Antinoise Or Distortion Patents (Class 375/278)
  • Patent number: 10375697
    Abstract: Provided are a frequency channel allocating section (10) that allocates frequency channels, a terminal reception quality information processing section (6) that calculates an optimal modulation rate and required transmit power for each subcarrier, a subcarrier power control section (12) that controls a level of transmit power for each subcarrier, and a determining section (10) that checks a reception bandwidth of a communicating apparatus, while determining whether the communicating apparatus is a full band terminal capable of receiving all the frequency channels in the system band or is a limited band terminal capable of receiving only part of frequencies, and when the communicating apparatus is the limited band terminal, the transmit power of all or part of subcarriers is decreased in a frequency channel that is adjacent to a reception band allocated to the communicating apparatus and that is allocated to another communicating apparatus.
    Type: Grant
    Filed: January 28, 2016
    Date of Patent: August 6, 2019
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hiroki Kashiwagi, Yasuhiro Hamaguchi
  • Patent number: 9203680
    Abstract: A system and methods that accommodate for nonlinear interference in a multi-carrier communications system are provided. A first signal is received by a receiver. The first signal comprises a source signal transmitted on a carrier over a communications channel. The first signal reflects a source symbol mapped to one of a plurality of signal constellation points, and each signal constellation point is associated with a different one of a plurality of signal clusters. A received representation of the source signal with respect to the source symbol is acquired from the first signal. A plurality of likelihood metrics are determined, where each likelihood metric is based on the received representation of the source signal with respect to the source symbol and a different one of a plurality of core parameters, wherein each core parameter is based on a centroid estimate with respect to a different one of the signal clusters.
    Type: Grant
    Filed: September 18, 2012
    Date of Patent: December 1, 2015
    Assignee: Hughes Network Systems, LLC
    Inventors: Bassel Beidas, Rohit Iyer Seshadri
  • Patent number: 9036729
    Abstract: A repeater includes a clock-and-data recovery element and a phase interpolator to extract an embedded clock frequency from a data stream. The phase interpolator determine a frequency offset and sends such offset as phase interpolator codes to a filter and scaler. The filtered, scaled phase interpolator codes are used to produce a reference clock frequency for retransmission.
    Type: Grant
    Filed: April 29, 2013
    Date of Patent: May 19, 2015
    Assignee: Avago Technologies General IP (Singapore) Pte. Ltd.
    Inventors: Hiep Pham, Chaitanya Palusa, Tomasz Prokop, Adam Healey
  • Patent number: 9020068
    Abstract: In this VSWR measurement circuit, a power measurement unit measures the power level of a reflected signal which is included in a feedback signal which has been extracted at a second CPL which has been deployed at a position connecting to an antenna end via a cable. To this end, the VSWR measurement circuit is provided with a main signal component removal circuit, wherein the main signal which has been extracted from the prestage of a digital pre-distortion circuit, and a signal in which the feedback signal that had been extracted at the second CPL has been converted to a digital signal at an A/D CONV, are provided as inputs, the main signal component included in the feedback signal is removed, and only the reflected signal is extracted so as to be output to the power measurement unit.
    Type: Grant
    Filed: May 29, 2012
    Date of Patent: April 28, 2015
    Assignee: NEC Corporation
    Inventor: Junji Watanabe
  • Patent number: 9008246
    Abstract: The present technique relates to a transmission device, a transmission method, a reception device, a reception method, a program, and a communication system which can realize a system capable of promptly addressing a newly-generated disturbance wave. A broadcasting device of the present disclosure includes: a reception unit which receives reception interference information notified from the reception device; a setting unit which sets a frequency of a notch to be provided in a transmission signal on the basis of the reception interference information that has been received; a modulation unit which provides the notch in accordance with the set frequency of the notch while at the same time generates a modulated signal by modulating information to be transmitted; and a send-out unit which sends out the modulated signal as the transmission signal.
    Type: Grant
    Filed: March 29, 2012
    Date of Patent: April 14, 2015
    Assignee: Sony Corporation
    Inventors: Hiroo Takahashi, Takahiro Okada
  • Patent number: 9001929
    Abstract: A method and an apparatus for a transmitter to transmit data in a wireless communication system are provided. This method includes: generating a first signal field including at least one symbol; generating a second signal field configured by repeating at least one symbol of the first signal field; and transmitting a frame including the first signal field, the second signal field, and a data field and a first symbol of the second signal field is modulated through binary phase shift keying (BPSK) and symbols from a second symbol of the second signal field are modulated through Q-BPSK. According to the present invention, a service filed can be extended while maintaining compatibility with a wireless communication system in the related art by transmitting a frame using symbol repetition.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: April 7, 2015
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Il Gu Lee, Heejung Yu, Hun Sik Kang, Sok Kyu Lee
  • Patent number: 9001919
    Abstract: A communications system includes a receiver unit connected with a transmission channel. The receiver unit determines a signal power of a first communications signal received over the transmission channel. A transmitter unit is connected with the transmission channel and transmits a second communications signal, wherein a gain of the communications signal being output by the transmitter unit is controllable. A control unit controls the gain of the transmitter unit in response to the determined signal power. At the receiver unit, detection of broadcast signal ingress during data communication is improved and methods for avoiding disturbances between coexisting communications systems may become more reliable. Different distances between successive training symbols suitable for channel estimation may be provided to enhance the noise measurement.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: April 7, 2015
    Assignee: SONY Corporation
    Inventors: Andreas Schwager, Gerd Spalink
  • Patent number: 9001913
    Abstract: A method implemented in a multicarrier transmission system, the method comprising generating a plurality of constellation points by using one or more constellation mappers to map a plurality of special data sequences for an idle data transmission unit (IDTU), wherein the plurality of special data sequences are computed prior to the mapping such that the plurality of constellation points are essentially inner constellation points, wherein each of the inner constellation points resides in a constellation diagram that corresponds to one of a plurality of subcarriers used by the IDTU, and wherein the constellation diagram comprises a number of inner constellation points and a number of outer constellation points, with the inner constellation points being closer from an origin of the constellation diagram than the outer constellation points, and transmitting the plurality of constellation points.
    Type: Grant
    Filed: September 5, 2013
    Date of Patent: April 7, 2015
    Assignee: Futurewei Technologies, Inc.
    Inventors: Ruxiang Wang, Guozhu Long, Yan Zhang, Amir H. Fazlollahi
  • Patent number: 9001947
    Abstract: A receiver includes a first receiver chain configured to receive a first input signal and a second receiver chain configured to receive a second input signal. A first phase predistorter is provided in the first receiver chain and is configured to shift a phase of the first input signal by a first phase shift ??A(f). A combiner is coupled to the first receiver chain and the second receiver chain and combines the first and second input signals. The first phase shift is selected to cause undesired signal components received in the first and second input signals to combine destructively.
    Type: Grant
    Filed: January 10, 2012
    Date of Patent: April 7, 2015
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Mark Wyville
  • Patent number: 8971380
    Abstract: A machine-implemented system and method are described for removing interference between adjacent distributed-input-distributed-output (DIDO) clusters comprising. For example, a method according to one embodiment comprises: detecting signal strength at a first client from a main DIDO cluster; detecting interference signal strength at the first client from an interfering DIDO cluster; if the signal strength from the main DIDO cluster reaches a specified value relative to the value of the interference signal strength from the interfering DIDO cluster, then generating channel state information (CSI) defining channel state between one or more antennas of the first client and one or more antennas of the interfering DIDO cluster; transmitting the CSI from the first client to a base transceiver station (BTS) in the interfering DIDO cluster; and implementing DIDO precoding with inter-DIDO-cluster interference (IDCI) cancellation at the BTS in the interfering DIDO cluster to avoid RF interference at the first client.
    Type: Grant
    Filed: May 1, 2012
    Date of Patent: March 3, 2015
    Assignee: Rearden, LLC
    Inventors: Antonio Forenza, Stephen G. Perlman
  • Patent number: 8958508
    Abstract: A method and system for measuring noise of a machine are disclosed by the present invention, and the method includes: acquiring a first noise interference set, searching for noise interferences which are less than a preset noise interference threshold from the first noise interference set to obtain a second noise interference set, and then calculating an average value of the second noise interference set; and determining whether the average value of the second noise interference set is less than or equal to a set threshold, and if the average value of the second noise interference set is less than or equal to the set threshold, the current noise of the machine is equal to the average value of the second noise interference set. With the present invention, a more accurate measurement value of the noise of the machine can be obtained.
    Type: Grant
    Filed: June 9, 2010
    Date of Patent: February 17, 2015
    Assignee: ZTE Corporation
    Inventors: Xiaoming Su, Yujie Li
  • Patent number: 8908751
    Abstract: One embodiment of the present invention relates to a method and apparatus are provided herein for reducing the power consumption of a transmission chain while maintaining an acceptable figure of merit (e.g., linearity). In one embodiment, an adaptive biasing element is configured to perform adaptive biasing to reduce current consumption of a transmission chain by adjusting the operating point of one or more transmission chain elements (e.g., power amplifier, mixer, etc.). However, since adaptive biasing may reduce the linearity of a transmitted signal, its use is limited by the degradation of figure of merit caused by the introduced non-linearities. Accordingly, a pre-distortion element may be configured to perform adaptive digital pre-distortion (DPD) on a transmission chain input signal to account for non-linearities generated through the adaptive biasing, therefore allowing the adaptive biasing to further reduce the current consumption while maintaining an acceptable figure of merit.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: December 9, 2014
    Assignee: Intel Mobile Communications GmbH
    Inventors: Andrea Camuffo, Chi-Tao Goe, Bernhard Sogl, Sandro Pinarello, Jan-Erik Mueller, Nick Shute
  • Patent number: 8867663
    Abstract: An orthogonal frequency division multiplexing (OFDM) signal transmission apparatus which transmits OFDM signals by using a plurality of transmission antennas includes a subcarrier setting device which sets signals for subcarriers so as to use some of the subcarriers of the OFDM signals as pilot subcarriers to transmit pilot signals and use the remaining subcarriers as data subcarriers to transmit data signals, the subcarrier setting device changing polarities of signals for the pilot subcarriers for each transmission antenna.
    Type: Grant
    Filed: November 18, 2011
    Date of Patent: October 21, 2014
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Tsuguhide Aoki
  • Patent number: 8847751
    Abstract: A first communication apparatus 100 transmits a pilot signal which was generated by a pilot signal generation section 14, at predetermined timing, and detects an unbalance component of a transmission line 300 at the time of pilot signal transmission in an unbalance component detection section 13, and controls a transmission signal in such a manner that an unbalance component is reduced by a transmission control section 12 on the basis of the detected unbalance component.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: September 30, 2014
    Assignee: Panasonic Corporation
    Inventors: Fumio Ichihara, Akihiro Yamashita, Hidekazu Matsunobu, Nobutaka Kodama, Masahiro Maki, Tsunehiro Hanada, Yuji Igata, Toshiyuki Wakisaka, Kazuaki Kusune, Mutsuhiko Oishi, Ryota Yukizane
  • Patent number: 8837633
    Abstract: A communication system includes digital signals that carry data and correspond to channels of a composite signal to be transmitted across a communication channel. Active channels are detected and used to configure digital processing. In one embodiment, active channels are detected, where a particular active channel corresponds to the presence of a particular one of the digital signals. Active channel detection may be used to configure pre-distortion of a composite signal to be transmitted to compensate for distortion in a digital-to-analog converter. Likewise, active channel detection may be used to optimize the configuration of an up-converter. In one embodiment, a programmable device is configured based on detected active channels into a plurality of different configurations.
    Type: Grant
    Filed: October 21, 2011
    Date of Patent: September 16, 2014
    Assignee: Xilinx, Inc.
    Inventor: Christopher H. Dick
  • Publication number: 20140233668
    Abstract: A repeater includes a clock-and-data recovery element and a phase interpolator to extract an embedded clock frequency from a data stream. The phase interpolator determine a frequency offset and sends such offset as phase interpolator codes to a filter and scaler. The filtered, scaled phase interpolator codes are used to produce a reference clock frequency for retransmission.
    Type: Application
    Filed: April 29, 2013
    Publication date: August 21, 2014
    Applicant: LSI Corporation
    Inventors: Hiep Pham, Chaitanya Palusa, Tomasz Prokop, Adam Healey
  • Patent number: 8798199
    Abstract: C-HPA separates an input signal into separated signals, and amplifies and combines the separated signals. The C-HPA includes a plurality of signal splitters, a delay discrepancy estimator, and a delay discrepancy adjuster. Each of the signal splitters splits each of the separated signals into a signal in which a time component of the separated signal is put ahead a predetermined time and a signal in which the time component is delayed the predetermined time, and outputs split signals. The delay discrepancy estimator uses the input signal, the split signals output from each of the signal splitters and the combined output signal to estimate delay discrepancy between the separated signals. The delay discrepancy adjuster uses the estimated delay discrepancy to adjust the delay discrepancy between the separated signals.
    Type: Grant
    Filed: January 17, 2012
    Date of Patent: August 5, 2014
    Assignee: Fujitsu Limited
    Inventor: Alexander N. Lozhkin
  • Patent number: 8792577
    Abstract: Method and apparatus for medium access control in a wireless broadband system with multiuser MIMO/MISO technology comprising the steps of a transmitter (Tx) broadcasting a polling message (1) to all the users (Rx1 . . . Rxi . . . RXN) associated to said transmitter (Tx); the users answering with reply messages (2) during a time slot (61 . . . 6m) randomly selected from a plurality of time slots in which a period of time dedicated to sending reply messages (5) is divided; the transmitter (Tx) performing a scheduling and transmission of data (3); and scheduled users sending Acknowledgment messages (4). Preferably, only users which measure a Signal to Noise plus Interference Ratio over a pre-defined threshold for a transmission beam send reply messages (2).
    Type: Grant
    Filed: June 12, 2009
    Date of Patent: July 29, 2014
    Assignee: Fundacio Privada Centre Tecnologic de Telecomunicions de Catalunya
    Inventors: Christos Verikoukis, Nizar Zorba Barah, Elli Kartsaki, Luis Alonso Zárate
  • Patent number: 8761323
    Abstract: In a receive node of a wireless network, an iterative multi-user multi-stage interference cancellation receiver is used. After each stage of interference cancellation, interference characteristics change. An adaptive strategy is used in which after each stage of interference cancellation, impairment covariance is parametrically updated and combining weights of the receiver are adapted to reflect the updated impairment covariance.
    Type: Grant
    Filed: December 21, 2011
    Date of Patent: June 24, 2014
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Yi-Pin Eric Wang, Gregory Bottomley, Jung-Fu Cheng, Stephen Grant, Ning He, Niklas Johansson, Cagatay Konuskan
  • Patent number: 8744023
    Abstract: Systems and methods are provided for whitening noise of a received signal vector in a multiple-input multiple-output (MIMO) transmission or storage system. The whitening filter may be designed to whiten an interference component of the received signal vector, where the interference component is derived from modeling transmitter and receiver imperfections as a first coupling between MIMO transmitter outputs and a second coupling between MIMO receiver. The whitening filter may be computed based on the covariance matrix of the interference component.
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: June 3, 2014
    Assignee: Marvell International Ltd.
    Inventors: Leilei Song, Rohit U. Nabar, Kedar Shirali
  • Patent number: 8731105
    Abstract: A method and apparatus for modeling distortion of a non-linear device are disclosed. A pre-distorter model has a plurality of branches. Each branch receives a different output basis function signal. At least one branch includes a down-sampler, a memory structure and an up-sampler. The down-sampler down-samples the received output basis function signal received by the branch by a factor of 1/Mk, where Mk is different for each of the at least one branches. The memory structure includes at least one delay element to delay the output of the down-sampler according to a predetermined delay. The memory structure has an output based on an output of the at least one delay element. The up-sampler up-samples the output of the memory structure by the up-sampling factor, Mk.
    Type: Grant
    Filed: June 21, 2012
    Date of Patent: May 20, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventor: Chunlong Bai
  • Publication number: 20140112409
    Abstract: Improving the reliability of digital radio communication affected by multi-path interference under an environment where there are multiple objects that scatter electromagnetic waves is accomplished. A wireless transmitter transmits a first transmission wave having a first carrier frequency (f0+?f), modulated by a modulator with an information signal having a frequency band f1 which is predetermined, from a transmitting antenna, and transmits a second transmission wave having a second carrier frequency (f0??f), modulated by a modulator with such information signal. An average frequency f0 between the first carrier frequency (f0+?f) and the second carrier frequency (f0??f) is kept constant, whereas the first carrier frequency (f0+?f) and the second carrier frequency (f0??f) are varied by controlling a frequency difference ?f to vary.
    Type: Application
    Filed: June 1, 2011
    Publication date: April 24, 2014
    Applicant: Hitachi, Ltd.
    Inventor: Ken Takei
  • Patent number: 8675769
    Abstract: A method and system for optimizing symbol mapping in partial response based communications that are based on use of pulse-shaping that incorporates a predetermined amount of inter-symbol interference (ISI). Optimizing symbol mapping symbol mapping may comprise configuring optimized constellation mapping for use in mapping and/or de-mapping data communicated using the partial response pulse-shaping. In this regard, the optimized constellation mapping may be based on a reference constellation mapping that is utilized for reference modulation scheme, and the configuring comprises applying adjustments to one or more constellation points in the reference constellation mapping. The optimized constellation mapping may be configured to optimize an applicable minimum distance for one or more selected error patterns for a given spectral compression applied during partial response based communications.
    Type: Grant
    Filed: January 31, 2013
    Date of Patent: March 18, 2014
    Assignee: MagnaCom Ltd.
    Inventor: Amir Eliaz
  • Patent number: 8666323
    Abstract: Provided are an RFID reader and a method for suppressing transmission leakage signals thereof. The RFID reader includes a first loop, a second loop, and a digital signal processor. The first loop suppresses a first transmission leakage signal of an RX signal in response to a first leakage control signal. The second loop suppresses a second transmission leakage signal of the RX signal, received through the first loop, in response to a second leakage control signal. The digital signal processor generates the first leakage control signal and the second leakage control signal. The digital signal processor generates the first leakage control signal until the level of the first transmission leakage signal becomes equal to or lower than the level of a first reference transmission leakage signal.
    Type: Grant
    Filed: May 25, 2010
    Date of Patent: March 4, 2014
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Donghan Lee, Sang Gee Kang, Kwang-Soo Cho, Man Sik Park, Chan-Won Park, Cheng-Hao Quan, Ji-Hoon Bae, Gil Young Choi, Jong-Suk Chae
  • Patent number: 8588321
    Abstract: When power scaling is applied to multi-user MIMO, a reduction in transmission rate is suppressed and transmission efficiency is improved. When signals are transmitted through spatial multiplexing from a wireless base station 11 to a plurality of pieces of user equipment 12 and 13, notification of a transmission parameter (MCS) of the distant user equipment (UE-B) 13 is provided as control information to the adjacent user equipment (UE-A) 12. The user equipment 12 calculates, based on the received control information, a reception quality (CQI) after cancellation of a signal serving as an interference signal and destined for the other user equipment 13, and feeds back the calculated result to the wireless base station 11.
    Type: Grant
    Filed: October 23, 2008
    Date of Patent: November 19, 2013
    Assignee: Panasonic Corporation
    Inventors: Masayuki Hoshino, Katsuhiko Hiramatsu, Kenichi Miyoshi
  • Patent number: 8548033
    Abstract: Carrier frequency offset is determined by sample-to-sample phase shifts of a digital radio signal. The CFO range is divided into a number of intervals and creates as many parallel derived streams as there are interval endpoints by pre-compensating (“back rotating”) the input by the sample-to-sample phase shift corresponding to the particular endpoint. Magnitude and phase values are computed of the correlation of a preamble pattern period with the preamble segment of each derived stream in parallel. The largest resulting magnitude value(s) are used to zoom in on the actual CFO present in the input stream. Improved accuracy in the presence of noise may be obtained by repeating the search for a shorter interval centered on the prior CFO value. Final CFO and phase values from corresponding correlation computations then determine the actual CFO and corresponding sample-to-sample phase shift to be applied for pre-compensation (“back rotation”) in an open-loop AFC.
    Type: Grant
    Filed: December 20, 2011
    Date of Patent: October 1, 2013
    Assignee: Microchip Technology Incorporated
    Inventors: Jozsef G. Nemeth, Peter Szilveszter Kovacs
  • Patent number: 8509368
    Abstract: Systems and methods that provide clock jitter compensation architectures that improve the performance of direct radio frequency (RF) receivers by injecting a calibration tone into the received radio frequency (RF) signals in order to help identify and then compensate for the clock jitter noise. After injecting the tone, the jitter noise going through the direct RF bandpass sampling receiver is estimated using a narrow bandwidth filter, and the received signals are further processed and demodulated depending on the Nyquist zone of the received signal. The relative modulation factor for the modulation is computed and then applied to the Nyquist zone to de jitter that particular Nyquist zone.
    Type: Grant
    Filed: December 2, 2009
    Date of Patent: August 13, 2013
    Assignee: L-3 Communications Integrated Systems, L.P.
    Inventors: Gerald L. Fudge, Mark A. Chivers, Sujit Ravindran, Alex Yeh
  • Patent number: 8478210
    Abstract: Power amplifiers (PAs) using a Doherty or other power output level sensitive configuration have been employed for several years in telecommunications (as well as other applications) to take advantage of efficiency gains. For many of these applications, baseband signals are predistorted to compensate for nonlinearities in the PAs, but because there is a “switching event” in a Doherty-type amplifier (for example), the nonlinearities become dynamically varying. As a result, digital predistortion (DPD) becomes increasingly difficult to perform. Here, DPD modules are provided that adapt to changes in dynamically varying PAs based on a determination of the average power or other relevant metric prior to transmission.
    Type: Grant
    Filed: May 10, 2011
    Date of Patent: July 2, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Hardik P. Gandhi, Lei Ding
  • Patent number: 8472990
    Abstract: A method of operating a radio-frequency (RF) circuitry and a signal-processing circuitry in a mobile telephone apparatus includes at least partially disabling the signal-processing circuitry while transmitting or receiving signals. In one example, a processor is efficiently disabled by generating and servicing an interrupt of relatively high priority. One advantage of this example is that preexisting, legacy code can be maintained, while still achieving the desired objectives. The processor can be enabled by generating and servicing a second high priority interrupt.
    Type: Grant
    Filed: July 23, 2004
    Date of Patent: June 25, 2013
    Assignee: St Ericsson SA
    Inventors: Frederick A. Rush, G. Diwakar Vishakhadatta, Phillip M. Matthews
  • Patent number: 8457239
    Abstract: The method is for managing operation of a first apparatus belonging to a first communication system and exchanging within the first communication system a multi-carrier modulated signal on several sub-carriers. The method includes detecting at the first apparatus the presence of an interfering signal emitted from a victim apparatus on a sub-carrier. The method may also include determining at the first apparatus the path loss between both apparatuses, determining from the path loss and from an allowed interference level at the victim apparatus a maximum allowed transmit power on the sub-carrier of a multi-carrier modulated signal to be transmitted from the first apparatus, and adjusting within the first apparatus the processing of the multi-carrier modulated signal to be transmitted in accordance with the maximum allowed transmit power.
    Type: Grant
    Filed: October 15, 2007
    Date of Patent: June 4, 2013
    Assignee: STMicroelectronics N.V.
    Inventors: Friedbert Berens, Andreas Rüegg
  • Patent number: 8442146
    Abstract: Apparatus and methods for use in a wireless communication system are disclosed for reducing channel estimation noise in a device such as a wireless transceiver. A disclosed apparatus includes a processor that determines a channel activity portion and a noise portion of a channel estimation. The processor also determines a threshold noise level based on channel estimate values in the noise portion of the channel estimation. The processor compares channel estimate energy values in the channel estimation to the threshold noise level and sets each of the channel estimate energy values being less than the threshold noise level to a predetermined value such as zero in order to reduce or eliminate the noise. Similar methods are also disclosed.
    Type: Grant
    Filed: October 25, 2010
    Date of Patent: May 14, 2013
    Assignee: Qualcomm Incorporated
    Inventor: Michael Mao Wang
  • Patent number: 8441912
    Abstract: A first device receives a first signal transmitted over a transmission line from a second device. The first signal is processed and information is generated that is related to crosstalk from other transmission lines. The information is modulated onto at least one carrier of a plurality of carriers of a second signal to be transmitted from the first device to the second device.
    Type: Grant
    Filed: September 18, 2006
    Date of Patent: May 14, 2013
    Assignee: Lantiq Deutschland GmbH
    Inventor: Axel Clausen
  • Patent number: 8433271
    Abstract: One aspect of the present invention is directed to an apparatus to perform impulse blanking of a received signal at multiple locations of a signal processing path. To effect such impulse blanking, multiple impulse detectors and blankers may be present, in addition to other circuitry. The impulse detectors may operate at different bandwidths, and the impulse blankers may be located at different locations of the signal processing path and may be differently configured.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: April 30, 2013
    Assignee: Silicon Laboratories Inc.
    Inventor: Junsong Li
  • Patent number: 8406113
    Abstract: A wireless transmitter exhibits improved power de-rating reduction, which improves the power efficiency of non-constant envelop communication systems by mapping N first samples of a first discrete Fourier transform (DFT) of a group of coded symbols to M sub-carriers according to a first sub-carrier mapping rule (212), performing a first inverse DFT (IDFT) on the M sub-carriers to provide M second samples (214), clipping the M second samples according to a clipping rule to provide M third samples (216), performing a second DFT on the M third samples (218), and applying a frequency domain mask to generate M clipped samples (220) which may be mapped to O subcarriers according to a predetermined second subcarrier mapping rule. The transmitter may be advantageously implemented within a single carrier transmission scheme, such as a single carrier-frequency division multiple access (SC-FDMA) uplink transmission scheme.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: March 26, 2013
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Chunming Zhao, Ning Chen
  • Patent number: 8379770
    Abstract: System for converting a radiofrequency signal SRX so as to recover encoded information carried by the signal SRX, includes generating elements arranged to generate a signal SLO, mixing elements (3) arranged to generate a signal SRX-LO by mixing the signal SRX with the signal SLO, an analog/digital converter arranged to convert the signal SRXLO into a digital signal SRX-LO-Num, a device generating an error correction digital signal SCor, the device being arranged so that the signal SCor reflects the phase gap between the phase of the signal SLO and a phase setpoint, the phase setpoint being the phase of an ideal signal S0, ideal for recovering the encoded information carried by the signal SRX, combining elements arranged to generate the signal S0?-Num by combining the signal SRX-LO-Num with the signal SCor. A system for converting a digital signal so as to send a radiofrequency analog signal carrying the information of the digital signal is also described.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: February 19, 2013
    Assignee: Nanoscale Labs
    Inventors: Nicolas Sornin, Laurent Perraud
  • Patent number: 8369788
    Abstract: A method for reducing inter-cell interference and a method for transmitting a signal by a collaborative MIMO scheme, in a communication system having a multi-cell environment are disclosed. An example of a method for transmitting, by a mobile station, precoding information in a collaborative MIMO communication system includes determining a precoding matrix set including precoding matrices of one more base stations including a serving base station, based on signal strength of the serving base station, and transmitting information about the precoding matrix set to the serving base station. A mobile station in an edge of a cell performs a collaborative MIMO mode or inter-cell interference mitigation mode using the information about the precoding matrix set collaboratively with neighboring base stations.
    Type: Grant
    Filed: December 29, 2008
    Date of Patent: February 5, 2013
    Assignee: LG Electronics Inc.
    Inventors: Jae Wan Kim, Wook Bong Lee, Su Nam Kim, Dong Guk Lim, Bin Chui Ihm
  • Patent number: 8331508
    Abstract: A narrowband interference (NBI) canceller is coupled to an A/D converter to receive an input signal and supply an NBI-canceled signal to an error correcting decoder. In the NBI canceller, a first arithmetic unit receives the input signal and a predicted-interference signal, and supplies a difference thereof as the interference-canceled signal. A slicer receives the interference-canceled signal and supplies a decision signal. A second arithmetic unit subtracts the decision signal from the input signal to generate a noise signal. A coarse frequency estimator receives the noise signal and analyzes the frequency spectrum to generate a coarse estimate of a fundamental frequency of the NBI. The coarse estimate is used by an adaptive narrowband interference predictor to generate the predicted-interference signal while adaptively tracking the narrowband interference. Use of the NBI canceller in a transceiver can eliminate link drop caused by operation of wireless devices that generate EMI in a cable.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: December 11, 2012
    Assignee: Applied Micro Circuits Corporation
    Inventor: Dariush Dabiri
  • Patent number: 8331738
    Abstract: What is disclosed is a novel system and method for reducing a size of a memory buffer used by an electronic registration correction system performing an electronic registration correction on a digital image. The present method uses column address segmentation to identify blocks of scanlines within a spatially mapped array of image pixels comprising a digital image. Advantageously, the present system and method reduces scanline buffer memory by a factor of 2n-1, where n is the number of column address segments. Buffering can be performed at almost any upstream location in the image path. The present method is well suited for high resolution imaging equipment where memory is constrained by design, cost, or space limitations.
    Type: Grant
    Filed: March 24, 2010
    Date of Patent: December 11, 2012
    Assignee: Xerox Corporation
    Inventors: Paul A. Hosier, Jess R. Gentner, Kenneth R. Miller
  • Patent number: 8320477
    Abstract: An inter-carrier interference ICI cancellation method of a kth sub-carrier of an orthogonal frequency division multiplexing OFDM receiving signal (k is a natural number greater than 1 and less than or equal to n, n is a number of sub-carriers) includes canceling an inter-carrier interference element produced by at least one sub-carrier among inter-carrier interference elements of the kth sub-carrier by a decision feedback equalization DFE method, and canceling another inter-carrier interference element produced by at least another sub-carrier among inter-carrier interference elements of the kth sub-carrier by a linear minimum mean square error equalization LMMSE method.
    Type: Grant
    Filed: October 24, 2008
    Date of Patent: November 27, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Sergey Zhidkov, Guangbui Liu, Jinhee Cheon
  • Patent number: 8290457
    Abstract: One aspect of the present invention is directed to an apparatus to perform impulse blanking of a received signal at multiple locations of a signal processing path. To effect such impulse blanking, multiple impulse detectors and blankets may be present, in addition to other circuitry. The impulse detectors may operate at different bandwidths, and the impulse blankers may be located at different locations of the signal processing path and may be differently configured.
    Type: Grant
    Filed: April 27, 2010
    Date of Patent: October 16, 2012
    Assignee: Silicon Laboratories Inc.
    Inventor: Junsong Li
  • Patent number: 8233564
    Abstract: A unique digital compression technology for increasing the information carrying capacity of a bandwidth limited communications path highway by using a combined coding and modulation technique. The inventive technology allows multiple independent modulated data streams to simultaneously and instantaneously share the same bandwidth without cross-channel interference. A matched filter is used to substantially reduce the error rate and utilizes a unique training method based on performing a spectral response test. An algorithm calculates the effect of the unique characteristics of the communications highway on the transmitted signal and generates an ideal signal stored in the matched filter for comparison with received signals.
    Type: Grant
    Filed: August 4, 2011
    Date of Patent: July 31, 2012
    Assignee: Digital Compression Technology LP
    Inventors: Elliot L. Gruenberg, Patrick Antaki, Dhadesugoor Vaman, David N. Judelson
  • Patent number: 8199835
    Abstract: Systems and methods for adaptive signal sampling and sample quantization for resource-constrained stream processing. Exemplary embodiments include a signal sampling and signal quantization method for a data stream from a ECG sensor into a pervasive device, the method including adaptively sampling the data stream, compressing data samples from the data stream, reducing the number of samples via quantization, defining a utility function for signal reconstruction, and formulating optimization on the reconstructed signal that is jointly sampled and quantized.
    Type: Grant
    Filed: May 30, 2007
    Date of Patent: June 12, 2012
    Assignee: International Business Machines Corporation
    Inventors: Lisa Amini, Daby M. Sow, Deepak S. Turaga, Olivier Verscheure
  • Patent number: 8184737
    Abstract: Disclosed herein is an echo cancellation and echo channel estimation system that can relay transmit signals without interference with echo signals by canceling the undesired echo signals received by a relay. The echo cancellation and echo channel estimation system is designed to relay signals between a transmitter and a receiver through a relay using multiple antennas. The echo cancellation and echo channel estimation system includes a receive antenna, a preprocessing vector generation module, an echo cancellation module, and a transmit array antenna. The receive antenna receives a transmit signal from the transmitter and an echo signal via an echo channel. The preprocessing vector generation module generates a preprocessing vector and applies the preprocessing vector, the transmit signal and the echo signal, received from the receive antenna, to the echo cancellation module.
    Type: Grant
    Filed: June 12, 2008
    Date of Patent: May 22, 2012
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Yong-Hoon Lee, Jin-Gon Joung, Eui-Rim Jeong
  • Patent number: 8184736
    Abstract: Methods and apparatuses for encoding a plurality of bits into a plurality of pairs of simultaneous electrical pulses.
    Type: Grant
    Filed: October 2, 2007
    Date of Patent: May 22, 2012
    Assignee: Infineon Technologies Austria AG
    Inventor: Martin Feldtkeller
  • Patent number: 8155180
    Abstract: A system includes a programmable transmitter device (e.g., a PLD) connected to a programmable receiver device (e.g., another PLD) via a transmission medium for transmitting a high-speed data signal from the transmitter to the receiver. During a test mode of operation a low-speed communication link between the transmitter and receiver allows those devices to work together to transmit test signals having known characteristics from the transmitter to the receiver via the transmission medium, to analyze the test signals as received by the receiver, and to adjust at least some aspect of the system (e.g., equalizer circuitry in the receiver) to at least partly compensate for losses in the test signals as received by the receiver.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: April 10, 2012
    Assignee: Altera Corporation
    Inventors: Wilson Wong, Sergey Shumarayev, Rakesh Patel
  • Patent number: 8149937
    Abstract: The invention provides a signal receiver. The signal receiver comprises a carrier removal module, a Fast Fourier Transformation (FFT) module, and a signal processor. The carrier removal module generates a carrier signal with a frequency of an estimated carrier frequency, generates at least one delta carrier signal with a frequency of the carrier frequency plus a delta frequency, removes the carrier signal from a first signal to obtain a second signal, and removes the delta carrier signal from the first signal to obtain a third signal. The FFT module derives a series of first FFT values from the second signal, and derives a series of second FFT values from the third signal.
    Type: Grant
    Filed: January 18, 2011
    Date of Patent: April 3, 2012
    Assignee: Mediatek Inc.
    Inventor: Kun-Tso Chen
  • Patent number: 8139679
    Abstract: A system and method for controlling modulation. The system includes a plurality of modulators and a transmitting unit. The plurality of modulators decodes data from a data signal and also encodes the data into a clock signal. The transmitting unit transmits the encoded clock signal. According to the system and method disclosed herein, the present invention provides optimized coding efficiency while minimizing overall power consumption.
    Type: Grant
    Filed: October 21, 2008
    Date of Patent: March 20, 2012
    Assignee: Atmel Corporation
    Inventors: Mikhail Itskovich, Daniel S. Cohen
  • Patent number: 8140122
    Abstract: An apparatus and a method for determining a multi-antenna transmission mode at a base station in a multi-antenna system are provided. The method for determining the multi-antenna transmission mode includes when using a Multiple Input Multiple Output (MIMO) transmission mode as a multi-antenna transmission mode, determining a reference set point; updating a set point for transmit power control of a terminal according to an error occurrence of a signal received from the terminal; determining whether a channel to the terminal is a channel for applying the MIMO transmission mode by comparing the updated set point with the reference set point; and when the channel to the terminal is not a channel for applying the MIMO transmission mode, changing the multi-antenna transmission mode to a fixed transmission mode.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: March 20, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Byung-Joon Park, Myung-Kwang Byun, Jeong-Tae Oh, Sung-Kwon Jo
  • Patent number: 8135079
    Abstract: The present invention relates an apparatus and method of estimating a signal-to-noise ratio (SNR) of a received signal when the received signal has a timing offset. An apparatus for estimating a signal-to-noise ratio (SNR) according to an exemplary embodiment of the present invention includes a fast Fourier transform (FFT) unit that performs a fast Fourier transform on a received signal to convert the received signal into a frequency domain signal; a preamble selector that extracts a preamble from the frequency domain signal; a correlator that correlates the preamble to a preamble reference signal generated by a receiver to calculate a correlation value; an entire power estimator that calculates entire power; a noise power estimator that applies a differential demodulation method to the correlation value to remove a timing offset and calculate noise power; and an estimating unit that uses the entire power and the noise power to estimate the signal-to-noise ratio (SNR).
    Type: Grant
    Filed: July 22, 2008
    Date of Patent: March 13, 2012
    Assignees: Samsung Electronics Co., Ltd., Electronics and Telecommunications Research Institute
    Inventors: Hyeong Sook Park, Jun-Woo Kim, Eon Young Hong, Youn Ok Park
  • Patent number: 8130878
    Abstract: An apparatus and method for estimating a carrier-to-interference-and-noise ratio (CINR) of a received signal in an orthogonal frequency division multiplexing (OFDM) system are provided. A band-pass filter attenuates a signal region of the received signal and passes a signal in a noise region. A first power calculator calculates interference and noise power of the noise-region signal received from the band-pass filter. A second power calculator calculates total received power of the received signal. A ratio calculator calculates a CINR based on the interference and noise power, and the total received power.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: March 6, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seong-Wook Song, Jae-Hwan Chang, Young-Mo Gu