Anti-multipath Patents (Class 455/65)
  • Patent number: 8412126
    Abstract: Methods of forming a downlink beam in an adaptive antenna system of a communications system that may reduce inter-system and/or intra-system interference include receiving vectors of signals including signals transmitted by user terminals of the communications system and signals transmitted by transceivers of an independent communications system, obtaining spatial information for the user terminals of the communications system and the transceivers of the independent communications system, generating complex transmitting weights that form spatial nulls directed at the transceivers of the independent communications system, and transmitting a downlink communications signal using the complex transmitting weights. Related systems are also disclosed.
    Type: Grant
    Filed: April 1, 2010
    Date of Patent: April 2, 2013
    Assignee: ATC Technologies, LLC
    Inventors: Peter D. Karabinis, Dunmin Zheng
  • Patent number: 8412271
    Abstract: A base station includes a reference signal generator, a boost selector, and a transmitter. The reference signal generator provides a dedicated reference signal to be transmitted over a plurality of antennas to a dedicated user device. The boost selector selects a dedicated boost level that is specific for the dedicated reference signal. The boost selector applies the dedicated boost level to the dedicated reference signal and not to a data signal to be transmitted to the dedicated user device. The boost selector generates a boosted dedicated reference signal. The transmitter transmits the boosted dedicated reference signal and the data signal to the dedicated user device after beamforming weights are applied to the boosted dedicated reference signal and to the data signal.
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: April 2, 2013
    Assignee: Marvell World Trade Ltd.
    Inventor: Daniel Yellin
  • Patent number: 8406754
    Abstract: An apparatus and method for beamforming in a wireless communication system are provided. The base station apparatus includes a calculator, a plurality of formers, and a plurality of adders. The calculator calculates a beam coefficient considering interference to a neighbor sector to be applied to transmission signals to mobile stations. The plurality of formers performs beamforming for a transmission signal to each mobile station within a corresponding sector using the beam coefficient. The plurality of adders adds the sector-based beamformed signals each provided from the plurality of formers, on a per-transmission-antenna basis.
    Type: Grant
    Filed: February 27, 2008
    Date of Patent: March 26, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Heon-Ki Chae, Keun-Chul Hwang, Byoung-Ha Yi
  • Patent number: 8401485
    Abstract: A device system, computer medium and method for calibrating at least one impairment of a signal transmitted from a transmitting unit to a receiving unit, the method including receiving at the receiving unit at least two signals transmitted from the transmitting unit, estimating at the receiving unit, based on the received at least two signals, at least one parameter associated with transmit chain links between the transmitting unit and corresponding antennas of the transmitting unit, collecting the at least one parameter in a measurement report at the receiving unit, and transmitting the measurement report from the receiving unit for correcting the at least one impairment based on the at least one parameter.
    Type: Grant
    Filed: February 6, 2008
    Date of Patent: March 19, 2013
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: George Jöngren, David Astely, Bo Göransson, Jonas B. Karlsson
  • Patent number: 8396176
    Abstract: An OFDM receiving device for settling a problem of complicated configuration is provided, in that the OFDM receiving device receives an OFDM signal where no smaller than one specific sub-carriers among plurality of sub-carriers are modulated by a known modulation signal sk(t), and includes a converting means for converting the received OFDM signal into the received signals for each sub-carrier, an extracting means for extracting the ingredient caused by a frequency drift and a phase noise based on received signal rk(t) of the specific sub-carrier and the known modulation signal sk(t), and a compensating means for H) compensating the received signal of the sub-carrier using the extracted ingredient.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: March 12, 2013
    Assignee: NEC Corporation
    Inventor: Masaki Ichihara
  • Patent number: 8396147
    Abstract: A MIMO transmitter and method for transmitting a group of sequential OFDM symbols on a downlink channel using a plurality of antennas is disclosed herein. Groups of OFDM subcarriers are individually modulated in accordance with spatial-frequency subcarrier modulation assignments to generate groups of symbol-modulated subcarriers, corresponding symbol-modulated subcarriers are combined for transmission on each of a plurality of spatial channels, and beamforming is performed on the combined symbol-modulated subcarriers for transmission over the spatial channels. The channel comprises a plurality of the groups of the OFDM subcarriers and the OFDM subcarriers within each group of subcarriers and within each group of sequential OFDM symbols have the same spatial-frequency subcarrier modulation assignments. The spatial-frequency subcarrier modulation assignments for each group are determined based on feedback by a receiver, which is determined from spatial channel characteristics of the spatial channels.
    Type: Grant
    Filed: April 9, 2010
    Date of Patent: March 12, 2013
    Assignee: Intel Corporation
    Inventors: John S. Sadowsky, Minnie Ho, Eric A. Jacobsen, Alexander A. Maltsev, Ali S. Sadri, Sumeet Sandhu
  • Patent number: 8340139
    Abstract: In wireless systems, method and system for weight determination in a single channel (SC) multiple-input multiple-output (MIMO) system for WCDMA/HSDPA are provided. Models of signals received in multiple receive antennas may be determined in a single weight baseband generator (SWBBG) from propagation channel estimates and noise statistics. The models may be utilized to determine combined signal and noise components. The combined signal and noise components may be utilized to determine a plurality of signal-to-noise ratio (SNR) or signal-to-interference-and-noise ratio (SINR) values for various phase and/or amplitude factors. The SINR may be utilized when either single or multiple interfering signals are present. A highest of the SINR or SNR values may be selected to determine a channel weight to apply to the additional receive antennas.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: December 25, 2012
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Vinko Erceg, Uri M. Landau, Pieter G. W. van Rooyen
  • Patent number: 8340606
    Abstract: A transmitter and a signal amplifier are provided. The signal amplifier includes a digital-to-analog converter converting an input digital signal into an analog signal, a local oscillator signal generator outputting in-phase and quadrature-phase oscillator signals, a first mixer mixing the analog signal with the in-phase local oscillator signal to output an in-phase high frequency signal, a second mixer mixing the analog signal with the quadrature-phase local oscillator signal to output a quadrature-phase high frequency signal, a main amplifier amplifying the in-phase high frequency signal output from the first mixer, and an auxiliary amplifier amplifying the quadrature-phase high frequency signal output from the second mixer.
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: December 25, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Jin-soo Park, Do-hyung Kim, Jin-wook Burm, Seong-soo Lee, Heung-bae Lee
  • Publication number: 20120321009
    Abstract: A multiple independent narrow-channel wireless network and method for transmitting and received data over a wireless network using a fragmented frequency spectrum. The system and method uses a plurality of narrow wireless channels obtained from splitting a wide wireless channel. Each narrow channel performs sending, receiving, and carrier sensing. Moreover, each narrow channel is independent such that data can be sent or received without any interference from other narrow channels and without synchronization. Embodiments of the system and method include a compound radio having a compound receiver and a compound transmitter. The compound transmitter includes an inter-radiolet symbol synchronization module, to permit use of a single inverse fast Fourier transform block, and a dynamically configurable filter array, to mitigate leakage between channels. The compound receiver uses fraction data rate processing to optimize efficiency.
    Type: Application
    Filed: June 17, 2011
    Publication date: December 20, 2012
    Applicant: Microsoft Corporation
    Inventors: Krishna Kant Chintalapudi, Bozidar Radunovic, Horia Vlad Balan, Michael Buettner, Vishnu Navda, Ramachandran Ramjee
  • Patent number: 8315321
    Abstract: A method and mobile communication station for communicating orthogonal frequency division multiplexed (OFDM) symbols uses two or more antennas. The antenna parameters are set for beamforming, a transmit power level is initially set, and subcarrier modulation assignments are selected after the antenna parameters and the transmit power level are set to achieve a quality-of-service level for a particular application and data type of a service flow. The transmit power level may also be set based on a desired cell size.
    Type: Grant
    Filed: December 21, 2009
    Date of Patent: November 20, 2012
    Assignee: Intel Corporation
    Inventors: Eric A. Jacobsen, Adrian P Stephens
  • Publication number: 20120244897
    Abstract: Embodiments of the present invention disclose an interference elimination method and apparatus for a multi-antenna system. The method includes: generating an equalization coefficient according to a baseband signal received on a receiving antenna, a channel estimation matrix, and an obtained cross-correlation matrix of transmitted signals of a downlink channel on multiple transmit antennas; and performing interference elimination processing on the baseband signal according to the equalization coefficient.
    Type: Application
    Filed: March 23, 2012
    Publication date: September 27, 2012
    Applicant: Huawei Technologies Co., Ltd.
    Inventors: Yi Yang, Shuojun Yu, Gengshi Wu, Nian Peng, Feng Li
  • Patent number: 8219053
    Abstract: A system and method of automatically tuning a reading device that remotely monitors RFID tags or transponders. The reading device utilizes the phase signal of an antenna signal wherein the harmonic of the antenna signal is filtered through a signal coupling transformer and utilizes the antenna current reading to determine the optimal capacitance setting for the reader by adjusting capacitors and storing the relative phase signal and level of current in a processor. In one embodiment, the method comprises supplying power to the reading device, monitoring the power supply, storing data related to the monitored power supply, emitting a signal from an antenna, filtering the harmonic of such signal, outputting the phase signal to a processor and adjusting capacitors based on the phase signal and monitored current.
    Type: Grant
    Filed: October 20, 2008
    Date of Patent: July 10, 2012
    Assignee: Destron Fearing Corporation
    Inventors: Ezequiel Mejia, Yuri Smirnov
  • Patent number: 8208855
    Abstract: Provided is a method for transitioning between a distributed transmission mode and a localized transmission mode, including transmitting, by a Base Station (BS), a measurement control message to a User Element (UE), wherein the UE makes corresponding measurement and transmits a required measurement report message to the BS and the BS transmits a transition indicator message of new mode to the UE based on measurement report message sent from the UE; and commencing CQI reporting and a downlink transmission of a new mode between the UE and the BS. The BS can choose a more appropriate transmission mode for the downlink transmission based on changing characteristics of the channel in the time domain and the frequency domain.
    Type: Grant
    Filed: January 8, 2007
    Date of Patent: June 26, 2012
    Assignees: Samsung Electronics Co., Ltd, Beijing Samsung Telecom R&D Center
    Inventors: Ju-Ho Lee, Xiaoqiang Li, Chengjun Sun, Chunying Sun, Yujian Zhang
  • Patent number: 8208587
    Abstract: In a geolocation application, a method is provided to jointly estimate the time-of-arrival (TOA) and the amplitude of a received signal based on super-resolution technique. The super-resolution joint TOA-amplitude estimators are provided based on either the expectation-maximization (EM), parallel-interference-cancellation space-alternating generalized expectation maximization (PIC-SAGE) or serial-interference-cancellation SAGE (SIC-SAGE). The SIC-SAGE estimator minimizes the ranging estimation error especially under a non-line-of-sight (NLOS) condition. The SIC-SAGE estimator is a simplified version of the maximum likelihood estimator with more stable performance in a multipath rich environment, such as the ultra-wideband (UWB) based applications. These techniques provide the following benefits: 1) it is generic, so that signal processing can be deployed on both time-domain (e.g., UWB impulse-radio) and frequency-domain (e.g.
    Type: Grant
    Filed: April 18, 2008
    Date of Patent: June 26, 2012
    Assignee: NTT DoCoMo, Inc.
    Inventors: Chia-Chin Chong, Fujio Watanabe, Hiroshi Inamura
  • Patent number: 8185064
    Abstract: Object To reduce deterioration of transmission quality under circumstances where the moving speed is high. Overcoming Means An adaptive modulation control apparatus for adaptively selecting a modulation parameter from among a plurality of modulation parameters determined based on a plurality of modulation schemes, coding rates of error correction or a combination thereof corresponding to a propagation path state is provided with a reception state measuring section (2) that measures a reception state of a signal received from a communicating apparatus, a correcting section (3) that makes a correction to change propagation path information indicative of a measurement result of the propagation path state based on the measured reception state, and a modulation parameter selecting section (4) that selects a modulation parameter corresponding to the corrected propagation path information.
    Type: Grant
    Filed: February 14, 2006
    Date of Patent: May 22, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshizo Nogami, Takashi Onodera, Hidekazu Tsuboi
  • Patent number: 8179251
    Abstract: A wireless sensor network includes an initial set of anchors at known locations, and a set of sensors at unknown locations. Ranges, from each sensor to at least three of the anchors, determine a position, an anchor ranging weight, and an anchor position weight. For each anchor, the anchor ranging weight and the anchor position weight form a combined weight. A weighted least square (WLS) function for the positions and the combined weights is minimized to determine a position of the sensor, and a sensor position weight. The sensor is identified as being a member of a set of candidate anchor nodes, and the candidate anchor node with a largest sensor position weight is selected to be transformed to another anchor to minimize propagation of errors in the positions of the set of sensors.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: May 15, 2012
    Assignee: Mitsubishi Electric Research Laboratories, Inc.
    Inventors: Nayef Alsindi, Chunjie Duan, Jinyun Zhang
  • Patent number: 8155244
    Abstract: A receiver and a method to demodulate an unknown signal with an unknown linear modulation is described. The method of one of various embodiments comprises: sampling the unknown signal at a sampling rate to produce a sampled signal; applying carrier frequency offset estimation to the sampled signal to match the frequency of the sampled signal to that of the unknown signal and to change constellation rotation of the sampled signal; utilizing symbol period estimation to match the sampling rate of the sampled signal to a sampling rate of the unknown signal; applying blind equalization to the sampled signal to provide an equalized unknown signal; and demodulating the equalized unknown signal by utilizing a multistep windowed histogram clustering algorithm to generate constellation clusters; applying a rotation rate estimation algorithm to the clusters to estimate a phase rotation rate; and utilizing the phase rotation rate estimate to de-rotate the clusters.
    Type: Grant
    Filed: July 8, 2008
    Date of Patent: April 10, 2012
    Assignee: The Boeing Company
    Inventor: Gary Alan Ray
  • Patent number: 8150315
    Abstract: A method for verifying alignment between first and second integrated devices coupled together using a reference and a coupling capacitor, including: transmitting a reference signal on a transmission electrode of the reference capacitor; receiving a coupling signal on a reception electrode of the reference capacitor; amplifying the coupling signal, generating a reception reference signal; generating a reception control signal as a function of the reception reference signal; transmitting a communication signal on an electrode of the coupling capacitor; receiving a reception signal on an electrode of the coupling capacitor; amplifying the reception signal, generating a first compensated signal; controlling a level of amplification of amplifying the coupling signal and the reception signal as a function of the reception control signal; and detecting a possible misalignment between the first and second devices based on an amplitude of the communication signal and an amplitude of the compensated signal.
    Type: Grant
    Filed: June 29, 2010
    Date of Patent: April 3, 2012
    Assignee: STMicroelectronics S.r.l.
    Inventors: Roberto Canegallo, Mauro Scandiuzzo, Eleonora Franchi Scarselli, Antonio Gnudi, Roberto Guerrieri
  • Patent number: 8140037
    Abstract: A wireless transmission apparatus that can accurately select an optimal modulation scheme on a per block basis in a multi-carrier communication system in which block division of subcarriers and adaptive modulation are performed. In this wireless transmission apparatus, a propagation path characteristics acquisition section acquires the average SNR and SNR variance for each block, which are estimated by a wireless reception apparatus, using received signals inputted from a reception RF section and outputs these to an assignment section. The assignment section selects a modulation scheme for each block based on the average SNR and SNR variance of each block inputted from the propagation path characteristics acquisition section and modulation sections modulate multi-carrier signals included in each block, with the modulation scheme for each block selected by the assignment section.
    Type: Grant
    Filed: November 2, 2010
    Date of Patent: March 20, 2012
    Assignee: Panasonic Corporation
    Inventors: Jun Cheng, Kenichi Miyoshi
  • Patent number: 8135351
    Abstract: A method for improving channel estimation in a wireless communication system is disclosed. A wireless signal that includes a plurality of multipath components is received. N channel estimates are then obtained, where N is any positive integer greater than one. Each channel estimate of the N channel estimates corresponds to a different multipath component of the plurality of multipath components. The effects of interference between the plurality of multipath components on the N channel estimates is then reduced.
    Type: Grant
    Filed: May 2, 2007
    Date of Patent: March 13, 2012
    Assignee: Qualcomm Incorporated
    Inventors: Durga Prasad Malladi, Josef Blanz, Yongbin Wei
  • Patent number: 8126490
    Abstract: A radio receiver (FM radio receiver) has an amplitude detecting section (13) for detecting the amplitude level of a received radio wave; a multipath occurrence state detecting section (14) for monitoring the amplitude level, and for detecting the degree of a multipath occurrence state; a multipath occurrence state deciding section (15) for deciding the operation limiting level of the amplitude correction according to the degree of the multipath occurrence state; a receiving condition deciding section (20) for deciding receiving conditions of the radio wave; and a limiting level deciding section (21) for adjusting the operation limiting level of the amplitude correction output from the multipath occurrence state deciding section (15) according to a receiving condition decision result output from the receiving condition deciding section (20), and suppresses the multipath noise by imposing operation limitations on the amplitude correction of the FM demodulator 9.
    Type: Grant
    Filed: January 20, 2009
    Date of Patent: February 28, 2012
    Assignee: Mitsubishi Electric Corporation
    Inventors: Kenichi Taura, Yuji Matsuda
  • Patent number: 8126489
    Abstract: In an RF communication system, aspects for diversity processing may comprise processing a plurality of received multipath signals as clusters of signals. The received multipath signals may be diversity signals received from diversity transmit antennas at a base station. Timing information may be generated for tracking the clusters of signals. Complex phase and amplitude information may also be estimated for at least some of the multipath signals in the clusters of signals. At least a portion of the received multipath signals may be combined to form a single path processed diversity signal. A plurality of the single path processed diversity signals may be combined together, where each of the single path processed diversity signals may be derived from one of the plurality of diversity transmit antennas at the base station. The diversity signals may be transmitted via at least one of a plurality of diversity modes.
    Type: Grant
    Filed: January 5, 2010
    Date of Patent: February 28, 2012
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Vinko Erceg, Uri Landau
  • Patent number: 8126405
    Abstract: A method measures a time from transmitting a ranging signal to receiving the ranging signal via a channel of a wireless network, and a received signal strength (RSS) of the ranging signal. A distance is estimated based on the time, and a path loss based on the RSS. Probabilities of conditions of the channel are estimated based on the distance and the path loss, wherein the condition is in one of line-of-sight (LOS), or non-LOS (NLOS).
    Type: Grant
    Filed: February 10, 2009
    Date of Patent: February 28, 2012
    Assignee: Mitsubishi Electric Research Laboratory, Inc.
    Inventors: Chunjie Duan, Nayef Alsindi, Jinyun Zhang
  • Patent number: 8116795
    Abstract: It is an object of the present invention to hold the detecting range of a timing correlator in a base station to the minimum required and to reduce the circuit scale and power requirement of the timing correlator. Before a mobile station transmits a data signal, it transmits a signal referred to as a preamble signal to measure the transmission timing to the base station. If the base station detects the preamble signal with a timing correlator having a limited circuit scale, then the base station transmits a transmission permission signal to the mobile station. If the mobile station fails to receive the transmission permission signal over a given period of time after it has transmitted the preamble signal, then the mobile station retransmits the preamble signal at a changed transmission timing based on the received electric power of a control signal transmitted continuously from the base station and information included in the control signal.
    Type: Grant
    Filed: February 19, 2007
    Date of Patent: February 14, 2012
    Assignee: NEC Corporation
    Inventor: Suguru Nakada
  • Patent number: 8090563
    Abstract: A method for simulating a telecommunications network through objects that model a respective set of network modules or devices provides for the insertion, for every module or device of the set, of at least one respective interfacing object with the other modules of the set. The above interfacing object has an external side and an internal side with respect to the module or device. Such external side has a character that is independent of idiosyncrasies of such module or device and is therefore uniform for all modules or devices. When there are a plurality of different implementations of the same module or device, it is possible to provide both a unique interfacing object for all different implementations, and a respective interfacing object for every single implementation.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: January 3, 2012
    Assignee: Telecom Italia S.p.A.
    Inventors: Andrea Barbaresi, Paolo Goria, Saverio Nannicini
  • Patent number: 8077796
    Abstract: Systems and methods for utilizing new communication standards in wireless local area networks are provided that also support legacy wireless stations. The method can include user equipment determining channel state information, selecting a unitary channel decomposition precoder format based on the determined channel state information and transmitting the precoder format information to a base station. During a return transmission the user equipment can receive user data with the precoder format information and utilize a non-linear detector to demodulate and decode the user data. Based on the reception the user equipment can estimate channel quality; and transmitting channel quality information as feedback.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: December 13, 2011
    Assignee: Intel Corporation
    Inventors: Xiao-Feng Qi, Keith Holt
  • Patent number: 8073064
    Abstract: Identifying a trigger point of at least one OFDM decoder includes correlating a first time-domain sample of the at least one OFDM symbol with a second time-domain sample of the at least one OFDM symbol, processing the first time-domain sample and the second time-domain sample in the first moving average filter to determine a channel impulse response, comparing at least one correlation value of a first biggest path in the channel impulse response and a second biggest path in the channel impulse response, and determining a channel length of the channel impulse response based on a time duration of the channel impulse response. The OFDM decoder includes a first moving average filter and a second moving average filter.
    Type: Grant
    Filed: April 18, 2008
    Date of Patent: December 6, 2011
    Assignee: Newport Media, Inc.
    Inventors: Yongru Gu, Jun Ma
  • Patent number: 8064836
    Abstract: In accordance with the present invention, a system and method that exploits the efficiency of the spectrum utilization is provided. The proposed technique, which is referred to as dispersed spectrum utilization, is based on the idea of transmitting the information over multiple dispersed bands in contrast to the current wireless communication systems which transmit the signal over a single band. A cognitive radio transceiver is developed for the implementation of this dispersed spectrum utilization technique.
    Type: Grant
    Filed: April 13, 2009
    Date of Patent: November 22, 2011
    Assignee: University of South Florida
    Inventors: Hasari Celebi, Huseyin Arslan
  • Patent number: 8055289
    Abstract: A signal processing circuit includes a demodulator to demodulate a received signal and output a demodulated signal, a filter to output a signal corresponding to a prescribed frequency component of the demodulated signal, a blending unit to blend the demodulated signal with an output signal of the filter at a prescribed blending ratio, an electric field strength change amount detection unit to detect a change in electric field strength and output an electric field strength change amount, and a blending ratio determination unit to determine the prescribed blending ratio according to the electric field strength change amount.
    Type: Grant
    Filed: July 6, 2007
    Date of Patent: November 8, 2011
    Assignee: Renesas Electronics Corporation
    Inventor: Eiji Sudou
  • Patent number: 8045945
    Abstract: A reception apparatus including an extraction section; a transmission line characteristic estimation section; an interpolation section; a compensation section; a detection section; and a selection section.
    Type: Grant
    Filed: February 26, 2009
    Date of Patent: October 25, 2011
    Assignee: Sony Corporation
    Inventors: Hidetoshi Kawauchi, Tadaaki Yuba, Toshiyuki Miyauchi, Takashi Yokokawa, Takuya Okamoto, Tamotsu Ikeda, Koji Naniwada, Kazuhiro Shimizu, Lachlan Bruce Michael
  • Patent number: 8019010
    Abstract: An orthogonal-frequency division multiplexed (OFDM) transmitter is configured to transmit a data unit in accordance with a multiple-input multiple-output (MIMO) technique over a wideband channel comprising a 20 MHz channel and another channel using a plurality of spatially diverse antennas. The transmitter is further configured to include in the data unit, a parameter indicating a modulation and coding scheme and a parameter indicating number of spatial streams. Each of the spatial streams is encoded and beamformed for receipt by one or more different receiving stations.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: September 13, 2011
    Assignee: Intel Corporation
    Inventors: John S. Sadowsky, Minnie Ho, Sumeet Sandhu, Alexander A. Maltsev, Eric A. Jacobsen, Ali S Sadri
  • Patent number: 7991360
    Abstract: A receiving apparatus, a receiving method, and a radio communications system are disclosed. The receiving apparatus is for receiving CDMA signals transmitted by M antennas and received by N antennas, where M and N are positive integers. The receiving apparatus includes a multipath receiving signal demodulating unit for primary demodulation of the CDMA signals received by the receiving antennas to obtain estimated transmission signals, and for obtaining signals in a multipath environment of each path of the receiving antennas based on the estimated results. Further, the receiving apparatus includes a multipath interference canceling unit for deducting signals of the paths other than a target path from the signals received by the receiving antennas to obtain multipath interference cancelled signals. Further, the receiving apparatus includes a demodulator for secondary demodulation of the multipath interference cancelled signals.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: August 2, 2011
    Assignees: NTT DoCoMo, Inc., NEC Corporation
    Inventors: Junichiro Kawamoto, Noriyuki Maeda, Kenichi Higuchi, Mamoru Sawahashi, Shousei Yoshida, Masayuki Kimata
  • Patent number: 7983669
    Abstract: A method is provided for verifying plotting results when multiple signals of the same frequency have been detected from different directions. Signal characteristics of the signals detected from different directions are compared so that, on the basis of the signal comparison, a decision may be made as to whether a reflection from the same transmitter is occurring, or different transmitters are involved.
    Type: Grant
    Filed: December 8, 2006
    Date of Patent: July 19, 2011
    Assignee: EADS Deutschland GmbH
    Inventors: Thomas Kottke, Norbert Jung, Siegfried Kienle
  • Patent number: 7970355
    Abstract: The present invention describes a method of closed loop MIMO communication utilizing implicit or explicit channel state information (CSI) at the transmitter and the receiver. The transmitter performs linear pre-processing (for example, QR decomposition or bi-diagonal decomposition or Jacobi rotations, and/or sporadic SVDs) on a channel matrix, and the receiver mitigates the mutual interference between the streams by performing MMSE processing on the received signals. The MMSE matrix is computed with respect to the processed channel that may estimated by the receiver through preprocessed pilot signals. The transmitters preprocessing is of much lesser cost and complexity than full SVD.
    Type: Grant
    Filed: December 4, 2007
    Date of Patent: June 28, 2011
    Assignee: Designart Networks Ltd
    Inventors: Oz Barak, Assaf Touboul, Avner Dor
  • Patent number: 7961589
    Abstract: A system and related methods for introducing intra-channel spatial diversity within a multi-carrier wideband communication channel is presented. In accordance with one aspect of the present invention, developed more fully below, a method is presented comprising receiving information for transmission to a receiver, and generating a plurality of sub-carriers to redundantly transmit the information to a user over a multi-carrier wireless communication channel, wherein each of the sub-carriers is dynamically modified by a set of complex weights to ensure that each of the sub-carriers of the wireless communication channel propagates along a different physical path to the receiver.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: June 14, 2011
    Assignee: Intel Corporation
    Inventor: Athanasios A. Kasapi
  • Patent number: 7940850
    Abstract: In applications where data is transmitted in frames of symbols and the transmission medium is such that the probability of correct reception of symbols is, on the average, not uniform for different symbols in a frame, transmission of test frames enables creation of information about the different probabilities of correct reception, and that information is employed by the transmitter to control the manner in which symbols are transmitted so as to ameliorate the effects of the different probabilities of correct reception.
    Type: Grant
    Filed: May 9, 2008
    Date of Patent: May 10, 2011
    Inventors: Lusheng Ji, Samrat Bhattacharjee, Bo Han, Seungjoon Lee, Robert Miller
  • Patent number: 7937041
    Abstract: A shared frequency transmitter for use in a network environment where transmitters and receivers of plural radio communication systems in which the same frequency is used exist is disclosed. The shared frequency transmitter includes (a) a communicating unit configured to detect peripheral transmitters existing in a peripheral area, and to exchange information with the detected peripheral transmitters; and (b) a signal generating unit configured to generate a transmit signal by applying an interference cancellation technique based on the information obtained through the exchange of information.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: May 3, 2011
    Assignee: NTT DoCoMo, Inc.
    Inventors: Tetsushi Abe, Hui Shi, Takahiro Asai, Hitoshi Yoshino
  • Patent number: 7929499
    Abstract: In a method of multipath acquisition for a dedicated traffic channel, path positions of the traffic channel that have desired signal energy for processing in a base station receiver may be determined as a function of information contained in a data part and a control part of the traffic channel.
    Type: Grant
    Filed: July 13, 2005
    Date of Patent: April 19, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Francis Dominique, Hongwei Kong
  • Patent number: 7907961
    Abstract: Method and apparatus for improving a noise power estimate in a wideband CDMA (WCDMA) network are disclosed and may include calculating a total noise power estimate for a downlink channel based on a plurality of control channel bits from a plurality of different types of control channels. The plurality of control channel bits may include at least two of: dedicated physical channel (DPCH) transmit power control (TPC) bits, DPCH pilot bits, and common pilot channel (CPICH) bits. A first noise power estimate may be calculated for the downlink channel based on a plurality of the DPCH TPC bits. A value of at least one of the plurality of DPCH TPC bits may not be known when the at least one of the plurality of DPCH TPC bits is received.
    Type: Grant
    Filed: June 7, 2006
    Date of Patent: March 15, 2011
    Inventors: Severine Catreux-Erceg, Vinko Erceg, Mark Kent, Uri M. Landau
  • Patent number: 7885619
    Abstract: Diversity radio transmission is accomplished with excellent performance using multiple antennas receiving a transmission signal from a single power amplifier. A data signal to be transmitted is provided to a first antenna, and a phase-shifted version of the data signal is applied a second antenna. The relative phase shift between the data signal transmitted over the two transmit antennas ensures the two antenna signals can be constructively combined at the receiver. In one non-limiting example embodiment, the relative phase shift is determined by processing pilot signals sent along with the data signal and which are transmitted with predetermined phase shifts.
    Type: Grant
    Filed: June 12, 2007
    Date of Patent: February 8, 2011
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Jung-Fu Cheng, Leonid Krasny, Rajaram Ramesh
  • Patent number: 7885346
    Abstract: A multiple-input-multiple output (MIMO) transmitter for transmitting a group of sequential orthogonal frequency division multiplexed (OFDM) symbols on a time-division duplexed (TDD) channel in accordance with an IEEE 802.16 standard using a plurality of antennas. The MIMO transmitter comprises a spatial-frequency parser to parse a block of bits into spatial-frequency blocks of a variable number of coded bits, and subcarrier modulators to individually modulate OFDM subcarriers with the spatial-frequency blocks in accordance with spatial-frequency subcarrier modulation assignments to generate groups of symbol-modulated subcarriers. The TDD channel comprises a plurality of the groups of the OFDM subcarriers, and the OFDM subcarriers within each group of subcarriers and within each group of sequential OFDM symbols have the same spatial-frequency subcarrier modulation assignments.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: February 8, 2011
    Assignee: Intel Corporation
    Inventors: John S. Sadowsky, Minnie Ho, Sumeet Sandhu, Alexander A. Maltsev, Eric A. Jacobsen, Ali S Sadri
  • Patent number: 7869760
    Abstract: A radio communication device capable of lightening the influence of a frequency selective fading in the wide-band transmission of a single carrier thereby to prevent deterioration of error rate characteristics. In this device, an FFT unit (13) subjects a modulated signal inputted from a modulation unit (12) to a Fourier transformation. A pilot insertion unit (14) inserts a pilot symbol into a plurality of individual frequency components (1-N) of the modulated signal. Weight multiplication units (15-1, 15-2) multiply the individual frequency components (1-N) and the pilot symbols inserted into the individual frequency components (1-N), by weight coefficients (W11-W1N, W21-W2N) set at a weight coefficient setting unit (54). IFFT units (16-1, 16-2) subject the frequency components (1-N) to an inverse Fourier transformation, thereby to convert the frequency components (1-N) into time domains.
    Type: Grant
    Filed: July 12, 2005
    Date of Patent: January 11, 2011
    Assignee: Panasonic Corporation
    Inventor: Akihiko Nishio
  • Patent number: 7869537
    Abstract: A system and method for generating transmit weighting values for signal weighting that may be used in various transmitter and receiver structures is disclosed herein. The weighting values are determined as a function of frequency based upon a state of a communication channel and the transmission mode of the signal. In variations, weighting of the weighted signal that is transmitted through each of a plurality of antennas is carried out with one of a corresponding plurality of transmit antenna spatial weights. In these variations, a search may be conducted over various combinations of transmit weighting values and transmit antenna spatial weights in order to find a weight combination that optimizes a performance measure such as the output signal-to -noise ratio, the output bit error rate or the output packet error rate.
    Type: Grant
    Filed: May 19, 2009
    Date of Patent: January 11, 2011
    Inventors: Severine Catreux, Vinko Erceg, Pieter Roux, Pieter van Rooyen, Jack Winters
  • Patent number: 7860199
    Abstract: Aspects of a method and system for a single antenna receiver system for HSDPA are provided. Aspects of a method for processing RF signals, the method may comprise computing channel estimates based on a plurality of received individual distinct path signals, generating timing reference signals indicating a location of at least one of the plurality of received individual distinct path signals, combining at least a portion of the plurality of received individual distinct path signals as a signal cluster based on at least one of the computed channel estimates and said generated timing reference signals, and selecting at least one of combining and equalization processing based on at least one of the computed channel estimates and the generated timing reference signals. Aspects of a system for processing RF signals may comprise circuitry that selects at least one of combining and equalization processing based the computed channel estimates and/or generated timing reference signals.
    Type: Grant
    Filed: March 16, 2009
    Date of Patent: December 28, 2010
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Vinko Erceg, Uri M. Landau, Pieter van Rooyen
  • Publication number: 20100323625
    Abstract: A base station device (10) communicates between a first terminal device and a second terminal device over the same channel by spatial multiplexing. The base station device (10) comprises an interference cancellation coefficient extractor (30) that extracts an interference cancellation coefficient from a signal received from the first terminal device to cancel interference on a propagation channel with the first terminal device in advance, and transmits a pilot signal that contains information related to the interference cancellation coefficient to the second terminal device.
    Type: Application
    Filed: February 5, 2009
    Publication date: December 23, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Takaaki Kishigami, Shozo Okasaka
  • Patent number: 7853214
    Abstract: In one embodiment of the present invention, a dynamic multi-path detection device is disclosed to include at least one narrow-band signal metric estimator responsive to input signal. Each of the at least one estimators measures a particular characteristic of the input signal in a frequency band that is narrower than the overall signal bandwidth and is operative to generate a signal parameter estimate signal. The dynamic multi-path detection device is further disclosed to include a signal metric comparison device responsive to the signal parameter estimate signal(s) and operative to generate a dynamic multi-path indication signal for detecting dynamic multi-path.
    Type: Grant
    Filed: January 5, 2007
    Date of Patent: December 14, 2010
    Assignee: Microtune (Texas), L.P.
    Inventors: Ping Dong, Jordan Christopher Cookman
  • Patent number: 7848722
    Abstract: A wireless transmission apparatus that can accurately select an optimal modulation scheme on a per block basis in a multi-carrier communication system in which block division of subcarriers and adaptive modulation are performed. In this wireless transmission apparatus, a propagation path characteristics acquisition section acquires the average SNR and SNR variance for each block, which are estimated by a wireless reception apparatus, using received signals inputted from a reception RF section and outputs these to an assignment section. The assignment section selects a modulation scheme for each block based on the average SNR and SNR variance of each block inputted from the propagation path characteristics acquisition section and modulation sections modulate multi-carrier signals included in each block, with the modulation scheme for each block selected by the assignment section.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: December 7, 2010
    Assignee: Panasonic Corporation
    Inventors: Jun Cheng, Kenichi Miyoshi
  • Publication number: 20100298015
    Abstract: The present invention relates to a method of improving the performance of a mobile radio communications system comprising at least one stationary radio transmitter for communicating with user equipments in the communications system, wherein the radio transmitter is connected to an antenna system for which the antenna pattern can be varied, the method comprising: receiving direction-of-propagation information relating to a plurality of user equipment transmission samples, wherein a user equipment transmission sample includes information relating to at least one direction of propagation by which successful communication between a user equipment and the radio transmitter has been established at a particular point in time; selecting (303), based on the direction-of-propagation information, active directions for the communication of common channels from the radio transceiver; and adjusting (305) the antenna pattern used for communication of common channels in accordance with the selected active directions in a man
    Type: Application
    Filed: June 6, 2007
    Publication date: November 25, 2010
    Inventors: Jonas Medbo, Mathias Riback, Jan-Erik Berg
  • Patent number: 7822135
    Abstract: A multiple-input-multiple output (MIMO) transmitter for transmitting an orthogonal frequency division multiplexed (OFDM) symbol over a plurality of spatial channels using a plurality of antennas is described. The transmitter includes encoding circuitry to encode blocks of input bits in accordance with a variable encoding rate to generate blocks of encoded bits and a spatial-frequency parser to parse the blocks of encoded bits into spatial-frequency groups. The transmitter also includes subcarrier modulators to modulate each spatial-frequency group of encoded bits on one of the OFDM subcarriers to generate symbol-modulated subcarriers. Spatial-frequency groups having a greater number of encoded bits are modulated at higher-order modulation levels and spatial-frequency groups having a lesser number of encoded bits are modulated at lower-order modulation orders.
    Type: Grant
    Filed: June 11, 2009
    Date of Patent: October 26, 2010
    Assignee: Intel Corporation
    Inventors: John S. Sadowsky, Minnie Ho, Sumeet Sandhu, Alexander A. Maltsev, Eric A. Jacobsen, Ali S Sadri
  • Patent number: 7822101
    Abstract: According to methods and apparatus taught herein, a parametric model of received signal impairment correlations includes a parametric model term that accounts for a dominant receiver but does not result in any significant increase in parametric modeling complexity. In more detail, the parametric model models the dominant interferer as a spatial interferer, which is hypothesized as a point source of interference emanating along single-path channels to each of two or more receiver antennas. The dominant interferer thus is represented in terms of its spatial correlation across receiver antennas. The dominant interferer model term may be included in an overall model fitting process, or it may be fitted separately. Regardless, the spatial modeling approach taught herein may be used for WCDMA and other systems, and may be embodied in essentially any type of linear equalizer receiver structure.
    Type: Grant
    Filed: June 25, 2007
    Date of Patent: October 26, 2010
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventor: Andres Reial