Modulation Distortion Or Cross Talk Correction Or Elimination Patents (Class 455/295)
  • Patent number: 10852439
    Abstract: The present invention provides a global ionospheric total electron content prediction system based on a spatio-temporal sequence hybrid framework. The prediction system implements computational processing for two types of spatio-temporal sequences, wherein for a stationary spatio-temporal sequence, a STARMA model prediction method is constructed in the present invention; for a non-stationary spatio-temporal sequence, a nonlinear spatio-temporal trend is firstly extracted from the non-stationary spatio-temporal sequence by adopting a ConvLSTM method until the extracted residual passes a stationarity test, and then the electron content is predicted using the STARMA model prediction method.
    Type: Grant
    Filed: July 16, 2020
    Date of Patent: December 1, 2020
    Assignee: BEIHANG UNIVERSITY
    Inventors: Zhipeng Wang, Cheng Wang, Kaiyu Xue, Kun Fang
  • Patent number: 10312959
    Abstract: Provided are a semiconductor device and an operating method thereof. The semiconductor device includes a mode controller configured to output a first control signal in a first communication mode, and output a second control signal in a second communication mode which is different from the first communication mode; and a configurable circuit configured to generate a first output signal to be transmitted to a first type analog-to-digital converter (ADC) in the first communication mode, and generate a second output signal using a second type ADC in the second communication mode, wherein the configurable circuit comprises a switching circuit configured to change a circuit configuration to a first circuit configuration for generating a first output signal in the first communication mode or to a second circuit configuration for generating a second output signal in the second communication mode, depending on the first control signal or the second control signal received from the mode controller.
    Type: Grant
    Filed: March 8, 2017
    Date of Patent: June 4, 2019
    Assignee: Samsung Electronics Co., Ltd
    Inventors: Jong Woo Lee, Jae Hoon Lee, Jong Mi Lee, Thomas Byung Hak Cho
  • Patent number: 9838051
    Abstract: A radio frequency receiver subject to a large in-band interferor employs active cancellation with coarse and at least one fine cancellation signal, each with a respective radio frequency combiner, in order to increase the effective dynamic range of the receiver for weak signals of interest. One or both can be digitally synthesized. This is particularly applicable for co-site interference, whereby the interfering transmit signal is directly accessible. A similar system and method may also be applied to external interferors such as those produced by deliberate or unintentional jamming signals, or by strong multipath signals. An adaptive algorithm may be used for dynamic delay and gain matching. In a preferred embodiment, a hybrid technology hybrid temperature system incorporates both superconducting and semiconducting components to achieve enhanced broadband performance.
    Type: Grant
    Filed: April 11, 2016
    Date of Patent: December 5, 2017
    Inventors: Deepnarayan Gupta, Amol Inamdar
  • Patent number: 9762307
    Abstract: A communication system includes a plurality of base stations and a plurality of communication terminals. The communication terminal calculates a desired channel matrix based on the reference signal received from the desired base station in communication therewith, also calculates an interference channel matrix based on the reference signal received from the strong interference base station having the strongest power of an interference wave affecting the communication terminal, and notifies the desired base station of the desired channel matrix and the interference channel matrix in an uplink message.
    Type: Grant
    Filed: April 15, 2014
    Date of Patent: September 12, 2017
    Assignee: KYOCERA CORPORATION
    Inventor: Toru Sahara
  • Patent number: 9729178
    Abstract: A method, apparatus and receiver for detecting intermodulation distortion (IMD) affecting a received signal in a wireless receiver are provided. One method includes determining a measurement indicative of IMD based on at least one transmit signal. When the measurement indicative of IMD exceeds a first pre-determined level, at least one sample of an amplitude of a signal output by the wireless receiver is collected in a first data set. When the measurement indicative of intermodulation distortion does not exceed a second pre-determined level, the second predetermined level being less than the first predetermined level, at least one sample of an amplitude of the signal output by the wireless receiver is collected in a second data set. A comparison is performed based on data of the first data set and on data of the second data set to determine a measure of IMD.
    Type: Grant
    Filed: April 15, 2016
    Date of Patent: August 8, 2017
    Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
    Inventor: Mark William Wyville
  • Patent number: 9520955
    Abstract: Embodiments of the present invention provide a detection method including receiving a modulated signal data stream from a microwave transmit end, performing amplification on the modulated signal data stream according to an amplification control signal, where the amplification control signal is used to indicate the number of amplification times for the amplification performed on the modulated signal data stream, performing analog-to-digital conversion on the amplified modulated signal data stream to obtain a first digital signal data stream; filtering the first digital signal data stream, performing power detection on the first digital signal data stream to obtain a first average power value, performing power detection on a filtered first digital signal data stream to obtain a second average power value, obtaining the amplification control signal according to the first average power value, and obtaining an RSSI value by calculation according to the amplification control signal and the second average power valu
    Type: Grant
    Filed: June 5, 2015
    Date of Patent: December 13, 2016
    Assignee: Huawei Technologies Co, Ltd.
    Inventor: Hai Li
  • Patent number: 9438285
    Abstract: A method, apparatus and receiver for detecting intermodulation distortion (IMD) affecting a received signal in a wireless receiver are provided. One method includes determining a measurement indicative of IMD based on at least one transmit signal. When the measurement indicative of IMD exceeds a first pre-determined level, at least one sample of an amplitude of a signal output by the wireless receiver is collected in a first data set. When the measurement indicative of intermodulation distortion does not exceed a second pre-determined level, the second predetermined level being less than the first predetermined level, at least one sample of an amplitude of the signal output by the wireless receiver is collected in a second data set. A comparison is performed based on data of the first data set and on data of the second data set to determine a measure of IMD.
    Type: Grant
    Filed: May 1, 2014
    Date of Patent: September 6, 2016
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Mark William Wyville
  • Patent number: 9331728
    Abstract: Methods and circuits for reducing power dissipation in wireless transceivers and other electronic circuits and systems. Embodiments of the present invention use bias current reduction, impedance scaling, and gain changes either separately or in combination to reduce power dissipation. For example, bias currents are reduced in response to a need for reduced signal handling capability, impedances are scaled thus reducing required drive and other bias currents in response to a strong received signal, or gain is increased and impedances are scaled in response to a low received signal in the presence of no or weak interfering signals.
    Type: Grant
    Filed: December 27, 2005
    Date of Patent: May 3, 2016
    Assignee: Theta IP, LLC
    Inventor: Yannis Tsividis
  • Patent number: 9252746
    Abstract: A control device of a receiving device includes an interference wave detector that detects an interference wave within an intermediate frequency band in a signal converted by a mixer that converts a reception signal of a radio frequency band with a certain radio frequency as a center into an intermediate signal of the intermediate frequency band based on a signal of a local oscillation frequency different from the radio frequency. The control device further includes a frequency controller that changes the local oscillation frequency so that the intermediate frequency band gets away from a band of the interference wave when the interference wave is detected.
    Type: Grant
    Filed: January 31, 2014
    Date of Patent: February 2, 2016
    Assignee: FUJITSU LIMITED
    Inventors: Yusuke Suzuki, Hideyuki Kannari, Hiroyuki Sekino
  • Patent number: 9143706
    Abstract: An imaging system includes an image detector for producing a continuous image signal from an image received thereat; oscillation means coupled to the image detector for inducing a spatial oscillation in the image relative to the image detector; and a spatio-temporally matching filter in communication with the image detector and the oscillation means. The matching filter is configured to filter out aspects of the image signal not associated with the induced oscillation, to thereby provide enhanced image processing of the image.
    Type: Grant
    Filed: September 21, 2009
    Date of Patent: September 22, 2015
    Inventor: Andrew Zador
  • Patent number: 9129610
    Abstract: Processing a signal includes: receiving data that includes an input signal; filtering the input signal to generate a filtered signal, such that if the input signal includes at least one instance of a nonlinear distortion of a desired signal then the filtered signal includes a signature signal corresponding to the nonlinear distortion, the nonlinear distortion characterized by a time duration that is within a predetermined range; and detecting whether or not the filtered signal includes the signature signal.
    Type: Grant
    Filed: August 21, 2012
    Date of Patent: September 8, 2015
    Assignee: Bose Corporation
    Inventors: James Mulvey, Joseph Gaalaas
  • Patent number: 9100122
    Abstract: Systems and methods are disclosed to analyze and predict the interference susceptibility of receiver designs. In some implementations, the systems and methods may be used during a receiver design phase to predict how well a receiver design will perform in the presence of certain types of signals in a deployment region of a receiver. The systems and methods may allow potential shortcomings in a receiver design affecting interference susceptibility to be identified and remedied before any actual receiver hardware is constructed, thereby reducing costs typically associated with complex hardware redesign efforts.
    Type: Grant
    Filed: May 18, 2012
    Date of Patent: August 4, 2015
    Assignee: Raytheon Company
    Inventors: John H. VanPatten, William H. Davis
  • Patent number: 9042855
    Abstract: Devices and methods capable of correcting for distortion are disclosed. For example, a method for compensating for non-idealities in a frequency-conversion circuit having a high-frequency input side separated from a baseband side by a passive mixer is presented. The method includes injecting a plurality of calibration signals in the baseband side to determine cross-talk between an In-phase (I) portion of the baseband side and a Quadrature (Q) portion of the baseband side to produce a first measurement ?+ and a second measurement ??, synthesizing a crosstalk compensation filter g(?) based on the first measurement ?+ and the second measurement ??, and applying the crosstalk compensation filter g(?) to an output of the frequency-conversion circuit.
    Type: Grant
    Filed: February 11, 2014
    Date of Patent: May 26, 2015
    Assignee: MARVELL INTERNATIONAL LTD.
    Inventors: Daniele Ottini, Alberto Pirola, Paolo Rossi, Marco Sosio, Antonio Liscidini, Rinaldo Castello
  • Patent number: 9037106
    Abstract: A circuit for baseband harmonic rejection includes multiple transconductance cells coupled to one another at outputs of the transconductance cells and configured to receive down-converted signals that vary from one another to produce a weighted current signal proportional to a voltage corresponding to a respective down-converted signal. The circuit also includes a feedback impedance coupled between an input of one of the transconductance cells and the outputs of the transconductance cells. Each of the transconductance cells has an effective transconductance of a first magnitude for frequency components of the down-converted signal arising from a first harmonic and an effective transconductance of a second magnitude less than the first magnitude for frequency components of the down-converted signal arising from harmonics at integer multiples of the first harmonic.
    Type: Grant
    Filed: January 4, 2013
    Date of Patent: May 19, 2015
    Assignee: Broadcom Corporation
    Inventors: David Murphy, Hooman Darabi
  • Publication number: 20150111515
    Abstract: A method in a base station is provided for reducing distortion of an uplink signal received in a receiver part (20) of the base station, said distortion being caused by intermodulation, IM, products. The method comprises: generating (106), from a transmitter source signal, a modeled signal of IM components, as nth order IM components of the transmitter source signal, n being an integer value of 2, 3, 4 and/or 5 etc., and detecting (110) IM products of the received uplink signal, the received uplink signal comprising UL traffic components and the IM products, by correlating the received uplink signal with the IM components of the modeled signal. The method further comprises producing (112) a cancellation signal based on the detected IM products of the received uplink signal, and subtracting (114) the cancellation signal from the received uplink signal. Also, a similar apparatus in a base station is provided.
    Type: Application
    Filed: May 24, 2012
    Publication date: April 23, 2015
    Applicant: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Youping Su, Alireza Nejatian, Fredrik Huss
  • Patent number: 9014651
    Abstract: Embodiments of the present disclosure provide a novel multi-mode platform architecture with means for reducing the interference due to both out-of-band (OOB) emissions and inter-modulation distortion (IMD) products caused by a first radio access technology (RAT) transmitter on a co-located second RAT receiver. The multi-mode platform architecture may be used in a variety of wireless devices and with a variety of co-located RATs, including, without limitation, WiFi, LTE, WiMAX, WCDMA, Bluetooth, and Zigbee, for example.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: April 21, 2015
    Assignee: Broadcom Corporation
    Inventors: Djordje Tujkovic, Louay Jalloul
  • Patent number: 9014124
    Abstract: A wireless transmit/receive unit (WTRU) is described. The WTRU includes a front-end unit (FEU), a signal processing unit (SPU), and a resource management unit (RMU). The FEU receives a radio frequency (RF) signal, generates time-interleaved samples, an includes: a first array of first time-interleaved samplers, a second array of second time-interleaved samplers, and a third array of third time-interleaved samplers. The SPU receives and combines the plurality of time-interleaved samples and generates a signal quality measurement and in-phase and quadrature-phase (IQ) complex samples. The RMU receives the signal quality measurement and allocates FEU resources in conjunction with a front-end unit controller (FEUC) based on the signal quality measurement. The FEUC generates control signals based on the received signal quality measurement from the RMU.
    Type: Grant
    Filed: September 9, 2013
    Date of Patent: April 21, 2015
    Assignee: InterDigital Patent Holdings, Inc.
    Inventors: Tanbir Haque, Leonid Kazakevich, Scott M. Newton
  • Patent number: 9007131
    Abstract: A frequency-control circuit includes a phase frequency detector configured to receive a reference frequency signal and generate an output detection signal. The phase frequency detector can be configured to detect a difference in phase and frequency between the reference frequency signal and a feedback of the output frequency signal. The frequency-control circuit also includes a frequency divider that is configured to apply a correction voltage to a feedback of the output frequency signal, the correction voltage being a function of a pulling signal having one or more unwanted frequency components. The frequency-control circuit also includes a loop filter configured to filter the output detection signal including the correction voltage and generate a control voltage signal. The frequency-control circuit also includes a voltage-controlled oscillator configured to receive the control voltage signal and generate an output frequency signal.
    Type: Grant
    Filed: March 13, 2013
    Date of Patent: April 14, 2015
    Assignee: Broadcom Corporation
    Inventors: Ahmad Mirzaei, Hooman Darabi
  • Patent number: 9002310
    Abstract: Some embodiments of the present disclosure relate to improved techniques for performing IP2 calibration in receivers having two complementary data paths (e.g., i-data path and q-data path). In these techniques, one of the two data paths (e.g., the i-data path) is used to generate a reference signal for the other data path (e.g., the q-data path), and/or vice versa. The other data path then performs calibration using the reference signal. Compared to previous techniques (which required separate, dedicated circuitry for generating a reference signal), the inventive techniques reduce the amount of circuitry and correspondingly reduce the manufacturing costs and power consumption. This is because the inventive techniques use the existing circuitry in complementary fashion during calibration (e.g., during calibration an i-data path generates a reference signal for a q-data path, and vice versa).
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: April 7, 2015
    Assignee: Intel Mobile Communications GmbH
    Inventors: Krzysztof DufrĂȘne, Harald Froehlich
  • Patent number: 8995944
    Abstract: A radio frequency (RF) switch adapted to reduce third order intermodulation (IM3) products generated as RF signals propagate through the RF switch is disclosed. The RF switch includes N semiconductor switch segments, and N?1 phase shift networks, individual ones of the N?1 phase shift networks being coupled between adjacent ones of the N semiconductor switch segments where N is a natural number greater than 1. In operation, when the RF switch is on, IM3 products generated by the RF switch propagating through the N?1 phase shift networks are phase shifted such that the IM3 products are at least partially canceled.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: March 31, 2015
    Assignee: RF Micro Devices, Inc.
    Inventor: Joshua J. Caron
  • Patent number: 8976847
    Abstract: A communications system provides a first communications device, which is connected via a bidirectional transmission channel to a second communications device, wherein the communications devices each comprise a data reconstruction unit. Each communications device comprises a control unit, which is provided for a configuration of various transmission parameters such as modulation type and/or code rate and/or transmitter power and/or size of data packets dependent upon a reliability value evaluated within the control unit. The reliability value indicates a probability for a reliability or a quality of a data reconstruction, which reconstructs transmitted data from received signals within the data reconstruction unit.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: March 10, 2015
    Assignee: Rohde & Schwarz GmbH & Co. KG
    Inventors: Henrik Schober, Torsten Langguth
  • Patent number: 8977223
    Abstract: A radio frequency receiver subject to a large in-band interferor employs active cancellation with coarse and at least one cancellation signals, each with a respective radio frequency combiner, in order to increase the effective dynamic range of the receiver for weak signals of interest. One or both can be digitally synthesized. This is particularly applicable for co-site interference, whereby the interfering transmit signal is directly accessible. A similar system and method may also be applied to external interferors such as those produced by deliberate or unintentional jamming signals, or by strong multipath signals. An adaptive algorithm may be used for dynamic delay and gain matching. In a preferred embodiment, a hybrid technology hybrid temperature system incorporates both superconducting and semiconducting components to achieve enhanced broadband performance.
    Type: Grant
    Filed: March 19, 2013
    Date of Patent: March 10, 2015
    Assignee: Hypres, Inc.
    Inventors: Deepnarayan Gupta, Amol Inamdar
  • Patent number: 8958766
    Abstract: An electronic appliance comprising an electrical circuit and an operating mode switching unit which can be awakened out of a sleep state into a working state in which the current consumption of the circuit is greater in than in the sleep state. To receive a radio signal, the appliance has a receiver comprising a UHF carrier that is amplitude-modulated by a modulation signal. The receiver comprises a UHF antenna connected to a passive filter stage to an input of a passive rectifier circuit. An output of the rectifier circuit is connected to a detector for the modulation signal. To wake the electrical circuit from the sleep state, the operating mode switching unit has a control connection to the detector. The appliance has a low current draw in the sleep state by matching the output impedance of the rectifier circuit to the input impedance of the detector.
    Type: Grant
    Filed: January 14, 2013
    Date of Patent: February 17, 2015
    Assignee: SmartExergy WMS GmbH
    Inventors: Tolgay Ungan, Gerd Ulrich Gamm, Leonhard Michael Reindl, Thomas Ostertag, Matthias Sippel, Thomas Wendt
  • Patent number: 8934634
    Abstract: A noise level of an output signal is maintained low. An adjacent interference detecting unit compares a signal level of a wide band signal which is a desired station signal of a relatively wide band and a signal level of a narrow band signal which is a desired station signal of a relatively narrow band, and judges that adjacent interference has occurred when the signal level of the narrow band signal is less than or equal to a predetermined level even though the signal level of the wide band signal is greater than or equal to a predetermined level. A variable amplifier (36) attenuates an L?R signal and forms a monophonic signal when the signal level of the narrow band signal is lower than a predetermined level. With this process, when there is adjacent interference, a signal level of the narrow band signal at which the attenuating unit starts attenuating the L?R signal is changed to a relatively high value.
    Type: Grant
    Filed: February 22, 2011
    Date of Patent: January 13, 2015
    Assignee: Semiconductor Components Industries, LLC
    Inventors: Kazunari Kurokawa, Shinya Inaba
  • Patent number: 8917792
    Abstract: A method (600) and apparatus (200) cancel odd-order distortion signals. Desensitization can be determined (610) in a received signal caused by odd-order harmonic distortion occurring from at least one transmit signal. A baseband replica harmonic distortion signal can be generated (620) using the transmit signal. The baseband replica harmonic distortion signal can be converted (630) to a low frequency harmonic distortion signal. The low frequency harmonic distortion signal can be subtracted (640) from the received signal to cancel the odd-order distortion from the received signal to create a corrected signal.
    Type: Grant
    Filed: December 12, 2012
    Date of Patent: December 23, 2014
    Assignee: Motorola Mobility LLC
    Inventors: Gregory R. Black, Dale G. Schwent
  • Publication number: 20140370831
    Abstract: A wide tuning range receiver is provided that includes first and second mixers, and first and second local oscillators. The first mixer can mix an input signal with a signal from the first local oscillator and output a signal having a first intermediate frequency, the second mixer can mix the signal having the first intermediate frequency with a signal from the second local oscillator and output a signal having a second intermediate frequency, and, for each input signal frequency, a relationship between the first and second local oscillators can be fixed.
    Type: Application
    Filed: June 10, 2014
    Publication date: December 18, 2014
    Applicant: PC-TEL, Inc.
    Inventors: Wei Lu, John Kyechong Kim
  • Publication number: 20140364076
    Abstract: The present disclosure relates to a method for reducing second order intermodulation distortion in a harmonic rejection mixer arranged for down-converting a radio frequency signal to an in-phase and a quadrature baseband signal. The method includes adjusting an output current of a first mixer, to reduce the second order intermodulation distortion in the quadrature baseband signal to a first value, and adjusting an output current of a second mixer, to reduce the second order intermodulation distortion in the in-phase baseband signal to a second value.
    Type: Application
    Filed: June 10, 2014
    Publication date: December 11, 2014
    Applicants: RENESAS ELECTRONICS CORPORATION, IMEC
    Inventors: Sungwoo Cha, Jonathan Borremans
  • Patent number: 8897735
    Abstract: Disclosed is a self-correlation receiver of a transceiver in which a transmitter shares an antenna with a receiver. The self-correlation receiver includes: a clamper which receives a received signal, limits the magnitude of the received signal within a predetermined range and outputs a clamping signal; and a mixer which receives the received signal and the clamping signal and outputs a signal having a difference frequency between the received signal and the clamping signal.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: November 25, 2014
    Assignee: Intellectual Discovery Co., Ltd.
    Inventors: Eun-Hee Kim, Jin-Ho Ko
  • Patent number: 8890619
    Abstract: The present disclosure relates to compensation for Passive Intermodulation (PIM) distortion in a receiver. In one embodiment, a main receiver receives a radio frequency receive signal and outputs a main receiver output signal. In order to compensate for PIM distortion, a tunable non-linear circuit generates an Intermodulation Products (IMP) signal that includes a number of IMPs as a function of a signal that is indicative of the radio frequency transmit signal. An auxiliary receiver receives the IMP signal and outputs an auxiliary receiver output signal that includes only a subset of the IMPs that fall within a passband of the main receiver. The auxiliary receiver output signal is adaptively filtered to provide a PIM estimate signal, which is then subtracted from the main receiver output signal to provide a compensated output signal.
    Type: Grant
    Filed: August 2, 2012
    Date of Patent: November 18, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Mark Wyville
  • Patent number: 8891346
    Abstract: A data transmission/reception system includes a data transmission circuit and a data reception circuit. The data transmission circuit includes a pattern detection unit configured to detect a pattern of data to be loaded on inner lines among a plurality of transmission lines and generate an inversion signal, and a transmission unit configured to transmit data to the plurality of transmission lines and the inversion signal to an inversion line, and invert some of the data to be loaded on the inner lines in response to the inversion signal. The data reception circuit is configured to invert the data inverted by the transmission unit among the data transferred to the plurality of transmission lines, in response to the inversion signal.
    Type: Grant
    Filed: July 9, 2010
    Date of Patent: November 18, 2014
    Assignee: SK Hynix Inc.
    Inventor: Guen-Il Lee
  • Patent number: 8880017
    Abstract: A system includes a transceiver configured to receive a composite signal. The composite signal is a composite of a transmit signal and a receive signal. A replica transmitter is configured to generate a replica transmit signal based on the transmit signal. A transmit canceller is configured to recover the receive signal at least in part by resistively summing the composite signal and the replica transmit signal.
    Type: Grant
    Filed: August 5, 2013
    Date of Patent: November 4, 2014
    Assignee: Marvell International Ltd.
    Inventors: Pierte Roo, Sehat Sutardja
  • Patent number: 8874153
    Abstract: Interference to a received signal is reduced in a wireless network, the interference comprising intermodulation products of at least a first signal and a second signal. Delayed interference signals comprising simulated intermodulation products are generated on the basis of the first signal and the second signal using a range of differing delay values and each of the delayed interference signals is correlated with the received signal to produce data representing a correlation for each delayed interference signal. At least one delay value is selected in dependence on a the data representative of the correlations and an interference signal comprising simulated intermodulation products generated from the first signal and the second signal using the at least one delay value is combined with the received signal.
    Type: Grant
    Filed: August 13, 2012
    Date of Patent: October 28, 2014
    Assignee: Aceaxis Limited
    Inventors: David Damian Nicholas Bevan, Simon John Gale, Fiona Maihri Wilson
  • Patent number: 8867650
    Abstract: An apparatus and method for cross clock domain interference cancellation is provided to a communication system which includes a transmitter operated in a first clock domain and a receiver operated in a second clock domain. The apparatus comprises a First-In-First-Out (FIFO) circuit and a cancellation signal generator. The FIFO circuit receives a digital transmission signal of the transmitter in the first clock domain, and outputs the digital transmission signal in the second clock domain according to an accumulated timing difference between the first and second clock domains. The cancellation signal generator generates a cancellation signal for canceling an interference signal received by the receiver according to the digital transmission signal outputted by the FIFO circuit. The interference signal is generated in response to the digital transmission signal.
    Type: Grant
    Filed: February 14, 2012
    Date of Patent: October 21, 2014
    Assignee: Realtek Semiconductor Corp.
    Inventors: Liang-Wei Huang, Shieh-Hsing Kuo, Chi-Shun Weng, Chun-Hung Liu
  • Patent number: 8862087
    Abstract: A method for reciprocal-mixing noise cancellation may include receiving, from a first mixer, a first signal comprising a wanted signal at a first frequency and a modulated signal at a second frequency. The modulated signal may be a product of a reciprocal-mixing of an unwanted signal with a phase noise. One or more portions of the modulated signal may overlap the wanted signal, adding a reciprocal-mixing noise to the wanted signal. A second signal may be generated by mixing, at a second mixer, the first signal with a third signal, which is at a third frequency related to a blocker offset frequency. A gain may be applied to the second signal to generate an amplified second signal that may be subtracted from the first signal to generate a fourth signal. The fourth signal may be filtered to generate the wanted signal at the first frequency without the reciprocal-mixing noise.
    Type: Grant
    Filed: May 17, 2013
    Date of Patent: October 14, 2014
    Assignee: Broadcom Corporation
    Inventors: Mohyee Mikhemar, David Murphy, Hooman Darabi
  • Patent number: 8831548
    Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: September 9, 2014
    Assignee: American Radio LLC
    Inventor: Robert Hotto
  • Publication number: 20140235191
    Abstract: A method for reciprocal-mixing noise cancellation may include receiving, from a first mixer, a first signal comprising a wanted signal at a first frequency and a modulated signal at a second frequency. The modulated signal may be a product of a reciprocal-mixing of an unwanted signal with a phase noise. One or more portions of the modulated signal may overlap the wanted signal, adding a reciprocal-mixing noise to the wanted signal. A second signal may be generated by mixing, at a second mixer, the first signal with a third signal, which is at a third frequency related to a blocker offset frequency. A gain may be applied to the second signal to generate an amplified second signal that may be subtracted from the first signal to generate a fourth signal. The fourth signal may be filtered to generate the wanted signal at the first frequency without the reciprocal-mixing noise.
    Type: Application
    Filed: May 17, 2013
    Publication date: August 21, 2014
    Inventors: Mohyee MIKHEMAR, David Murphy, Hooman Darabi
  • Patent number: 8787861
    Abstract: In some implementations, an apparatus includes an echo canceller that generates an echo interference compensation signal that compensates for an echo interference signal in a communication signal, a crosstalk canceller that generates a crosstalk interference compensation signal that compensates for a crosstalk interference signal in the communication signal, and a combiner that generates a combined interference compensation signal based on the echo interference compensation signal and the crosstalk interference compensation signal.
    Type: Grant
    Filed: September 7, 2012
    Date of Patent: July 22, 2014
    Assignee: Marvell International Ltd.
    Inventors: Xiaopeng Chen, Runsheng He
  • Patent number: 8774747
    Abstract: A radio frequency receiver of the present invention removes out-of-band jamming signals and interference signals without SAW filters. The radio frequency receiver includes: a low noise amplifier amplifying a signal received through an antenna; a second order intermodulation cancellation unit removing second order intermodulation caused by an out-of-band jamming or interference signal included in the signal output from the low noise amplifier; a passive mixer unit converting a frequency of the signal output from the second order intermodulation cancellation unit; and a low pass filter unit removing an out-of-band jamming or interference signal included in the signal output from the passive mixer unit and delivering the signal with the out-of-band jamming or interference signal removed therefrom to a transimpedance amplifier.
    Type: Grant
    Filed: June 5, 2012
    Date of Patent: July 8, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Seok-bong Hyun, Bong Hyuk Park, Yun Ho Choi, Jae Ho Jung
  • Patent number: 8761709
    Abstract: A receiver 650 operates in close proximity to at least one other component 610, 611, 612 causing interferences in signals received by the receiver 650. It is determined (steps 2002; 2003) whether and at which frequency a higher harmonic of and/or an inter-modulation product with signals generated by the other component 610 causes interference in signals received by the receiver 650, based on information about signals generated by the other component 610, 611, 612. At least one characteristic of the receiver 650 is adjusted to diminish an influence by a determined interference.
    Type: Grant
    Filed: March 1, 2006
    Date of Patent: June 24, 2014
    Assignee: Nokia Corporation
    Inventors: Marko Leinonen, Juha Valtanen, Seppo Rousu
  • Patent number: 8718588
    Abstract: A signal processing circuit is used for generating a signal output by processing a signal input, and includes a first mixer unit, a second mixer unit, and a frequency-selective combining block. The first mixer unit is arranged for receiving a first signal and a first oscillation signal, and generating a first mixing output by mixing the first oscillation signal and the first signal. The second mixer unit is arranged for receiving a second signal and a second oscillation signal, and generating a second mixing output by mixing the second oscillation signal and the second signal. Each of the first signal and the second signal is part of the signal input. The first and second oscillation signals have a same frequency but different phases. The frequency-selective combining block is arranged for frequency-selectively combining the first mixing output and the second mixing output to generate the signal output.
    Type: Grant
    Filed: May 30, 2012
    Date of Patent: May 6, 2014
    Assignee: Mediatek Inc.
    Inventor: Chih-Fan Liao
  • Patent number: 8706070
    Abstract: An RF system for reducing intermodulation (IM) products is disclosed. The RF system includes a first nonlinear element and a second nonlinear element, wherein the second nonlinear element generates inherent IM products and the first nonlinear element is adapted to generate compensating IM products. Alternatively, the first nonlinear element generates inherent IM products and the second nonlinear element is adapted to generate compensating IM products. The amplitudes of the compensating IM products are substantially equal to amplitudes of the inherent IM products. The RF system further includes a phase shifter that is adapted to provide a phase shift that results in around 180° of phase shift between the inherent IM products and the compensating IM products. The phase shifter is coupled between the first nonlinear element and the second nonlinear element.
    Type: Grant
    Filed: October 13, 2011
    Date of Patent: April 22, 2014
    Assignee: RF Micro Devices, Inc.
    Inventors: Ali Tombak, Joshua J. Caron, Daniel Charles Kerr
  • Patent number: 8687645
    Abstract: A wireless communications device may include a portable housing and a temperature-compensated clock circuit carried by the portable housing. The device may further include a wireless receiver carried by the portable housing for receiving timing signals, when available, from a wireless network, and a satellite positioning clock circuit carried by the portable housing. A clock correction circuit may be carried by the portable housing for correcting the temperature-compensated clock circuit based upon timing signals from the wireless network when available, and storing historical correction values for corresponding temperatures. The clock correction circuit may also correct the temperature-compensated clock circuit based upon the stored historical correction values when timing signals are unavailable from the wireless network, and correct the satellite positioning clock based upon the temperature-compensated clock circuit.
    Type: Grant
    Filed: July 16, 2012
    Date of Patent: April 1, 2014
    Assignee: BlackBerry Limited
    Inventor: Michael Andrew Goldsmith
  • Patent number: 8682275
    Abstract: A converter in a radio-frequency (RF) apparatus includes a feedback circuitry. The feedback circuitry has a shielded input and a shielded output. The shielded input and the shielded output of the feedback circuitry tend to reduce interference in the converter.
    Type: Grant
    Filed: June 30, 2010
    Date of Patent: March 25, 2014
    Assignee: Silicon Laboratories Inc.
    Inventors: Donald A. Kerth, G. Diwakar Vishakhadatta
  • Patent number: 8681897
    Abstract: Control of a digital communication system having a plurality of communication lines on which signals are transmitted and received is implemented using a variety of methods and systems. According to one embodiment of the present invention, a method is implemented where the signals are affected by interference during transmission and each of the communication lines has at least one transmitter and at least one receiver. A model is created of the interference characteristics due to the signals carried on the communication lines. Interference characteristics for a line are determined based on the model and actual signals carried on other communication lines different from the line for which the characteristics are being determined. Actual interference is compensated for on the communication line using the determined interference characteristics.
    Type: Grant
    Filed: June 19, 2012
    Date of Patent: March 25, 2014
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Georgios Ginis, Wei Yu, Chaohuang Zeng, John M. Cioffi
  • Patent number: 8666325
    Abstract: This disclosure relates to linearization in polar modulators of wireless communication devices, to attain linear amplification and high power efficiency during transmission.
    Type: Grant
    Filed: December 3, 2008
    Date of Patent: March 4, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Nick Shute, Andrei Panioukov, Zdravko Boos
  • Patent number: 8655297
    Abstract: Disclosed are a nonlinear distortion compensating receiver and nonlinear distortion compensation method, wherein nonlinear distortion is reduced with a simple circuit configuration. A correction (opposite characteristics) filter (104) has characteristics opposite that of the frequency characteristics of a direct sampling mixer (102) and corrects signals sampled by the direct sampling mixer (102). In the main path, a LPF (106) extracts a frequency band component of a desired signal from the corrected signal. In the replica path, a BPF (107) extracts the frequency band component of a blocker signal from the corrected signal. A cubing circuit (108) uses the frequency band component of the blocker signal to generate a replica signal for the nonlinear distortion. An adaptive filter (110) performs filter processing on the replica signal while updating the filter coefficients.
    Type: Grant
    Filed: July 5, 2010
    Date of Patent: February 18, 2014
    Assignee: Panasonic Corporation
    Inventors: Satoshi Tsukamoto, Noriaki Saito, Yoshito Shimizu, Tadashi Morita, Katsuaki Abe
  • Patent number: 8644785
    Abstract: This disclosure relates to low noise amplifiers (LNAs) and more particularly to LNAs integrated on integrated circuit (IC) chips along with radio frequency (RF) amplifiers. In one implementation, an impedance translator is coupled to an amplifier, the impedance translator to cause the amplifier to selectively amplify the one or more components of a received signal.
    Type: Grant
    Filed: April 19, 2012
    Date of Patent: February 4, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Rastislav Vazny, Krzysztof Dufrene, Hans Pletzer, Werner Schelmbauer, Harald Pretl
  • Publication number: 20140030995
    Abstract: Receiver design techniques are provided that are capable of producing relatively efficient, linear radio frequency (RF) receivers. During a design process, components of an analog receiver chain and digital nonlinearity compensation techniques are considered together to achieve reduced power consumption in the receiver.
    Type: Application
    Filed: July 25, 2013
    Publication date: January 30, 2014
    Applicant: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
    Inventors: Helen Kim, Merlin Green, Andrew Bolstad, Daniel D. Santiago, Michael N. Ericson, Karen Gettings, Benjamin A. Miller
  • Patent number: 8634794
    Abstract: A method, apparatus, and radio receiver system for canceling multi-user interference in a single-carrier radio communication system. A front-end receiver such as a RAKE receiver receives a radio signal formatted in a sequence of frames, and outputs a plurality of user signals. A processing selector selects on a frame-by-frame basis, either a first signal processing chain that serially decodes and removes the interference contributions of the user signals, or a second signal processing chain that simultaneously decodes and removes the interference contributions of the user signals in parallel. The processing selector may select the first signal processing chain when the number of user signals is greater than or equal to a threshold value, and may select the second signal processing chain when the number of user signals is less than the threshold value.
    Type: Grant
    Filed: August 11, 2010
    Date of Patent: January 21, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Sairamesh Nammi, Narendra Tilwani
  • Patent number: 8634793
    Abstract: A radio frequency receiver on an integrated circuit (RFIC) includes an oscillator circuit, which generates a radio frequency (RF) oscillatory signal having a predetermined frequency that is outside of an intermediate frequency passband of the RFIC. An amplitude modulator modulates the RF oscillatory signal to produce an amplitude modulated signal which is applied to a mixer that downconverts the amplitude modulated signal. A calibration circuit receives the downconverted signal, including second order modulation (IM2) products, and, responsive to the IM2 products, generates a bias signal that is applied to the mixer to reduce the IM2 products.
    Type: Grant
    Filed: May 10, 2010
    Date of Patent: January 21, 2014
    Assignee: CSR Technology Inc.
    Inventors: Joakim Landmark, Noshir Dubash, Daniel Babitch