Automatic Frequency Control Patents (Class 375/344)
  • Patent number: 11502883
    Abstract: A mixer in a receiver converts a sounding sequence of alternating ones and zeros to an intermediate frequency signal. A digital mixer converts the intermediate frequency signal to a baseband signal that contains a positive tone and a negative tone. A frequency offset correction circuit generates frequency offset corrections based on frequency offset estimates of the frequency offset between a transmitter of the sounding sequence and the receiver. A frequency adjustment circuit adjusts a frequency of the mixer or the digital mixer to thereby center the positive tone and the negative tone around DC. DFT circuits perform single bin DFTs respectively centered on the positive and negative tones. Phases of the positive and negative tones are calculated based on outputs of the DFT circuits and the phases are used to determine fractional time value associated with a distance measurement between the transmitter and receiver.
    Type: Grant
    Filed: December 1, 2020
    Date of Patent: November 15, 2022
    Assignee: Silicon Laboratories Inc.
    Inventors: Wentao Li, Michael A. Wu, Yan Zhou
  • Patent number: 11463071
    Abstract: A system and method for providing asymmetrical filtering to improve performance in the presence of wideband interference is herein disclosed. According to one embodiment, a method for a global navigation satellite system (GNSS) receiver includes detecting wideband interference in a received target GNSS signal, and applying an asymmetric filter to the received target GNSS signal to mitigate the detected wideband interference.
    Type: Grant
    Filed: July 23, 2018
    Date of Patent: October 4, 2022
    Inventor: Gary Lennen
  • Patent number: 11457417
    Abstract: A method and related apparatus for transferring data between a mobile communication unit and a plurality of access points, wherein each of said plurality of access points and said mobile communication unit is provided with a transceiver, said mobile communication unit being arranged to travel a predetermined route, the method comprising: adjusting transmission power of at least the transceiver of the mobile communication unit substantially to a maximum level; and attenuating transmission signal of each transceiver such that signal level of a received signal in a transmission between the mobile communication unit and each of the access points is more optimal, wherein the level of attenuation is set constant at least in the mobile communication unit.
    Type: Grant
    Filed: June 11, 2015
    Date of Patent: September 27, 2022
    Assignee: Teleste Oyj
    Inventors: Jani Vare, Kari Virtanen
  • Patent number: 11336406
    Abstract: One general aspect of the present disclosure includes a device configured to operate in a wireless system. The device including: a transceiver configured with a plurality of E-UTRA operating bands; and a processor operably connectable to the transceiver. The processer may be configured to: control the transceiver to transmit an uplink signal via at least two bands among the plurality of E-UTRA operating bands; and control the transceiver to receive a downlink signal via three bands among the plurality of E-UTRA operating bands, wherein pre-configured MSD value is applied to a reference sensitivity for receiving the downlink signal based on the E-UTRA operating band 2.
    Type: Grant
    Filed: March 25, 2020
    Date of Patent: May 17, 2022
    Assignee: LG Electronics Inc.
    Inventors: Jongkeun Park, Yoonoh Yang, Sangwook Lee, Suhwan Lim, Manyoung Jung, Jinyup Hwang
  • Patent number: 11303487
    Abstract: [Problem] Conventionally, in a wireless communication system that performs single-carrier communication with formation of symbol blocks, it has been difficult to select the optimal GI length and modulation and coding method that achieve the maximum throughput. [Means of Solution] A transmission device and a reception device are included.
    Type: Grant
    Filed: February 25, 2019
    Date of Patent: April 12, 2022
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Keita Kuriyama, Hayato Fukuzono
  • Patent number: 11277117
    Abstract: A filter includes multiple filter circuits. The filter circuits are coupled in series between an input terminal and an output terminal, to generate an output signal according to an input signal. One of the filter circuits operates as an active filter circuit or a passive filter circuit according to amplitude of the input signal.
    Type: Grant
    Filed: August 4, 2020
    Date of Patent: March 15, 2022
    Assignee: REALTEK SEMICONDUCTOR CORPORATION
    Inventors: Wei-Chen Lin, Hsuan-Yi Su, Chih-Lung Chen
  • Patent number: 11240048
    Abstract: Embodiments described herein provide a method for waking a first node in a low power mode. A network comprises at least the first node and a second node in an awake mode where the first and second nodes have respective transceivers coupled via substantially fixed communication pathways. The transceiver of the second node obtains a training signal designed to be transmitted at a pre-defined symbol rate and transmits the training signal at a symbol rate lower than the pre-defined symbol rate to the physical layer of the first node for a predetermined duration of time. The second node, in response to receiving the training signal transitions from the low power mode to an awake state.
    Type: Grant
    Filed: March 6, 2020
    Date of Patent: February 1, 2022
    Assignee: Marvell Asia Pte, Ltd.
    Inventors: Shaoan Dai, Wyant Chan, Xing Wu, Liang Zhu, Hon Wai Fung
  • Patent number: 11165622
    Abstract: Systems and methods are described, and one method includes acquiring a frequency offset for a demodulator receiving one symbol rate in combination with acquiring another frequency offset for another demodulator, based on sweeping the other frequency offset until detecting a qualifying symbol pattern or acquiring the frequency offset for the demodulator receiving one symbol rate, whichever occurs first. Associated with acquiring the other frequency offset based on acquiring the frequency offset for the demodulator receiving one symbol rate, setting the other frequency offset includes adjusting the frequency offset for the demodulator receiving one symbol rate.
    Type: Grant
    Filed: October 18, 2019
    Date of Patent: November 2, 2021
    Assignee: Hughes Network Systems, LLC.
    Inventors: Nimesh Prakash Ambeskar, Daniel Christopher Hantz, Joyal Jose
  • Patent number: 11129098
    Abstract: A transmit/receive signal processor for Wireless Local Area Network (WLAN) and Bluetooth has selectable signal processing elements for mixers, Intermediate Frequency (IF) filters, transmit power amplifiers, and clock sources which are suitable for either Bluetooth or WLAN signal processing. The operating mode of the signal processor is selected to be one of Wireless High Performance, Wireless Low Power, Bluetooth High Performance or Bluetooth Low power, and the signal processing modules are selected to provide performance or power requirements using selected modules.
    Type: Grant
    Filed: October 11, 2019
    Date of Patent: September 21, 2021
    Assignee: Silicon Laboratories Inc.
    Inventors: Venkat Mattela, Partha Sarathy Murali, Ajay Mantha
  • Patent number: 11121721
    Abstract: In an embodiment, a method includes: receiving an audio frame; decomposing the received audio frame into M sub-band pulse-code modulation (PCM) audio frames, where M is a positive integer number; predicting a PCM sample of one sub-band PCM audio frame of the M sub-band PCM audio frames; comparing the predicted PCM sample with a corresponding received PCM sample to generate a prediction error sample; comparing an instantaneous absolute value of the prediction error sample with a threshold; and replacing the corresponding received PCM sample with a value based on the predicted PCM sample when the instantaneous absolute value of the prediction error sample is greater than the threshold.
    Type: Grant
    Filed: July 23, 2020
    Date of Patent: September 14, 2021
    Assignee: STMicroelectronics S.r.l.
    Inventors: Marta Gómez Correa, Fabio Dell'Orto, Muhammad Umair Saeed
  • Patent number: 11095491
    Abstract: Methods and apparatus for frequency offset estimation are disclosed. In an exemplary embodiment, a method includes determining a demodulation reference signal (DMRS) frequency offset estimate from DMRS symbols in a received signal, and determining a cyclic prefix (CP) frequency offset estimate from cyclic prefix values in the received signal. The method also includes combining the DMRS and CP frequency offset estimates to determine a final frequency offset estimate. In an exemplary embodiment, an apparatus includes a DMRS frequency offset estimator that determines a DMRS frequency offset estimate based on DMRS symbols received in an uplink transmission, and a cyclic prefix (CP) frequency offset estimator that determines a CP frequency offset estimate based on cyclic prefix values in the uplink transmission. The apparatus also includes an offset combiner that combines the DMRS frequency offset estimate with the CP frequency offset estimate to generate a final frequency offset estimate.
    Type: Grant
    Filed: January 15, 2020
    Date of Patent: August 17, 2021
    Assignee: Cavium, LLC.
    Inventors: Hyun Soo Cheon, Hong Jik Kim, Tejas Maheshbhai Bhatt
  • Patent number: 10938345
    Abstract: The present application relates to a differential Colpitts voltage-controlled oscillator (VCO) circuit, which comprises a pair of transistors with control terminals biased by a common biasing voltage and a pair of couplers arranged to cross-couple corrector/drain of the transistors and the base/gate of the differential transistors. The pair of couplers have a coupling factor kc, which used to enhance the transconductance of the transistor pair, therefore can be used for power consumption reduction and phase noise minimalization.
    Type: Grant
    Filed: June 25, 2019
    Date of Patent: March 2, 2021
    Assignee: NXP USA, INC.
    Inventor: Yi Yin
  • Patent number: 10900805
    Abstract: A demodulator for demodulating the in-phase component of an input signal which is in-phase and quadrature modulated. The demodulator includes a register storing a phase calibration value and a temperature sensor that performs a plurality of temperature sensings. A compensating stage generates for each temperature sensed a corresponding first sample on the basis of the difference between the sensed temperature and a calibration temperature and a compensation function indicative of a relationship existing between the phase of the input signal and the temperature. A combination stage generates a plurality of second samples, each second sample being a function of the phase calibration value and a corresponding first sample. A generating stage generates a demodulating signal having a phase which depends on the second samples and a demodulating stage demodulates the input signal by means of the demodulating signal.
    Type: Grant
    Filed: March 13, 2018
    Date of Patent: January 26, 2021
    Assignee: STMicroelectronics S.r.l.
    Inventors: Matteo Quartiroli, Alessandro Mecchia, Paolo Pesenti, Stefano Facchinetti, Andrea Donadel
  • Patent number: 10903867
    Abstract: A receiver includes one or more mixers configured to sample an input analog signal at a plurality of discrete points in time to obtain a discrete-time sampled signal based on a local oscillating signal provided by a local oscillator; and a sample reordering circuit coupled to the one or more mixers and configured to reorder a sequence of samples received from the one or more mixers.
    Type: Grant
    Filed: August 30, 2019
    Date of Patent: January 26, 2021
    Assignee: U-BLOX AG
    Inventors: Norman Beamish, Mici McCullagh
  • Patent number: 10855329
    Abstract: A hopping spread-spectrum wireless network for IoT applications with mobile device that have unsynchronized local frequency references. The transmitters use hopping sequences defined in term of the relative differences of frequencies, in such a manner that a receiver can determine the hopping sequence of a transmission despite the presence of a large frequency error.
    Type: Grant
    Filed: June 11, 2019
    Date of Patent: December 1, 2020
    Assignee: Semtech Corporation
    Inventors: Olivier Bernard André Seller, Nicolas Sornin
  • Patent number: 10779140
    Abstract: A vehicle communication apparatus includes a plurality of remote units (RUs) configured to transmit signals to a mobile communication network and to receive signals from the mobile communication network, and a central unit (CU) configured to provide data based on the signals received through the plurality of remote units to one or more devices located in a vehicle. The plurality of remote units includes an array antenna attached to a body of the vehicle.
    Type: Grant
    Filed: September 12, 2019
    Date of Patent: September 15, 2020
    Assignee: LG Electronics Inc.
    Inventors: Heejin Kim, Jiwon Kang, Sunam Kim, Hanbyul Seo, Sangwook Lee
  • Patent number: 10778347
    Abstract: A vehicle communication apparatus includes a plurality of remote units (RUs) configured to transmit signals to a mobile communication network and to receive signals from the mobile communication network, and a central unit (CU) configured to provide data based on the signals received through the plurality of remote units to one or more devices located in a vehicle. The plurality of remote units includes an array antenna attached to a body of the vehicle.
    Type: Grant
    Filed: July 25, 2017
    Date of Patent: September 15, 2020
    Assignee: LG Electronics Inc.
    Inventors: Heejin Kim, Jiwon Kang, Sunam Kim, Hanbyul Seo, Sangwook Lee
  • Patent number: 10739579
    Abstract: A method includes determining a set of pattern position errors between (i) a set of expected pattern positions of a calibration pattern on a laser target situated in a laser processing field of a laser system and produced based on a set of initial scan optic actuation corrections associated with a scan optic of the laser system and (ii) a set of measured pattern positions of the calibration pattern, determining a set of scan optic actuation rates based on the set of initial scan optic actuation corrections, and updating the set of initial scan optic actuation corrections based on the set of scan optic actuation rates and the set of pattern position errors so as to form a set of updated scan optic actuation corrections that is associated with a reduction of at least a portion of the set of pattern position errors.
    Type: Grant
    Filed: April 18, 2019
    Date of Patent: August 11, 2020
    Assignee: nLIGHT, Inc.
    Inventors: Jay Small, Ken Gross, Vito P. Errico
  • Patent number: 10735168
    Abstract: A method for wireless interrogation of data from a passive element. A first high frequency signal sent to the element excites the element to transmit a response signal which is received and mixed with a reference signal in a mixer, generating a data signal. The data signal is evaluated to extract data. A second high frequency signal generated from the same frequency reference as the first frequency signal is used as a reference signal. A control signal is generated by mixing the reference and first frequency signals. The data signal is bandpass-filtered in analog form and is converted, with the control signal, to a digital signal and digital control signal which are then each bandpass-filtered in digital form. The digital data and digital control signals are correlated to form a result signal so that a digital coherence is achieved. Raw data representing the data are obtained from the result signal.
    Type: Grant
    Filed: November 14, 2016
    Date of Patent: August 4, 2020
    Assignee: Pro-Micron GmbH & Co. KG
    Inventors: Malek Chaabane, André Wiedbrauk
  • Patent number: 10630526
    Abstract: An estimation apparatus for IQ imbalance of an optical transmitter, a compensation apparatus for IQ imbalance of an optical transmitter and electronic equipment; wherein, estimation and compensation of IQ imbalance of an optical transmitter are performed by directly using an estimation model based on a transform matrix of received signals and transmitted signals, therefore, a phase offset shift may be estimated accurately, and precision of estimation of drifts of various angles is ensured, furthermore, accurate recovery of the constellation diagram of received signals is achieved.
    Type: Grant
    Filed: October 18, 2018
    Date of Patent: April 21, 2020
    Assignee: FUJITSU LIMITED
    Inventors: Yangyang Fan, Zhenning Tao
  • Patent number: 10516498
    Abstract: A WAP for wireless communications on a selected orthogonal frequency division multiplexed (OFDM) communication channel of a wireless local area network (WLAN). The transceiver includes: antennas, transmit and receive chain components, a stream separation control circuit, and an Inter Carrier Interference (ICI) removal circuit. The receive chain components include: an equalizer component converting a received uplink communication packet from one or more of the associated stations at an input into discrete communication streams at an output thereof. The stream separation control circuit couples to the equalizer component to control the separation of the communication streams at the output of the equalizer component into groups, with each group comprising all of the communication streams transmitted by a corresponding one of the one or more associated stations. The ICI removal circuit couples to the stream separation control circuit to discretely remove ICI from each group of streams.
    Type: Grant
    Filed: May 31, 2017
    Date of Patent: December 24, 2019
    Assignee: QUANTENNA COMMUNICATIONS, INC.
    Inventors: Kirill Yurkov, Mikhail Lyakh, Hossein Dehghan
  • Patent number: 10476535
    Abstract: A high-frequency front end circuit includes a frequency fixed filter and frequency variable LC filters, and these are connected in series in a signal transmission path. The frequency fixed filter transmits high-frequency signals in a frequency band of a communication band and attenuates high-frequency signals outside the frequency band of the communication band. One of the frequency variable LC filters is an LC filter and attenuates unnecessary wave frequencies in the frequency band of the communication band. Another one of the frequency variable filters is a resonator filter that passes high-frequency signals in a frequency band of a selected channel and attenuates high-frequency signals in frequency bands of adjacent communication channels of the selected channel.
    Type: Grant
    Filed: March 8, 2018
    Date of Patent: November 12, 2019
    Assignee: MURATA MANUFACTURING CO., LTD.
    Inventors: Hidenori Obiya, Atsushi Horita, Hirotsugu Mori
  • Patent number: 10469111
    Abstract: A wireless communication device detects when the wireless communication device is in a high speed environment, e.g., on a high speed train, and detects whether the behavior of the automatic frequency control (AFC) shall be changed since the AFC behavior is not stable. Receiver algorithms, i.e., the AFC, are changed such that an optimization for the high speed environment is obtained, without any risk of degrading the performance in all other fading environments.
    Type: Grant
    Filed: August 12, 2016
    Date of Patent: November 5, 2019
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventor: Torgny Palenius
  • Patent number: 10320512
    Abstract: An interference cancelation receiver can cancel channel state information reference signal interference using a single fast fourier transform (FFT), thereby reducing the complexity of the receiver. The transmitter can multiplex a channel state information reference signal (CSI-RS) with a physical downlink shared channel (PDSCH) of another numerology, thereby improving a resource utilization. Thus, significant gains in link and system throughputs can be achieved via the use of the interference cancelation receiver.
    Type: Grant
    Filed: January 8, 2017
    Date of Patent: June 11, 2019
    Assignee: AT&T INTELLECTUAL PROPERTY I, L.P.
    Inventors: SaiRamesh Nammi, Xiaoyi Wang, Arunabha Ghosh
  • Patent number: 10299679
    Abstract: The present disclosure provides a method and a system for wirelessly and passively measuring temperature and devices forming the system. The method includes: receiving an energy feedback radio frequency (RF) signal by a temperature measuring end; converting the energy feedback RF signal into electric energy and storing the electric energy; and starting the temperature measuring end after obtaining the electric energy, and transmitting a RF signal under the current temperature to a terminal, and calculating the current temperature through the terminal. The method, the system and the devices forming the system provided in the present disclosure are capable of activating the crystal oscillator or the ceramic oscillator wirelessly and passively, therefore, the method, the system and the devices can be used to wirelessly and passively measure temperature, which is convenient.
    Type: Grant
    Filed: June 27, 2016
    Date of Patent: May 28, 2019
    Assignee: Shenzhen Zhiying Technologies Co., Ltd.
    Inventor: Song Yang
  • Patent number: 10292122
    Abstract: The present disclosure provides a method implemented in an access point, AP, for maintaining synchronization among APs in a radio access network as well as the AP. The method comprises at least one of a transmission step and a reception step. At the transmission step, a first inter-AP synchronization signal is transmitted to a first neighboring AP, which synchronizes to the AP, at a transmission resource indicated by a first synchronization signal transmission/reception pattern associated with the AP, when the first neighboring AP receives the first inter-AP synchronization signal at a reception resource indicated by a second synchronization signal transmission/reception pattern associated with the first neighboring AP, wherein the reception resource indicated by the second synchronization signal transmission/reception pattern overlaps with the transmission resource indicated by the first synchronization signal transmission/reception pattern.
    Type: Grant
    Filed: October 11, 2014
    Date of Patent: May 14, 2019
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Jinhua Liu, Gen Li, Zhan Zhang
  • Patent number: 10284410
    Abstract: Aspects of the present disclosure are directed to processing signals received from different sources, such as may be relevant to receiving signals having respective time-offsets based upon a distance via which the respective signals travel, and/or due to an oscillator clock mismatch. As may be implemented in accordance with one or more embodiments, respective fast Fourier transform (FFT) series are generated for symbols in respective ones of communications received in parallel. For each message that the receiver is trying to decode, channel estimation is performed on the respective FFT series, and one of the FFT series is selected based upon metrics indicative of interference in the respective FFT series, for that particular message. A decoding timing window is set based on the selected FFT series, and the selected FFT series is decoded.
    Type: Grant
    Filed: August 28, 2018
    Date of Patent: May 7, 2019
    Assignee: NXP B.V.
    Inventor: Vincent Pierre Martinez
  • Patent number: 10243541
    Abstract: A method includes receiving a signal from a remote transmitter via an electrically-tunable antenna having a tunable element. An adjustment, to be applied to a response of the electrically-tunable antenna, is calculating by analyzing the received signal. The response of the electrically-tunable antenna is adapted by controlling the tunable element responsively to the estimated adjustment.
    Type: Grant
    Filed: November 8, 2017
    Date of Patent: March 26, 2019
    Assignee: ALTAIR SEMICONDUCTOR LTD.
    Inventors: Dima Feldman, Yigal Bitran, Ariel Yagil
  • Patent number: 10237839
    Abstract: Aspects of the present disclosure provide techniques for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations.
    Type: Grant
    Filed: June 14, 2016
    Date of Patent: March 19, 2019
    Assignee: QUALCOMM Incorporated
    Inventors: Lin Yang, Bin Tian, Tao Tian
  • Patent number: 10211958
    Abstract: A method for transmitting information, a station, and an access point in a MU-MIMO system includes: determining, by a first station, multiple to-be-sent first long training sequences, where the multiple first long training sequences include at least one pilot for phase tracking; and sending, by the first station, the multiple first long training sequences to an access point on multiple symbols, where a second station sends multiple second long training sequences to the access point on the multiple symbols, the multiple second long training sequences include at least one pilot for phase tracking, and a first pilot for phase tracking and a second pilot for phase tracking occupy different time-frequency resources, where the at least one pilot for phase tracking included in the multiple first long training sequences includes the first pilot for phase tracking.
    Type: Grant
    Filed: January 27, 2017
    Date of Patent: February 19, 2019
    Assignee: HUAWEI TECHNOLOGIES CO., LTD.
    Inventors: Weishan Lu, Doron Ezri, Le Liu
  • Patent number: 10129070
    Abstract: Methods and systems for correcting carrier frequency offsets (CFOs) in a wireless transceiver are disclosed. The method includes receiving a first predetermined number of data packets and analyzing the first predetermined number of data packets to determine one or more wireless link quality metrics. The method includes adjusting a local oscillator in accordance with a first local oscillator adjustment strategy. The method includes receiving a second predetermined number of data packets and analyzing the second predetermined number of data packets to determine the one or more wireless link quality metrics. The method includes repeating the first local oscillator adjustment strategy if the wireless link quality metrics improve. The method includes changing to a second local oscillator adjustment strategy if the wireless link quality metrics worsen and adjusting the local oscillator in accordance with the second local oscillator adjustment strategy.
    Type: Grant
    Filed: December 28, 2016
    Date of Patent: November 13, 2018
    Assignee: Phazr, Inc.
    Inventors: Robert Clark Daniels, Khurram Muhammad, Farooq Khan
  • Patent number: 10122422
    Abstract: Diversity receiver front end system with amplifier phase compensation. A receiving system can include a first amplifier disposed along a first path, corresponding to a first frequency band, between an input of the receiving system and an output of the receiving system. The receiving system can include a second amplifier disposed along a second path, corresponding to a second frequency band, between the input of the receiving system and the output of the receiving system. The receiving system can include a first phase-shift component disposed along the first path and configured to phase-shift the second frequency band of a signal passing through the first phase-shift component based on a phase-shift caused by the first amplifier at the second frequency band.
    Type: Grant
    Filed: May 30, 2017
    Date of Patent: November 6, 2018
    Assignee: SKYWORKS SOLUTIONS, INC.
    Inventor: Stephane Richard Marie Wloczysiak
  • Patent number: 10103701
    Abstract: A channel selector for a frequency modulation radio frequency receiver, including a band-pass filter, of which the frequency band is centered on the central frequency of the channel to be selected, and has a width that is automatically variable between a minimum value and a maximum value, the minimum value being determined dynamically proportional to a weighted sum of the field level and the modulation level of the channel, according to a formula MinBW=k1×C+k2×M, in which MinBW is the minimum value, C the field level, k1 the weight associated with the field level, M the modulation level, and k2 the weight associated with the modulation level. The weight associated with the field level is less than the weight associated with the modulation level, preferably in a ratio of 1:3.
    Type: Grant
    Filed: February 22, 2016
    Date of Patent: October 16, 2018
    Assignees: CONTINENTAL AUTOMOTIVE FRANCE, CONTINENTAL AUTOMOTIVE GMBH
    Inventor: Laurent Thery
  • Patent number: 9985805
    Abstract: An adaptive recursive filter is disclosed. The filter includes a filtering device to iteratively apply a recursive filter to signal frames corresponding to portions of a sampled broadband signal. Each iteration of the recursive filter may include generating an autocorrelation signal of an input signal frame, calculating a ratio of a magnitudes of a pair of successive points of the autocorrelation signal, comparing the ratio to a selected signal detection threshold such that a value of the ratio greater than a threshold indicates at least one signal of interest, calculating an energy-weighted average frequency of the input signal frame as a frequency of interest, comparing a spectral energy of the input signal frame at the frequency of interest to spectral energies of surrounding frequencies to identify a frequency of a narrowband interference signal, and filtering the input signal frame at the identified frequency to remove the identified narrowband interference signal.
    Type: Grant
    Filed: July 12, 2017
    Date of Patent: May 29, 2018
    Assignee: Rockwell Collins, Inc.
    Inventors: Mark P. Swenholt, Jeffrey L. Box
  • Patent number: 9935720
    Abstract: A system includes a laser configured to generate a tunable optical frequency. The system also includes an optical transmitter to map baseband data to symbols represented in a digital modulation constellation, add a frequency offset to the digital modulation constellation to cause the digital modulation constellation to rotate at a rate equal to the added frequency offset, modulate the optical frequency with the rotating digital modulation constellation, and transmit the resulting modulated optical frequency. The system also includes an optical receiver to receive the transmitted modulated optical frequency and, using the tunable optical frequency, detect the rotating digital modulation constellation conveyed by the received modulated optical frequency.
    Type: Grant
    Filed: July 7, 2017
    Date of Patent: April 3, 2018
    Assignee: Cisco Technology, Inc.
    Inventors: Christopher Fludger, Thomas Duthel, Joerg Leykauf, Karsten Michaelsen
  • Patent number: 9888475
    Abstract: A wired network may be used to carry signals for a wireless network, in a frequency-shifted manner, to extend the range of the wireless network. A wired network may detect signal interference emanating from a wireless service provider, and received through a leak in the wired network's infrastructure. Devices may be installed or leveraged in the vicinity of the interference to extend the wireless service to geographic areas that may have poor reception. The devices may amplify wireless downstream signals and transmit them wirelessly, and may receive upstream wireless communications and transmit them upstream in the wired network's protocol.
    Type: Grant
    Filed: June 30, 2016
    Date of Patent: February 6, 2018
    Assignee: Comcast Cable Communications, LLC
    Inventors: Lawrence D. Wolcott, Kevin Johns
  • Patent number: 9866416
    Abstract: Embodiments of the present invention relate to methods and systems for simultaneous communication with multiple wireless communication devices. In some embodiments, a method for simultaneous communication with multiple wireless communication devices includes receiving, using a plurality of antennas at a first wireless station, a plurality of packets, comprised of orthogonal frequency division multiplexing (OFDM) wireless signals, transmitted simultaneously from a plurality of other wireless stations wherein each of the simultaneously transmitted packets includes a plurality of frequency tones, frequency domain transform the received packets, grouping frequency domain transform outputs for each subcarrier, determining a difference between subcarrier groups formed over different sample sets, and determining a set of weights for each subcarrier, wherein the weights are selected such that the first wireless station can at least one of detect or demodulate the received plurality of packets.
    Type: Grant
    Filed: September 23, 2016
    Date of Patent: January 9, 2018
    Assignee: Cisco Technology, Inc.
    Inventor: Daniel Joseph Lyons
  • Patent number: 9843307
    Abstract: A method includes receiving a signal from a remote transmitter via an electrically-tunable antenna having a tunable element. An adjustment, to be applied to a response of the electrically-tunable antenna, is calculating by analyzing the received signal. The response of the electrically-tunable antenna is adapted by controlling the tunable element responsively to the estimated adjustment.
    Type: Grant
    Filed: October 2, 2015
    Date of Patent: December 12, 2017
    Assignee: ALTAIR SEMICONDUCTOR LTD.
    Inventors: Dima Feldman, Yigal Bitran, Ariel Yagil
  • Patent number: 9755849
    Abstract: A digital broadcasting system and a data processing method are disclosed. A receiving system of the digital broadcasting system includes a receiving unit, an SI handler, and a decoding unit. The receiving unit receives broadcast signals including mobile service data and main service data. The mobile service data configure a data group, and the data group includes a signaling information region in some of a plurality of data regions. The signaling information region may include TPC signaling data and FIC signaling data. The SI handler acquires channel configuration information of the mobile service data from the broadcast signal using pre-decided IP access information, and extracts encoding format information for each IP stream component within a corresponding virtual channel service RTP-packetized and received from the acquired channel configuration information. The decoding unit decodes the mobile service data of the corresponding IP stream component based upon the extracted encoding format information.
    Type: Grant
    Filed: May 10, 2016
    Date of Patent: September 5, 2017
    Assignee: LG ELECTRONICS INC.
    Inventors: Jae Hyung Song, In Hwan Choi, Jong Yeul Suh, Jin Pil Kim, Chul Soo Lee
  • Patent number: 9735888
    Abstract: In an optical receiver, an optical local oscillator (LO) frequency is generated. A modulated optical frequency is received at the optical receiver. An LO-signal frequency offset between the received modulated optical frequency and the optical LO frequency is determined. A determination is made as to whether the LO-signal frequency offset is in one of multiple predefined non-overlapping target windows that cover respective non-zero LO-signal frequency offsets. If it is determined that the LO-signal frequency offset is not in one of the target windows, the optical LO frequency is tuned to drive the LO-signal frequency offset toward one of the target windows to ensure the LO-signal frequency offset is non-zero.
    Type: Grant
    Filed: October 23, 2015
    Date of Patent: August 15, 2017
    Assignee: Cisco Technology, Inc.
    Inventors: Christopher Fludger, Thomas Duthel, Joerg Leykauf, Karsten Michaelsen
  • Patent number: 9735997
    Abstract: The present invention concerns a method for correcting a frequency shift on symbols received by a receiver, each symbol being composed of N samples and of a cyclic prefix of a predetermined number ? samples, the ? samples being a copy of ? samples of the N samples. The receiver: —calculates for each symbol, a correlation between at most the ? samples of the cyclic prefix and the at most ? samples among the last samples, —averages the correlations over a number of symbols and determines one smooth frequency shift estimation for each averaged correlation, —calculates an exponential from the smooth frequency shift estimation, delays the received symbols by a delay, —multiplies the exponential by the delayed received symbols.
    Type: Grant
    Filed: August 26, 2013
    Date of Patent: August 15, 2017
    Assignee: MITSUBISHI ELECTRIC CORPORATION
    Inventor: Damien Castelain
  • Patent number: 9712316
    Abstract: In a phase error corrector, a signal extractor extracts received reference signals from received signals, and an error vector calculator calculates the error vectors of phase errors by comparing the extracted received reference signals with a known reference signal that is to be transmitted. A representative vector calculator divides, according to frequency, the error vectors into two or more groups and calculates representative vectors for the respective groups. A correction value calculator calculates, on the basis of the representative vectors, phase correction values for the respective frequencies. A phase corrector uses the calculated phase correction values to correct the phase errors for the respective frequencies.
    Type: Grant
    Filed: February 20, 2014
    Date of Patent: July 18, 2017
    Assignee: Panasonic Corporation
    Inventors: Yoshinori Shirakawa, Koichiro Tanaka, Takenori Sakamoto
  • Patent number: 9712263
    Abstract: An example communications device may include a slicer that may generate a digital output signal by thresholding a received signal according to variably set timing and voltage parameters. Testing circuitry may determine expected bit error ratios for multiple time-voltage slices by performing test operations corresponding respectively to the multiple time-voltage slices. Each of the test operations may include setting the timing and voltage parameters of the slicer based on the corresponding time-voltage slice, periodically measuring a bit error ratio based on the digital output signal and determining a confidence level for the measured bit error ratio, and in response to the determined confidence level equaling or exceeding a specified value, designating a current value of the measured bit-error ratio as the expected bit error ratio for the corresponding time-voltage slice and ending the test operation.
    Type: Grant
    Filed: September 1, 2016
    Date of Patent: July 18, 2017
    Assignee: Hewlett Packard Enterprise Development LP
    Inventors: Karl J. Bois, Benjamin Toby, David P. Kopp
  • Patent number: 9705474
    Abstract: According to one embodiment, in a complex band pass filter, a second input signal to be supplied to a second active filter circuit has a substantially 90 degree phase difference from a first input signal to be supplied to a first active filter circuit. The first feedback circuit includes a first element having a first impedance and feeds back an output signal of the first active filter circuit to input side of the second active filter circuit. The second feedback circuit includes a second element having a second impedance different from the first impedance and feeds back an output signal of the second active filter circuit to input side of the first active filter circuit. The output circuit outputs an output signal according to a signal from the first active filter circuit and to a signal from the second active filter circuit.
    Type: Grant
    Filed: March 25, 2016
    Date of Patent: July 11, 2017
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Naotaka Koide
  • Patent number: 9680667
    Abstract: A circuit includes a calculation circuit configured to calculate a noise power of a predetermined-training-sequence pattern repeatedly included in a first signal input into an adaptive equalizer, based on a second signal obtained by compensating the first signal by a compensation circuit, a channel-estimation value based on the second signal, and the predetermined-training-sequence pattern; and an average circuit configured to obtain an average value of estimation values of frequency offsets based on the predetermined-training-sequence pattern having the noise power equal to or smaller than a predetermined power, among estimation values of frequency offsets based on the predetermined-training-sequence pattern, wherein the compensation circuit is configured to compensate a frequency offset of the predetermined-training sequence pattern based on the average value and thereby obtain the second signal, and the adaptive equalizer is configured to perform adaptive-equalization processing of the first signal with a
    Type: Grant
    Filed: July 6, 2016
    Date of Patent: June 13, 2017
    Assignee: FUJITSU LIMITED
    Inventors: Daisuke Sasaki, Kazuhiko Hatae, Tomoki Katou, Nobukazu Koizumi, Masato Oota, Yasuo Ohtomo, Manabu Yamazaki, Masashi Sato
  • Patent number: 9660679
    Abstract: A wireless receiver automatic gain control system includes: a coarse amplification subsystem that receives and amplifies a carrier-modulated signal; a demodulator that generates a baseband signal from the amplified carrier-modulated signal; a fine amplification subsystem that amplifies the baseband signal; and a controller connected to the amplification subsystems. The controller: obtains a unified gain value for the amplification subsystems; based on the unified gain value, selects (i) one of a plurality of coarse gain values defining a set of coarse gain steps each spanning a plurality of unified gain steps, and (ii) one of a plurality of fine gain values defining a set of fine gain steps each spanning a single unified gain step; and sets (i) the gain of the coarse amplification subsystem to the selected coarse gain value, and (ii) the gain of the fine amplification subsystem to the selected fine gain value.
    Type: Grant
    Filed: July 26, 2016
    Date of Patent: May 23, 2017
    Assignee: PERASO TECHNOLOGIES INC.
    Inventors: Grigori Temkine, Craig Farnsworth, Arash Tabibiazar, Alexander Tomkins, Bradley Robert Lynch
  • Patent number: 9634699
    Abstract: Disclosed are an apparatus for controlling a wide-band signal transmission gain, which differently applies a transmission gain by the unit of an intermediate frequency (IF) at a transmitting side of a wide-band multi-IF wireless communication system which can convert multiple baseband digital signals into IF signals and thereafter, multiplex and simultaneously transmit the converted IF signals and a signal processing method of the same.
    Type: Grant
    Filed: February 11, 2016
    Date of Patent: April 25, 2017
    Assignee: ELECTRONICS AND TELECOMMUNICATIONS RESEARCH INSTITUTE
    Inventor: Yong Su Lee
  • Patent number: 9621274
    Abstract: Consistent with the present disclosure a transmitter is provided that transmits data in either a “quasi-DP-BPSK” (“QDP”) mode or in a DP-QPSK mode. In the QDP mode, data bits are transmitted as changes in phase between first and second phase states along a first axis or as changes in phase between third and fourth phase states along a second axis in the IQ plane. Although the transmitter outputs an optical signal that changes in phase between each of the four states, a sequence bit identifies which axis carries the data bit. The sequence bit is one of a series of sequence bits that may be generated by a pseudo-random number generator. The series of sequence bits can be relatively long, e.g., 32 bits, to permit sufficiently random changes in the axis that carries the data.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: April 11, 2017
    Assignee: Infinera Corporation
    Inventors: John D. McNicol, Kuang-Tsan Wu
  • Patent number: 9525390
    Abstract: A switching circuit generates a switching pulse that is pulse modulated according to an input signal. An error amplifier includes a phase compensating filter that generates a feedback signal corresponding to the switching pulse. The error amplifier generates an error signal corresponding to a difference between the input signal and the feedback signal. A pulse modulator includes an oscillator that generates a carrier signal having a variable frequency. The pulse modulator pulse-modulates the carrier signal according to the error signal, so as to generate a pulse modulated signal. The phase compensating filter is configured such that its frequency characteristics can be adjusted according to the frequency of the carrier signal.
    Type: Grant
    Filed: August 19, 2015
    Date of Patent: December 20, 2016
    Assignee: ROHM CO., LTD.
    Inventor: Takayuki Ibusuki
  • Patent number: 9509377
    Abstract: A communication system provides for adaptive rank determination, for example, a rank 2 transmission in instances where a rank 1 transmission may be indicated under supported feedback modes in current standards where no explicit power adaptation can be assumed, for example, where a user equipment (UE) is limited to reporting a rank 1 channel due to a large dynamic range of a signal or due to a signal received by the UE from one base station (BS) antenna port drowning out a signal received by the UE from another BS antenna port. The communication system provides for the UE to implement rank 2 transmission in such instances by using per-antenna port power control at a BS serving the UE. In one embodiment, the BS controls the rank determination at the UE by signaling transmit power or power offset related parameters to use for rank and transmission parameters determination and feedback.
    Type: Grant
    Filed: November 7, 2011
    Date of Patent: November 29, 2016
    Assignee: Google Technology Holdings LLC
    Inventors: Krishna Kamal Sayana, Tyler A. Brown, Robert T. Love, Vijay Nangia