Automatic Gain Control To Improve Strong Signal Handling Patents (Class 455/250.1)
  • Patent number: 9838735
    Abstract: The present technology relates to a reception device, reception method, and program that can prevent erroneous detection of a predetermined signal, such as a P1 signal, included in, for example, a received signal such as DVB-T2. A correlation calculation unit obtains a correlation value between received signals including a predetermined signal in which an original signal and a duplicate signal obtained from a copy of at least a part of the original signal are disposed. An average power calculation unit obtains average power of the received signals. A normalization unit obtains a normalized correlation value obtained by normalizing the correlation value by the average power. The present technology can be applied to a case where a P1 signal being a preamble signal is detected from a received signal such as DVB-T2, for example.
    Type: Grant
    Filed: April 3, 2014
    Date of Patent: December 5, 2017
    Assignee: SONY CORPORATION
    Inventors: Kenichi Kobayashi, Hiroyuki Kamata, Takuya Okamoto
  • Patent number: 9774362
    Abstract: A user device obtains sensor data from sensors included in the user device. A set of current state information is determined based on the sensor data. A tuner code associated with the current state information is identified. Tuning values associated with the tuner code are varied during a training stage to determine an optimized tuner code. One or more antennae of the user device are tuned for communication in accordance with the optimized tuner code.
    Type: Grant
    Filed: November 7, 2014
    Date of Patent: September 26, 2017
    Assignee: Amazon Technologies, Inc.
    Inventors: Rohit Sammeta, Anuj Dron, Peruvemba Ranganathan Sai Ananthanarayanan, Chun Kit Lai, Eswarappa Channabasappa, Namhoon Kim, Dave Kim, Adrian Napoles, Ulf Jan-Ove Mattsson
  • Patent number: 9716521
    Abstract: The gain of an amplifier in a receiver operating in a cellular communication system is controlled by determining one or more gain variability metrics, which are then used to produce first and second threshold values. A frequency difference between a current carrier frequency and a target carrier frequency is ascertained and then compared to the threshold values. Target gain setting production is based on comparison results: If the frequency difference is larger than the first threshold, a full automatic gain control algorithm is performed; if the frequency difference is smaller than the first threshold and larger than the second threshold, an optimized automatic gain control algorithm is performed, wherein the optimized automatic gain control algorithm uses a current gain setting as a starting point; and if the frequency difference is smaller than both the first and second thresholds, the current gain setting is used as the target gain setting.
    Type: Grant
    Filed: August 12, 2015
    Date of Patent: July 25, 2017
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (publ)
    Inventors: Peter Alriksson, Joakim Axmon
  • Patent number: 9008600
    Abstract: A wireless communication receiver includes a first signal processing circuit, a second signal processing circuit, and a detecting circuit. The first signal processing circuit generates a first processed signal by processing a received radio frequency (RF) signal. The second signal processing circuit is coupled to the first signal processing circuit. The detecting circuit monitors a specific signal of the first signal processing circuit and generates at least a control signal to the second signal processing circuit in response to a signal level of the monitored specific signal. The control signal controls the second signal processing circuit to switch from a first operation mode to a second operation mode.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: April 14, 2015
    Assignee: MediaTek Singapore Pte. Ltd.
    Inventors: George Chien, Chi-Yao Yu, Siu-Chuang Ivan Lu, Yen-Horng Chen, Chih-Chun Tang
  • Patent number: 8983418
    Abstract: Techniques and devices are disclosed to provide multi-stage gain control in circuits or devices having two or more stages of signal amplification. A circuit with multi-stage gain control can include amplification stages coupled to receive an input signal and to produce an amplified output signal. Each amplification stage includes an amplifier that is adjustable in gain and a signal detector that is coupled to measure an output signal of the amplifier and to produce a detector signal indicative of a signal strength of the output signal of the amplifier. A gain control circuit is coupled to receive detector signals from the signal detectors in the amplification stages, respectively, and to control gains of the amplifiers of the amplification stages based on respective received detector signals, respectively.
    Type: Grant
    Filed: June 20, 2011
    Date of Patent: March 17, 2015
    Assignee: Broadcom Corporation
    Inventors: Amir Ibrahim, Henrik Tholstrup Jensen, Shahla Khorram, Aminghasem Safarian, Seema Anand
  • Patent number: 8958758
    Abstract: According to one exemplary embodiment, a communication apparatus includes: a measurement module which measures reception power of each field; a determination module which determines whether the reception power is within a range; a calculator which calculates a gain using the reception power if the reception power is not within the range; an adjuster which adjusts a field according to one of an initial gain and the calculated gain; a selector which selects a field length according to the number of field adjustments by the adjuster; and a transmitter which transmits information regarding the field length. When the number of the adjustments is lower than a first threshold value, the selector selects a first value, and when the number of the adjustments is equal to or higher than the first threshold value, the selector selects a second value that is higher than the first value, as the field length.
    Type: Grant
    Filed: December 29, 2011
    Date of Patent: February 17, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tomoya Tandai, Kentaro Taniguchi, Ryoko Matsuo, Takeshi Tomizawa
  • Patent number: 8948322
    Abstract: A system provides closed-loop gain control in a WCDMA mode and open loop control in an EDGE/GSM mode. Gain control is distributed across analog devices and a digital scaler in a wireless receiver. In the WCDMA mode, a loop filter generates an error signal that is forwarded to analog and digital control paths. The analog control path includes a first adder, a programmable hysteresis element, and a lookup table. The analog control signal is responsive to thresholds, which when used in conjunction with a previous gain value determine a new gain value. The digital control path includes a second adder, a programmable delay element, and a converter. A control word is responsive to a difference of the error signal, a calibration value, and the analog control signal. Blocker detection is provided in the WCDMA mode of operation. A controller sets system parameters using a state machine.
    Type: Grant
    Filed: September 16, 2013
    Date of Patent: February 3, 2015
    Assignee: Skyworks Solutions, Inc.
    Inventors: Jaleh Komaili, John E. Vasa, Thomas Obkircher
  • Patent number: 8886148
    Abstract: In a signal-based gain control scheme, one or more gain levels used for processing signals are selected based on characteristics of previously received signals. For example, different gain levels may be used to receive sets of signals whereupon certain characteristics of the received sets of signals are determined. One or more gain levels are then selected based on these characteristics whereby another signal is processed based on the selected gain level(s). In some aspects, the signal-based gain control scheme may be employed to facilitate two-way ranging operations between two devices. For example, leading edge detection may involve determining a characteristic of a received signal, determining a threshold based on the characteristic, and identifying a leading edge associated with the received signal based on the threshold. In some aspects, the signal-based gain control scheme may be employed in an ultra-low power pulse-based communication system (e.g., in ultra-wideband communication devices).
    Type: Grant
    Filed: September 24, 2010
    Date of Patent: November 11, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Petru Cristian Budianu, David Jonathan Julian, Amal Ekbal
  • Patent number: 8861579
    Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
    Type: Grant
    Filed: March 20, 2014
    Date of Patent: October 14, 2014
    Assignee: National Instruments Corporation
    Inventors: Stephen L. Dark, Christopher J. Behnke
  • Patent number: 8849230
    Abstract: A semiconductor device is provided, including an input attenuator configured to receive an antenna signal and to output a first attenuated signal, the first attenuated signal corresponding to the antenna signal attenuated by a first attenuation factor, the input attenuator being further configured to receive a control signal and to select one of a plurality of predetermined attenuation factors as said first attenuation factor depending on the control signal; an analog to digital converter configured to generate an intermediate signal by digitizing the first attenuated signal; and a digital attenuator configured to receive the intermediate signal and to output a second attenuated signal, the second attenuated signal corresponding to the intermediate signal attenuated by a second attenuation factor, the second attenuation factor being set so as to compensate a gain quantization error of the control signal.
    Type: Grant
    Filed: February 2, 2012
    Date of Patent: September 30, 2014
    Assignee: SONY Corporation
    Inventor: Gerd Spalink
  • Patent number: 8830107
    Abstract: A frequency translating analog-to-digital converter for receiving an analog band-pass signal is described. The analog-to-digital converter comprises an adder/input block for receiving the analog band-pass signal and an analog band-pass feedback signal, thereby forming an analog band-pass error signal. The analog-to-digital converter has at least one analog mixer for mixing and down converting the analog band-pass error signal and thus generating a down-converted analog error signal and at least one quantization path for generating at least one digital signal.
    Type: Grant
    Filed: April 16, 2013
    Date of Patent: September 9, 2014
    Inventor: Udo Karthaus
  • Patent number: 8811537
    Abstract: Provided are a receiving apparatus and method for a wireless communication system using multiple antennas. A receiving method for a wireless communication system using multiple paths, the receiving method comprising: receiving signals through a predetermined number of multiple paths; sensing a carrier according to saturation state degrees of the signals, and providing saturation state information; calculating automatic gain components of the received signals by using the received signals and the saturation state information of the received signals; and performing a noise matching process to amplify noises on the predetermined multiple paths according to the automatic gain components during a predetermined period.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: August 19, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Il-Gu Lee, Jung-Bo Son, Je-Hun Lee, Eun-Young Choi, Sok-Kyu Lee
  • Patent number: 8798567
    Abstract: Disclosed herein is a gain control circuit including: an amplifying section configured to amplify an input voltage in such a manner that amplitude of an output voltage at an output terminal is kept constant; an allowable voltage acquirer configured to acquire an allowable voltage of an apparatus connected to the output terminal; a voltage divider configured to divide the output voltage according to a ratio between a maximum voltage of the amplified input voltage and the allowable voltage; and an adjusting section configured to further amplify the amplified input voltage according to the ratio and supply a resulting voltage to the output terminal.
    Type: Grant
    Filed: May 2, 2013
    Date of Patent: August 5, 2014
    Assignee: Sony Corporation
    Inventors: Yusuke Yoneyama, Noboru Sasho, Takeo Tokunaga
  • Patent number: 8774738
    Abstract: Embodiments of the present disclosure provide systems and methods for estimating gain and phase error in a wireless transmitter. Embodiments of the present disclosure provide a gain and phase controller that uses a digital gain and phase estimator to jointly estimate both gain and phase. The forward and feedback signals of a wireless transmitter are digitized using analog to digital (ADC) converters. The digital signals are correlated with each other to dynamically extract gain and phase estimates of the loop. The gain and phase estimates are used to correct gain and phase errors in the wireless transmitter.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: July 8, 2014
    Assignee: Broadcom Corporation
    Inventors: Sriraman Dakshinamurthy, Mohamed Mostafa, Derek Shaeffer, Dennis Pu, Peter Capofreddi
  • Patent number: 8750431
    Abstract: The detector comprises a plurality of detection stages connected to a summator for providing a summation signal as a logarithmic representation of the input signal to a first input of a data slicer and an input of an average filter having an output connected to a second input of the data slicer. The data slicer has a data slicer output for providing an extracted digital data signal in dependence on a comparison of the summation signal and an output signal of the average filter. The average filter receives a first pre-charge voltage and a second pre-charge voltage depending on an output signal of a carrier detector circuit detecting a carrier signal of the input signal.
    Type: Grant
    Filed: February 23, 2009
    Date of Patent: June 10, 2014
    Assignee: Freescale Semiconductor, Inc.
    Inventor: Laurent Gauthier
  • Patent number: 8731005
    Abstract: A radio system and a method for relaying packetized radio signals is disclosed. The radio system and the method provide a calibration of transmit signals. Furthermore the radio system and the method provide a measurement of a transmit power level. The radio system comprises at least one transmit path, a calibration unit, a base band calibration signal generator synchronized to a synchronization unit, at the least one link and a power sensor. A portion of a selected one of coupled transmit signals is forwarded to a power sensor for measuring a power level, wherein the calibration unit is adapted to update a transmit power level of the at least one transmit path in response to the transmit power level of the selected one of the coupled transmit signals.
    Type: Grant
    Filed: October 12, 2009
    Date of Patent: May 20, 2014
    Assignee: Kathrein-Werke KG
    Inventor: Johannes Schlee
  • Patent number: 8731500
    Abstract: A gain control circuit adjusts the signal level of a received signal responsive to the bandwidth a received signal and/or the delay spread of the channel in which the signal has propagated. The bandwidth and delay spread are evaluated to estimate the amount of signal variation that is expected due to fast fading. Adjustments to the signal level are then made to avoid clipping while at the same time ensuring that the dynamic range of a receiver component is efficiently utilized.
    Type: Grant
    Filed: January 29, 2009
    Date of Patent: May 20, 2014
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventors: Leif Wilhelmsson, Jan Celander, Lars Sundström
  • Patent number: 8712358
    Abstract: A system for receiving an analogue signal e includes amplifying and digitizing the signal in order to obtain a digitized signal en, a power inversion module, the module determining an inversion gain g2, this gain being applied to the digitized signal en, an automatic gain control AGC loop adapting the power of the signal e before digitization, the input signal of the AGC loop being a function of the inversion gain g2.
    Type: Grant
    Filed: June 8, 2012
    Date of Patent: April 29, 2014
    Assignee: THALES
    Inventors: Nicolas Martin, Jean-Michel Perre, David Depraz
  • Patent number: 8681846
    Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
    Type: Grant
    Filed: May 3, 2013
    Date of Patent: March 25, 2014
    Assignee: National Instruments Corporation
    Inventors: Stephen L. Dark, Christopher J. Behnke
  • Patent number: 8676140
    Abstract: A system for controlling an RF gain of a receiver that reduces a time taken to maintain an input signal level at an optimum dynamic range is provided. The system includes a tuner that receives a radio frequency (RF) signal and down-converts the RF signal to an intermediate frequency (IF) signal, and a demodulator. The tuner includes a radio frequency programmable gain amplifier (RF_VGA), a filter and an IF programmable gain amplifier (IF_VGA). The demodulator includes an analog to digital converter (ADC), and an Automatic Gain Control (AGC) unit that (i) receives a digital signal and an IF gain of the IF_VGA. The ADC samples a filtered IF signal under oversampling conditions to obtain an oversampled signal that includes an in-band signal and an out-of-band signal. The AGC unit (ii) controls the RF_VGA, the IF_VGA and (iii) measures an RF energy of the RF signal.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: March 18, 2014
    Assignee: Saankhya Labs Private Limited
    Inventors: Subramanian Harish Krishnan, Parag Naik, Abdul Aziz, Subrahmanya Kondageri Shankaraiah
  • Patent number: 8660221
    Abstract: The present invention discloses apparatus and method for fast and robust automatic gain control (AGC). By using the power statistics and/or the amplitude statistics of multiple pairs of signed ADC outputs, the additional gain control can be determined and included in a statistics-aided AGC to successfully complete the AGC function for a received signal having a dynamic range up to 100 dB within a few micro-seconds.
    Type: Grant
    Filed: June 14, 2012
    Date of Patent: February 25, 2014
    Assignee: ISSC Technologies Corp.
    Inventors: Jeng-Hong Chen, Huei-Ming Yang, Chih-Ching Huang
  • Patent number: 8626094
    Abstract: It has now been found that in some transmitter implementations which transmit multiple code channels, for example CDMA transmitters, the observed power for each code channel at the output relative to the other code channels is dependent upon the total transmit power due to non-linearities in the transmitter. Methods and apparatus are provided which use pre-set digital gains or digital gain adjustments to compensate for the non-linearities as a function of total transmit power such that at the output, the desired relative powers are observed.
    Type: Grant
    Filed: January 28, 2013
    Date of Patent: January 7, 2014
    Assignee: BlackBerry Limited
    Inventors: Xin Jin, Qingzhong Jiao, Wen Zhao
  • Patent number: 8606205
    Abstract: A receiving apparatus converges a gain to a target gain even when a fish bone effect signal is included having a low power period in which signal power decreases abruptly compared to average signal power. The receiving apparatus (100) receives a signal including the fish bone effect signal having the low power period (FBE signal period) in which signal power decreases abruptly compared to average signal power. A FBE detecting section (133) detects an FBE signal period of a low power period based on a gain error corresponding to a difference between target power and average signal power of the received signal of the adjusted gain. Further, the gain error correcting section (134) selects a lower value than 1 as a convergence coefficient in the FBE signal period of a low power period, multiplies the gain error with the selected convergence coefficient and corrects the gain error.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: December 10, 2013
    Assignee: Panasonic Corporation
    Inventors: Tomoya Urushihara, Isao Imazeki
  • Patent number: 8571152
    Abstract: The present invention discloses an apparatus and method for power-saving switch on a pair of configurable analog-to-digital converters. The apparatus mainly comprises an antenna, an antenna switch, a zero-IF RF receiver, and a baseband demodulator. By using a first and a second control signal to control the ON/OFF states of a plurality of switches and a plurality of stage units in the configurable analog-to-digital converters, and the third control signal to control the ON/OFF states of a plurality of LNA stages and the gain of a plurality VGAs, the power saving of the analog-to-digital converter is easily achieved.
    Type: Grant
    Filed: May 22, 2012
    Date of Patent: October 29, 2013
    Assignee: ISSC Technologies Corp.
    Inventors: Jeng-Hong Chen, Chin-Chang Chang, Kuang-Hu Huang, Chih-Ching Huang, Che-Kang Sun, Chun-Yuan Huang
  • Patent number: 8565358
    Abstract: A system provides closed-loop gain control in a WCDMA mode and open loop control in an EDGE/GSM mode. Gain control is distributed across analog devices and a digital scaler in a wireless receiver. In the WCDMA mode, a loop filter generates an error signal that is forwarded to analog and digital control paths. The analog control path includes a first adder, a programmable hysteresis element, and a lookup table. The analog control signal is responsive to thresholds, which when used in conjunction with a previous gain value determine a new gain value. The digital control path includes a second adder, a programmable delay element, and a converter. A control word is responsive to a difference of the error signal, a calibration value, and the analog control signal. Blocker detection is provided in the WCDMA mode of operation. A controller sets system parameters using a state machine.
    Type: Grant
    Filed: January 30, 2012
    Date of Patent: October 22, 2013
    Assignee: Skyworks Solutions, Inc.
    Inventors: Jaleh Komaili, John E. Vasa, Thomas Obkircher
  • Patent number: 8532235
    Abstract: An ultra-wideband (UWB) delay and multiply receiver is formed of a receive antenna; a variable gain attenuator connected to the receive antenna; a signal splitter connected to the variable gain attenuator; a multiplier having one input connected to an undelayed signal from the signal splitter and another input connected to a delayed signal from the signal splitter, the delay between the splitter signals being equal to the spacing between pulses from a transmitter whose pulses are being received by the receive antenna; a peak detection circuit connected to the output of the multiplier and connected to the variable gain attenuator to control the variable gain attenuator to maintain a constant amplitude output from the multiplier; and a digital output circuit connected to the output of the multiplier.
    Type: Grant
    Filed: December 15, 2009
    Date of Patent: September 10, 2013
    Assignee: Lawrence Livermore National Security, LLC.
    Inventors: Gregory E. Dallum, Garth C. Pratt, Peter C. Haugen, Carlos E. Romero
  • Patent number: 8521114
    Abstract: Automatic Gain Control AGC circuit comprising a PIN-diode attenuator having an input and an output and a control circuit connected to the attenuator so as to read a signal at the attenuator output. The control circuit is configured to supply a feedback control signal to the attenuator based on an error signal between the signal read at the attenuator output and a reference signal, so as to modulate an attenuation level of said attenuator and maintain a substantially constant power level at the attenuator output. The control circuit particularly comprises at least a resistor and a capacitor which define a time constant of the AGC circuit, so that the AGC circuit features a main pole depending on such time constant and on a voltage of the feedback control signal. The control circuit also comprises a variable gain block, which receives the feedback control signal and which is configured to modulate the main pole proportionally to a variable gain (G) of the gain block.
    Type: Grant
    Filed: February 22, 2008
    Date of Patent: August 27, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventor: Antonio Carugati
  • Patent number: 8514989
    Abstract: Disclosed is a radio frequency (RF) receiver for receiving a communication channel modulated on one or more carrier frequencies. The receiver may include a gain adjustable RF amplifier, a wideband signal power measurement circuit, and control logic. The control logic may be adapted to use outputs of one or more measurement circuits to classify interfering signals based on measured signal power and spectral proximity to the one or more channel carrier frequencies, and to adjust the gain of the radio frequency amplifier based on the classification.
    Type: Grant
    Filed: August 24, 2009
    Date of Patent: August 20, 2013
    Assignee: Siano Mobile Silicon Ltd.
    Inventors: Roy Oren, Noam Lavi
  • Patent number: 8514991
    Abstract: Disclosed is a radio frequency (RF) receiver for receiving a communication channel modulated on one or more carrier frequencies. The receiver may include a gain adjustable RF amplifier, a wideband signal power measurement circuit, and control logic. The control logic may be adapted to use outputs of one or more measurement circuits to classify interfering signals based on measured signal power and spectral proximity to the one or more channel carrier frequencies, and to adjust the gain of the radio frequency amplifier based on the classification.
    Type: Grant
    Filed: June 7, 2012
    Date of Patent: August 20, 2013
    Assignee: Siano Mobile Silicon Ltd.
    Inventors: Roy Oren, Noam Lavi
  • Patent number: 8498366
    Abstract: A system and technique for providing to flexible, programmable frequency estimators and spectrum analyzers that can operate over extremely large bandwidths and yet provide high spectral resolution are described. The system and technique may include a cascaded super-heterodyne apparatus for estimating a frequency and a bandwidth of signals proximate in frequency to a desired signal, a tunable filter coupled to an input of a receiver, and a tuner which receives a signal from said cascaded super-heterodyne apparatus and tunes the filter to filter out unwanted signals from the receiver.
    Type: Grant
    Filed: January 18, 2012
    Date of Patent: July 30, 2013
    Assignee: Massachusetts Institute of Technology
    Inventors: Soumyajit Mandal, Serhii M. Zhak, Rahul Sarpeshkar
  • Patent number: 8493954
    Abstract: A method and an apparatus for reducing Digital-to-Analog Conversion (DAC) bits at a transmitter of a Frequency Division Multiple Access (FDMA) system reduces a number of the bits for conversion so as to save power and reduce the cost of operation. The method can include generating a digital signal gain control value and an analog signal gain control value using subcarrier allocation information, a required Signal to Noise Ratio (SNR), and a Peak to Average Power Ratio (PAPR); controlling a gain of a signal input to a digital-to-analog converter using the digital signal gain control value; converting a digital signal of the controlled gain to an analog signal using the digital-to-analog converter; and restoring an original signal by controlling a gain of a signal output from the digital-to-analog converter using the analog signal gain control value.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: July 23, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jun-Kyu Kang, In-Tae Kang, Jeong-Gil Lee, Bo-Rham Lee, Sang-Min Bae
  • Patent number: 8472573
    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: Grant
    Filed: July 28, 2011
    Date of Patent: June 25, 2013
    Assignee: Starkey Laboratories, Inc.
    Inventor: Jeffrey Paul Solum
  • Patent number: 8446937
    Abstract: Systems and methods for measuring transmitter and/or receiver I/Q impairments are disclosed, including iterative methods for measuring transmitter I/Q impairments using shared local oscillators, iterative methods for measuring transmitter I/Q impairments using intentionally-offset local oscillators, and methods for measuring receiver I/Q impairments. Also disclosed are methods for computing I/Q impairments from a sampled complex signal, methods for computing DC properties of a signal path between the transmitter and receiver, and methods for transforming I/Q impairments through a linear system.
    Type: Grant
    Filed: April 9, 2012
    Date of Patent: May 21, 2013
    Assignee: National Instruments Corporation
    Inventors: Stephen L. Dark, Christopher J. Behnke
  • Patent number: 8428534
    Abstract: Techniques are disclosed relating to radio frequency (RF) power detection. In one embodiment, a power detection unit is disclosed that includes a multiplier circuit configured to receive a first voltage of a voltage differential signal at gates of a first transistor pair and a second voltage of the voltage differential signal at gates of a second transistor pair. The first multiplier is configured to output a current that varies proportionally to a square of a voltage difference between the first and second voltages. In some embodiments, sources of the first transistor pair are coupled to sources of the second transistor pair, and the sources of the second transistor pair are coupled together. In some embodiments, the power detection unit is configured to compensate for mismatched transistors by applying offset voltages to bodies of transistors in the first and second transistor pairs.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 23, 2013
    Assignee: Silicon Laboratories Inc.
    Inventors: Ravi K. Kummaraguntla, Ruifeng Sun
  • Patent number: 8401130
    Abstract: A system and method are provided for automatic gain control (AGC) using an adaptive reference and a threshold. An adaptive reference allows for adjusting the target power based on variations in operating parameters and conditions, such as a change to a modulation schemes which requires a different signal to noise ratio (SNR) to maintain performance. A gain adjustment threshold allows for rapid AGC response while reducing the potential effects of hysterisis. AGC levels may be changed during symbol prefixes or suffixes, and avoided during a data portion of a signal. Embodiments allow for symbol-by symbol AGC changes in OFDM, OFDMA, and TDD systems.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: March 19, 2013
    Assignee: Adaptix, Inc.
    Inventor: Haitao Wang
  • Patent number: 8385862
    Abstract: It has now been found that in some transmitter implementations which transmit multiple code channels, for example CDMA transmitters, the observed power for each code channel at the output relative to the other code channels is dependent upon the total transmit power due to non-linearities in the transmitter. Methods and apparatus are provided which use pre-set digital gains or digital gain adjustments to compensate for the non-linearities as a function of total transmit power such that at the output, the desired relative powers are observed.
    Type: Grant
    Filed: November 30, 2011
    Date of Patent: February 26, 2013
    Assignee: Research In Motion Limited
    Inventors: Xin Jin, Wen Zhao, Qingzhong Jiao
  • Patent number: 8379874
    Abstract: A wireless device and method may comprise, by way of example, a device and method for receiving wireless transmissions which may include locating data, or authorization data or program data, for determining its location from the locating data, or for determining synchronization for program data, or for ticketing, or for a combination thereof. Authorization data and/or locating data and/or other data may be used to authorize reproduction and/or controlling of received program data, and or for controlling the wireless device. Video program data may be delayed by a number of video frames, preferably an integer number, so as to be substantially synchronized with natural sound. The device and method may determine a location for delaying received program data to be substantially in time alignment with natural sound. A ticketing entity may control a ticket and/or and authorization, and/or may control a remote device thereby.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: February 19, 2013
    Inventor: Jeffrey Franklin Simon
  • Patent number: 8358985
    Abstract: A radio wave receiving apparatus is provided with a tuning circuit for bringing a receiving frequency of an antenna tuned in to a frequency of a desired wave, a frequency converting circuit for mixing a local oscillation signal with the signal received through the antenna, thereby converting the received signal into an intermediate frequency signal, a feed back loop including at least a portion of the tuning circuit for feeding back the received signal, a controller for detecting a level of the intermediate frequency signal to change a frequency characteristic of the tuning circuit, thereby obtaining a tuning point corresponding to the desired wave, wherein, the controller brings the feed back loop in operation, thereby changing the frequency characteristic of the tuning circuit, and when two peaks of a level of the received signal are detected while the frequency characteristic of the tuning circuit is changed, the controller selects as a tuning point corresponding to the desired wave a tuning point at which
    Type: Grant
    Filed: January 6, 2010
    Date of Patent: January 22, 2013
    Assignee: Casio Computer Co., Ltd.
    Inventors: Keiichi Nomura, Kaoru Someya
  • Patent number: 8355687
    Abstract: A gain controller for controlling the gain of at least one amplifier in a receiver, the gain controller being arranged to, when the receiver is receiving a signal: for a first period of time, repeatedly determine an indication of the strength of the received signal and adjust the gain of the at least one amplifier in dependence on each indication of signal strength and following the expiry of the first period of time: determine a subsequent indication of the strength of the received signal and make a single adjustment of the gain of the at least one amplifier in dependence on the subsequent indication of signal strength.
    Type: Grant
    Filed: February 26, 2008
    Date of Patent: January 15, 2013
    Assignee: Cambridge Silicon Radio Limited
    Inventor: Roger Wood
  • Patent number: 8351887
    Abstract: Systems and methods which provide a multimode tuner architecture implementing direct frequency conversion are shown. Embodiments provide a highly integrated configuration wherein low noise amplifier, tuner, analog and digital channel filter, and analog demodulator functionality are provided in a single integrated circuit. A LNA of embodiments implements a multi-path configuration with seamless switching to provide desired gain control while meeting noise and linearity design parameters. Embodiments of the invention implement in-phase and quadrature (IQ) equalization and a multimode channelization filter architecture to facilitate the use of direct frequency conversion. Embodiments implement spur avoidance techniques for improving tuner system operation and output using a clock signal generation architecture in which a system clock, sampling clock frequencies, local oscillator (LO) reference clock frequencies, and/or the like are dynamically movable.
    Type: Grant
    Filed: December 7, 2009
    Date of Patent: January 8, 2013
    Assignee: CSR Technology, Inc.
    Inventor: Jan-Michael Stevenson
  • Patent number: 8306162
    Abstract: A method for use in a digital communications receiver for controlling an input signal level (200) into an analog-to-digital converter (ADC) initially receives a sample sequence (201) where a threshold crossing rate is measured as a percentage samples of an input signal that exceed the threshold (203). The error between the measured threshold crossing rate and a desired reference threshold crossing rate is calculated (205) and an error signal is then utilized in a feedback loop to control the receiver gain such that the error is reduced (207).
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: November 6, 2012
    Assignee: Motorola Solutions, Inc.
    Inventors: Robert J. Corke, Daniel G. Prysby
  • Patent number: 8295252
    Abstract: Systems and methodologies are described that provide interlace-based scheduling for control channels in a wireless communication system. One or more control channels for communication between a base station and a mobile terminal in the wireless communication system may be scheduled on one or more frame interlaces in the system based on one or more conditions of each frame interlace in the system. These conditions may include overhead balance between the frame interlaces, processing timeline optimization for the frame interlaces at the scheduling base station, and the desirability of discontinuous transmission (DTX) at a mobile terminal.
    Type: Grant
    Filed: May 17, 2007
    Date of Patent: October 23, 2012
    Assignee: QUALCOMM Incorporated
    Inventors: Alexei Gorokhov, Aamod Khandekar
  • Patent number: 8259878
    Abstract: Provided are apparatus and method for receiving signals in a wireless communication system.
    Type: Grant
    Filed: December 3, 2009
    Date of Patent: September 4, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Chanho Yoon, Hun-Sik Kang, Eun-Young Choi, Sok-Kyu Lee
  • Patent number: 8238860
    Abstract: An IP2 tuning circuit (404, 1004, 1104 and 1404) for tuning the IP2 of a mixer (414 and 415) to minimize second order intermodulation distortion (IMD2) in a receiver (402, 1002, 1102 and 1402) of a transceiver (401, 1001, 1101 and 1401). An operating characteristic of the mixer related to IMD2 is changeable by changing a value of a setting of the mixer. Two tones outside a bandpass of the receiver are injected into the mixer and a calibration tone within the bandpass is produced as a result of IMD2. Alternatively, a DSSS signal is injected into the mixer and the calibration tone is produced at a chip rate of the DSSS signal. The power of the calibration tone is measured at a plurality of values of the settings. Alternatively, a four-level PN DSSS signal of known content is injected into the mixer, and a two-level PN DSSS signal of known content produced therefrom is correlated with a two-level PN DSSS signal of known content produced by a squaring circuit (1468).
    Type: Grant
    Filed: January 23, 2008
    Date of Patent: August 7, 2012
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Charles LeRoy Sobchak, Mahibur Rahman, Manish N. Shah
  • Patent number: 8233093
    Abstract: Disclosed is an automatic video gain control circuit, which includes an analog to digital converter, an envelope detector and an extreme value detector. The analog to digital converter converts an analog video signal to a digital video signal. The envelope detector detects a baseband amplitude signal according to the digital video signal. The extreme value detector generates an extreme value to control RF signal gain.
    Type: Grant
    Filed: March 22, 2007
    Date of Patent: July 31, 2012
    Assignee: MStar Semiconductor, Inc.
    Inventor: Shan-Tsung Wu
  • Patent number: 8224270
    Abstract: Methods, systems, and machine-readable code for optimizing transmit power of a power amplifier using a Vbat monitor are disclosed and may comprise adjusting the gain of gain stages in a transmit path based on a control signal that is a function of a supply voltage signal, among other variables, derived from a supply voltage that may be used to power a transmit path. The supply voltage signal may be received from a power management unit or derived directly from a battery or other supply. The supply voltage signal may be compared to a reference signal, the result of which may be utilized to generate the control signal. The values for the control signals may be determined over a range of supply voltages and stored in a lookup table.
    Type: Grant
    Filed: December 29, 2006
    Date of Patent: July 17, 2012
    Assignee: Broadcom Corporation
    Inventor: Arya Behzad
  • Patent number: 8218693
    Abstract: Various embodiments are disclosed relating to a gain control for a wireless receiver. In an example embodiment, a wireless receiver is provided that may include an analog gain circuit adapted to provide a variable analog gain on a received input signal, an analog to digital converter (ADC) having an input coupled to an output of the analog gain circuit, and a digital gain circuit having an input coupled to an output of the ADC and adapted to provide a variable digital gain on a received digital signal from the ADC. According to an example embodiment, the wireless transceiver may decrease a gain of the analog gain circuit while maintaining a gain of the digital gain circuit substantially constant for a receiver input signal level that increases from a first input signal level up to at least a first test signal level.
    Type: Grant
    Filed: March 9, 2006
    Date of Patent: July 10, 2012
    Assignee: Broadcom Corporation
    Inventor: Hooman Darabi
  • Patent number: 8213891
    Abstract: A gain control apparatus in a receiver of multiband OFDM system includes: an amplifier amplifying a received signal based on a first auto gain control signal; an analog-to-digital converter for converting the amplified signal into a digital signal; band reception signal extractor for extracting a signal of a desired reception band from the converted digital signal for each reception band, and controlling gain of the extracted signal according to a second auto gain control signal; a reception power detector for detecting a reception power value of whole band from the converted digital signal; and a multiband integration baseband processor for generating the first auto gain control signal by using the detected reception power value of the whole band, and generating the second auto gain control signal to be provided to the band reception signal extraction units, resource allocation information for each band and a reception power for each reception band.
    Type: Grant
    Filed: July 22, 2009
    Date of Patent: July 3, 2012
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seong-Min Kim, Byung-Su Kang, Gweon-Do Jo, Jae-Ho Jung, Joon-Hyung Kim, Heon-Kook Kwon, Sung-Jun Lee, Kwang-Chun Lee
  • Patent number: 8169546
    Abstract: A technique for providing stable tracking performance to an AGC loop circuit comprises amplifying a wideband radio frequency signal; detecting signals and blockers adjacent to the radio frequency signal; lowering a gain of the radio frequency signal; mixing a local oscillator signal with the radio frequency signal; shifting a frequency of the radio frequency signal from a radio frequency to an intermediate frequency; continuously varying a gain of the intermediate frequency signal; converting the intermediate frequency signal into a digital output signal; comparing the digital output signal with predefined thresholds comprising an upper threshold and a lower threshold; switching a post mixer amplifier (PMA) to a high gain state when an input of a variable gain amplifier (VGA) is greater than the upper threshold, and switching the PMA to a low gain state when an input of the VGA is lower than the lower threshold.
    Type: Grant
    Filed: February 19, 2008
    Date of Patent: May 1, 2012
    Assignee: Newport Media, Inc.
    Inventors: Xiaoyu Fu, Jun Ma, Waleed M. Younis, Nabil Yousef, Janakan Sivasubramaniam, Edward Youssoufian
  • Patent number: 8145166
    Abstract: An enhanced programmable automatic level control loop comprising an input for receiving an input RF signal; a level modulator, wherein the level modulator receives the input RF signal and a control signal and wherein the level modulator produces a first signal; a mixer that receives the first signal and mixes it with an LO signal to produce a second signal; a programmable attenuator that receives the second signal and produces an output signal; a level detector that monitors RF power of the output signal and produces a DC voltage proportional to the RF power; and wherein the DC voltage is received at a loop amplifier which produces the control signal.
    Type: Grant
    Filed: December 19, 2008
    Date of Patent: March 27, 2012
    Assignee: Anritsu Company
    Inventors: Richard Glenn Barber, Russell A. Brown