a load resistor coupled between the emitter of the transistor and ground. The resulting oscillator is a high stability oscillator that can be used as a dock oscillator in high frequency circuits.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: February 24, 1998
    Assignee: RF Monolithics, Inc.
    Inventors: Alan R. Northan, Peter V. Wright
  • Patent number: 5712596
    Abstract: In an oscillator arrangement (VCXO), an oscillation loop (OSL) oscillates at, approximately, the fundamental frequency of a crystal (XTL) included therein. The output signal (Sosc) of the oscillator arrangement (VCXO) is a harmonic extracted from the oscillation loop (OSL). To vary the frequency of the output signal (Sosc), a tuning circuit (VAR) is included in the oscillation loop (OSL). A stage (FIL) in the oscillator arrangement (VCXO) prevents harmonic feedback into the oscillation loop (OSL). Such an oscillator arrangement (VCXO) can be tuned over a relatively large frequency range and has a monotonous tuning characteristic.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: January 27, 1998
    Assignee: U.S. Philips Corporation
    Inventor: Alfonsus M. Van Amesfoort
  • Patent number: 5699021
    Abstract: A balanced and buffered oscillator and transmitter arrangement includes a first and second oscillator, each of which include a resonator for generating a reference signal, an amplifier for amplifying the reference signal, a resonant tank for generating an oscillating output signal in response to the amplified reference signal, and a buffer circuit for buffering the respective oscillating output signal such that the effects of a parasitic impedance are minimized.
    Type: Grant
    Filed: April 16, 1996
    Date of Patent: December 16, 1997
    Assignee: United Technologies Automotive, Inc.
    Inventor: John P. Hill
  • Patent number: 5697095
    Abstract: There is provided a tuner capable of improving reliability thereof with reduced power consumption and reduced heat generation. In the tuner, one wideband amplifier circuit including one transistor constitutes a buffer amplifier. The wideband amplifier circuit is coupled with a first local oscillator circuit in a DC coupling style. With the above-mentioned arrangement, the buffer amplifier is allowed to have a simplified circuit construction and reduce noises. Since the amplifier circuit and the local oscillator circuit are coupled with each other in a DC coupling style, reduced power consumption can be achieved.
    Type: Grant
    Filed: May 22, 1995
    Date of Patent: December 9, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Syuuji Matsuura
  • Patent number: 5625324
    Abstract: The frequencies of N oscillators are summed to provide a signal generator output signal. Because the phase noise power spectral densities of the oscillators add as power, the frequency summed output exhibits a noise degradation over a single oscillator of only 10 log(N). The signal generator is implemented to assure independence of the oscillator noise contributions, with phase locking the oscillators to a common frequency for ease of spurious signal control.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 29, 1997
    Assignee: Hughes Electronics
    Inventors: Steve I. Hsu, Stephen D. Taylor