Fine Tuning Patents (Class 455/192.3)
  • Patent number: 9162875
    Abstract: An inertial sensor is described in which a resonant element is driven by control electronics into resonance. The control electronics includes an oscillator. A circuit is provided for matching the frequency of the oscillator with the frequency of the output of the resonant element such that the time to operation from start up of the sensor is minimized and the requirement of frequency matching a given sensor to the control electronics is removed.
    Type: Grant
    Filed: April 5, 2011
    Date of Patent: October 20, 2015
    Assignee: SILICON SENSING SYSTEMS LIMITED
    Inventors: Michael Durston, David Beasley, Kevin Townsend
  • Patent number: 8965316
    Abstract: A circuit tuneable between first and second frequencies comprising gain control circuitry operable to control the gain of the circuit between the first and second frequencies, the gain control circuitry comprising a resistor network having: at least two resistor lines arranged in parallel, each resistor line comprising one or more resistors; and for each resistor line, a switch operable to select or deselect the corresponding resistor line; the resistor lines and switches being arranged such that the net resistance of the resistor network is the parallel sum of each of the selected resistor lines; and logic circuitry configured to control said switches so as to minimize the variation in gain of the circuit between the first and second frequencies.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: February 24, 2015
    Assignee: Cambridge Silicon Radio Limited
    Inventor: Sever Cercelaru
  • Patent number: 8712360
    Abstract: A system includes a first clock module, a global positioning system (GPS) module, a phase-locked loop (PLL) module, a cellular transceiver, and a baseband module. The first clock module generates a first clock reference. The GPS module operates in response to the first clock reference. The WLAN module operates in response to the first clock reference. The PLL module generates a second clock reference by performing automatic frequency correction (AFC) on the first clock reference in response to an AFC signal. The cellular transceiver receives radio frequency signals from a wireless medium and generates baseband signals in response to the received radio frequency signals. The baseband module receives the baseband signals, operates in response to a selected one of the first clock reference and the second clock reference, and generates the AFC signal in response to the baseband signals.
    Type: Grant
    Filed: September 9, 2013
    Date of Patent: April 29, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Gregory Uehara, Alexander Zaslavsky, Brian T. Brunn
  • Patent number: 8634501
    Abstract: A method and apparatus is disclosed to process a received single stream communication signal and/or a multiple stream communication. A communications receiver is configured to receive the received communication signal. A communications receiver determines whether the received communication signal includes a single stream communication signal or a multiple stream communication signal. The communications receiver determines whether a received communication signal complies with a known single stream communications standard. The communications receiver determines whether the received communication signal complies with a known multiple stream communications standard. The communications receiver decodes the received communication signal according to the known single stream communications standard upon determining the received communication includes the signal single stream communication signal.
    Type: Grant
    Filed: June 1, 2012
    Date of Patent: January 21, 2014
    Assignee: Broadcom Corporation
    Inventor: Rohit V. Gaikwad
  • Patent number: 8532600
    Abstract: A system includes a first clock module, a global positioning system (GPS) module, a phase-locked loop (PLL) module, a cellular transceiver, and a baseband module. The first clock module generates a first clock reference. The GPS module operates in response to the first clock reference. The WLAN module operates in response to the first clock reference. The PLL module generates a second clock reference by performing automatic frequency correction (AFC) on the first clock reference in response to an AFC signal. The cellular transceiver receives radio frequency signals from a wireless medium and generates baseband signals in response to the received radio frequency signals. The baseband module receives the baseband signals, operates in response to a selected one of the first clock reference and the second clock reference, and generates the AFC signal in response to the baseband signals.
    Type: Grant
    Filed: October 30, 2012
    Date of Patent: September 10, 2013
    Assignee: Marvell World Trade Ltd.
    Inventors: Gregory Uehara, Alexander Zaslavsky, Brian Brunn
  • Patent number: 8428531
    Abstract: A radio wave receiver including an antenna for receiving a radio wave; a tuning unit that can discretely changing a frequency characteristic of the antenna; an oscillation generator that can oscillate the antenna and a circuit portion of the tuning unit; a reception processing section for extracting a signal of a desired wave out of a reception signal received from the antenna; a controller for generating an oscillation signal at the circuit portion by the oscillation generator, and switching a setting of the tuning unit to search a setting state of the tuning unit under which the oscillation signal is extracted by the reception processing section; and a compensator for applying a variation to a frequency characteristic of the oscillation signal or a frequency characteristic associated with signal extraction of the reception processing section when the controller searches the setting state.
    Type: Grant
    Filed: May 5, 2010
    Date of Patent: April 23, 2013
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 8301098
    Abstract: A system comprises a first clock module configured to generate a first clock reference that is not corrected using automatic frequency correction (AFC). A global position system (GPS) module is configured to receive the first clock reference. An integrated circuit for a cellular transceiver includes a system phase lock loop configured to receive the first clock reference, to perform AFC, and to generate a second clock reference that is AFC corrected.
    Type: Grant
    Filed: June 23, 2010
    Date of Patent: October 30, 2012
    Assignee: Marvell World Trade Ltd.
    Inventors: Gregory Uehara, Alexander Zaslavsky, Brian Brunn
  • Publication number: 20120195239
    Abstract: A signal generator for a transmitter or a receiver for transmitting or receiving RF-signals according to a given communication protocol includes an oscillator and a mismatch compensator. The oscillator is configured to provide a signal generator output signal having a signal generator output frequency and comprises a fine tuning circuit for providing a fine adjustment of the signal generator output frequency based on a fine tuning signal and a coarse tuning circuit for providing a course adjustment of the signal generator output frequency based on a coarse tuning signal.
    Type: Application
    Filed: February 2, 2011
    Publication date: August 2, 2012
    Applicant: Infineon Technologies AG
    Inventors: Alexander Belitzer, Andre Hanke, Boris Kapfelsperger, Volker Thomas, Elmar Wagner
  • Patent number: 8179118
    Abstract: A system and method for performing wide-band spectral analysis of transient signals using a real-time spectrum analyzer (RTSA). A frequency window is selected for RTSA acquisition, the frequency window being narrower in bandwidth than the frequency spectrum of interest. An RTSA is successively tuned to a plurality of different frequencies within the frequency spectrum of interest, where such successive tuning is controlled based on a characteristic of the signal. The RF signal is received, and, for each of the plurality of different frequencies, power data is acquired for the signal in a band centered on the frequency and having a bandwidth equal to that of the frequency window. A representation of the frequency spectrum of interest is then constructed from the power data acquired during the successive tunings of the RTSA.
    Type: Grant
    Filed: November 2, 2006
    Date of Patent: May 15, 2012
    Assignee: Tektronix, Inc.
    Inventor: Kyle L. Bernard
  • Patent number: 8159334
    Abstract: A tangible computer readable medium includes instructions executable by a processor to cause the processor to communicate with a multicast alert server to receive a multicast emergency alert message via a multicast-enabled network of an Internet Protocol television system. The multicast emergency alert message includes data related to a location code and data related to a set-top box action. The computer program further includes instructions to execute the set-top box action when the location code matches location information stored at a set-top box device.
    Type: Grant
    Filed: March 23, 2011
    Date of Patent: April 17, 2012
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: John McClenny, Thomas Webster, Michael Thomas Raftelis
  • Patent number: 8150349
    Abstract: An apparatus and method for audio conversion is provided to upgrade the resolution of transmission frequency of an FM (frequency modulation) transmitter and reduce the size of the FM transmitter by applying frequency coarse tune and fine tune. The apparatus comprises a digital FM modulator, a digital frequency synthesizer, a signal converter, and an analog frequency converter. The digital FM modulator modulates a digital audio input signal into a first digital audio signal. The digital frequency synthesizer converts the first digital audio signal into a second digital audio signal, whose frequency is determined according to a first frequency conversion parameter. The signal converter converts the second digital audio signal into an analog audio signal. The analog frequency converter generates an audio transmission signal with a predetermined frequency according to a second clock signal and the analog audio signal while the second clock signal is generated according to a first clock signal.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: April 3, 2012
    Assignee: MStar Semiconductor, Inc
    Inventor: ShouFang Chen
  • Patent number: 8131237
    Abstract: Disclosed is a radio wave receiving apparatus including: an antenna to receive a radio wave; a tuning member to allow a reception frequency of the antenna to be tuned to an intended frequency, in which tuning member a frequency characteristic is variable; a receiving member to receive a reception signal from the antenna to demodulate a modulation wave; a positive feedback member to perform a positive feedback in a signal path including the tuning member; and a switching member to turn on/off a feedback operation of the positive feedback member.
    Type: Grant
    Filed: June 17, 2009
    Date of Patent: March 6, 2012
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 8068798
    Abstract: A wireless terminal includes an RF transceiver, an auto tuner, and an antenna. When a remote signal is received at the wireless terminal, the auto tuner is adjusted in accordance with the received signal to optimize OTA performance of the wireless terminal. As further remote signals are received by the wireless terminal, the tuner is readjusted. As a user inputs information to be transmitted, the tuner is also readjusted in accordance with the transmission signals to optimize OTA performance of the wireless terminal, and a best compromise between the TX OTA performance and the RX OTA performance is calculated. Current/temperature information may also be obtained for readjusting the tuner.
    Type: Grant
    Filed: September 16, 2008
    Date of Patent: November 29, 2011
    Assignee: Sony Ericsson Mobile Communications AB
    Inventors: Bruce E. Wilcox, Mete Ozkar, Kerrance L. Carpenter
  • Patent number: 7979040
    Abstract: Disclosed herein is a method for adjusting the tuning frequency of a tuning circuit, which is implemented as a parallel circuit of a coil and series circuits Ai each including a capacitor Ci and a switch device Qi (i=one to n, where n denotes an integer at least equal to two), by varying the tuning frequency through control to turn on and off the switch devices Qi in accordance with control data bi, the method for adjusting the tuning frequency of a tuning circuit including the steps of: finding control data bi for a desired tuning frequency from control data bi for a tuning frequency equal to a first frequency and control data bi for a tuning frequency equal to a second frequency; and applying the control data bi found for the desired tuning frequency to the switch devices Qi.
    Type: Grant
    Filed: February 1, 2008
    Date of Patent: July 12, 2011
    Assignee: Sony Corporation
    Inventor: Taiwa Okanobu
  • Patent number: 7936254
    Abstract: A set-top box device is disclosed. The set-top box device includes a processor and a memory device accessible to the processor. The memory device includes instructions to communicate with a multi-cast alert server to receive a multicast emergency alert message. The multicast emergency alert message includes data related to a location code and data related to a set-top box action. The memory device stores location information and includes instructions to execute the set-top box action when the location code matches the location information.
    Type: Grant
    Filed: February 27, 2009
    Date of Patent: May 3, 2011
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: John McClenny, Thomas Webster, Michael Thomas Raftelis
  • Patent number: 7805118
    Abstract: A satellite receiving system (200, 300) and a method for adjusting a satellite receiving system include an input (113); a first oscillator (106) with theoretical frequency (FOSC1) and real frequency (FOSC1?), a first frequency mixer (105) delivering a signal at a first intermediate frequency (F2), a second oscillator (302) with frequency (FOSC2), a second frequency mixer (301) delivering a signal at a second intermediate frequency (FOUT), a microcontroller (202), which controls a real frequency (FVCO) of the second oscillator, and an output (110). An external signal (112) at a determined frequency (F1) is supplied to the input (113). A nominal value (FOSC2) of the frequency of the second oscillator is determined as a function of the input frequency (F1), the theoretical frequency (FOSC1) of the first oscillator and the second intermediate frequency (FOUT). The frequency of the second oscillator is controlled, via the microcontroller, at the determined nominal value.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: September 28, 2010
    Assignee: STMicroelectronics SA
    Inventors: Jean-Yves Couet, Anis Ben Abdallah
  • Publication number: 20100056088
    Abstract: A disclosed method tunes a signal from a channelized spectrum having a predetermined channel spacing. A signal of interest having a predetermined maximum bandwidth is mixed with a local oscillator signal, which has a frequency that is an integer multiple of the channel spacing or one-half of a channel spacing displaced from an integer multiple of the channel spacing. The local oscillator signal is selected to frequency translate the signal of interest to within a near-baseband passband whose lower edge is spaced from DC by at least about the maximum bandwidth of the signal of interest. Problems associated with 1/f noise, DC offsets, and self-mixing products are avoided or substantially diminished. Other methods and systems are also disclosed.
    Type: Application
    Filed: November 9, 2009
    Publication date: March 4, 2010
    Inventor: Edwin A. Suominen
  • Patent number: 7660339
    Abstract: Provided are an apparatus and method for estimating and correcting a frequency offset in a multiband-Orthogonal Frequency Division Multiplexing Ultra-Wideband system using a time frequency hopping.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: February 9, 2010
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Cheol-Ho Shin, Sung-Woo Choi, Sang-In Cho, Kyu-Min Kang, Sang-Sung Choi, Kwang-Roh Park
  • Patent number: 7630686
    Abstract: A radio-frequency signal receiver and its manufacturing method are disclosed. A tuner receives a radio-frequency signal, and a demodulator receives an output signal from the tuner. An error corrector receives an output from the demodulator. A determiner determines whether or not an error rate supplied from the error corrector is not less than a predetermined rate. A controller receives an output from the determiner, and based on the determination, the controller controls a plurality of sections forming the radio-frequency signal receiver. The controller controls selectively one of the plurality of sections, thereby lowering the error rate. A manufacturing method of this receiver makes a memory, coupled to the controller, store a shift-amount of frequency corresponding to an interference signal in a pass-band of a narrow-band filter.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: December 8, 2009
    Assignee: Panasonic Corporation
    Inventors: Junichi Fukutani, Toshihiro Furusawa, Motoyoshi Kitagawa, Masashi Yasuda
  • Patent number: 7616935
    Abstract: A carrier recovery method and apparatus using multiple stages of carrier frequency recovery are disclosed. A receiver uses multiple frequency generation sources to generate carrier signals used to downconvert a received signal. An analog frequency reference having a wide frequency range and coarse frequency resolution is used in conjunction with a digital frequency reference having a narrow frequency range and fine frequency resolution. The multiple carrier signals are multiplied by a received signal to effect a multi-stage downconversion, resulting in a baseband signal. A frequency tracking module measures the residual frequency error present in the baseband signal. The measured residual frequency error is then used to adjust the frequencies of the carrier signals generated by the multiple frequency generation sources.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: November 10, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Ivan Jesus Fernandez-Corbaton, John Smee, Srikant Jayaraman
  • Patent number: 7515036
    Abstract: The present disclosure is directed to a system and method of communicating emergency alerts. In a particular embodiment, the method includes receiving a multicast emergency alert message at a set-top box device via a multicast-enabled network, where the multicast emergency alert message includes data related to a location code and data related to a set-top box action. The method also includes executing the set-top box action when the location code matches location information stored at the set-top box device.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: April 7, 2009
    Assignee: AT&T Intellectual Property I, L.P.
    Inventors: John McClenny, Thomas Webster, Michael Thomas Raftelis
  • Patent number: 7286794
    Abstract: Methods and systems for communicating information via a plurality of different networks are disclosed herein. Aspects of the method may comprise receiving broadcast information in a mobile terminal via a VHF/UHF broadcast communication path. Cellular information in the mobile terminal comprising voice and data may be received via at least one cellular communication path. Reception in the mobile terminal may be switched between reception of the broadcast information via the VHF/UHF broadcast communication path and the cellular information via the at least one cellular communication path based on a preference indicated via the mobile terminal. The preference may be indicated via a software-controlled interface and/or a user-controlled interface. Reception in the mobile terminal may be switched between reception of the broadcast information via the VHF/UHF broadcast communication path and the cellular information via the at least one cellular communication path based on user input.
    Type: Grant
    Filed: December 13, 2004
    Date of Patent: October 23, 2007
    Assignee: Broadcom Corporation
    Inventor: Pieter Van Rooyen
  • Patent number: 7155190
    Abstract: A high frequency sweep generator uses a DDS-PLL method for frequency sweep over wide frequency spans. A digital sweep generator produces a linear ramp signal using DDS techniques that is applied to a coarse tuning port of a high frequency tunable oscillator, such as a YIG tunable oscillator (YTO). A PLL has as inputs an accurate linear swept frequency sinusoid from a DDS and a linear swept frequency output signal from the YTO to produce an error correction signal that is applied to a fine tuning port of the high frequency tunable oscillator. The error correction signal compensates for any non-linearities introduced into the linear swept frequency output signal by the high frequency tunable oscillator.
    Type: Grant
    Filed: February 19, 2004
    Date of Patent: December 26, 2006
    Assignee: Tektronix, Inc.
    Inventor: Lowell A. Rathbun, Jr.
  • Patent number: 7099642
    Abstract: A carrier recovery method and apparatus using multiple stages of carrier frequency recovery are disclosed. A receiver uses multiple frequency generation sources to generate carrier signals used to downconvert a received signal. An analog frequency reference having a wide frequency range and coarse frequency resolution is used in conjunction with a digital frequency reference having a narrow frequency range and fine frequency resolution. The multiple carrier signals are multiplied by a received signal to effect a multi-stage downconversion, resulting in a baseband signal. A frequency tracking module measures the residual frequency error present in the baseband signal. The measured residual frequency error is then used to adjust the frequencies of the carrier signals generated by the multiple frequency generation sources.
    Type: Grant
    Filed: March 29, 2002
    Date of Patent: August 29, 2006
    Assignee: QUALCOMM, Incorporated
    Inventors: Ivan Jesus Fernandez-Corbaton, John Smee, Srikant Jayaraman
  • Patent number: 7076224
    Abstract: A method and device are disclosed for receiving digital television signals by a frequency tuner. The power of the signal is measured after an analog/digital conversion in the frequency tuner, and the gain thereof is controlled on the basis of this power measurement according to a predetermined control law. The power of the analog signal, tapped between an input amplifier stage and a first frequency transposition stage, or immediately after the first frequency transposition stage, is also measured. The measured power is compared with a predetermined power threshold so as to obtain first binary information, and the gain control law is set on the basis of the value of the first binary information.
    Type: Grant
    Filed: December 4, 2002
    Date of Patent: July 11, 2006
    Assignee: STMicroelectronics S.A.
    Inventors: Florence Giry-Cassan, Fran├žois van Zanten
  • Patent number: 7076221
    Abstract: Disclosed herein is a digital automatic fine tuning method and apparatus, which is capable of detecting a difference between a nominal frequency and an intermediate frequency generated in a tuner using a counter, and applying the counted data of the counter as a fine tuning value for the intermediate frequency without using a decoder by controlling the reset and preset operations of the counter that counts the frequency of the intermediate frequency.
    Type: Grant
    Filed: October 30, 2003
    Date of Patent: July 11, 2006
    Assignee: Samsung Electro-Mechanics Co., Ltd
    Inventors: Young Jin Lee, Hyo Seok Kwon, Won Jin Baek, Jin Taek Lee, Hyun Hwan Yoo, Jeong Ki Choi
  • Patent number: 6980775
    Abstract: A radio device requires a tunable transceiver such that the transceiver can be accurately set to a desired frequency. When a signal with known frequency accuracy is being received, an offset detector can determine the frequency offset generated by the transceiver due to improper tuning. An automatic frequency control (AFC) system (100) is comprised of a tunable transceiver, an adaptive detector (102) for comparing an incoming sample from the tunable transceiver to an adaptive maximum deviation threshold for determining if a sample from the tunable transceiver should be used for the direct current (DC) component of the AFC, an offset detector (103) and an AFC control processor (105) for utilizing information from the offset detector to reduce the inaccuracy in frequency by tuning the transceiver towards the received signal frequency. The AFC control processor (105) utilizes one of more threshold levels for defining a maximum correction threshold (311) based upon the desired maximum offset correction.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: December 27, 2005
    Assignee: Motorola, Inc.
    Inventors: Scott Michael Alazraki, Amish Pravinbhai Shah, Jesus Francisco Corretjer
  • Patent number: 6925291
    Abstract: An electronic alignment system for a television signal tuner utilizes first and second controllers for generating respective first and second control signals for respective first and second signal processing circuits of a signal processing arrangement, with the first and second signal processing circuits having respective first and second tunable elements responsive to the respective first and second control signals. A deviation range of the first control signal is higher than a deviation range of the second control signal.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: August 2, 2005
    Assignee: Thomson Licensing S.A.
    Inventor: Michael A. Pugel
  • Patent number: 6879815
    Abstract: A frequency extractor extracts an input frequency of an input signal. The frequency extractor includes a frequency multiplier, first and second filters, a binary circuit and a frequency divider. The frequency multiplier obtains a signal of a multiplied frequency, the multiplied frequency being N times the input frequency, N being an integer greater than 1. The first filter, having a first bandwidth, filters the signal of the multiplied frequency to provide a first filtered signal. The binary circuit binarizes the first filtered signal to a binary signal. The frequency divider divides the binary signal by a factor of N to provide a divided signal. The second filter, having a second bandwidth, filters the divided signal to generate the input frequency in a form of a continuous wave, wherein the second bandwidth is about 1/N times the first bandwidth.
    Type: Grant
    Filed: July 31, 2002
    Date of Patent: April 12, 2005
    Assignee: Hitachi Kokusai Electric Inc.
    Inventors: Manabu Nakamura, Kazuo Akaike
  • Patent number: 6862437
    Abstract: A dual band RF tuning circuit (1) has a first impedance element (4) and a second impedance element (5) between an RF input port (2) and an RF output port (3), tuning being provided by the impedance elements (4, 5) to a first RF signal, and a switching transistor (9) connected to the second impedance element (5) to open circuit the second impedance element (5) for tuning to a second RF signal by the first impedance element (4) alone.
    Type: Grant
    Filed: November 29, 1999
    Date of Patent: March 1, 2005
    Assignee: Tyco Electronics Corporation
    Inventor: Brian Joseph McNamara
  • Patent number: 6750734
    Abstract: A receiver, such as a television receiver, tunes an inductive (“L”) and capacitive (“C”) filter based on a desired frequency. The LC filter includes a plurality of inductors, configured in at least one inductive (“L”) bank, and a plurality of capacitors configured in at least one capacitive (“C”) bank. The inductors are selectively enabled for the LC filter by an N code, and the capacitors are selectively enabled for the LC filter by an M code. The receiver uses a functional comparator to compare offset, capacitive, inductive and frequency values to tune the LC filter. Techniques for tuning the LC filter for operation in the VHF and UHF bands are disclosed.
    Type: Grant
    Filed: October 15, 2002
    Date of Patent: June 15, 2004
    Assignee: Ukom, Inc.
    Inventors: Kimitake Utsunomiya, Takatsugu Kamata
  • Publication number: 20040067741
    Abstract: In communications between a pair of stations using modulated carrier signals, a first station estimates the carrier frequency offset with respect to the second station and transmits signals that are responsive to the estimated carrier frequency offset. The first station may adjust the carrier frequency of the signals it transmits in response to the estimated carrier frequency offset, and/or transmit data to the second station representing the estimated carrier frequency offset. The second station adjusts the carrier frequency of the signals it transmits to the first station, and/or compensates for carrier frequency offset in its processing of received signals, in response to estimated carrier frequency offset data received from the first station.
    Type: Application
    Filed: October 2, 2002
    Publication date: April 8, 2004
    Inventors: Fan Fei, Ming-Ju Ho, Dukhyun Kim, Marcel Johannes Gerhardus Vrijkorte
  • Patent number: 6700629
    Abstract: When adjusting a free-running frequency of a voltage controlled oscillator, the video intermediate frequency processing apparatus receives a VIF-DEFEAT signal to a VIF-AMP to minimize gain of the VIF-AMP, and thereby, the VCO is placed into a free-running state. The VIF-DEFEAT signal is also used to turn off a switch, thereby preventing the detection result such as a weak electric field of a video detection signal by an IF-AGC circuit from being input into an AFT-DEFEAT circuit. Therefore, in an automatic frequency tuning circuit, it is possible to take a free-running frequency of the VCO converted into a direct current from a pad.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: March 2, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hiroki Miyamoto
  • Patent number: 6697128
    Abstract: For optimum videotex data coding, for error-free functioning of so-called descramblers and—not least—for the impression of improved detail resolution on the screen of a television set of displayed pictures, it is known to process the video frequency response by influencing the higher frequency components in the video signal spectrum. According to the invention, adaptation to a video frequency response sought is in each case carried out automatically by means of corresponding shifting of the vision carrier relative to the IF total transmission curve. The respective adaptation for the relevant television channel of the set is effected, in principle, by the addition of a corresponding correction value to the corresponding channel tuning voltage of the tuner.
    Type: Grant
    Filed: November 27, 2000
    Date of Patent: February 24, 2004
    Assignee: Thomson Licensing S.A.
    Inventors: Helmut Sowig, Reinhard Sauter
  • Patent number: 6668160
    Abstract: A radio transmission link between at least one radio transmission device is monitored and at least one radio reception device. Radio transmission links between at least one transmission antenna and one reception antenna are monitored for faults. At least one radio reception device is tuned to the transmission frequency of at least one radio transmission device. The at least one radio transmission device then transmits, during a predetermined time period, a predetermined test signal which is recorded, evaluated and stored as a reference signal in the at least one radio reception device during a predetermined time period. At the start of a test phase, at least one radio transmission device transmits the predetermined test signal. The test signal is compared with the stored reference signal, and an error signal is produced if the comparison result shows that the test signal has changed beyond a predetermined extent with respect to the stored reference signal.
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: December 23, 2003
    Assignee: Lucent Technologies Inc.
    Inventors: Kai Schmitt, Georg Fischer
  • Publication number: 20030203725
    Abstract: A circuit stage such as an input stage is provided for a radio frequency tuner having an input which typically receives a broadband signal comprising many channels. The input stage comprises a low noise amplifier in the form of a long tail pair of transistors and a controllable tail current source. A level detector detects the signal level at the input of the amplifier and controls the tail current source so as to increase the tail current as the signal amplitude rises above a threshold level and so as to keep the tail current fixed when the signal amplitude is below the threshold.
    Type: Application
    Filed: April 29, 2003
    Publication date: October 30, 2003
    Inventors: Nicholas Paul Cowley, Chi Man Kan, Matthew Aitken
  • Patent number: 6400935
    Abstract: An apparatus and method for detecting the presence of a signal component in an arbitrary signal, where the signal component has a desired frequency. The apparatus includes an error signal generator and a detector. The error signal generator has an input for receiving a reference signal having a reference frequency, a second input for receiving the arbitrary signal having the signal component and an output for generating a difference signal dependent upon a difference in frequency between the reference frequency and the desired frequency. The detector has an input for receiving the difference signal and an output for producing a detector signal when the magnitude of the difference signal is greater than a threshold magnitude. The detector signal indicates the presence of the signal component in the arbitrary signal.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: June 4, 2002
    Assignee: Nortel Networks Limited
    Inventor: Robby Gordon Williams