Gain Control Patents (Class 455/232.1)
  • Patent number: 7783272
    Abstract: A broadband signal amplifier includes one of more broadband amplifier circuits, each dynamically controlled in response to a total power level of signals applied thereto to reduce linearity in response to a reduction of input signal strength. A filter may couple the output of the broadband amplifier circuits to each other to form a tandem arrangement. Power detectors are connected to detect and provide outputs indicative of the total power levels of the signals applied to respective broadband amplifiers. A control unit is connected to and receives the output from the power detectors and, in response, provides a control signals to the broadband amplifier circuit so as to operate each over portions of their operating characteristic curves that provide only that degree of linearity necessary to limit distortion to a predetermined or dynamically adjustable maximum acceptable level.
    Type: Grant
    Filed: June 29, 2006
    Date of Patent: August 24, 2010
    Assignee: Microtune (Texas), L.P.
    Inventor: Timothy M. Magnusen
  • Patent number: 7783276
    Abstract: A wireless communication system includes: a filter; and a semiconductor chip including a signal processing integrated circuit having an amplifier, wherein a main surface of the semiconductor chip is provided with a plurality of electrode terminals along an edge portion thereof; wherein the amplifier has a transistor including a control electrode, a first electrode through which a signal is outputted, and a second electrode to which a voltage is applied; wherein the control electrode, the first electrode and the second electrode of the transistor are connected to the electrode terminals, respectively; and wherein none of wirings are arranged between the electrode terminals and placements of the control electrode, the first electrode and the second electrode, making space between the electrodes and the electrode terminals narrow.
    Type: Grant
    Filed: May 6, 2008
    Date of Patent: August 24, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Kumiko Takikawa, Satoshi Tanaka, Yoshiyasu Tashiro
  • Patent number: 7774201
    Abstract: A purpose of the present invention is to provide an acoustic apparatus capable of automatically setting a gain which is suitable for both an averaged signal strength of input voice and an instantaneous signal strength thereof, capable of easily recognizing an effect by a user, which is achieved by switching a turn-ON and a turn-OFF of an automatic gain variable operation, and further capable of readily recognizing a change in gain values by the user. The acoustic apparatus is provided with a gain setting unit (20) for setting a gain from an averaged voice strength within a predetermined time period, and another gain setting unit (22) for setting a gain in response to an instantaneous signal strength thereof; and the acoustic apparatus adjusts a signal strength of an audio input signals (Si) based upon a gain “C” obtained by multiplying a gain “A” by another gain “B.
    Type: Grant
    Filed: May 23, 2005
    Date of Patent: August 10, 2010
    Assignee: Panasonic Corporation
    Inventor: Katsushi Yamada
  • Publication number: 20100197261
    Abstract: Methods and apparatus are provided for wireless communications in a mobile electronic device. In one aspect, the mobile electronic device includes an antenna subsystem and a plurality of wireless communications modules. A method may involve supplying RF signals from each of the wireless communications modules to a single unit for manipulating the RF signals; and controlling the unit for manipulating RF signals to connect an RF signal of a selected one of the wireless communications modules to the antenna subsystem. The unit for manipulating RF signals may perform various kinds of RF signal processing or conditioning. Furthermore, the antenna system may include a phased array antenna. Besides portable computers such as laptop, notebook and netbook computers, the same principles are applicable to mobile electronic devices generally, including cellphones for example.
    Type: Application
    Filed: January 22, 2010
    Publication date: August 5, 2010
    Applicant: SIERRA WIRELESS, INC.
    Inventors: Larry J. Zibrik, Trent Punnett, W. Ross Gray, Peter McConnell
  • Patent number: 7769116
    Abstract: Described herein is a method of automatic gain control and simultaneous digital correction of three types of variations in I/Q receivers: gain imbalance, phase imbalance, and DC offset. Three adaptation loops can operate simultaneously and use the output of an analog to digital converter (ADC) as their input, with the output driving digitally controllable analog components. With appropriate knowledge of signal statistics, the algorithm automatically optimally fills the ADC's full input signal range, providing an automatic gain control function and thus maximizing the signal-to-quantization-noise ratio. In so doing, it corrects gain imbalances between I and Q paths, while additional circuitry corrects DC offsets and phase imbalances.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: August 3, 2010
    Assignee: Maxim Integrated Products, Inc.
    Inventors: Agustin Lebron, Konstantin A. Kouznetsov, Mehdi Tavassoli Kilani
  • Patent number: 7761071
    Abstract: In order to provide a variable gain amplifier of enhanced linearity and wide variable gain range, an AM-modulated signal reception circuit in which the noise of an input portion is reduced so as to improve the follow-up characteristic of an AGC circuit, and an AM-modulated signal detection circuit which produces an output precisely corresponding to a peak value envelope, the variable gain amplifier comprises a differential input amplifier which includes transistors T1 and T2 (in FIG. 8) constituting a differential pair, and a constant current circuit Is operating as an absorption current circuit of the transistors T1 and T2, and a variable impedance which is connected between the sources of the respective transistors T1 and T2, wherein the gain of the differential input amplifier is made variable by variably controlling the value of the variable impedance.
    Type: Grant
    Filed: June 5, 2007
    Date of Patent: July 20, 2010
    Assignee: Oki Semiconductor Co., Ltd.
    Inventors: Tokio Miyasita, Junichi Yanagihara, Takashi Taya
  • Patent number: 7760824
    Abstract: An analog baseband circuit includes first and second DC (direct current) offset cancellers and an offset canceller controller. The first DC offset canceller includes a first filter and a first PGA (programmable gain amplifier) with a first gain step for eliminating a first dc component from an input baseband signal. The second DC offset canceller includes a second filter and a second PGA with a second gain step less than the first gain step for eliminating a second dc component from an output of the first DC offset canceller. The offset canceller controller controls the first and second filters to operate in a fast mode when a gain of the first PGA is changed.
    Type: Grant
    Filed: April 20, 2007
    Date of Patent: July 20, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jae-Wan Kim, Young-Jin Kim, Jae-Heon Lee
  • Patent number: 7756499
    Abstract: The receiver comprises a variable gain amplification unit, a mixing unit, a filtering unit, and three compensation unit. Each compensation unit detects powers of the signal amplified in the variable gain amplification unit, the signal down-converted in the mixing unit and the signal filtered in the filtering unit. A gain of the variable gain amplification unit is adjusted based on the powers detected by three compensation units.
    Type: Grant
    Filed: August 22, 2007
    Date of Patent: July 13, 2010
    Assignee: Integrant Technologies Inc.
    Inventors: Bonkee Kim, Bo-Eun Kim
  • Publication number: 20100173599
    Abstract: One embodiment of the present subject matter includes a method of receiving an input signal. The method, in various embodiments, includes detecting a peak of the input signal and detecting an envelope of the input signal. In various embodiments, the peak and envelope are used to identify out-of-band blocking signals and to adjust gain control. The method also includes comparing the peak to a first threshold Tp and comparing the envelope to a second threshold Te. In the method, if the peak is above the first threshold and the envelope is below the second threshold, then ignoring the input signal. If the envelope is above the second threshold, the method includes applying automatic gain control to decode information encoded in the input signal.
    Type: Application
    Filed: December 31, 2009
    Publication date: July 8, 2010
    Applicant: Starkey Laboratories, Inc.
    Inventor: Jeffrey Paul Solum
  • Publication number: 20100167677
    Abstract: A ZIF radio compensation method is disclosed. The ZIF radio compensation method employs high gain setting compensation values, which are reliably calculated for low gain settings, during entry of the radio into a communications network. Once the network entry is complete, these coarse calibration values are refined during times when no interfering signal is present. The ZIF radio compensation method allows a receiver to use no additional circuitry to achieve isolation, for potential cost savings. The ZIF radio compensation method further speeds up initial calibration, allowing the radio to join the communications network more rapidly.
    Type: Application
    Filed: December 29, 2008
    Publication date: July 1, 2010
    Inventor: KEVIN L. KLESENSKI
  • Patent number: 7746964
    Abstract: A signal processing apparatus includes a plurality of equalizer each used for a corresponding frequency band, controller for setting a gain value in each of the plurality of equalizer, and signal processor for processing an input signal by means of the plurality of equalizer. The controller determines a target gain value for each of the plurality of frequency bands, obtains a value of gain leakage from the first frequency band to a second frequency band adjacent to the first frequency band, updates a gain value set for the second frequency band, updates a gain value set for the first frequency band, repeats an update process for updating the gain value for each of the first frequency band and the second frequency band in an alternate manner until the gain value satisfies a predetermined condition, and sets the updated gain value for each of the frequency bands in the corresponding equalizer.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: June 29, 2010
    Assignee: Sony Corporation
    Inventor: Kenji Nakano
  • Patent number: 7746966
    Abstract: The present invention relates to a method for automatic gain control (AGC) before an initial synchronization of a mobile station modem in OFDM system, and an apparatus thereof.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: June 29, 2010
    Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute, KT Corporation, SK Telecom Co., Ltd., KTFreetel Co., Ltd., Hanaro Telecom, Inc.
    Inventors: Yong-Su Lee, Youn-Ok Park, Jun-Woo Kim, Young-Jo Bang
  • Patent number: 7742749
    Abstract: A method for processing signals received (30) by a sound program signal receiver includes a step (42, 44) of adjusting at least one parameter for processing small audio signals obtained from the received signals. It further includes a prior step of dividing a space representing a quality of reception of sound program signals into a plurality of reception zones wherein the sound program signal receiver is likely to be located. The adjustment (42, 44) of the parameter for processing small audio signals is determined on the basis of one of the reception zones wherein the sound program signal receiver is located.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: June 22, 2010
    Assignee: Continental Automotive France
    Inventor: Cyrille Potereau
  • Patent number: 7738847
    Abstract: The circuit arrangement comprises a tuner with a control amplifier and a mixer connected downstream, and an automatic gain control. The automatic gain control contains a weighting filter, which is connected to the output of the mixer, upstream of an intermediate frequency filter, and which supplies the control signal for the control amplifier of the tuner via a detector. The weighting filter has, in particular, a passband, which corresponds to the passband of the intermediate frequency filter and at least partly encompasses at least one or two adjacent program channels. As a result of this, the control amplifier is better tuned under difficult reception conditions, since, by means of the weighting filter, adjacent channels, relative to the passband of the intermediate frequency filter, are also concomitantly included in the control signal.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: June 15, 2010
    Assignee: Thomson Licensing
    Inventors: Stefan Stalf, Veit Armbruster
  • Patent number: 7738605
    Abstract: Methods and apparatus are provided for adjusting receiver gain based on received signal envelope detection. The gain of a received signal is adjusted by obtaining a plurality of samples of the received signal for a given unit interval; determining an amplitude of the received signal based on the samples; and adjusting a receiver gain based on the determined amplitude. The received signal can be sampled, for example, using a plurality of latches. The value of the received signal can then be estimated by evaluating one or more of the latch values. Once the amplitude of the received signal is determined, one or more latches can be positioned at a desired target amplitude and the receiver gain can be adjusted until the amplitude of the received signal is within a desired tolerance of the specified target value.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: June 15, 2010
    Assignee: Agere Systems Inc.
    Inventors: Mohammad S. Mobin, Gregory W. Sheets, Lane A. Smith
  • Patent number: 7738849
    Abstract: An apparatus and method for adapting a power amplifier to a variable load includes comparing the actual output power to the expected output power, modifying a drive signal to the power amplifier, measuring the value of at least one electrical parameter, determining the difference between the measured value and a predetermined value, and periodically adjusting the drive signal according to the difference. The parameters modified include, but are not limited to, the power delivered to the input of the power amplifier, the DC power supply voltage to any stage of the power amplifier, and the current setting bias values.
    Type: Grant
    Filed: October 14, 2005
    Date of Patent: June 15, 2010
    Assignee: Avago Technologies Wireless IP (Singapore) Pte. Ltd.
    Inventors: Michael Louis Frank, John Stephen Kofol
  • Publication number: 20100142661
    Abstract: The present invention relates to a device for gain control and a method for receiving a signal. The device for gain control according to the present invention includes a map interpreter that detects beamforming symbol periods in wireless signals, a power calculator that calculate the average power of the beamforming symbol periods in response to outputs of the map interpreter, a gain calculator that calculates gain control signals on the basis of the output signals of the power calculator, and a switch that outputs gains from the gain control signals, in which the wireless signals are corrected on the basis of the gains.
    Type: Application
    Filed: July 27, 2009
    Publication date: June 10, 2010
    Applicants: ELECTRONICS AND TELECOMMUNICATIIONS RESEARCH INSTITUTE, SAMSUNG ELECTRONICS CO. LTD.
    Inventors: Hoon LEE, Young Jo BANG, Seungjae BAHNG, Youn Ok PARK
  • Patent number: 7734266
    Abstract: An improved radio frequency receiver and method enabling the dynamic range of a radio frequency receiver to be extended are disclosed. In the receiver system, the effective received channel power is a combination of the wanted signal level, the noise floor and any in band spurious signals generated from blocking signals present at the input to the receiver system. When this total effective channel power is known, the front end gain is optimized by adaptively minimizing the total effective channel power. Since the wanted input signal power does not vary with the receiver gain setting, this optimizes the noise figure and input intercept point for the presented input signal conditions.
    Type: Grant
    Filed: February 15, 2007
    Date of Patent: June 8, 2010
    Assignee: Powerwave Technologies, Inc.
    Inventor: Mark Andrew Billsberry
  • Patent number: 7729673
    Abstract: A method and apparatus provide multichannel signal limiting to prevent any channel signal within a multichannel signal from exceeding defined limits, while still preserving the gain and/or amplitude relationships among the individual channel signals. A limiter is configured to calculate a limiting factor as the value needed to prevent a limit violation on the worst-case one of the channel signals, and then commonly apply that limiting factor to the gain control of all channel signals. Thus, the limiter may generate an actual gain value for each channel signal as the product of that channel signal's desired gain value and the current value of the limiting factor. Notably, in multichannel audio signal applications, coordinating gain control across the individual audio channels by use of the commonly applied limiting factor prevents undesirable spatial shifting of the soundstage, e.g., shifting of the stereo image.
    Type: Grant
    Filed: March 3, 2005
    Date of Patent: June 1, 2010
    Assignee: Sony Ericsson Mobile Communications AB
    Inventors: Eric Douglas Romesburg, Stefan Gustavsson
  • Publication number: 20100093298
    Abstract: A radio frequency transceiver (102), including a transmitter (104), a duplexer (108) and a direct-conversion receiver (106) including a mixer (140 and 141). An IIP2 calibration system (170), coupled to the transceiver, includes an IIP2 coefficient estimator (172) for calculating an estimate of second-order distortion intermodulation distortion, and an IIP2 controller (174) for adjusting an IIP2 tuning port of the mixer in the receiver to minimize second-order distortion intermodulation distortion in the receiver that may be caused by the receiver receiving a transmit RF signal leaking through the duplexer.
    Type: Application
    Filed: October 9, 2008
    Publication date: April 15, 2010
    Applicant: Freescale Semiconductor, Inc.
    Inventors: PATRICK PRATT, CHARLES LEROY SOBCHAK
  • Patent number: 7697614
    Abstract: A system (500) and method (400) are presented for calibrating an analog signal path (200) associated with an Ultra Wideband (UWB) receiver (103). The analog signal path includes a plurality of analog gain stages (210, 212-214, 216), a local oscillator mixer stage (211), a compensation stage (218), and a converter stage (219). An information signal includes whitened symbols (306). When a predetermined number of whitened symbols are accumulated for one of a plurality of gain configurations, an arithmetic mean is calculated and used an offset value. The offset value is retrieved whenever the gain configuration is activated and applied at the compensation stage to reduce the offset.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: April 13, 2010
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Bobby L. Barnes, Timothy R. Miller
  • Patent number: 7697911
    Abstract: An SDARS receiver includes an analog front end configured to receive a composite signal. An A/D converter is coupled to the analog front end and converts the signal to a digitized signal. A digital down converter (DDC) is coupled to the A/D converter and down converts the digitized signal to a down converted signal. A demodulator demodulates the down converted signal. The receiver includes a digital automatic gain control (DAGC) coupled to an output of the A/D converter and before the demodulator. An automatic gain controller is coupled to the DAGC for providing an automatic gain control signal.
    Type: Grant
    Filed: December 8, 2006
    Date of Patent: April 13, 2010
    Assignee: Agere Systems Inc.
    Inventors: Yhean-Sen Lai, Robert C. Malkemes, Jie Song, Denis P. Orlando, Inseop Lee
  • Patent number: 7684774
    Abstract: Disclosed herein are systems and methods for recovering a sub-carrier signal from a multiplexed signal having an embedded pilot tone signal. The recovery system includes circuitry for recovering a pilot signal from the received multiplexed signal, for generating a frequency-doubled signal from the recovered pilot signal, and for phase-shifting the frequency-doubled signal by a pre-determined phase difference from the embedded pilot tone signal. Another recovery system includes circuitry for recovering a pilot signal from the received multiplexed signal, for phase-shifting the pilot signal by a pre-determined phase difference from the embedded pilot tone signal, and for generating a frequency-doubled signal from the phase-shifted signal.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: March 23, 2010
    Assignee: Marvell International Ltd.
    Inventors: Chris Cheng-Chieh Lee, Hui-Ling Lou, Jungwon Lee
  • Patent number: 7684760
    Abstract: An apparatus for controlling transmission power of a mobile communication terminal. The apparatus comprises a central processing unit for measuring a power level of a received signal and determining a power amplification mode in response to the measured power level of the received signal and a power preset table, a driver amplifier for amplifying a transmission signal to produce an output signal, the driver amplifier has operating conditions chosen in accordance with the power amplification mode, a voltage converter for outputting a preset voltage value in accordance with the power amplification mode, and a power amplifier for amplifying the output signal of the driver amplifier in response to the outputted preset voltage value.
    Type: Grant
    Filed: February 11, 2005
    Date of Patent: March 23, 2010
    Assignee: LG Electronics Inc.
    Inventor: Soon-Hyeok Kwak
  • Patent number: 7684516
    Abstract: A method and apparatus for improving signal reception in a receiver (100) by performing all-channel and/or on-channel estimations on a received signal so as to predict future RF environments. The prediction is achieved through the use of one or more detector systems (122, 124) positioned to sample and detect predetermined signal metrics of the received signal (103) prior to analog-to-digital conversion (112) and subsequent post-processing (114). Future estimations of the channel condition are thus generated prior to the arrival of the actual samples (115) at a controller section (116). The detectors (122, 124) provide triggers (123, 125) to the controller (116) so that active stages (130) within the receiver (100) can be adjusted and scaled as needed via a serial port interface (SPI) (126) based on signal conditions.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: March 23, 2010
    Assignee: Motorola, Inc.
    Inventors: Raul Salvi, Jerry T. Bolton, Jr., Charles R. Ruelke
  • Patent number: 7684772
    Abstract: A tuner down-converts a Radio Frequency (RF) wireless signal and outputs the converted signal. The tuner compensates for a TOP depending on a temperature and: detects a received signal strength depending on a RF output of the tuner and transmitting the detected strength to a gain control unit; measures an operating temperature of the tuner and transmits the measured temperature value; receives the measured temperature value to compare the received temperature value with a reference TOP value, compensating compensates for the TOP value depending on variation in temperature and outputting outputs the compensated value; and receives the compensated value to control the RF output based on the TOP value and the received signal strength.
    Type: Grant
    Filed: December 16, 2005
    Date of Patent: March 23, 2010
    Assignee: Integrant Technologies Inc.
    Inventors: Junghwan Lee, Bonkee Kim
  • Patent number: 7676206
    Abstract: A radio receiver front-end includes a tunable antenna interface and a low noise amplifying section. The tunable antenna interface is operably coupled to receive a wide bandwidth signal from an antenna, wherein the wide bandwidth signal includes a plurality of channel signals, and wherein the tunable antenna interface is tuned to pass a selected one of the plurality of channel signals substantially unattenuated and to attenuate remaining ones of the plurality of channel signals to produce a filtered wide bandwidth signal. The low noise amplifying section is operably coupled to amplify the filtered wide bandwidth signal to produce a filtered and amplified wide bandwidth signal.
    Type: Grant
    Filed: December 5, 2005
    Date of Patent: March 9, 2010
    Assignee: Sigmatel, Inc.
    Inventors: Lawrence Henry Ragan, Matthew D. Felder, Jingyu Hu, Jamie Joseph Happ, Michael R. May
  • Patent number: 7676207
    Abstract: Digital autonomous AGC for a DVB-H receiver comprises detecting a plurality of RF signals entering a LNA in the DVB-H receiver; detecting a RF transmitter blocker signal occurring at the LNA; and differentiating between a desired RF signal and an undesired RF transmitter blocker signal by varying a differential gain of current through the LNA. A RF servo loop is used for detecting the RF transmitter blocker signal. Logic circuitry of the RF servo loop is integrated with a baseband AGC loop to step control the differential gain of current through the LNA. A RF wideband detector is used for detecting the plurality of RF signals entering the LNA; and sending a voltage output corresponding to voltage levels of the RF signals to a plurality of comparators, wherein each of the plurality of comparators are set at a different programmable voltage threshold level compared with one another.
    Type: Grant
    Filed: March 8, 2006
    Date of Patent: March 9, 2010
    Assignee: Newport Media, Inc.
    Inventors: Aly Ismail, Janakan Sivasubramaniam, Edward Youssoufian, Nabil Yousef, Frank Carr
  • Patent number: 7672654
    Abstract: A receiver has an amplifier for amplifying a TV broadcast signal. A mixer mixes the amplified signal with an oscillation signal corresponding to a channel selection signal and generates a low frequency signal. A bandpass filter generates a signal having an amplitude corresponding to the low frequency signal. Electric field intensity filtering circuits filter the low frequency signal. A subtractor calculates a difference between the output from the filtering circuits and the output from the bandpass filter to generate a difference signal which is negatively fed back signal to the amplifier when an amplitude of the difference signal is larger than a predetermined value. The signal from the filtering circuit is the negative feed back signal when the amplitude of the difference signal is not larger than the predetermined value. An AGC signal corresponding to an electric field intensity of the output from the mixer is inputted to the amplifier.
    Type: Grant
    Filed: June 14, 2006
    Date of Patent: March 2, 2010
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kunio Okada
  • Patent number: 7668522
    Abstract: A wideband combiner includes a core amplifier for receiving first and second pairs of differential input signals and providing a single pair of differential output signals. The pair of differential output signals are a combination of the first and second pair of differential input signals and a signal gain is implemented between the received first and second pairs of differential input signals and the single pair of differential output signals. The core amplifier is configured to provide a gain value between the first and second pairs of differential input signals and the single pair of differential output signals. The signal gain is substantially constant across the frequency bandwidth of the core amplifier. A bandwidth peaking network is coupled to the core amplifier and includes (a) a first coil and a first resistor connected in series and (b) a second coil and a second resistor connected in series.
    Type: Grant
    Filed: August 15, 2006
    Date of Patent: February 23, 2010
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventor: Michael A. Wyatt
  • Publication number: 20100029324
    Abstract: An architecture for a receiver component in a wireless communications system is disclosed—one that supports both zero intermediate frequency (ZIF) and near-zero intermediate frequency (NZIF) operation. The architecture provides a down-conversion segment, and a local oscillator segment operatively associated with the down-conversion segment. An analog-to-digital conversion (ADC) segment is adapted to receive signals from the down-conversion segment and introduce the signals into a digital intermediate frequency (DIF) construct. The DIF construct performs a DC offset compensation or DC residue filtering on NZIF-based signals, and droop or mismatch compensation. Image removal is performed on NZIF-based signals, and DC offset compensation is performed on ZIF-based signals. Compensated signals are amplified to some nominal or desired level, and interpolation filtering of the amplified signals is performed prior to transmission thereof.
    Type: Application
    Filed: July 6, 2009
    Publication date: February 4, 2010
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: Michael L. Brobston, Steven Loh, Seong Eun Kim, Weon Ki Yoon
  • Patent number: 7657241
    Abstract: Techniques are disclosed for compensating for second-order distortion in a wireless communication device. In a zero-intermediate frequency (IF) or low-IF architecture, IM2 distortion generated by the mixer (20) results in undesirable distortion levels in the baseband output signal. A compensation circuit (104) provides a measure of the IM2 distortion current independent of the radio frequency (RF) pathway to generate an IM2 calibration current. The IM2 calibration current is combined with the baseband output signal to thereby eliminate the IM2 currents generated within the RF pathway. In one embodiment, the calibration is provided at the factory during final testing. In alternative embodiment, additional circuitry (156, 158) may be added to the wireless communication device to provide a pathway between the transmitter (150) and the receiver (146). The transmitter signal is provided to the receiver to permit automatic calibration of the unit.
    Type: Grant
    Filed: February 1, 2002
    Date of Patent: February 2, 2010
    Assignee: QUALCOMM, Incorporated
    Inventor: Peter Jivan Shah
  • Patent number: 7657240
    Abstract: An adjustable RF audio receiver and method are provided. The adjustable RF audio receiver includes an RF antenna configured to receive RF audio signals, and a tuner coupled to the RF antenna and configured to decode received RF audio signals. The adjustable RF audio receiver further includes signal processing circuitry coupled to the tuner and configured to determine signal quality characteristics of the signals received by the adjustable RF audio receiver. The signal processing circuitry provides determined signal quality characteristics and identifies an environment in which the RF audio receiver is operating. The signal processing circuitry is configured to adapt how received signals are processed based on the determined environment.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: February 2, 2010
    Assignee: Delphi Technologies, Inc.
    Inventors: Robert Dean Bonesteel, Todd M. Brandenburg
  • Publication number: 20100022211
    Abstract: The invention provides a signal amplifying stage, used in a signal receiver. The signal amplifying stage has: a fixed-gain low noise amplifier (LNA), amplifying an input signal; a variable-gain LNA (VG-LNA) array, amplifying the input signal, including a plurality of parallel VG-LNAs, the VG-LNA array being parallel with the fixed-gain LNA; a variable-gain amplifier (VGA), being in series with the fixed-gain LNA and the VG-LNA array, for amplifying output signals from the fixed-gain LNA and the VG-LNA array to generate an output signal; an attenuator, being in parallel with a combination of the fixed-gain LNA, the VG-LNA array and the VGA, for attenuating the input signal to generate the output signal; and a control loop, coupled to the VGA and the attenuator, for detecting power levels of the output signal to enable and control the fixed-gain LNA, the VG-LNA array, the VGA and the attenuator.
    Type: Application
    Filed: July 22, 2008
    Publication date: January 28, 2010
    Applicant: MaxRise Inc.
    Inventor: Yi-Ti Huang
  • Publication number: 20100022213
    Abstract: A system includes a radio frequency transceiver. A baseband processor includes an automatic gain control module. The automatic gain control module has a gain that changes from and subsequently returns to a predetermined value each time the radio frequency transceiver receives a radio frequency signal. The baseband processor is configured to selectively generate an interrupt signal each time a radio frequency signal is received based on a magnitude of the change in the gain of the automatic gain control module and a length of time in which the gain returns to the predetermined value. A control module is configured to identify a radio frequency signal received by the radio frequency transceiver as a radar signal in response to the baseband processor having generated a plurality of interrupt signals at substantially equal time intervals.
    Type: Application
    Filed: October 5, 2009
    Publication date: January 28, 2010
    Inventors: Milind Kopikare, Hui Yao Lin, James Yee, Chuong Vu
  • Publication number: 20100022212
    Abstract: A radio receiver adapted to alternatively receive data over a communication channel in a first mode and a second mode. The second mode facilitates reception of data at higher data rates than the first mode. The radio receiver comprises a signal-processing unit and a control unit. The signal processing unit is adapted to determine a quality condition of the communication channel. The control unit is adapted to determine, based on the quality condition, whether the communication channel facilitates operation in the second mode and assess at least one configuration condition, one of the at least one configuration condition being that the communication channel is determined to facilitate operation in the second mode. The control unit is further adapted to configure the radio receiver to operate in the second mode when all of at least one configuration condition are fulfilled or to operate in the first mode otherwise. A method for controlling the radio receiver is also disclosed.
    Type: Application
    Filed: July 6, 2007
    Publication date: January 28, 2010
    Inventors: Bengt Lindoff, Anders Wallen
  • Patent number: 7653159
    Abstract: An Automatic Gain Control (AGC) circuit as used in a digital receiver that utilizes a main loop filter that is of a relatively wide bandwidth. A pre-filter, wideband variance is determined from the input digital signal, and a post-filter, narrowband variance is also determined. The wideband and narrowband variances are then compared to determine if the wideband signal power indicates a variance level that is too great to permit normal loop operation. By reapplying this difference in the power levels to the filter output as needed, such as by a scaling operation, the loss in dynamic range is effectively recovered. In a preferred embodiment, an adjustable gain input amplifier feeds an intermediate frequency (IF) signal to an analog-to-digital converter (ADC). The digitized IF signal is then down-converted to a baseband frequency and subjected to digital filtering. A narrowband sample variance (PN) of the digitally filtered (narrowband) data is then determined.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: January 26, 2010
    Assignee: IPR Licensing, Inc.
    Inventors: Mark J. Takatz, Alton S. Keel, Jr., Stefan Haenggi
  • Publication number: 20100014618
    Abstract: When performing switching control of reception modes trading off reception sensitivity against power consumption in a reception environment, the receiving apparatus and control method of the present invention perform state transition without a reception error occurring due to switching control with the aid of a reception mode in which an intermediate reception performance is provided. The present invention is particularly useful to balance the reception performance with the battery duration in a battery-powered, portable receiving terminal such as a television receiver for a mobile terminal.
    Type: Application
    Filed: November 13, 2007
    Publication date: January 21, 2010
    Applicant: Panasonic Corporation
    Inventors: Yasunobu Tsukio, Hiroaki Ozeki
  • Patent number: 7650128
    Abstract: A received low-frequency standard radio wave, which is an amplitude modulation signal, is converted to an intermediate frequency signal Sa, and is output to a detection circuit and an AGC circuit. The detection circuit and AGC circuit generates an RF control signal Sf1 and IF control signal Sf2 from the input intermediate frequency signal Sa, and controls an RF control circuit and IF control circuit by outputting the generated RF control signal Sf1 and IF control signal Sf2 to the RF control circuit and IF control circuit. By this a radio wave reception device can speed up AGC operation.
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: January 19, 2010
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 7643812
    Abstract: A single-path enhanced-algorithm digital automatic gain control (SDAGC) integrated receiver is presented. The SDAGC has a front-end RF/IF reception/processing block and associated RF/IF AGC, which outputs to a single ADC. Output from the ADC is split into two TDM and one COFDM signal pathways, each with a respective DAGC. The TDM DAGCs are controlled according to TDM post-power signals, while the COFDM, DAGC is controlled according to COFDM post- and pre-power signals. An IF Gain Decision block determines the RF/IF gain based upon the respective gains of the TDM and COFDM DAGCs. A Gain Distributor block then distributes the total gain of the system across the RF/IF AGC and the various DAGCs. To save power, the COFDM pathways may be disabled if the COFDM pre-power signal falls below a threshold value.
    Type: Grant
    Filed: September 18, 2006
    Date of Patent: January 5, 2010
    Assignee: Agere Systems Inc.
    Inventor: Yhean-Sen Lai
  • Patent number: 7643805
    Abstract: A variable gain amplifier (VGA) circuit and an automatic gain control (AGC) method thereof are disclosed. The VGA circuit includes an amplifier circuit and an AGC circuit. The amplifier circuit amplifies an input signal to an output signal according to a predetermined gain and the AGC circuit is connected to the amplifier circuit for regulating the predetermined gain. The AGC circuit further includes a peak detector detecting a peak of the output signal, a replica of the peak detector for detecting a peak of a reference signal, and a comparator for comparing the peak of the output signal with the peak of the reference signal to provide a control signal and then providing the control signal to the amplifier circuit to regulate the predetermined gain.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: January 5, 2010
    Assignee: O2Micro International Ltd.
    Inventors: Seeteck Tan, Xiaoyong Luo
  • Patent number: 7640001
    Abstract: A system for filtering a signal includes a plurality of filter modules coupled in series. Each filter module includes a filter and a variable gain element. Each filter is capable of. receiving an input signal, attenuating a portion of the input signal that is outside a passband associated with the filter, and outputting at least a portion of the input signal that is within the passband associated with the filter. Each variable gain element is capable of receiving a control signal and inducing a gain in an output of the filter based on the control signal.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: December 29, 2009
    Assignee: Microtune (Texas), L.P.
    Inventors: Michael D. Womac, Armin G. Deiss, Thomas Leigh Davis, Kim E. Beumer
  • Patent number: 7626459
    Abstract: A first FET is inserted in a series position between a signal input terminal and a signal output terminal, while second and third FETs are inserted in a shunt position respectively between the signal input terminal and a ground terminal and between the signal output terminal and a ground terminal. First and second reference voltage terminals and a control terminal are provided. A first reference voltage and a control voltage are applied to the first FET, while a second reference voltage and a control voltage are applied respectively to the second and third FETs, so that the first, second, and third FETs serve as variable resistors. As such, a gain control circuit is constructed. Further, a first resistor is provided in parallel to the first FET, while second and third resistors are provided respectively in series to the second and third FETs.
    Type: Grant
    Filed: May 29, 2007
    Date of Patent: December 1, 2009
    Assignee: Panasonic Corporation
    Inventors: Masao Nakayama, Tsunehiro Takagi, Masahiko Inamori, Kaname Motoyoshi
  • Patent number: 7620380
    Abstract: A method for adjusting automatic gain control (AGC) of a radio receiver begins when a primary AGC module establishes an AGC setting for the radio receiver to produce a primary AGC setting. The method continues when a supervisory AGC module compares performance of the radio receiver utilizing the primary AGC setting with a plurality of performance thresholds. The method continues with the supervisory AGC module adjusting the primary AGC setting to produce adjusted AGC setting when the performance of the radio receiver utilizing the primary AGC setting compares unfavorable with a first performance threshold of the plurality of performance thresholds. The method continues with the supervisory AGC module overwriting the primary AGC setting with alternative AGC setting when the performance of the radio receiver utilizing the primary AGC setting compares unfavorable with a second performance threshold of the plurality of performance thresholds.
    Type: Grant
    Filed: March 24, 2006
    Date of Patent: November 17, 2009
    Inventors: Jon David Hendrix, Michael R. May
  • Patent number: 7616718
    Abstract: When carrying out a channel compensation of a data symbol, a channel estimation value of the reference symbol of the frame itself and that of a reference symbol of the preceding frame are used. In this event, if an AGC gain at the time of a channel estimation value by a reference symbol of the frame itself is different from that of a frame of the reference symbol of the preceding frame, and if an AGC gain of the reference symbol of the frame itself is the same as that of a data symbol to be subjected to a transmission compensation, then the channel estimation value by the reference symbol of the preceding frame is corrected so as to cancel the difference of the AGC gains, followed by using it for a channel compensation of the data symbol.
    Type: Grant
    Filed: May 23, 2006
    Date of Patent: November 10, 2009
    Assignee: Fujitsu Limited
    Inventor: Tadahiro Sato
  • Patent number: 7613441
    Abstract: A received low-frequency standard radio wave, which is an amplitude modulation signal, is converted to an intermediate frequency signal Sa, and is output to a detection circuit and an AGC circuit. The detection circuit and AGC circuit generates an RF control signal Sf1 and IF control signal Sf2 from the input intermediate frequency signal Sa, and controls an RF control circuit and IF control circuit by outputting the generated RF control signal Sf1 and IF control signal Sf2 to the RF control circuit and IF control circuit. By this a radio wave reception device can speed up AGC operation.
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: November 3, 2009
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 7610022
    Abstract: Apparatus, systems, and methods implementing techniques for filtering signals are described. A filter circuit receives an input signal and produces a corresponding filtered signal. The filter circuit has a transfer function that relates the filtered signal to the input signal. The transfer function includes at least one pole and at least one zero, where at least one of the zeros corresponds to a first frequency, and at least one of the poles corresponds to a second frequency. The apparatus also includes a negative-transconductance circuit that is coupled to the filter circuit and that increases a magnitude of a component of the filtered signal that corresponds to the second frequency.
    Type: Grant
    Filed: March 5, 2004
    Date of Patent: October 27, 2009
    Assignee: Marvell International Ltd.
    Inventors: Swee-Ann Teo, King Chun Tsai, Sang Won Son
  • Patent number: 7610029
    Abstract: An integrated circuit chip include a transmitter configured for transmitting an electromagnetic signal, a receiver configured for receiving an electromagnetic signal, and an amplifier operatively coupled to the receiver. The amplifier includes a plurality of variable-gain Gm-C filter stages connected in series and configured for selectively amplifying frequency components within a frequency bandwidth of the received electromagnetic signal.
    Type: Grant
    Filed: March 31, 2006
    Date of Patent: October 27, 2009
    Assignee: Broadcom Corporation
    Inventor: Qiang Li
  • Patent number: 7603096
    Abstract: An embodiment of a mixer with carrier leakage self-calibrating is disclosed. The mixer comprises a double balanced mixer, a gm stage comprising a first processing unit and a second processing unit, a current duplicating circuit, a capacitor, a controller and a current compensation unit. The current duplicating circuit selects the first processing unit or the second processing unit and duplicates a duplicated current of the selected processing unit to charge the capacitor. The capacitor has a first terminal and a second terminal, wherein the second terminal is grounded and the first terminal receives the duplicated current. The controller determines a charge time of the capacitor to generate a compensation signal, wherein the charge time is the time that the voltage of the capacitor is charged to equal to a reference voltage. The current compensation unit receives the compensation signal to generate a compensation current to the mixer.
    Type: Grant
    Filed: February 16, 2007
    Date of Patent: October 13, 2009
    Assignee: Mediatek Inc.
    Inventors: Yuan-Hung Chung, Jie-Wei Lai
  • Publication number: 20090253456
    Abstract: A portable dual band receiver (D), intended for equipping a mobile equipment, comprises a first antenna (AN1), a second antenna (AN2), a two-states switching means (SW) connected to the first (AN1) and second (AN2) antennas and arranged to deliver either first signals comprised into a first band when it is set into a first state or second signals comprised into a second band when it is set into a second state, at least one low noise amplifier (A1, A2) arranged to amplify the signals delivered by the switching means (SW), a processing means (PM) arranged to process the signals outputted by the low noise amplifier(s) (A1,A2) either in a first mode or in a second mode, and a control means (CM) arranged, when the processing means (PM) works in the second mode, to determine which of the first (AN1) and second (AN2) antennas induces the best reception quality into the processing means (PM), and to set the switching means (SW) in the state which allows it to deliver the signals received by the antenna that it has de
    Type: Application
    Filed: June 12, 2007
    Publication date: October 8, 2009
    Applicant: NXP B.V.
    Inventors: Yeow Teng Toh, Kam Choon Kwong