With Control (e.g., Automatic Gain Control, Automatic Frequency Control, Etc.) Patents (Class 455/136)
  • Patent number: 7949366
    Abstract: A diversity receiver includes a first radio frequency (RF) receiver section receives a first inbound RF signal over a range of frequencies and generates a first amplified RF signal, wherein the first inbound RF signal includes a desired RF signal component and an undesired signal component. A second RF receiver section receives a second inbound RF signal over the range of frequencies and generates a second amplified RF signal, wherein the second inbound RF signal includes the desired signal component and the undesired signal component. A first RF cancellation module generates a desired RF signal from the desired RF signal component while attenuating the undesired signal component, based on the first amplified RF signal and the second amplified RF signal.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: May 24, 2011
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Patent number: 7933369
    Abstract: Provided is an apparatus for automatic gain control (AGC) widely used in a receiver of a wireless communication system. The receiver of a wireless communication system includes: a step variable gain amplifier and an analog variable gain amplifier disposed in the path of a wireless signal and amplifying the wireless signal; an analog gain control unit for generating a gain control voltage for feedback-controlling an amplification value of the analog variable gain amplifier; a digital gain control unit for receiving the control voltage and generating a digital code determining an amplification value of the step variable gain amplifier. The apparatus for AGC constituted as described above can reduce power consumption and the number of devices by efficiently running an AGC loop in an analog domain, and can be embodied at low cost in a structure appropriately controlling the step gain amplifier and the analog gain amplifier.
    Type: Grant
    Filed: December 7, 2006
    Date of Patent: April 26, 2011
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Jang Hong Choi, Seong Do Kim, Hyun Kyu Yu
  • Patent number: 7912158
    Abstract: A satellite navigation device including a flexible radio frequency (RF) receiver is described. The receiver receives a signal that includes at least a first spread-spectrum signal from a first satellite. The receiver has a first channel that includes an analog-to-digital (A/D) converter to sample and quantize the signal and an automatic gain control (AGC) to adjust an amplification of the signal. The A/D converter has a first non-zero quantization threshold magnitude and a second non-zero quantization threshold magnitude. The AGC may adjust a gain in accordance with the first non-zero quantization threshold magnitude. The gain may correspond to a first pre-determined probability of a non-zero sample and the second non-zero quantization threshold magnitude may correspond to a second pre-determined probability of a non-zero sample.
    Type: Grant
    Filed: November 8, 2005
    Date of Patent: March 22, 2011
    Assignee: Navcom Technology, Inc.
    Inventors: Charles R. Cahn, Jerry Eugene Knight
  • Patent number: 7894376
    Abstract: An RF transceiver includes an RF receiver that receives a received signal from an external device, the RF receiver having an AGC module that generates an automatic gain control (AGC) signal based on a strength of the received signal, and a low noise amplifier that amplifies the received signal based on the AGC signal. A processing module generates a transmit power control signal based on the AGC signal. An RF transmitter generates a transmit signal having a selected power level, wherein the selected power level is based on the transmit power control signal.
    Type: Grant
    Filed: August 30, 2007
    Date of Patent: February 22, 2011
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Patent number: 7894782
    Abstract: An RF transceiver includes a plurality of RF receivers for receiving a corresponding one of a plurality of received signals. Each of the plurality of the RF receivers includes an AGC module that generates an automatic gain control (AGC) signal based on the strength of the corresponding one of the plurality of received signals, and a low noise amplifier that amplifies the corresponding one of the plurality of received signals based on the AGC signal. A processing module generates a transmit power control signal based on the AGC signals from each of the plurality of RF receivers. A plurality of RF transmitters each generate a corresponding one of a plurality of transmit signals having a selected power level, wherein the selected power level is based on the transmit power control signal.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: February 22, 2011
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Patent number: 7869777
    Abstract: In RF transceivers, a method and system for a second order input intercept point (IIP2) correction are provided. A DC offset sensor may detect DC offset voltages produced by blocker signals in “I” and “Q” signal component paths in an RF receiver. The DC offset sensor may generate control signals which may be utilized by a first and second injection circuits to generate DC offset currents that compensate for the DC offset voltages in the signal component paths. An injection circuit may utilize current drivers to generate binary weighted currents which may be added together to produce a DC offset current. The polarity of the DC offset current and the selection of which current drivers to use may be determined by the control signals. A calibration voltage may also be utilized to correct or adjust the gain in the injection circuit.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: January 11, 2011
    Assignee: Broadcom Corporation
    Inventor: Hooman Darabi
  • Patent number: 7864887
    Abstract: A symbol clock recovery subsystem uses a tap delay line having a set of delays, uses a clock bank of samplers providing time-staggered sampled noncoherently received signals, and uses a set of mean magnitude generators, in channelized form, for providing a set of mean magnitudes to a maximum selector for selecting a maximum one of the time-staggered sampled received signals having the greatest signal to noise ratio so as to provide a signal effectively occurring at symbol epoch time for demodulating a symbol stream in a digital communication system receiver.
    Type: Grant
    Filed: July 11, 2007
    Date of Patent: January 4, 2011
    Assignee: The Aerospace Corporation
    Inventors: Gee L. Lui, Kuang Tsai
  • Patent number: 7853224
    Abstract: A fast settling AGC system includes a “fast settle” comparator that facilitates fast settling of strong radio receiver output signals from a maximum to an intermediate voltage level at the start of each transmission burst, and a “normal” AGC comparator that further settles the output signal from the intermediate voltage level to a desired target output voltage level at a slower “normal” rate. The gain control signal components generated by both the “fast settle” comparator and the “normal” AGC comparator are summed and applied to the gain control terminal of a variable gain amplifier. The gain control signal component generated by the “fast settle” comparator has a higher current level than the gain control signal component generated by the “normal” comparator, but is terminated when receiver output signal drops to the intermediate voltage level.
    Type: Grant
    Filed: November 2, 2007
    Date of Patent: December 14, 2010
    Assignee: Micrel, Incorporated
    Inventor: George R. Exeter
  • Patent number: 7853228
    Abstract: A signal relay apparatus, method, application program, and computer readable medium adapted for wireless network are capable of saving power consumption due to failure of adjusting amplifying gain dynamically and solving the difficulty of demodulation since noise is also amplified during relay. For wireless access network, the present invention decreases the transmission power of mobile devices so that the battery of the mobile devices may keep working longer and the interference inside is reduced.
    Type: Grant
    Filed: February 22, 2007
    Date of Patent: December 14, 2010
    Assignee: Institute for Information Industry
    Inventors: Chih-Chiang Hsieh, Yi-Hsueh Tsai, Yung-Ting Lee
  • Patent number: 7817976
    Abstract: A method includes a foreground process and a background process. In the foreground process, an input signal is processed using a first reference signal to generate an output. A first frequency control signal is generated from the output. A frequency of the first reference signal is controlled based on the first frequency control signal. In the background process, a foreground processed signal is received from the foreground process. The foreground processed signal is processed using a second reference signal. A second frequency control signal is generated from the foreground processed signal. A frequency of the second reference signal is controlled based on the second frequency control signal so that the background processing step removes effects of the foreground controlling step.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: October 19, 2010
    Assignee: Research In Motion Limited
    Inventors: Sean B. Simmons, Zoltan Kemenczy
  • Patent number: 7809341
    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: April 15, 2009
    Date of Patent: October 5, 2010
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 7787849
    Abstract: An integrated circuit (IC) includes an RF receiver having an AGC module that generates an automatic gain control (AGC) signal based on a strength of a received signal, and a low noise amplifier that amplifies the received signal based on the AGC signal. A processing module generates a power mode signal based on the AGC signal, the power mode signal for adjusting a power consumption parameter of the IC based on the power mode signal.
    Type: Grant
    Filed: August 31, 2007
    Date of Patent: August 31, 2010
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Patent number: 7787850
    Abstract: An integrated circuit (IC) includes a plurality of RF receivers for receiving a corresponding one of a plurality of received signals. Each of the plurality of the RF receivers includes an AGC module that generates an automatic gain control (AGC) signal based on the strength of the corresponding one of the plurality of received signals, and a low noise amplifier that amplifies the corresponding one of the plurality of received signals based on the AGC signal. A processing module generates a power mode signal for adjusting a power consumption parameter of the IC, based on the AGC signals from each of the plurality of RF receivers.
    Type: Grant
    Filed: September 5, 2007
    Date of Patent: August 31, 2010
    Assignee: Broadcom Corporation
    Inventor: Ahmadreza (Reza) Rofougaran
  • Patent number: 7787841
    Abstract: The demodulator in the receiving module of the invention supplies a signal produced based on a signal level detected by a first detector to a second amplifier as an amplification degree adjustment signal. With this arrangement, when a second receiver works, an AGC voltage supplied to the second receiver is already close to an ultimately converging certain value. The AGC voltage supplied to the second receiver is thus stabilized in its value, from the value close to the ultimately converging certain value to the certain value. Accordingly, a time period required from the second receiver starts working until the AGC voltage supplied to second amplifier ultimately converges into the certain value is shortened.
    Type: Grant
    Filed: June 5, 2006
    Date of Patent: August 31, 2010
    Assignee: Panasonic Corporation
    Inventors: Yasunobu Tsukio, Hiroaki Ozeki
  • Patent number: 7778223
    Abstract: Whether the reception electric field level of the antenna #1 is higher than the predetermined level is judged. If the reception electric field level of the antenna #1 is not higher than the predetermined level, the communication mode is to be set to the multi-slot mode, and then whether the reception electric field level of the antenna #1 is higher is judged by comparison of the reception electric field level of the antenna #1 and the reception electric field level of the antenna #2. If the reception electric field level of the antenna #1 is higher, the call mode is to be set to the antenna #1 for executing transmission and reception, or if the reception electric field level of the antenna #1 is not higher, the communication mode is to be set to the antenna #2 for executing transmission and reception.
    Type: Grant
    Filed: December 5, 2006
    Date of Patent: August 17, 2010
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Shinichi Sakakibara
  • 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: 7761055
    Abstract: An antenna (8), mounted to a roof (3) of a building (1), receives digital broadcast transmissions and feeds a signal through a cable (9) to a desk stand (2). The desk stand has an amplifier and a loop antenna. A mobile telephone handset (6) capable of receiving digital broadcast transmissions also includes a loop antenna. Using inductive coupling, the signal is transmitted from the desk stand to the mobile telephone handset.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: July 20, 2010
    Assignee: Nokia Corporation
    Inventors: Kimmo Laiho, Mauri Mäkivuoti
  • Patent number: 7751520
    Abstract: Techniques are disclosed for detecting a packet. One technique includes sampling a received signal to produce a sequence of samples wherein the sequence of samples includes a plurality of subsequences of samples; cross correlating the subsequences of samples with a known form of the subsequence to produce cross correlations; self correlating the cross correlations to produce a plurality of self correlations; summing the self correlations; and processing the sum of the self correlations.
    Type: Grant
    Filed: September 17, 2003
    Date of Patent: July 6, 2010
    Assignee: Atheros Communications, Inc.
    Inventors: Chaohuang Zeng, Jeffrey M. Gilbert, Won-Joon Choi, Xiaoru Zhang
  • Patent number: 7747232
    Abstract: A method and apparatus for operating a radio reception system, which comprises a plurality of receivers assigned to a common output device, in which one of the receivers is designated as audio receiver and is tuned to a frequency of a radio transmitter, and outputs a signal received from the transmitter to the output device. At least one second receiver is designated as search receiver, and continuously searches its own reception frequency band for a frequency of the same transmitter. The system changes to a frequency of this transmitter, which was found by the search receiver, if the quality of the signal received by the audio receiver falls below a certain limit.
    Type: Grant
    Filed: October 6, 2006
    Date of Patent: June 29, 2010
    Assignee: Harman Becker Automotive Systems GmbH
    Inventor: Stefan Gierl
  • Patent number: 7747234
    Abstract: A radio frequency (RF) transceiver integrated circuit (IC) includes a plurality of baseband Tx sections, a plurality of RF Tx sections, a plurality of RF Rx sections, and a plurality of baseband Rx sections. The RF transceiver IC further includes a static digital interface, a dynamic digital interface, and gain control, distribution, and buffering circuitry. Static digital interfaces are operable to receive static gain control commands from a coupled baseband processor. The dynamic digital interface is also operable to receive dynamic gain control commands from the coupled baseband processor. The gain control, distribution, and buffering circuitry is operable to apply the static gain control commands and dynamic gain control commands to at least some of the plurality of baseband Tx sections, the plurality of RF Tx sections, the plurality of RF Rx sections, and the plurality of baseband Rx sections.
    Type: Grant
    Filed: June 28, 2005
    Date of Patent: June 29, 2010
    Assignee: Broadcom Corporation
    Inventor: Arya Reza Behzad
  • Patent number: 7729438
    Abstract: A MIMO wireless system includes a transmitter having a parser that parses a bit stream into multiple spatial data streams and multiple interleavers corresponding to the multiple spatial data streams, where each interleaver interleaves the bits in the corresponding spatial data stream by performing multiple column rotations and row rotation, to increase diversity of the wireless system. The MIMO wireless system also includes a receiver that has deinterleavers that deinterleaves spatial bit streams transmitted by the transmitter.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: June 1, 2010
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Xuemei Ouyang, Huaning Niu, Chiu Ngo
  • Patent number: 7720469
    Abstract: A wireless telecommunication device, a method of frequency calibrating a wireless telecommunication device, and a computer program are provided. The method comprises: receiving a reference radio signal of the wireless telecommunications system; frequency synchronizing the wireless telecommunication device with the reference radio signal by adjusting a control parameter controlling a reference frequency generated by a reference frequency generator; measuring a temperature parameter characterizing the temperature of the reference frequency generator; and generating calibration information for calibrating the wireless telecommunication device on the basis of the control parameter and the temperature parameter.
    Type: Grant
    Filed: December 29, 2005
    Date of Patent: May 18, 2010
    Assignee: Nokia Corporation
    Inventor: Erik Olaf Kerstenbeck
  • Publication number: 20100081403
    Abstract: A RAKE receiver is adapted to receive input from at least a first and a second antenna (104a, 104b). The RAKE receiver comprises a despreading unit (303) adapted to allocate a number (Nf) of despreading fingers to a number of delay positions of a signal which is transmitted over a channel. The RAKE receiver further comprises a delay position selection unit (305) which estimates an antenna correlation (formula 1) between the at least first and second antenna (104a, 104b) and controls the despreading unit (303) according to a first strategy for allocating the number (Nf) of fingers if the antenna correlation (formula 1) is below a predetermined threshold, and according to a second strategy otherwise. The threshold (formula 2) is selected based on at least one of the following: number of available finger in the RAKE receiver (Nf), dispersion of the channel, range of direction of arrivals (??).
    Type: Application
    Filed: February 27, 2008
    Publication date: April 1, 2010
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
    Inventor: Andres Reial
  • Patent number: 7689190
    Abstract: A technique includes generating an analog voltage to control a frequency for an oscillator. The analog signal is converted into a digital signal, and the frequency is controlled in response to the digital signal.
    Type: Grant
    Filed: April 22, 2005
    Date of Patent: March 30, 2010
    Assignee: ST-Ericsson SA
    Inventors: Donald A. Kerth, James P. Maligeorgos, Dylan A. Hester, Lysander Lim, Augusto M. Marques, G. Tyson Tuttle
  • 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: 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: 7684524
    Abstract: An automatic gain control (AGC) method according to the present invention applies an initial gain by a digital AGC circuit in a timeslot is determined using a final calculated gain from the same timeslot in the previous frame together with an offset factor. An erase function is activated for a given data sample block when the number of saturated data samples that are detected within the block exceeds a threshold value. The power measurement made by the AGC circuit and used to update the gain is adjusted based on the number of measured data samples that are saturated. These elements provide a gain limiting function and allows limiting of the dynamic range for further signal processing.
    Type: Grant
    Filed: March 12, 2004
    Date of Patent: March 23, 2010
    Assignee: InterDigital Technology Corporation
    Inventors: John W. Haim, Fryderyk Tyra, Louis J. Guccione, Timothy A. Axness, Donald M. Grieco
  • Publication number: 20100069028
    Abstract: A closed-loop antenna switching method, a reference signal allocating method, and a feedback signal transmitting method for the same are disclosed. Namely, by transmitting a reference signal via the plurality of transmitting antennas via the antenna switching for reference signal transmission for each prescribed multiple period of an antenna selection period, efficient antenna index information can be fed back. By setting an antenna switching period to a prescribed multiple of an antenna selection period, it is able to prevent power loss and data decoding performance degradation. And, the present invention includes transmitting a sounding reference signal (SRS) for each band selection period via at least one of the plurality of transmitting antennas and transmitting at least one data demodulation reference signal (DMRS) between the band selection periods via an antenna for not transmitting data by reference signal transmission antenna switching.
    Type: Application
    Filed: January 21, 2008
    Publication date: March 18, 2010
    Inventors: Jin Soo Choi, Min Seok Oh, Hyung Ho Park, Sung Ho Moon, Eun Jong Lee, Kyu Jin Park, Doo Hyun Sung, Doo Hyun Sung, Jae Hoon Chung
  • Patent number: 7676239
    Abstract: A method for operating a power controller in a wireless communication device is provided that includes generating a power controller output signal using an open loop polar modulation scheme. The power controller output signal is operable to control the power delivered to a high-band power amplifier and a low-band power amplifier. A band state is determined for the wireless communication device. The power controller output signal is provided to the high-band power amplifier when the band state is a high-band state and to the low-band power amplifier when the band state is a low-band state.
    Type: Grant
    Filed: February 24, 2005
    Date of Patent: March 9, 2010
    Assignee: National Semiconductor Corporation
    Inventors: James T. Doyle, Dae Woon Kang
  • Patent number: 7675997
    Abstract: A dynamic DC offset removal apparatus and a dynamic DC offset removal method capable of accurately estimating a change position of a dynamic DC offset and a DC offset value before the change and a DC offset value after the change, thereby carrying out equalization processing on a reception signal whose dynamic DC offsets are removed, and improving a bit error rate characteristic.
    Type: Grant
    Filed: October 6, 2006
    Date of Patent: March 9, 2010
    Assignee: Panasonic Corporation
    Inventors: Tomohiro Yui, Nobuhiro Takagi, Gou Kaise
  • 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: 7668517
    Abstract: The invention provides a radio frequency signal receiver with adequate gain control path to control the gain of a mixer and/or a channel selection filter, comprising a low noise amplifier for receiving and amplifying a radio frequency signal, a local oscillator (LO) for providing a LO signal, a mixer for down converting the radio frequency signal by the LO signal to an intermediate signal, a channel selection filter for receiving and filtering the intermediate signal to develop an output signal, and an automatic gain control unit for feedback adjusting the gain of the low noise amplifier and forward controlling the gain of the mixer and channel selection filter in accordance with the output signal of the low noise amplifier.
    Type: Grant
    Filed: October 6, 2006
    Date of Patent: February 23, 2010
    Assignee: Mediatek Inc.
    Inventor: Tsung-Ling Li
  • Patent number: 7652527
    Abstract: A diversity receiver includes: a plurality of demodulating means for demodulating inputted OFDM signals, to output their demodulated signals; noise component calculating means provided for each demodulating means, for calculating noise components included in the demodulated signals outputted from corresponding demodulating means; channel profile calculating means provided for each demodulating means, for calculating channel profiles based upon the demodulated signals outputted from corresponding demodulating means; transmission channel decision means for determining transmission channel based upon the channel profiles; reliability information generating means for generating reliability information indicating reliability of the demodulated signals outputted from each demodulating means, based upon the noise components and the results of the determinations by the transmission channel decision means; a weighting factor calculating means for calculating, depending on the reliability information, weighting factors
    Type: Grant
    Filed: March 1, 2005
    Date of Patent: January 26, 2010
    Assignee: Mitsubishi Electric Corporation
    Inventors: Jun Ido, Mitsuru Takeuchi
  • 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: 7623896
    Abstract: When power to be transmitted varies, a control section instructs an AGC control section to control a gain of an IQ modulation processing section 6 in accordance with the power. A switch selects a power source voltage, corresponding to the power to be transmitted, from power source voltages V1 to V3 of a wireless module, in accordance with an instruction of the control section, so as to supply thus selected power source voltage to a power amplifier. Thus, it is possible to realize a wireless communication circuit which occupies a less area and consumes smaller amounts of power without narrowing a communication range.
    Type: Grant
    Filed: September 22, 2004
    Date of Patent: November 24, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshiyuki Tanaka, Shinji Hara, Kazuya Oyama, Manabu Omori
  • 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: 7599663
    Abstract: An apparatus comprises a link interface to receive an OFDM symbol from a communications link. A signal-to-noise ratio estimation unit generates an estimate of a geometric signal-to-noise ratio for the received symbol based on a function of the soft and hard decisions. A signal quality of the wireless communications link is based on the geometric signal-to-noise ratio.
    Type: Grant
    Filed: February 2, 2006
    Date of Patent: October 6, 2009
    Assignee: Marvell International Ltd
    Inventor: Ravi Narasimhan
  • Patent number: 7596355
    Abstract: An embodiment of the present invention provides a method of closed loop MIMO calibration in a wireless communication system, comprising detecting that station calibration is obsolete and requires calibration, determining a range of automatic gain control which the station wants to calibrate and determining a list of transmission power for an Access Point (AP) in communication with the station, initiating by the station the calibration by sending the power list and N channel sounding preambles, where N is the number of transmit antennas at the station; and sending back by the AP a channel matrix and L sets of channel sounding preambles with a different transmission power level for each set, where L is the number of entries in the power list.
    Type: Grant
    Filed: November 29, 2004
    Date of Patent: September 29, 2009
    Assignee: Intel Corporation
    Inventors: Qinghua Li, Xintian Lin
  • Patent number: 7593706
    Abstract: A GPS receiver circuit (300) for reducing insertion loss. The receiver circuit (300) includes a switch (304) for diverting input signals between a filtered pathway (312) and a short circuit pathway (310) to an amplifier (314). The amplifier (314) output feeds an automatic gain controller (316) that senses a noise level in the output of the amplifier (314) and adjusts a gain of the amplifier (314) in response to the noise level. The receiver circuit (300) also includes a threshold detector (306) with an input coupled to the output of the automatic gain controller (316) and an output coupled to the switch (304) for selecting between the filtered pathway (312) and the short circuit pathway (310), thereby removing the filter (312) from the signal path if not needed.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: September 22, 2009
    Assignee: Motorola, Inc.
    Inventors: Brian E. Bucknor, Humberto E. Garcia, Roberto Gautier
  • Patent number: 7587183
    Abstract: According to various exemplary embodiments, apparatus, systems, and methods are disclosed for use with antenna systems operable for receiving first and second signals having respective first and second frequencies. In one exemplary embodiment, a controller selectively controls whether an amplifier is electrically powered via a first receiver associated with the first frequency or a second receiver associated with the second frequency depending on whether the first receiver, second receiver, or both are present and activated.
    Type: Grant
    Filed: December 15, 2006
    Date of Patent: September 8, 2009
    Assignee: Laird Technologies, Inc.
    Inventors: Ayman Duzdar, Tan Dinh Quach, Keith J. Schrag
  • Patent number: 7587188
    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: September 8, 2009
    Assignee: Casio Computer Co., Ltd.
    Inventor: Kaoru Someya
  • Patent number: 7567784
    Abstract: A tuner, a broadcast signal processing apparatus and method, which satisfy reception sensitivity of both terrestrial and cable televisions, when selecting a broadcast signal through a single conversion tuner, are provided. A tuner selects a broadcast signal of a selected channel. The tuner includes an input filter that filters a received broadcast signal into plural frequency bands based on a predetermined frequency band. An amplifier amplifies a second signal having an original phase induced by an output signal of the respective frequency bands, and a first signal having an opposite phase of the second signal, and outputs the signal induced by the amplified first and second signals as an amplification signal of the signal in the respective frequency bands. An inter-stage filter filters a frequency of the broadcast signal corresponding to the selected channel among the amplification signals output from the amplifier.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: July 28, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Yong-ho Choi
  • Patent number: 7567815
    Abstract: A communication station needs to autonomously and synchronously operate by maintaining an equal frame interval. A clock error is measured from a received packet in a wireless communication system where a beacon is transmitted periodically. This clock error is used to synchronize a counter to count the beacon's transmission/reception time and adjust a clock cycle deviation for synchronization. The synchronization is possible even in the case of restoration from a sleep state when the reference clock accuracy is poor. A period to maintain the sleep state can be extended irrespectively of the clock accuracy. It is possible to prevent desynchronization due to incorrect synchronization with an abnormal value.
    Type: Grant
    Filed: February 25, 2005
    Date of Patent: July 28, 2009
    Assignee: Sony Corporation
    Inventors: Kenzoh Nishikawa, Kazuyuki Sakoda
  • Patent number: 7565125
    Abstract: A receiver 30 has an adjustable gain control circuit 32 that provides gain control base on the magnitude of the signal at the input of an analog-to-digital converter 22. The magnitude of a gain increase or decrease can be based on the most significant bits of the analog-to-digital output, indicating whether the analog-to-digital converter is close to saturation, approaching saturation, or well below saturation.
    Type: Grant
    Filed: June 23, 2003
    Date of Patent: July 21, 2009
    Assignee: Texas Instruments Incorporated
    Inventors: Pascal Audinot, Vincent Roussel
  • Patent number: 7565121
    Abstract: In a clock noise canceling circuit, a coupler extracts a signal from a clock signal. A filter selects a harmonic component of a preset frequency in the extraction signal from the coupler. A phase shifter phase inverts the harmonic component of the preset frequency from the filter. An AGC amplifier amplifies the phase-inverted harmonic component from the phase shifter. Also, a combiner combines the amplified component from the phase shifter with the clock signal to eliminate the harmonic component of the preset frequency from the clock signal. A power detector detects a power level of the harmonic component of the preset frequency in an output signal of the combiner. Additionally, a controller controls gain of the automatic gain control amplifier based on the power level of the harmonic component detected by the power detector, thereby canceling noises.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: July 21, 2009
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Joo Yul Ko, Hak Sun Kim, Won Tae Choi, Won Wook So
  • Patent number: 7565129
    Abstract: A super-regenerative receiver including a super-regenerative oscillator is disclosed. The super-regenerative receiver includes a super-regenerative oscillator for generating an oscillation signal when receiving driving current exceeding a predetermined critical level. The receiver also includes a bias current controller for generating bias current according to an output of the super-regenerative oscillator, and a pulse width controller for receiving a predetermined clock and controlling a width of the clock according to the output of the super-regenerative oscillator. The super-regenerative receiver further includes a quench generator receiving the width-controlled clock from the pulse width controller and generating quench current that varies according to the pulse width of the clock. The driving current for oscillation equals to a sum of the bias current N-times multiplied and the quench current.
    Type: Grant
    Filed: December 4, 2006
    Date of Patent: July 21, 2009
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Jeong Hoon Kim, Tah Joon Park, Eung Ju Kim, Joong Jin Kim
  • Patent number: 7561859
    Abstract: A wireless communication terminal includes a transmitting unit transmitting data to a wireless base station, a temperature detecting unit detecting a terminal temperature of the inside of the wireless communication terminal, a transmission power detecting unit detecting a transmission power, a memory unit storing plural sets of terminal temperature variation information, and a control unit changing the transmission power based on a state of communication with a wireless base station. The control unit selects and reads one of the plural sets of terminal temperature variation information from a memory unit, based on an ambient temperature, a transmission power, and a changed one of predetermined transmission powers. The control unit controls the transmission state of the data based on the selected one of the plural sets of terminal temperature variation information, so as to prevent the terminal temperature from increasing over an upper limit of a predetermined operation guarantee temperature range.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: July 14, 2009
    Assignee: Kyocera Corporation
    Inventor: Hajime Nagano
  • Patent number: 7546101
    Abstract: Disclosed herein is a system for the variable attenuation of broadband differential signals. An exemplary system of variable attenuation of broadband differential signals includes attenuation devices arranged such that an attenuation device on the positive side of the differential signal has a corresponding attenuation device on the negative side of the differential signal with both of the corresponding attenuation devices on the same semiconductor die.
    Type: Grant
    Filed: April 19, 2006
    Date of Patent: June 9, 2009
    Assignee: Scientific-Atlanta, Inc.
    Inventor: William T. Murphy
  • Patent number: 7539469
    Abstract: A receiver may receive and process broadcasting signals in digital and analog forms. The receiver may include an amplifying input stage, a digital signal processing stage and an analog signal processing stage. The input stage may receive a broadcast signal. The digital signal processing stage may process a received broadcast signal and output a first quality information signal. The analog signal processing stage may process a received analog broadcast signal and outputs a second quality information signal. An evaluation unit may evaluate at least one of the first and second quality information signals and output a control signal to the amplifying input stage.
    Type: Grant
    Filed: December 9, 2005
    Date of Patent: May 26, 2009
    Assignee: Harman Becker Automotive Systems GmbH
    Inventors: Michael Zahm, Achim Ratzel, Stefan Köhler