Patents by Inventor Kazuyoshi Uesaka

Kazuyoshi Uesaka has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8976840
    Abstract: The method disclosed herein is implemented in a radio receiver to detect an AWGN channel, where the radio receiver comprises a rake receiver. The radio receiver receives signals transmitted via a propagation channel from a transmitter, and determines that the propagation channel is an AWGN channel when a filtered version of a minimum value of a metric is lower than a threshold value. The metric relates to a difference between a normalized measured power profile of the propagation channel and a normalized power template, which normalized power template is dependent on predetermined sampling timing shifts and on rake finger positions within the rake receiver.
    Type: Grant
    Filed: May 30, 2014
    Date of Patent: March 10, 2015
    Assignee: ST-Ericsson SA
    Inventors: Kazuyoshi Uesaka, Elias Jonsson, Hisashi Onozawa
  • Publication number: 20140355654
    Abstract: The method disclosed herein is implemented in a radio receiver to detect an AWGN channel, where the radio receiver comprises a rake receiver. The radio receiver receives signals transmitted via a propagation channel from a transmitter, and determines that the propagation channel is an AWGN channel when a filtered version of a minimum value of a metric is lower than a threshold value. The metric relates to a difference between a normalized measured power profile of the propagation channel and a normalized power template, which normalized power template is dependent on predetermined sampling timing shifts and on rake finger positions within the rake receiver.
    Type: Application
    Filed: May 30, 2014
    Publication date: December 4, 2014
    Applicant: ST-Ericsson SA
    Inventors: Kazuyoshi Uesaka, Elias Jonsson, Hisashi Onozawa
  • Patent number: 8848762
    Abstract: This disclosure is directed to a wireless receiver and a method for configuring the wireless receiver, comprising the actions of determining a geometry factor for a channel over which signals are transmitted to the wireless receiver, the geometry factor being a measure indicative of inter-cell interference plus noise power at the wireless receiver; determining the variance of the determined geometry factor, the variance being a measure indicative of the variation in time or rate of the geometry factor; and configuring the wireless receiver based on the geometry factor and the variance of the geometry factor.
    Type: Grant
    Filed: February 4, 2011
    Date of Patent: September 30, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Elias Jonsson, Eric Blanquer, Kazuyoshi Uesaka
  • Patent number: 8837556
    Abstract: In one aspect, the present invention provides for blindly detecting the presence of one or more secondary pilot signals that are not being used to serve a communication apparatus, such as a User Equipment (UE). Among its several advantages, the approach to blind detection taught herein provides robust detection performance, yet it requires relatively few receiver resources. The contemplated apparatus, in at least one example embodiment, uses its blind detection of secondary pilot signal(s) to trigger suppression of secondary pilot interference, for improved reception performance. In a particular, non-limiting example, the apparatus operates in an HSDPA-MIMO network in a non-MIMO mode and blindly detects secondary pilot signal energy associated with the supporting network providing MIMO service to nearby equipment.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: September 16, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (Publ)
    Inventors: Elias Jonsson, Kazuyoshi Uesaka
  • Patent number: 8699546
    Abstract: Techniques are disclosed for determining which channelization codes are used for an interfering HS-PDSCH transmission without knowing whether a neighboring UE targeted by that transmission has had its 64QAM capability activated by higher layer signaling. The average amplitude is measured for each of several possible groups of channelization codes for each of one or more nearby UEs that might be the targets of interfering HS-PDSCH messages. Testing whether the amplitude is approximately the same across the codes in a possible combination of channelization codes yields a metric value that indicates whether that particular combination of codes is likely to be transmitted to a given UE. A second metric that detects the most likely modulation for possible groups of channelization codes is also calculated. The metrics are combined to determine which combination of channelization codes and modulation scheme is most likely being used for addressing the neighboring UE.
    Type: Grant
    Filed: April 20, 2012
    Date of Patent: April 15, 2014
    Assignee: Telefonaktiebolaget L M Ericsson (publ)
    Inventors: Elias Jonsson, Kazuyoshi Uesaka
  • Patent number: 8582624
    Abstract: A set of channelization codes to be monitored is divided into two groups. The first group includes those codes for which an associated symbol modulation and transmit-diversity scheme is known. In the second group are those codes that are characterized by an unknown symbol modulation or unknown transmit-diversity scheme. The quality of the transmission of each code is then evaluated, using a metric. The metric in turn is used to determine whether the code should be used in estimating the covariance matrix by correlating the RAKE data corresponding to the code (i.e., by computing a correlation matrix for the code) or by first subtracting the channel estimates from the channel samples before correlation (i.e., by computing a covariance matrix for the code). An impairment covariance matrix is computed from the covariance matrices and correlation matrices so computed.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: November 12, 2013
    Assignee: Telefonaktiebolaget LM Ericsson (Publ)
    Inventors: Elias Jonsson, Yoshitaka Murata, Jaroslaw Niewczas, Amit Singh, Kazuyoshi Uesaka
  • Publication number: 20130279547
    Abstract: Techniques are disclosed for determining which channelization codes are used for an interfering HS-PDSCH transmission without knowing whether a neighboring UE targeted by that transmission has had its 64QAM capability activated by higher layer signaling. The average amplitude is measured for each of several possible groups of channelization codes for each of one or more nearby UEs that might be the targets of interfering HS-PDSCH messages. Testing whether the amplitude is approximately the same across the codes in a possible combination of channelization codes yields a metric value that indicates whether that particular combination of codes is likely to be transmitted to a given UE. A second metric that detects the most likely modulation for possible groups of channelization codes is also calculated. The metrics are combined to determine which combination of channelization codes and modulation scheme is most likely being used for addressing the neighboring UE.
    Type: Application
    Filed: April 20, 2012
    Publication date: October 24, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON
    Inventors: Elias Jonsson, Kazuyoshi Uesaka
  • Publication number: 20130279555
    Abstract: In one aspect, the present invention provides for blindly detecting the presence of one or more secondary pilot signals that are not being used to serve a communication apparatus, such as a User Equipment (UE). Among its several advantages, the approach to blind detection taught herein provides robust detection performance, yet it requires relatively few receiver resources. The contemplated apparatus, in at least one example embodiment, uses its blind detection of secondary pilot signal(s) to trigger suppression of secondary pilot interference, for improved reception performance. In a particular, non-limiting example, the apparatus operates in an HSDPA-MIMO network in a non-MIMO mode and blindly detects secondary pilot signal energy associated with the supporting network providing MIMO service to nearby equipment.
    Type: Application
    Filed: April 20, 2012
    Publication date: October 24, 2013
    Applicant: TELEFONAKTIEBOLAGET L M ERICSSON
    Inventors: Elias Jonsson, Kazuyoshi Uesaka
  • Publication number: 20120195211
    Abstract: This disclosure is directed to a wireless receiver and a method for configuring the wireless receiver, comprising the actions of determining a geometry factor for a channel over which signals are transmitted to the wireless receiver, the geometry factor being a measure indicative of inter-cell interference plus noise power at the wireless receiver; determining the variance of the determined geometry factor, the variance being a measure indicative of the variation in time or rate of the geometry factor; and configuring the wireless receiver based on the geometry factor and the variance of the geometry factor.
    Type: Application
    Filed: February 4, 2011
    Publication date: August 2, 2012
    Applicant: Telefonakiebolaget L M Ericsson (publ)
    Inventors: Elias Jonsson, Eric Blanquer, Kazuyoshi Uesaka
  • Publication number: 20120082197
    Abstract: A set of channelization codes to be monitored is divided into two groups. The first group includes those codes for which an associated symbol modulation and transmit-diversity scheme is known. In the second group are those codes that are characterized by an unknown symbol modulation or unknown transmit-diversity scheme. The quality of the transmission of each code is then evaluated, using a metric. The metric in turn is used to determine whether the code should be used in estimating the covariance matrix by correlating the RAKE data corresponding to the code (i.e., by computing a correlation matrix for the code) or by first subtracting the channel estimates from the channel samples before correlation (i.e., by computing a covariance matrix for the code). An impairment covariance matrix is computed from the covariance matrices and correlation matrices so computed.
    Type: Application
    Filed: December 22, 2010
    Publication date: April 5, 2012
    Inventors: Elias Jonsson, Yoshitaka Murata, Jaroslaw Niewczas, Amit Singh, Kazuyoshi Uesaka
  • Patent number: 8041325
    Abstract: A mobile receiver having a multi-mode interference suppression function and a way to estimate its speed utilizes a parametric approach to interference suppression at high speeds, and a nonparametric approach at low speeds. In particular, if the mobile receiver is currently operating in a nonparametric mode and its speed exceeds a first predetermined threshold, the mobile receiver switches to a parametric mode. Conversely, if the mobile receiver is currently in parametric mode and its speed is less than a second predetermined threshold, the mobile receiver switches to nonparametric mode. In one embodiment, the speed may be estimated by a Doppler frequency in the received signal, and the thresholds are Doppler frequencies. In one embodiment, the first and second thresholds are different, creating a hysteresis in the mode switching.
    Type: Grant
    Filed: April 22, 2008
    Date of Patent: October 18, 2011
    Assignee: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Elias Jonsson, Douglas A. Cairns, Kazuyoshi Uesaka, Hiroaki Watabe
  • Publication number: 20100238980
    Abstract: The placement of processing delays may be adjusted to facilitate signal reception. In an example embodiment, a composite signal having multiple signal images corresponding to multiple reception delays is received. A root-mean-square (RMS) delay spread is ascertained for the multiple reception delays that correspond to the multiple signal images of the composite signal. A set of temporal points is produced responsive to the RMS delay spread. Multiple processing delays are placed based on the set of temporal points. In different example implementations, the set of temporal points (e.g., of a grid) may be produced by adjusting a spacing between temporal points, by adjusting a total number of temporal points in the set, or by changing a center location of the set. The spacing and number of points may be adjusted responsive to the RMS delay spread. The center location may be adjusted responsive to at least one calculated delay.
    Type: Application
    Filed: March 23, 2009
    Publication date: September 23, 2010
    Inventors: Douglas A. Cairns, Elias Jonsson, Kazuyoshi Uesaka
  • Publication number: 20090149147
    Abstract: A mobile receiver having a multi-mode interference suppression function and a way to estimate its speed utilizes a parametric approach to interference suppression at high speeds, and a nonparametric approach at low speeds. In particular, if the mobile receiver is currently operating in a nonparametric mode and its speed exceeds a first predetermined threshold, the mobile receiver switches to a parametric mode. Conversely, if the mobile receiver is currently in parametric mode and its speed is less than a second predetermined threshold, the mobile receiver switches to nonparametric mode. In one embodiment, the speed may be estimated by a Doppler frequency in the received signal, and the thresholds are Doppler frequencies. In one embodiment, the first and second thresholds are different, creating a hysteresis in the mode switching.
    Type: Application
    Filed: April 22, 2008
    Publication date: June 11, 2009
    Applicant: Telefonaktiebolaget LM Ericsson (publ)
    Inventors: Elias Jonsson, Douglas A. Cairns, Kazuyoshi Uesaka, Hiroaki Watabe