Adjustable Frequency Patents (Class 331/48)
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Patent number: 6437621Abstract: A waveform shaping circuit is provided so that the duty factor of clock pulses can be set to 50% with high accuracy even if the clock pulses are of a low voltage and a high frequency. An inverter which receives the clock pulses through an alternating current coupling capacitor is provided with a non-linear limiter element for limiting an amplitude of an output symmetrically on positive and negative sides thereof. A first current-limiting impedance and a second current-limiting impedance are connected between a power supply side terminal of the inverter and a power supply bus and between a grounding side terminal of the inverter and a grounding bus, respectively.Type: GrantFiled: March 26, 2001Date of Patent: August 20, 2002Assignee: Hitachi, Ltd.Inventors: Kazuo Kato, Takashi Sase, Takashi Hotta, Fumio Murabayashi
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Patent number: 6417740Abstract: A variable frequency signal generator, in the form of a voltage controlled oscillator, provides wide-band and/or multi-band output frequency operation using two control voltage inputs. A pair of LC oscillator circuits are cross-coupled through a transconductance control circuit. The oscillator circuits provide quadrature output frequency signals. The oscillator circuits include MOSFET varactors controllable by a first control voltage which can be used to drive the varactors into inversion or depletion operating modes which correspond to respective output signal frequency bands. A second control voltage is provided to the transconductance control circuit to control currents injected from each oscillator to the other, thereby selecting a particular output frequency within the range of the frequency band determined by the first control voltage.Type: GrantFiled: February 22, 2001Date of Patent: July 9, 2002Assignee: Chartered Semiconductor Manufacturing Ltd.Inventors: Do Manh Anh, Zhao Ruiyan, Ma Jian-Guo, Yeo Kiat Seng, Chew Kok Wai
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Patent number: 6292063Abstract: 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: GrantFiled: August 8, 2000Date of Patent: September 18, 2001Assignee: Alps Electric Co., Ltd.Inventors: Takeshi Tanemura, Yasuhiro Ikarashi
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Patent number: 6236366Abstract: A semiconductor module having a built-in antenna element for use in a system of a band of millimeter-waves or quasi-millimeter-waves comprises a substrate, an antenna element, a semiconductor integrated circuit, and a hermetically sealing portion. The antenna element is mounted on one side of the substrate. The semiconductor integrated circuit is also formed on the same side of the substrate as of the antenna element. The semiconductor integrated circuit includes at least either of a transmitter signal processing circuit composed mainly of an amplifier circuit and a frequency converter circuit for processing a signal which is exploited in the system of the band of millimeter-waves or quasi-millimeter-waves and transmitted to the antenna element, and a receiver signal processing circuit composed mainly of an amplifier circuit and a frequency converter circuit for processing a signal which is received by the antenna element and exploited in the system of the band of millimeter-waves or quasi-millimeter-waves.Type: GrantFiled: August 27, 1997Date of Patent: May 22, 2001Assignee: Olympus Optical Co., Ltd.Inventors: Toshio Yamamoto, Yasutake Hirachi
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Patent number: 6188292Abstract: A first and a second fixed-frequency oscillator coupled in a ring topology to generate a variable frequency output is provided. Frequency variation is achieved by varying the coupling between the two oscillators. The coupling may be varied by using a variable current or voltage source. The first fixed frequency oscillator may generate a first signal which is ninety degrees out of phase with a second signal generated by the second fixed frequency oscillator. An apparatus is provided comprising a first oscillator which produces a first signal, a second oscillator which produces a second signal which is about ninety degrees out of phase with the first signal, and first and second coupling modules, coupling the first and second oscillators. A frequency control circuit is provided which varies the coupling of the first and second coupling modules and thereby varies the frequency of the first signal and the second signal.Type: GrantFiled: September 21, 1999Date of Patent: February 13, 2001Assignee: Lucent Technologies Inc.Inventor: Ting-Ping Liu
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Patent number: 6150892Abstract: A method and device for frequency synthesizing, in which the digital frequency synthesizer includes a clock pair having two similar ring-oscillators to separately generate a search frequency and an output frequency, a frequency tracking unit, and a clock controlling unit. The frequency-search method includes two stages: one stage is the coarse search stage based on the "Prune-and-Search", and other stage is the fine search stage based on the "fixed-step" algorithm. In order to determine which search scheme is used to search the target frequency and to determine the lock status, two cost functions for search and lock-in are derived. These two cost functions define the search threshold and the lock threshold, and these thresholds define the cost window and the lock window. If the frequency error is higher than both the search and lock thresholds, a coarse search is activated to estimate the correct frequency.Type: GrantFiled: October 30, 1998Date of Patent: November 21, 2000Assignee: TFL Lan Inc.Inventors: Chen-Yi Lee, Terng-Yin Hsu, Bai-Jue Shieh, Chung Cheng Wang
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Patent number: 6114916Abstract: An oscillation apparatus is provided with a signal input unit for supplying a pulse sequence consisting of pulses sequentially continuously occurred; a state quantity generating unit for generating state quantity having a value which is monotonously increased with the passage of time; a state quantity transition unit for transferring a value of state quantity in the course of generation in said state quantity generating unit to a value changed by a predetermined amount in a varying direction of the value of the state quantity with respect to a present value of the state quantity, whenever one pulse is fed from said signal input unit to said state quantity transition unit; a state quantity reset unit for comparing the present value of the state quantity generated in said state quantity generating unit with a predetermined threshold value, and resetting the present value of the state quantity generated in said state quantity generating unit to a predetermined initial value when the present value reaches the thrType: GrantFiled: September 4, 1997Date of Patent: September 5, 2000Assignee: Fujitsu LimitedInventors: Miyuki Koyanagi, Koichi Murakami
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Patent number: 6037842Abstract: An integrated circuit complementary metal-oxide silicon (CMOS) voltage controlled oscillator (VCO) includes a plurality of variable delay elements, connected in a ring configuration, each variable delay element including a pair of parallel connected differential CMOS sections. The parallel-connected differential CMOS sections of each variable delay element are controlled by a differential control voltage whose magnitude sets relative levels of operation of the two differential sections of each variable delay element. These relative levels of operation determine the delay through the variable delay element. A current mirror circuit provides the differential control voltage.Type: GrantFiled: April 21, 1998Date of Patent: March 14, 2000Assignee: Applied Micro Circuits CorporationInventors: Thomas Clark Bryan, Allen Carl Merrill
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Patent number: 6031426Abstract: A phase-locked-loop-stabilized voltage controlled oscillator relies on a sampling of the analog-frequency-control voltage of a voltage-controlled oscillator in a phase-locked-loop circuit to act as a reference voltage for a second free-running voltage-controlled oscillator. A vernier-adjustment voltage is injected into the control input of the second voltage-controlled oscillator to produce a finely variable derivative frequency not otherwise producible by a conventional phase-locked-loop circuit.Type: GrantFiled: May 29, 1998Date of Patent: February 29, 2000Assignee: Avant! CorporationInventor: Sitaramarao S. Yechuri
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Patent number: 6020781Abstract: A step-up circuit includes a selection control circuit 50 for activating a start/stop signal STP by detecting an external power-supply voltage Vcc, which is stable at 3.3 V, to reach 2.0 V or more, a ring oscillator circuit 30 for generating and outputting a clock of a high frequency Fs when the start/stop signal STP is inactive, a ring oscillator circuit 10 for generating a clock of a low frequency fo, a selection circuit 40 for selecting the output of the oscillator 30 when the start/stop signal STP is inactive and for selecting the output of the oscillator 10 when the start/stop signal is active, and a charging pump circuit 20 driven by the clocks. High frequency Fs is initially used to quickly bring an output voltage up to a desired operating level and low frequency fo is used, in order to conserve power, to maintain the operating level once a predetermined level of the external power supply voltage Vcc has been reached in order to conserve power.Type: GrantFiled: September 17, 1997Date of Patent: February 1, 2000Assignee: Fujitsu LimitedInventor: Shinya Fujioka
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Patent number: 6016081Abstract: A tunable oscillator includes an input for receiving an input signal from a source of precision frequency such as a CMOS quartz crystal oscillator. The tunable oscillator converts the frequency of the input signal to a first current using a frequency to current converter. The current produced is proportional to a first capacitor, C1. The first current is replicated to produce a subsequent current using a current mirror structure. The subsequent current is then used to generate a periodic signal using a current to frequency converter. The output frequency of the current to frequency converter is inversely proportional to a second capacitor, C2. As such the output frequency of the tunable oscillator is tunable by changing the value of the capacitance ratio C1/C2. The invention is suitable for applications that require a precision tunable source of frequency such as automated test equipment (ATE) and electrical instrumentation.Type: GrantFiled: July 17, 1998Date of Patent: January 18, 2000Inventor: Timothy G. O'Shaughnessy
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Patent number: 5982240Abstract: A voltage controlled oscillator comprises first oscillating stage for outputting a first frequency signal, second oscillating stage for outputting a second frequency signal different from the first frequency signal, a buffer stage connected with said first and second oscillating stages, the buffer stage receiving said first and second frequency signals to generate an output signal.Type: GrantFiled: November 26, 1997Date of Patent: November 9, 1999Assignee: TDK CorporationInventor: Katuhiko Hayashi
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Patent number: 5974362Abstract: A signal generator comprises a number of independent signal sources each of which can be controlled to generate predetermined frequencies and modulation. The outputs of these signal sources can be made available separately at output ports or can be combined within the signal generator to provide a combined output signal. The output signals are sensed at the output ports, and are calibrated against a stored correction tabulation to ensure that they have the correct signal level at the output ports. Such a signal generator is useful for the measurement and testing of complex electrical and electronic products.Type: GrantFiled: November 14, 1996Date of Patent: October 26, 1999Assignee: Marconi Instruments LimitedInventor: David P Owen
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Patent number: 5926641Abstract: A circuit for controlling clock frequency change circuitry to control a frequency of a system clock in response to a clock frequency indication, wherein operating circuitry of an electronic system operates responsive to the system clock. First flip-flop circuitry has an input portion coupled to receive the clock frequency indication. The first flip flop circuitry is configured to pass data from the input portion to an output portion responsive to a first polarity transition of the internal clock. Second flip-flop circuitry has an input portion coupled to the output portion of the first flip-flop circuitry. The second flip-flop circuitry configured to pass data from an input to an output portion responsive to a second polarity transition of the internal clock.Type: GrantFiled: July 10, 1998Date of Patent: July 20, 1999Assignee: National Semiconductor CorporationInventor: Michael John Shay
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Patent number: 5912596Abstract: A method and system in an integrated circuit for frequency tuning oscillator circuits. An oscillator circuit within an integrated circuit is formed on a substrate such that the oscillator circuit is coupled to an inductor component. The inductor component includes a first inductor positioned parallel to a second inductor such that a total effective inductance is associated with the first and second inductors. The first inductor is formed from a first spiral coil layer which is coupled to a second spiral coil layer on the substrate. The second inductor is formed of a single spiral coil layer on the substrate, wherein the single spiral coil layer provides an inductive feedback signal to the oscillator circuit when electrical current flows through the single spiral coil layer in response to current flowing through the first spiral coil layer and the second spiral coil layer.Type: GrantFiled: January 26, 1998Date of Patent: June 15, 1999Assignee: International Business Machines CorporationInventor: Uttam Shymalindu Ghoshal
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Patent number: 5864258Abstract: A voltage-controlled oscillator, with high noise rejection of the supply voltage, includes a plurality of delay cells in an odd number N.gtoreq.3, which are connected to form a first ring oscillator and powered by the difference between a supply voltage Vcc and a variable regulating voltage VR. The VCO comprises at least one second ring oscillator formed by a plurality of delay cells in an odd number M.gtoreq.3, at least one of which is also a delay cell of the first oscillator and at least two of which do not belong to the first oscillator. At least one of these two cells is powered by a constant voltage (Vcc), in such a manner that the two oscillators operate at the same frequency and the interaction between the two oscillators introduces a high-frequency negative feedback which has the effect of effectively reducing the noise of the supply voltage Vcc.Type: GrantFiled: May 1, 1997Date of Patent: January 26, 1999Assignee: SGS-Thomson Microelectronics S.r.l.Inventors: Paolo Cusinato, Melchiorre Bruccoleri
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Patent number: 5852384Abstract: A dual band oscillator circuit according to the present invention comprises an oscillator circuit portion that oscillates at a first frequency, an oscillator circuit portion that oscillates at a second frequency, a buffer amplifier circuit portion to which an output of the first oscillator circuit portion is input through a first stage-to-stage coupling element and an output of the second oscillator circuit portion is input through a second stage-to-stage coupling element. Operation is switched between the first and second oscillator circuits by an externally applied control voltage signal.Type: GrantFiled: April 18, 1997Date of Patent: December 22, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Makoto Sakakura, Hisanaga Miyoshi, Kouji Hashimoto, Nobuo Fuse, Hiroaki Kosugi, Kaoru Ishida
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Patent number: 5821820Abstract: A voltage controlled oscillator operable on two widely separated frequency bands, such as 900 MHz and 1.8 GHz for example. The voltage controlled oscillator includes two negative resistance generators (32, 34) which share a common tunable tank circuit (26) and a common impedance matched combiner circuit (28) which provides the RF output (36). The VCO uses only one varactor (30) to tune both frequency bands. Separate negative resistance generators (32, 34) are used to provide optimum frequency selectivity within each frequency band.Type: GrantFiled: August 15, 1997Date of Patent: October 13, 1998Assignee: Motorola Inc.Inventors: James R. Snider, Glen O. Reeser
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Patent number: 5702426Abstract: Apparatus and methods for adjusting an electrical parameter of an electronic device, notably of an active implantable medical device such as a pacemaker or cardiac defibrillator, and an implementing monolithic integrated circuit for conducting the adjustment.Type: GrantFiled: November 16, 1995Date of Patent: December 30, 1997Assignee: ELA Medical S.A.Inventors: Pascal Pons, Renzo Dal Molin
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Patent number: 5668507Abstract: A method and apparatus for generating noise to be used in evaluation and testing of digital or analog integrated circuits. One or more noise generators fabricated on a substrate generate noise representative of the digital switching noise generated by a digital integrated circuit. The noise generator may be programmable to generate noise over a wide frequency and amplitude range. In addition, a plurality of noise generators may be used to independently and simultaneously generate noise signals with multiple frequencies and amplitudes. A test circuit, either analog or digital, is fabricated on the same substrate. The generated noise signal(s) are generated for use in the evaluation and testing of the effects of the noise on the analog or digital test circuit.Type: GrantFiled: July 22, 1996Date of Patent: September 16, 1997Assignee: International Business Machines CorporationInventors: David William Boerstler, Daniel Mark Dreps
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Patent number: 5450039Abstract: An integrated circuit has a self-contained voltage control oscillation circuit wherein the oscillating frequency is controlled according to a control voltage; The circuit includes a first oscillation circuit which forms a first oscillation loop including a first amplifier for generating a first output signal with an oscillating frequency which is controlled according to an operating current of the first amplifier and a second oscillation circuit which forms a second oscillation loop including a second amplifer for generating a second output signal with an oscillating frequency which is controlled according to an operating current of the second amplifer; A circuit for generating a control voltage controls the operating currents of the first and second amplifers and a current regulating circuit for generating an operating current regulating signal regulates the operating currents of the first and second amplifers.Type: GrantFiled: September 23, 1993Date of Patent: September 12, 1995Assignee: Rohm Co., Ltd.Inventors: Isoshi Takeda, Shigeyoshi Hayashi
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Patent number: 5418496Abstract: A serial data clock receiver circuit (11) is provided that synchronizes a clock signal to data. The serial data clock receiver circuit (11) comprises a control circuit (21), a dual oscillator circuit (19), and a phase locked loop circuit (22). The control circuit (21) arms the dual oscillator circuit (19) for being enabled during an idle period. The phase locked loop circuit (22) provides a reference voltage for the dual oscillator circuit (19). The dual oscillator circuit (19) is responsive to both the data and control circuit (19) for providing a clock signal.Type: GrantFiled: February 7, 1994Date of Patent: May 23, 1995Assignee: Motorola, Inc.Inventors: David Ford, Emil N. Hahn, Michael D. Reed, Nandini Srinivasan, Philip A. Jeffrey
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Patent number: 5418497Abstract: BiCMOS technology is used in the design of a VCO (200) to improve low DC operation. The VCO (200) includes two coupled oscillator circuits (201,219) tuned to different fixed frequencies such that the oscillator resonant frequencies define the tuning range of the VCO (200). The oscillator circuits (201, 219) are coupled such that the frequency of oscillation of the VCO (200) is adjustable via variable resistors (206, 214) by manipulating the bias currents to the two oscillator circuits (201,219). A biasing circuit (208) along with variable resistors (206 and 214) provide the DC bias to the oscillator circuits (201 and 219). The biasing circuit (208) maintains the sum of the biasing currents to the oscillator circuits constant. The oscillator circuits (201, and 219) are interconnected utilizing an RF coupling circuit (211). The VCO (200) is capable of operating at voltages as low as 1.8 volts DC.Type: GrantFiled: July 5, 1994Date of Patent: May 23, 1995Assignee: Motorola, Inc.Inventor: Frederick L. Martin
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Frequency synthesizer using three subfrequency synthesizers for generating two different frequencies
Patent number: 5408201Abstract: A frequency synthesizer includes three subfrequency synthesizers: a first synthesizer generating a first subfrequency varying in units of a frequency step, a second synthesizer generating a second subfrequency varying in units of a frequency step being N times the first frequency step, and a third synthesizer generating a third subfrequency varying in units of the first frequency step. One output signal is obtained by mixing the first subfrequency and the second subfrequency. A second output signal is obtained by mixing the second subfrequency and the third subfrequency.Type: GrantFiled: May 20, 1994Date of Patent: April 18, 1995Assignee: NEC CorporationInventor: Susumu Uriya -
Patent number: 5398007Abstract: A baud rate generator has a first oscillator that generates a first clock signal, and a second oscillator that generates a second clock signal with higher frequency but lower frequency accuracy. The first oscillator employs an external resonator but the second does not. The baud rate generator uses the first clock signal to measure the frequency of the second clock signal, then determines a division ratio by which to divide the frequency of the second clock signal, then divides the second clock signal by this division ratio to generate a crock signal for use in serial communication.Type: GrantFiled: July 20, 1994Date of Patent: March 14, 1995Assignee: Oki Electric Industry Co., Ltd.Inventors: Seiichi Yamazaki, Sumihiro Takashima
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Patent number: 5339055Abstract: A frequency phase modulator which generates a phase modulator controlled slope voltage waveform. The controlled slope voltage waveform is controlled by coupling a first fixed frequency oscillator with a second variable frequency voltage controlled oscillator. The period of the ramp waveform (slope) is equal to the difference between the two frequencies. The phases of the two oscillators are compared and integrated to produce the phase modulator ramp waveform.Type: GrantFiled: December 18, 1992Date of Patent: August 16, 1994Assignee: Honeywell Inc.Inventor: Michael A. Wyatt
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Patent number: 5327582Abstract: A wideband transceiver using contiguous overlapping frequency range local oscillators (32, 34) for a high side or a low side local oscillator and an intermediate frequency approaching, within commercialy practical limits, but not exceeding one half of the total limited oscillator frequency range (71).Type: GrantFiled: January 24, 1992Date of Patent: July 5, 1994Assignee: Motorola, Inc.Inventor: Donald H. Wong
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Patent number: 5302920Abstract: An electrically controlled oscillator circuit having multi-phase outputs with programmable frequency. The circuit includes a ring oscillator having a plurality of inverting stages. Each stage has an output which is connected to a switch that can be programmed to select one of a plurality of capacitors with different values to change the frequency range of the oscillator. Controlled current is fed to the stages to vary the frequency of the oscillator within a selected frequency range. Using capacitors to change the frequency range of the oscillator reduces variations of the oscillator output frequency.Type: GrantFiled: October 13, 1992Date of Patent: April 12, 1994Assignee: NCR CorporationInventor: Ricky F. Bitting
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Patent number: 5179359Abstract: A digitally controlled oscillator (100) having a first oscillator circuit (108) for providing an oscillator signal F.sub.o of a defined frequency and a digital divider (110) for dividing the oscillator signal F.sub.o by a selectable number controlled by a digital word for providing a clock signal F.sub.clk. A second oscillator circuit (104) receives the clock signal F.sub.clk and provides a low frequency signal F.sub.c. The second oscillator circuit includes a digitally controlled resonator element (112) for determining the frequency of the low frequency signal and has a center frequency dependent upon the clock signal. Circuitry (118, 120, 138) is included for providing first and second pairs of quadrature phase shifted signals derived from the clock signal F.sub.clk and the low frequency signal F.sub.c and from the oscillator signal F.sub.o, respectively.Type: GrantFiled: March 16, 1992Date of Patent: January 12, 1993Assignee: Hughes Aircraft CompanyInventor: Scott C. McLeod
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Patent number: 4845692Abstract: A clocking device of substantially constant stability for short-term and long-term measurements. This clocking device comprises first generators of a clocking signal with substantially constant stability for short-term measurements, and second generators of a clocking signal of constant stability for long-term measurements. Means for the automatic locking of one of the said first or second clocking signals to the other clocking signal are provided, and enable the automatic frequency and/or phase locking of said signals. The automatic locking means have a time constant corresponding to the transition zone between the short-term and long-term measurements. The device can be applied in the high-precision time-measuring instruments industry and to air and space navigation instruments.Type: GrantFiled: April 18, 1988Date of Patent: July 4, 1989Assignee: Centre National D'Etudes SpatialesInventors: Jacques Groslambert, Michel Brunet
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Patent number: 4814727Abstract: A wide deviation tracking filter is provided which has the input signal to be tracked applied to a low frequency phase-locked loop circuit which performs coarse filtering of the phase noise on the input signal. A digital phase shifter is connected in series in the low frequency phase-locked loop and produces a pair of quadrature clock signals which are at the frequency of the input signal and at half the frequency of the output of the voltage control oscillator of the low frequency phase-locked loop. The pair of quadrature signals are connected to an image reject circuit. The image reject circuit is connected in series in the loop of a high frequency phase-locked loop which operates at a much higher frequency than the low frequency phase-locked loop and performs the function of further filtering the phase noise on the input signal to provide an output signal having ultra-low phase noise.Type: GrantFiled: December 18, 1987Date of Patent: March 21, 1989Assignee: Unisys CorporationInventor: Vaughn L. Mower
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Patent number: 4797636Abstract: A radio receiver includes a noise blanking system comprising a switching circuit in the signal path which is responsive to a blanking signal for preventing passage of signals. A blanking signal producing circuit is in the signal path ahead of the switching circuit and is responsive to predetermined noise signals received by the radio receiver for producing the blanking signal. The receiver also includes an AGC circuit for producing a gain control signal and a signal strength meter coupled for response to the gain control signal. A linearity control system comprises a current controlling circuit responsive to a meter control signal for controlling the current flow through the meter so as to increase the range of linear response of the meter. A signalling circuit is coupled with the AGC circuit and with the current controlling circuit and is responsive to the gain control signal for producing the meter control signal.Type: GrantFiled: June 20, 1986Date of Patent: January 10, 1989Assignee: General Research of Electronics, Inc.Inventors: Kazuyoshi Imazeki, Nobuaki Yokoyama
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Patent number: 4760351Abstract: A system is described which comprises many quartz resonators, all formed on the same quartz substrate. The method of fabrication ensures that all the resonators are mechanically and electrically isolated from each other. The oscillation frequencies of the resonators may be individually adjusted to different desired values during fabrication. Since the deviation from the optimum angle of cut is the same for all the resonators because they are all on the same substrate, all the resonators have the same temperature coefficient (change of frequency per degree change in temperature). Mounting the electronic circuitry on the quartz substrate simplifies the interconnections between the resonators and the circuitry, and reduces the size of the resulting device.Type: GrantFiled: August 22, 1986Date of Patent: July 26, 1988Assignee: Northern Illinois UniversityInventors: Darrell E. Newell, Alan P. Genis, Gregg Westberg, Susan M. Nemes
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Patent number: 4575688Abstract: The output signal frequencies of two current controlled oscillators are made to track closely by matching timing currents with a current mirror. A frequency difference between the output signals is obtained by establishing an additional timing current for only one of said oscillators.Type: GrantFiled: April 24, 1985Date of Patent: March 11, 1986Inventor: Alan D. Whitefoot
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Patent number: 4568889Abstract: In a distributed IMPATT structure, power is coupled out through a side contact. That is, in previously proposed distributed IMPATT structures, the gain medium (the active region of the IMPATT) operates as a transmission line. The prior art has attempted to couple output power from the gain medium through an end contact, i.e., through a contact which is perpendicular to the primary direction of energy propagation (and also to the direction of maximum elongation) of the active medium. In the present invention, a sidewall contact extends in a direction which is parallel to the principal direction of propagation of the energy in the active medium. Thus, the sidewall contact plus the active region together can be considered as a single transmission line. This extended transmission line is also connected to a second distributed semiconductor element which functions as a varactor.Type: GrantFiled: August 31, 1983Date of Patent: February 4, 1986Assignee: Texas Instruments IncorporatedInventor: Burhan Bayraktaroglu
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Patent number: 4540945Abstract: A highly stable, tunable oscillator circuit includes a crystal oscillator providing a reference pulse signal of frequency fcry, a voltage-to-frequency converter responsive to a control voltage vc for providing a control pulse signal of frequency fv substantially lower than fcry, and a flip-flop circuit receiving the reference and control signals and providing a negative going pulse signal synchronized with the reference signal and having a frequency fv and a pulse width equal to l/fcry. The signal provided by the flip-flop circuit and the complement of the reference signal are received by a NAND gate which periodically removes a pulse from the reference signal at intervals of l/fv and provides a resulting signal having a frequency of (fcry).sup.2 /(fcry+fv). The resulting signal is received by a frequency divider network which divides the frequency of resulting signal by an integer N and provides an output signal of a desired frequency.Type: GrantFiled: September 1, 1982Date of Patent: September 10, 1985Assignee: Fuji Electric Co., Ltd.Inventor: Kazuo Kuroki
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Patent number: 4514696Abstract: A radio frequency numerically controlled oscillator comprising N one bit adders each providing sum and carry outputs to one of N two bit registers. Sum, carry and frequency selection inputs are combined by each adder to form sum and carry outputs. These results are held by the associated register when triggered by a clock input. A fast parallel adder/latch is employed which has two stages connected serially to generate sums on opposite phases of a two phase clock.Type: GrantFiled: December 27, 1982Date of Patent: April 30, 1985Assignee: Motorola, Inc.Inventor: Thad J. Genrich
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Patent number: 4409565Abstract: The invention relates to a circuit arrangement for producing a low frequency alternating current, such as is particularly used for electric massaging. Any desired frequency characteristics and beats may be produced by the interconnecting of several generators having different, adjustable fundamental frequencies, and by an adjustability of the coupling components. These frequency characteristics and beats have proven to be particularly effective. Above all, the components of the line frequencies of 50-60 Hz, which are dangerous to the human body, are avoided.Type: GrantFiled: February 17, 1981Date of Patent: October 11, 1983Inventor: Erich Scherer
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Patent number: 4325036Abstract: Temperature compensating circuit for an electronic timepiece having two piezo electric resonators having different frequency-temperature characteristics.Two piezo electric resonators are a major resonator having smaller frequency variation rate in temperature variation and a subsidiary resonator having larger frequency variation rate in temperature variation.And also the temperature compensating circuit includes a variable counter for counting the output signal of the major oscillator having the major resonator, a gate time setting circuit controlled by both the outputs of subsidiary and the variable counter, and a counter for counting the output signal of the major oscillator.As a result, the temperature compensating circuit is able to improve the accuracy of the timepiece.Type: GrantFiled: May 23, 1980Date of Patent: April 13, 1982Assignee: Kabushiki Kaisha Daini SeikoshaInventor: Tsuneo Kuwabara
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Patent number: 4241308Abstract: The frequency and phase of an output signal from an oscillator circuit are controlled with accuracy by a digital input word. Positive and negative alterations in output frequency are both provided for by translating all values of input words so that they are positive. The oscillator reference frequency is corrected only in one direction, by adding phase to the output frequency of the oscillator.The input control word is translated to a single algebraic sign and the digital 1 is added thereto. The translated input control word is then accumulated. A reference clock signal having a frequency at an integer multiple of the desired frequency of the output signal is generated. The accumulated control word is then compared with a threshold level. The output signal is adjusted in a single direction by dividing the frequency of the reference clock signal by a first integer or by an integer different from the first integer.Type: GrantFiled: December 29, 1978Date of Patent: December 23, 1980Inventors: Alan M. Administrator of the National Aeronautics and Space Administration, with respect to an invention of Lovelace, Alfred Cellier, Douglas C. Huey, Lit N. Ma
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Patent number: 4121174Abstract: A power combining device for combining the microwave power from a plurality of solid state devices comprises a housing defining a resonator cavity with a plurality of co-axial microwave circuits, including a microwave diode at one end of each circuit and a tapered adjustable attenuator at the other end thereof, which are positioned annularly about the resonator cavity so that the energy generated therein is combined within the cavity and transmitted by way of a common outlet. The power combiner is provided with a broad range of bandwidth adjustment by providing for the adjustment of many of the parameters of the system including the length of the circuits, the damping of the circuits, and length of the resonator cavity, and the degree of coupling to adjacent circuits.Type: GrantFiled: October 31, 1977Date of Patent: October 17, 1978Assignee: General Dynamics CorporationInventor: Richard Aston
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Patent number: 4103252Abstract: A human touch on an etched copper electrode produces a capacitive change to vary the time constant of an RC network as a part of an oscillator. The variation in the capacitance of the sensor changes the time constant of the RC network which results in a change in frequency of the output signal of the oscillator. This change in frequency thus varies with the human touch to the copper electrode. To develop a directional indication of the touch position, four electrodes are arranged in opposed pairs along orthogonal axes. Each electrode is part of an RC network connected to an oscillator with each of the four oscillators identified with one of the four positions along the orthogonal axes. The output signal from each of the oscillators is transmitted to timing and control circuitry that generates four separate pulse trains, one pulse train identified with each of four positions along the orthogonal axis.Type: GrantFiled: November 26, 1976Date of Patent: July 25, 1978Assignee: Xerox CorporationInventor: Thomas W. Bobick
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Patent number: 4001716Abstract: A digital oscillator with output frequency accurately changeable from one period to the next. A plurality of retriggerable monostable multivibrators having discretely different design pulse widths are OR'd to an output monostable multivibrator having the narrowest design pulse width. The plurality of monostable multivibrators are triggered in common by the OR'd outputs thereof such that the longest pulse width one thereof defines the period of the output monostable multivibrator. Logic enabling means permit selection of multivibrator outputs to be OR'd.Type: GrantFiled: February 17, 1976Date of Patent: January 4, 1977Assignee: Rockwell International CorporationInventors: Ronald L. Swanson, Lyle R. Strathman
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Patent number: 3999049Abstract: Synthesizer of multifrequency signals for telephone sets, each multifrequency signal being formed by two concomitant sinusoidal signals of different basic frequencies, said frequencies forming pairs respectively corresponding to the decimal digits and being sub-multiples of a common clock frequency. The sinusoidal signals are pulse trains whose repetition rate varies steppedly in function of time in the following manner. The period of a sine function is divided into p parts and the amplitude of the function taken from the tangent to the negative peaks of the sine curve for p equidistributed values of the argument 2.pi.i/p, i varying from l to p, are approximated by p amplitude values. The periods of the signals having the basic frequences are divided into p time intervals and during these time intervals, a pulse train generator is operated in such a way that its pulse repetition rate be proportional to said amplitude values.Type: GrantFiled: September 29, 1975Date of Patent: December 21, 1976Inventors: Bernard G. Roche, Jean E. Milon
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Patent number: 3971896Abstract: A two tone generator using switching transistors in two LC resonance circuits each composed of a coil and a capacitor for producing a multifrequency signal in the form of two-tone signal by switching the value of the inductances of the coils in response to the control of push-button switches, in which only one make contact is actuated in response to the depression of each push button, so that the ON-OFF output of the contact is employed to control selected ones of switching transistors in each of the two resonance circuits for determining the oscillation frequencies of a two-tone oscillator associated with the two LC resonance circuits. The switching transistors comprises a first group of either NPN transistors or PNP transistors and a second group of NPN transistors or PNP transistors. The switching transistors are coupled with the two LC resonance circuits to switch the value of the inductance of each coil in response to the turning ON of the collector-emitter path thereof.Type: GrantFiled: November 13, 1974Date of Patent: July 27, 1976Assignee: Iwasaki Tsushinki Kabushiki KaishaInventor: Kouichi Sekiguchi
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Patent number: 3953852Abstract: A modified Huggin's Scanner whose tunable signal bandwidth can be broadened ithout affecting the beam position and whose output beam direction is dependent on the control of a resistor. Two separate voltage controlled oscillators are utilized in this system in addition to modifying the input frequency controls to the scanner.Type: GrantFiled: July 13, 1973Date of Patent: April 27, 1976Assignee: The United States of America as represented by the Secretary of the NavyInventors: Wallace E. Anderson, Albert D. Krall, Albert M. Syeles, Oscar J. Van Sant