Using Plural Separate Signal Paths Patents (Class 455/303)
  • Patent number: 8483260
    Abstract: A method and apparatus for reducing the computational load associated with computing weighting factors for wireless signals received at a wireless receiver is disclosed herein. The method and apparatus reuses a covariance factor matrix to compute multiple sets of weighting factors for multiple received signals. Particular embodiments factor a covariance matrix determined for a first received signal to determine a covariance factor matrix, and use the covariance factor matrix to determine a set of weighting factors for the first received signal as well as to determine additional sets of weighting factors for one or more additional received signals. The different received signals may be associated with different times, different channelization codes, and/or different frequencies. The weighting factors may be used to weight and combine received signals in a GRAKE receiver or chip equalizer. The weighting factors may also be used to determine a signal quality metric.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: July 9, 2013
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventor: Anders Rosenqvist
  • Patent number: 8472566
    Abstract: An apparatus and method for reducing pilot overhead in a multi-antenna system are provided. The method generates postcodes and pre-codes for streams used to transmit signals to at least two receivers. The method allocates a pilot signal to at least one of the streams, and allocates an additional pilot signal shared by at least one of the streams. The method precodes the pilot signal allocated to at least one of the streams, the additional pilot signal, and data to be transmitted to each of the receivers, based on the pre-code for each of the streams, prior to transmission.
    Type: Grant
    Filed: April 16, 2009
    Date of Patent: June 25, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Eun-Seok Ko, Eun-Yong Kim, Yung-Soo Kim
  • Patent number: 8457264
    Abstract: A radio receiver includes a first diversity antenna structure, a second diversity antenna structure, a first RF receiver section, a second RF receiver section, a combining module, and a baseband processing module. The first diversity antenna structure provides the received inbound RF signals from one of the plurality of first antennas based on a first antenna selection signal to produce first received inbound RF signals. The second diversity antenna structure provides the received inbound RF signals from one of the plurality of second antennas based on a second antenna selection signal to produce second received inbound RF signals. The first and second RF receiver sections are operably coupled to convert the first and second received inbound RF signals into first and second inbound baseband signals, respectively. The combining module combines the first and second inbound baseband signals to produce inbound baseband signals.
    Type: Grant
    Filed: September 17, 2004
    Date of Patent: June 4, 2013
    Assignee: VIXS Systems, Inc.
    Inventors: James Ward Girardeau, Jr., Paul Morris Astrachan, Mathew A. Rybicki, Bojan Subasic
  • Patent number: 8452251
    Abstract: A preselector amplifier system and method including of various components is described. The various components may include a vector generator, an active power splitter, an active power combiner, or the like. The preselector amplifier may be integral to and/or coupled to a communications system. The communications system may be at least one of a transceiver, receiver and/or transmitter. The communications system may transmit radio frequency (RF) signals.
    Type: Grant
    Filed: April 13, 2010
    Date of Patent: May 28, 2013
    Assignee: ViaSat, Inc.
    Inventor: David R. Saunders
  • Patent number: 8428541
    Abstract: A method for choosing at least one signal path is disclosed and may include determining a power level characteristic for each of a plurality of signal paths. The determined power level characteristic for each of the plurality of signal paths may be modified. At least one of the plurality of signal paths may be selected for receiving a signal. The selecting may be based on at least one of the modified power level characteristics. The method may also include cycling through at least one of the signal paths. The power level characteristic for each of the plurality of signal paths may be biased. The power level characteristic for each of the plurality of signal paths may be increased by a fixed amount.
    Type: Grant
    Filed: March 16, 2010
    Date of Patent: April 23, 2013
    Assignee: Broadcom Corporation
    Inventors: Rajendra Tushar Moorti, Min Chuin Hoo, Jason Alexander Trachewsky
  • Patent number: 8412118
    Abstract: An integrated circuit radio transceiver and method therefor comprises a receiver front end that further includes a plurality of in-phase and quadrature phase receive processing block operable at first and second frequency bands wherein each of the receive processing blocks defines an ingoing signal path and further includes a plurality of filtering and amplification blocks disposed within the corresponding ingoing signal path, a plurality of RSSI blocks coupled to receive an ingoing analog signal from a corresponding plurality of nodes disposed throughout the ingoing signal path, each of the plurality of received signal strength indicator blocks producing a signal strength indication, and wherein a baseband processor is operable to receive a selected signal strength indication and to produce at least one gain setting to at least one amplification block within the in-phase or quadrature phase receive processing blocks.
    Type: Grant
    Filed: February 22, 2010
    Date of Patent: April 2, 2013
    Assignee: Broadcom Corporation
    Inventors: Adedayo Ojo, Arya Reza Behzad
  • Patent number: 8411777
    Abstract: A wireless communications device having a complex vector quantization codebook for use in a downlink multi-user MIMO (multiple-input-multiple-output) mobile broadcast system with feedback enables the interference between data simultaneously sent by the base station to a plurality of mobile terminals to be reliably minimized. The codebook contains many subsets of code vectors that are substantially mutually (i.e., pairwise) orthogonal, or almost orthogonal, to each other. With use of such a codebook, a base station can transmit simultaneously to subsets of mobile terminals associated with these subsets of code vectors with minimal interference therebetween.
    Type: Grant
    Filed: June 22, 2007
    Date of Patent: April 2, 2013
    Assignee: Alcatel Lucent
    Inventor: Alexei Ashikhmin
  • Patent number: 8401480
    Abstract: A method for performing a Coordinated Multi-Point (CoMP) operation and transmitting feedback information in a wireless communication system is disclosed. The method includes measuring interference levels or noise and interference variances of reference signals received from one or more neighbor cells, and transmitting to a serving Base Station (BS) information about the measured interference levels or noise and interference variances, and information about a Precoding Matrix Index (PMI) that a mobile station (MS) wants to restrict or recommend for a neighbor cell performing the CoMP operation.
    Type: Grant
    Filed: March 4, 2010
    Date of Patent: March 19, 2013
    Assignee: LG Electronics Inc.
    Inventors: Ja Ho Koo, Jian Xu, Bin Chul Ihm, Jae Hoon Chung, Hyun Soo Ko, Moon Il Lee
  • Patent number: 8396095
    Abstract: The present invention relates to a method for decoding a composite radio signal at a receiver in an OFDM based radio communication system, said composite radio signal being a superposition of at least two signals sent by at least one transmitter, each signal having signal properties, in particular modulation scheme, coding scheme, said at least two signals being transmitted using the same radio resource on a set of frequency subchannels of said OFDM system. According to the present invention, the method comprises the steps of: gathering at said receiver information on said signal properties of the respective signals comprised in said composite radio signal; selecting, depending on said signal properties of said respective signals, the signal to be decoded first out of said composite radio signal; decoding said signal to be decoded first according to its signal properties, and subtracting the contribution of said signal to be decoded first from said composite radio signal.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: March 12, 2013
    Assignee: Alcatel Lucent
    Inventors: Andreas Rüegg, Joerg Schaepperle
  • Patent number: 8385255
    Abstract: Using as a reference a known signal assigned to one of a plurality of streams that constitute a packet signal, a control unit applies a cyclic timing shift to known signals assigned to the other streams so as to produce packet signals which are to be transmitted finally. While varying the amount of timing shift, the control unit produces a plurality of packet signals and appends an identification number, with which to uniquely identify each of the plurality of produced packet signals, to each of the packet signals. A baseband processing unit and the like transmit, as a transmission rate inquiry signal, a packet signal constituted by a plurality of streams where the amounts of timing shift are made to differ, and receive a response signal to which the same identification number is appended for the inquiry signal.
    Type: Grant
    Filed: September 19, 2006
    Date of Patent: February 26, 2013
    Assignee: Hera Wireless S.A.
    Inventors: Yasuhiro Tanaka, Seigo Nakao
  • Patent number: 8358614
    Abstract: A method and an apparatus for uplink transmission using multiple uplink carriers are disclosed. A wireless transmit/receive unit (WTRU) selects a dedicated channel medium access control (MAC-d) flow with highest priority data to be transmitted and performs uplink carrier selection and enhanced dedicated channel (E-DCH) transport format combination (E-TFC) restriction and selection to select a carrier among a plurality of carriers and select an E-TFC based on a maximum supported payload, a remaining scheduled grant payload of the selected carrier and a remaining non-scheduled grant payload. The WTRU then generates a medium access control (MAC) protocol data unit (PDU) for E-DCH transmission via the selected carrier based on the selected E-TFC.
    Type: Grant
    Filed: October 31, 2009
    Date of Patent: January 22, 2013
    Assignee: InterDigital Patent Holdings, Inc.
    Inventors: Diana Pani, Paul Marinier, Christopher R. Cave, Benoit Pelletier, Fengjun Xi
  • Patent number: 8358994
    Abstract: In one embodiment, a method for processing radio frequency signals includes estimating an average value of a demodulated signal and a noise signal, both obtained from a radio frequency signal, estimating a noise floor based on the noise signal, generating a blend control signal based on the average values and the noise floor, and blending at least two path signals based on the blend control signal to obtain a blended signal. This blended signal may be output for further processing when multipath noise is detected.
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: January 22, 2013
    Assignee: Silicon Laboratories Inc.
    Inventor: Junsong Li
  • Patent number: 8355430
    Abstract: An embodiment of the invention pertains to demodulating a data communication into a sequence of symbols. In this embodiment, a first filter generates a first convolution between a first plurality of coefficients and the data communication. The data communication is a distortion of a first sequence of symbols selected from a plurality of symbols in a constellation. A first error circuit maps the first convolution to a second sequence of symbols. An adaption circuit adjusts the first coefficients until a convergence at a last one of the symbols in the second sequence. A second filter generates a second convolution between a second plurality of coefficients and the data communication. The second coefficients are initialized to the first coefficients from the adaption circuit. A second error circuit maps the second convolution to a third sequence of symbols.
    Type: Grant
    Filed: January 6, 2011
    Date of Patent: January 15, 2013
    Assignee: Xilinx, Inc.
    Inventor: Christopher H. Dick
  • Patent number: 8345806
    Abstract: An apparatus and a method are provided for detecting N number of TX signals in a MIMO wireless communication system. The apparatus includes an RF processor, a channel estimator, and a signal detector. The RF processor converts signals, received through multiple antennas, into baseband signals. The channel estimator estimates channel information of the respective antennas by using the received signals. The signal detector arranges the baseband signals of the respective antennas on the basis of the channel information, calculates a threshold value of each stage, and selects symbols with a cumulative metric smaller than or equal to the threshold value as candidates at each stage, to detect a TX signal vector with N number of symbols.
    Type: Grant
    Filed: May 28, 2008
    Date of Patent: January 1, 2013
    Assignees: Samsung Electronics Co., Ltd., ICU Research and Industrial Cooperation Group
    Inventors: Sung-Yoon Jung, Sang-Boh Yun, Young-Hoon Kwon, Sung-Soo Hwang, Jong-Ho Lee, Hyun-Cheol Park, Hyoun-Kuk Kim, Ki-Hwan Jeon
  • Patent number: 8340573
    Abstract: A payload system for satellites comprising transponder devices with an input section including an uplink antenna, a low noise amplifier, and a converter, and an output section including an input filter, a high power amplifier, an output filter, and a downlink antenna. At least some of the transponders share their high power amplifiers and the high power amplifiers shared have a maximum power smaller than the total power which can be transmitted by the payload.
    Type: Grant
    Filed: September 25, 2007
    Date of Patent: December 25, 2012
    Assignee: Eutelsat S A
    Inventors: Hector Fenech, Emmanuel Lance
  • Patent number: 8331511
    Abstract: An aspect of the present invention is drawn to a receiver operable to receive a first signal transmitted on a first carrier and to receive a second signal transmitted on a second carrier. The receiver includes a first filter, a second filter and a nonlinear compensator. The first filter is arranged to receive the first signal and to generate a first filtered signal. The second filter is arranged to receive the second signal and to generate a second filtered signal. The nonlinear compensator is arranged to output a first compensating signal based on the first filtered signal and the second filtered signal and to output a second compensating signal based on the first filtered signal and the second filtered signal. Further, the nonlinear compensator can reduce one of nonlinear interference within the first filtered signal and nonlinear interference between the first filtered signal and the second filtered signal.
    Type: Grant
    Filed: December 14, 2009
    Date of Patent: December 11, 2012
    Assignee: Hughes Network Sysetms, LLC
    Inventors: Bassel Beidas, Rohit Iyer Seshadri
  • Patent number: 8315562
    Abstract: A method for improving RFID readers includes transmitting an outgoing RF signal to an antenna through a directional device, and generating a demodulated vector signal from an RF signal related to the RF signal received from the receiver. The method also includes setting the impedance of a controllable-variable-reflectance element with control-parameters from a memory circuit. The memory circuit includes a look up table having therein a corresponding relationship between the control-parameters and an error vector related to the demodulated vector signal.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: November 20, 2012
    Assignee: Symbol Technologies, Inc.
    Inventors: Mark Duron, Richard T. Knadle, Jr.
  • Patent number: 8301095
    Abstract: A portable wireless device that makes it possible to maintain any desired matching state and can suppress an increase in the loss accompanying matching if the impedance characteristic of an antenna changes with expansion/storage of the antenna, deformation of a housing, etc., is provided. Two channels of signal paths that can be selected by switch section 11, 15 are provided between an antenna 10 and a reception circuit 16; a first low noise amplifier 13 that can amplify a received high frequency signal is provided in one path and a second low noise amplifier 18 having an impedance characteristic different from the low noise amplifier 13 is provided in the other signal path. The form of the antenna 10 or the form of a housing is detected in a form change detection section 20 and the two channels of signal paths are automatically switched in a control section and two types of impedance matching states are used properly.
    Type: Grant
    Filed: February 23, 2009
    Date of Patent: October 30, 2012
    Assignee: Panasonic Corporation
    Inventors: Yoshihiro Kanasaki, Haruhiko Kakitsu
  • Patent number: 8285240
    Abstract: Receiver architectures and methods of processing harmonic rich input signals employing harmonic suppression mixers are disclosed herein. The disclosed receivers, mixers, and methods enable a receiver to achieve the advantages of switching mixers while greatly reducing the mixer response to the undesired harmonics. A harmonic mixer can include a plurality of mixers coupled to an input signal. A plurality of phases of a local oscillator signal can be generated from a single local oscillator output. Each of the phases can be used to drive an input of one of the mixers. The mixer outputs can be combined to generate a frequency converted output that has harmonic rejection.
    Type: Grant
    Filed: April 29, 2009
    Date of Patent: October 9, 2012
    Assignee: MaxLinear, Inc.
    Inventors: Kishore Seendripu, Raymond Montemayor, Sheng Ye, Glenn Chang, Curtis Ling
  • Patent number: 8280334
    Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.
    Type: Grant
    Filed: March 15, 2012
    Date of Patent: October 2, 2012
    Assignee: American Radio LLC
    Inventor: Robert Hotto
  • Patent number: 8260230
    Abstract: A radio receiver may comprise a receiver adaptable for receiving a plurality of broadcast streams over a plurality of broadcast channels, wherein the receiver will attempt to receive a selected broadcast stream on a selected broadcast channel, and if the selected broadcast stream is not receivable on the selected broadcast channel, the receiver will attempt to receive the selected broadcast stream on an alternative broadcast channel. A computer readable medium may allow a user of a receiver to create a composite stream comprising at least one portion selected from each of at least two of a plurality of broadcast streams. A method of open interface merge replication may involve comparing data between first and second databases, and if a conflict exists, updating one of the first and second databases with at least a portion of data from the other of the first and second databases to resolve the conflict.
    Type: Grant
    Filed: August 29, 2008
    Date of Patent: September 4, 2012
    Assignee: Clear Channel Management Services, Inc.
    Inventors: Jeffrey D. Zigler, Kevin R. Lockhart, Richard D. Wooden, Jacqueline J. Lockhart, Theodore N. Myers, Evan A. Hill, Tanya R. Jellison
  • Patent number: 8260234
    Abstract: Apparatus and method for calibration in a multi-antenna system are provided. The method includes setting at least two transmission paths connected to antennas, respectively, as reference transmission paths, when receiving compensation signals transmitted in the reference transmission paths in at least two reception paths connected to the antennas, respectively, determining a phase difference of the reception paths using the received compensation signals, and calibrating the reception paths using the phase difference of the reception paths.
    Type: Grant
    Filed: January 23, 2009
    Date of Patent: September 4, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Heon-Ki Chae, Keun-Chul Hwang, Soon-Young Yoon, Seok-Wan Rha
  • Patent number: 8243864
    Abstract: A technique for noise reduction in a wireless communication system uses controllable bandwidth filters (120) to filter a received signal. In a typical implementation, the filters (120) are used at baseband frequencies. A measurement (RSSI) is indicative of the strength of the received signal. A control circuit (144) generates a control signal (146) to control the bandwidth of the filters (120). If the received signal strength is above a first threshold, a wider bandwidth may be used for the filters (120). If the received signal is below a second threshold, the control circuit (144) generates the control signal (146) to set the filters (120) to a more narrow bandwidth. The system (100) may also be used with digital filters (150, 152) following digitization by analog to digital converters (ADCs) (130, 132). The system (100) is particularly well-suited for operation with noise-shaped ADCs (130, 132), such as Delta-Sigma converters.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: August 14, 2012
    Assignee: QUALCOMM, Incorporated
    Inventors: Steven Ciccarelli, Arun Raghupathy, Brian C. Banister
  • Patent number: 8238856
    Abstract: A wireless communicating apparatus is provided which includes two receiving methods, and can determine a favorable receiving method. The wireless communicating apparatus executes, which is provided with the two receiving methods of a first receiving method which is used in a propagation path environment in which it is necessary to reduce the multi-path interference, and a second receiving method which is used in the propagation path environment in which it is not necessary to reduce the multi-path interference, a first determination (step S1) for determining whether or not the fluctuation in time for the path is less than a predetermined threshold, and a second determination (step S2) for determining whether or not the number of the paths is less than a predetermined threshold, and determines (step S3, 4) to use which receiving method of the first receiving method or the second receiving method to communicate via wireless according to a first determination result and a second determination result.
    Type: Grant
    Filed: February 28, 2007
    Date of Patent: August 7, 2012
    Assignee: NEC Corporation
    Inventor: Ayumu Yagihashi
  • Patent number: 8238410
    Abstract: A positioning system receiver that mitigates narrowband interference by dynamically choosing the mitigation technique that yields the best interference mitigation capability with the least signal degradation to maximize receiver performance parameters such as receiver sensitivity, multipath resolution, and low power.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: August 7, 2012
    Assignee: CSR Technology Inc.
    Inventor: Gary Lennen
  • Patent number: 8213881
    Abstract: A signal processing system is disclosed. The system includes: a first synthesizer and a second synthesizer, for respectively generating a first frequency and a second frequency; a first RF circuit; a first analog front end (AFE); a second RF circuit; and a second AFE, wherein the first RF circuit and the first AFE can support a signal transmission of a first bandwidth, the second RF circuit and the second AFE can support a signal transmission of a second bandwidth, a central frequency of the first bandwidth is substantially equal to the first frequency, and a central frequency of the second bandwidth is substantially equal to the second frequency.
    Type: Grant
    Filed: November 21, 2007
    Date of Patent: July 3, 2012
    Assignee: Realtek Semiconductor Corp.
    Inventors: Kuang-Yu Yen, Chung-Yao Chang
  • Patent number: 8190094
    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: January 6, 2012
    Date of Patent: May 29, 2012
    Assignee: LG Electronics Inc.
    Inventors: Jae Wan Kim, Wook Bong Lee, Su Nam Kim, Dong Guk Lim, Bin Chul Ihm
  • Patent number: 8170487
    Abstract: Some embodiments provide a method, system, and apparatus for interference cancellation at the baseband of a receiver. A wireless communication device, having a transmitter and receiver, is provided with an adaptive circuit that cancels interference caused by transmit signals (or other signals) leaked or bled onto the receiver at baseband to facilitate detection of a received signal of interest. Some implementations provide for a circuit that approximately reconstructs the second and third order components caused by the nonlinear response of the down-conversion chain of a receiver. This reconstructed signal is then subtracted from the composite received signal to obtain a received signal of interest.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: May 1, 2012
    Assignee: QUALCOMM, Incorporated
    Inventors: Gurkanwal S. Sahota, Christos Komninakis
  • Patent number: 8170519
    Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.
    Type: Grant
    Filed: December 9, 2010
    Date of Patent: May 1, 2012
    Assignee: American Radio LLC
    Inventor: Robert Hotto
  • Patent number: 8164496
    Abstract: In a compensator for compensating mismatches, and in methods for such compensation, the compensator compensates for mismatches in output signals of a system with mismatches during normal operation of the system with mismatches. The compensator comprises: a mismatch estimator that monitors at least two mismatched signals output by the system with mismatches during normal operation and that generates matching parameters indicating an amount of mismatch between the at least two mismatched signals, the mismatch estimator updating the matching parameters during normal operation of the system with mismatches, and a mismatch equalizer that compensates mismatches in the mismatched signals output by the system with mismatches during normal operation of the system with mismatches in response to the matching parameters.
    Type: Grant
    Filed: October 20, 2010
    Date of Patent: April 24, 2012
    Inventor: Scott R. Velazquez
  • Patent number: 8160648
    Abstract: Receiver diversity in a wireless device is controlled in response to operating conditions, transmission requirements, and control settings. The control of diversity reduces power consumption by enabling receive diversity on given conditions. Operating conditions, transmission requirements, and control settings are used separately or used in conjunction to determine whether benefits of multi-antenna receive diversity, such as higher link capacity, higher data throughput, lower transmit power, and lower error rate, warrant the higher power cost of the diversity.
    Type: Grant
    Filed: April 28, 2010
    Date of Patent: April 17, 2012
    Assignee: Qualcomm Incorporated
    Inventors: Fatih Ulupinar, Gregory A. Breit, Brian C. Banister, Edward G. Tiedemann, Jr.
  • Patent number: 8140019
    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: March 20, 2012
    Assignee: LG Electronics Inc.
    Inventors: Jae Wan Kim, Wook Bong Lee, Su Nam Kim, Dong Guk Lim, Bin Chul Ihm
  • Patent number: 8139693
    Abstract: An estimation method is provided for use in a receiver of an OFDM (orthogonal frequency division multiplexing) system to estimate the ICI (inter-carrier interference) and the noise power of a channel. Two pilot signals respectively carried by two subcarriers are received from the channel wherein the two pilot signals are adjacent and differ by a first phase angle. Another two pilot signals respectively carried by another two subcarrier are received from the channel wherein the another two pilot signals are adjacent and differ by a second phase angle. According to some embodiments of the invention, these phases are correlated with the ICI power, but are uncorrelated with the noise power. The estimation method then individually estimates the ICI power and noise power according to the first phase and the second phase.
    Type: Grant
    Filed: June 19, 2009
    Date of Patent: March 20, 2012
    Assignee: Industrial Technology Research Institute
    Inventors: Lai-Huei Wang, Pang-An Ting, Chien-Yu Kao, Chia-Hung Lin
  • Patent number: 8135078
    Abstract: A device and method for performing a channel profile estimation for an OFDM-based wireless communication system uses an averaged frequency coherence metric to select a particular channel profile, which is a current channel profile estimate. The averaged frequency coherence metric is derived using correlations between pilot subcarriers of an OFDM-based signal at predefined subcarrier locations for multiple frames of the OFDM-based signal. The selected channel profile may be used for channel estimation, as well as for link adaptation, to improve the performance of these processes.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: March 13, 2012
    Assignee: Amicus Wireless Technology Ltd.
    Inventors: Kee-Bong Song, Won-Joon Choi
  • Patent number: 8130848
    Abstract: A device and method for performing a channel estimation for an OFDM-based wireless communication system using sparsely spaced pilot subcarriers estimates missing pilot subcarriers in an interpolation window using pilot subcarriers that are outside of the interpolation window to produce estimated pilot subcarriers for the interpolation window. The pilot subcarriers in the interpolation window and the estimated pilot subcarrier are used to compute pilot channel estimates for the interpolation window, which are then used to derive data channel estimates for the interpolation window.
    Type: Grant
    Filed: May 1, 2008
    Date of Patent: March 6, 2012
    Assignee: Amicus Wireless Technology Ltd.
    Inventors: Kee-Bong Song, Won-Joon Choi
  • Patent number: 8103235
    Abstract: A phase and amplitude controller reads from a switching control table an antenna switching number and values of I and Q corresponding to a receiving channel number reported from a W-CDMA receiver module, and outputs the antenna switching number and the values of I and Q to a switch and DACs, respectively. After a phase and amplitude adjustment IC adjusts the phase and amplitude of a noise signal obtained through the switch by using the values of I and Q inputted through the DACs, it inverts the phase of the noise signal and adds the resulting signal to a reception signal received by a communication antenna, and consequently the noise component is canceled from the reception signal.
    Type: Grant
    Filed: October 24, 2008
    Date of Patent: January 24, 2012
    Assignee: Fujitsu Limited
    Inventors: Shinichi Shiotsu, Akira Shiba
  • Patent number: 8095092
    Abstract: One embodiment of the present invention relates to a method for transistor matching. The power transmitter comprises a first, second, and third amplification path. The paths are selectively activated and deactivated to output a received signal with high efficiency and linearity. The first amplification path is configured to receive a first signal and output a first amplified signal to a first port of a output power combiner when activated and provide an impedance that results in a high reflection factor when deactivated. The second amplification path is configured to receive a second signal with 90° phase shift with respect to the first signal and output a second amplified signal to a second port of the combiner when activated and provide an impedance that results in a high reflection factor when deactivated.
    Type: Grant
    Filed: June 26, 2008
    Date of Patent: January 10, 2012
    Assignee: Infineon Technologies AG
    Inventors: Jan-Erik Muller, Bernhard Sogl, Wolfgang Thomann
  • Patent number: 8086206
    Abstract: A quadratic amplitude matching system and associated method with an associated tuning control system is provided for continuously and automatically tuning a quadratic amplitude matching filter (QAMF) to a band center of an interfering signal to provide improved rejection of an interfering signal coupled from a transmission antenna into a local receive antenna in the presence of local multi-path, thereby providing improved interference cancellation system performance. The matching control system is provided as an element of an interference cancellation system.
    Type: Grant
    Filed: August 15, 2011
    Date of Patent: December 27, 2011
    Assignee: BAE Systems Information and Electronic Systems Integration Inc.
    Inventor: Raymond J. Lackey
  • Patent number: 8064897
    Abstract: A transmission/reception apparatus capable of preventing degradation in system capacity, improving system throughput, and minimizing power consumption of an apparatus is disclosed. In this apparatus, a propagation path determining section (131) determines a propagation path state in all the regions in the used frequency band of a received multicarrier signal based on propagation path estimation information such as a channel estimation value and the like calculated in a propagation path estimating section (126), and specifies a frequency region having a good propagation path state from the used frequency band of OFDM. More specifically, the used frequency band is divided into a plurality of frequency bands (subbands), each comprised of smaller predetermined bandwidth, and by selecting a subband having a good propagation path state in the propagation path determining section (131), a frequency region having the good propagation path state is specified.
    Type: Grant
    Filed: January 27, 2005
    Date of Patent: November 22, 2011
    Assignee: Panasonic Corporation
    Inventors: Atsushi Matsumoto, Sadaki Futagi, Akihiko Nishio, Daichi Imamura
  • Patent number: 8045942
    Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.
    Type: Grant
    Filed: February 9, 2010
    Date of Patent: October 25, 2011
    Assignee: American Radio LLC
    Inventor: Robert Hotto
  • Patent number: 8041404
    Abstract: A system and method for managing messaging in a mobile communication system (e.g., having power-save capability) in a multiple network environment. For example, the mobile communication system may operate in a power-save mode (e.g., a mode in which the mobile communication system does not communicate messages). The mobile communication system may exit the power-save mode. After exiting from the power-save mode, the mobile communication system may determine to establish communication with a second system (e.g., a message server) over a second communication path instead of a first communication path. Communication with the second system may be established over the second communication path, and message-related information may be communicated between the mobile communication system and the second system. Such message-related information may, for example, comprise message information, information regarding message availability, or information regarding the communication of message information.
    Type: Grant
    Filed: October 28, 2010
    Date of Patent: October 18, 2011
    Inventors: Jeyhan Karaoguz, Nambirajan Seshadri, James D. Bennett
  • Patent number: 7970361
    Abstract: A user equipment (UE) without service in a communication system measures the radio-frequency (RF) power in a bandwidth received by the UE on the possible downlink carriers in a frequency band that is supported by the UE. The bandwidth is typically the bandwidth of communication channels in the communication system. If the UE supports more than one frequency band, the UE may scan more than one of those frequency bands. The UE processes the measurement results with a noise-reducing enhancement technique, such as a median filter, and then examines the processed results for a particular spectral shape, e.g., a shape that corresponds to a cell signal.
    Type: Grant
    Filed: November 28, 2007
    Date of Patent: June 28, 2011
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Ali G. Nader, Béla Rathonyi
  • Patent number: 7941118
    Abstract: A method to process DP bits and TPC bits from multiple fingers within a WCDMA rake receiver is provided. DPCH symbols are received, quantized and channel compensated. Then processing operations for individual fingers for the channel compensated quantized despread DPCH symbols containing DP bits and TPC bits are chosen based on the DPCH slot format. The DPCH symbols are processed based on the DPCH slot format in order to produce processed DPCH pilot symbols in a common format. DP bits and TPC bits may be processed in parallel by separate processing branches or in series by applying timing control to common processing modules. These processed symbols may then be combined. Other embodiments may further allow for the computation of an SNR estimate based on the combined DPCH symbols.
    Type: Grant
    Filed: September 28, 2007
    Date of Patent: May 10, 2011
    Assignee: Broadcom Corporation
    Inventors: Severine Catreux, Ian Riphagen
  • Patent number: 7925302
    Abstract: Receiver diversity in a wireless device is controlled in response to operating conditions, transmission requirements, and control settings. The control of diversity reduces power consumption by enabling receive diversity on given conditions. Operating conditions, transmission requirements, and control settings are used separately or used in conjunction to determine whether benefits of multi-antenna receive diversity, such as higher link capacity, higher data throughput, lower transmit power, and lower error rate, warrant the higher power cost of the diversity.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: April 12, 2011
    Assignee: Qualcomm Incorporated
    Inventors: Fatih Ulupinar, Gregory A. Breit, Brian C. Banister, Edward G. Tiedemann, Jr.
  • Patent number: 7917096
    Abstract: An electronic device includes an antenna, a radio frequency circuit, and an impedance matching circuit that is connected between the antenna and the radio frequency circuit. The impedance matching circuit includes a plurality of impedance matching networks that are respectively associated with frequency bands used by the radio frequency circuit.
    Type: Grant
    Filed: March 30, 2007
    Date of Patent: March 29, 2011
    Assignee: Sony Ericsson Mobile Communications AB
    Inventor: Bruce E. Wilcox
  • Publication number: 20110065408
    Abstract: An interference signal cancellation device comprises a signal splitter, a delay element and a signal combiner. The signal splitter distributes a disturbed signal to a first signal path and a second signal path. The delay element is situated in at least one of the first signal path and the second signal path for introducing a relative delay between a first signal in the first signal path and a second signal in the second signal path. The signal combiner combines the first signal and the second signal. An interference signal within the disturbed signal is substantially reduced within the signal combiner. A method for interference signal cancellation is also proposed. Furthermore, a computer program product with instructions for the manufacture and a computer program product enabling a processor to carry out the method for interference signal cancellation are also proposed.
    Type: Application
    Filed: September 17, 2009
    Publication date: March 17, 2011
    Inventors: Peter Kenington, Dirk Neumann
  • Publication number: 20110002427
    Abstract: A wireless receiver including receiving antennas, frequency-space transformers, noise wave removers, a back-end signal processor, a pattern detector, a broadcast interruption detector, and a back-end controller. The frequency-space transformers convert signals received by the antennas into frequency-space signals. The noise wave removers each at least perform the calculation of a transmission line coefficient matrix and the calculation of an inter-antenna covariance matrix on the frequency-space signals. A controller controls the back-end signal processor to operate when the multicarrier transmission waves have been detected to be interrupted. The noise wave removers each perform the calculation of the inter-antenna covariance matrix when a broadcast interruption detector has detected the interruption of the multicarrier airwaves. Thus, the wireless receiver removes noise generated within it, thereby having high reception sensitivity.
    Type: Application
    Filed: August 4, 2009
    Publication date: January 6, 2011
    Inventor: Yasuo Hamamoto
  • Publication number: 20100309994
    Abstract: The method described herein characterizes scattering objects in a wireless channel. Broadly, the present invention determines non-equally spaced path delays and Doppler parameters for a plurality of scattering objects in a wireless channel. More particularly, a frequency-to-time transform applied to a plurality of OFDM pilot samples received over a plurality of OFDM symbol periods generates a set of non-equally spaced path delays and a set of associated complex delay coefficients. Further, a time-to-frequency transform applied to the complex delay coefficients determined for one path delay over multiple OFDM symbol periods generates a set of Doppler parameters comprising a plurality of non-equally spaced Doppler frequencies and their corresponding scattering coefficients for that path delay.
    Type: Application
    Filed: June 4, 2009
    Publication date: December 9, 2010
    Inventors: Paul Wilkinson Dent, Leonid Krasny
  • Patent number: 7831197
    Abstract: The invention proposes an LNB using two transposition frequencies chosen on either side of the reception band so as to obtain a transposition of supradyne type and a transposition of infradyne type according to the frequency used. This choice of transposition frequencies makes it possible to have an overlap zone in the middle of the reception band which is transposed with the aid of the two oscillation frequencies but at different frequencies. This makes it possible to choose between the two transpositions in the case where the frequency transposed with the aid of an oscillator corresponds to a particularly noisy frequency.
    Type: Grant
    Filed: December 15, 2004
    Date of Patent: November 9, 2010
    Assignee: Thomson Licensing
    Inventor: Marc Louchkoff
  • Patent number: 7831233
    Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.
    Type: Grant
    Filed: December 10, 2007
    Date of Patent: November 9, 2010
    Assignee: American Radio LLC
    Inventor: Robert Hotto