Patents by Inventor Stefan Geirhofer

Stefan Geirhofer 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: 9137802
    Abstract: Techniques for scheduling UEs are described. In one design, a scheduler (e.g., for a cell) may receive channel direction information (CDI) and channel strength information (CSI) from a plurality of UEs. In one design, the CDI from each UE may include at least one eigenvector, and the CSI from each UE may include at least one singular value corresponding to the at least one eigenvector. The scheduler may schedule at least one UE among the plurality of UEs for data transmission based on the CDI and CSI from the plurality of UEs. The scheduler may select the at least one UE based on a metric related to signal-to-leakage ratio (SLR), or spectral efficiency, etc. In one design, the scheduler may evaluate the performance of different sets of UEs to determine whether to schedule one UE for single-user MIMO or multiple UEs for multi-user MIMO.
    Type: Grant
    Filed: August 16, 2010
    Date of Patent: September 15, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Amir Farajidana, Tingfang Ji, Alexei Yurievitch Gorokhov, Anastasios Stamoulis
  • Publication number: 20150257138
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. In an aspect, the apparatus may determine whether a starting symbol of an enhanced physical downlink control channel (EPDCCH) is an initial symbol in a subframe based on an EPDCCH configuration. Based on the determination, the apparatus may refrain from decoding a subset of legacy control channels in the subframe when the starting symbol of the EPDCCH is the initial symbol in the subframe. The legacy control channel may comprise at least one of a physical control format indicator channel (PCFICH), a physical hybrid-ARQ indicator channel (PHICH), or a combination thereof.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 10, 2015
    Inventors: Wanshi CHEN, Stefan GEIRHOFER, Peter GAAL, Hao XU, Tao LUO
  • Publication number: 20150257139
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. In an aspect, the apparatus may configure at least a first resource set and a second resource set for a control channel. The first and second resource sets may be configured with a common reference signal configuration. The apparatus also configures first rate-matching parameters for the first resource set and second rate-matching parameters for the second resource set. Then, the apparatus transmits the first rate-matching parameters and the second rate-matching parameters and transmits the control channel using the first resource set and the second resource set.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 10, 2015
    Inventors: Wanshi CHEN, Stefan GEIRHOFER, Peter GAAL, Hao XU, Tao LUO
  • Publication number: 20150257137
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. In an aspect, the apparatus may determine at least a first and second resource set configured for a control channel and may determine a common set of aggregation levels for the first and second resource sets. The apparatus may further determine first rate-matching parameters for the first resource set and second rate-matching parameters for the second resource set, and may process the control channel using the common set of aggregation levels and the first and second rate-matching parameters.
    Type: Application
    Filed: May 21, 2015
    Publication date: September 10, 2015
    Inventors: Wanshi CHEN, Stefan GEIRHOFER, Peter GAAL, Hao XU, Tao LUO
  • Patent number: 9113463
    Abstract: Certain aspects of the present disclosure provide techniques for managing resources utilized for enhanced physical downlink control channel (PDCCH) transmissions. According to certain aspects, a method is provided for wireless communications which may be performed, for example, by a user equipment (UE). The method generally includes receiving signaling indicating a set of time and frequency resources in one or more subframes allocated for an enhanced physical downlink control channel (PDCCH), receiving a downlink transmission in a subframe, making a determination to monitor for the enhanced PDCCH in the subframe based on the signaling, and decoding the enhanced PDCCH transmitted using the set of time and frequency resources in the subframe, in response to the determination.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: August 18, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Wanshi Chen, Peter Gaal, Tao Luo, Jelena Damnjanovic, Stefan Geirhofer
  • Patent number: 9054842
    Abstract: One aspect of the present disclosure provides various configurations of the macro cell and remote radio heads to allow legacy UEs to function, including mapping CRS ports to physical antenna, configuring CSI-RS transmissions and assisting the new UE in identifying remote radio heads.
    Type: Grant
    Filed: February 13, 2012
    Date of Patent: June 9, 2015
    Assignee: QUALCOMM INCORPORATED
    Inventors: Kapil Bhattad, Wanshi Chen, Peter Gaal, Stefan Geirhofer, Tingfang Ji, Juan Montojo
  • Patent number: 9055582
    Abstract: Certain aspects of the present disclosure provide techniques for managing resources utilized for enhanced physical downlink control channel (PDCCH) transmissions. According to certain aspects, a method is provided for wireless communications which may be performed, for example, by a user equipment (UE). The method generally includes receiving signaling indicating a set of time and frequency resources in one or more subframes allocated for an enhanced physical downlink control channel (PDCCH), receiving a downlink transmission in a subframe, making a determination to monitor for the enhanced PDCCH in the subframe based on the signaling, and decoding the enhanced PDCCH transmitted using the set of time and frequency resources in the subframe, in response to the determination.
    Type: Grant
    Filed: November 1, 2012
    Date of Patent: June 9, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Wanshi Chen, Peter Gaal, Tao Luo, Jelena Damnjanovic, Stefan Geirhofer
  • Patent number: 9049695
    Abstract: Techniques are provided for association decisions by a user equipment (UE) or the like. In one example, there is provided a method that may involve discovering a peer UE, and determining a first metric for the peer UE. The method may further involve determining a second metric for a base station in a wireless area network (WAN). The method may further involve deciding whether to associate with the peer UE for peer-to-peer (P2P) communication or with the WAN for communication via the base station based on the first and second metrics. For example, the first metric may be determined based on received power of the peer UE at the first UE, and the second metric may be determined based on received power of the base station at the first UE.
    Type: Grant
    Filed: November 15, 2011
    Date of Patent: June 2, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Anastasios Stamoulis, Stefan Geirhofer, Jaber Mohammad Borran
  • Publication number: 20150146673
    Abstract: Aspects disclosed herein relate to channel and interference estimations in a coordinated multi-point (CoMP) environment. In the disclosed aspects, an eNB may be equipped to signal an identifier indicating a plurality of resource patterns, each associated with a resource pattern group, and each including a first resource element pattern for channel estimation and a second resource element pattern for interference estimation. The UE may be equipped to receive the signaling and perform channel estimation based at least in part on the first resource element pattern, and interference estimation based at least in part on the second resource pattern generate at least one channel state report based on the channel and interference estimations, and transmit at least one channel state report to an eNB. The eNB may determine one or more resources for use by the UE based on the at least one received channel state report.
    Type: Application
    Filed: February 2, 2015
    Publication date: May 28, 2015
    Inventors: Stefan GEIRHOFER, Wanshi CHEN, Tao LUO, Peter GAAL, Hao XU
  • Publication number: 20150131634
    Abstract: A method for wireless communication is provided which includes receiving first and second signals transmitted from first and second antennas, respectively, determining a time offset between the first and second antennas based on the first and second signals, and reporting information regarding the time offset, including information regarding the time offset as being above or below a predetermined threshold. Another method for wireless communication is provided which includes generating channel state information feedback based on an assumption that the time offset is being compensated at a transmitter side. Yet another method for wireless communication is provided which includes receiving information regarding a time offset between multiple transmit antennas, including information regarding the time offset as being above or below a predetermined threshold, and adapting downlink transmissions to account for the time offset.
    Type: Application
    Filed: January 21, 2015
    Publication date: May 14, 2015
    Inventors: Tao Luo, Stefan Geirhofer, Peter Gaal
  • Patent number: 9008582
    Abstract: Certain aspects of the present disclosure provide techniques for measuring interference observed at a CoMP UE caused by neighbor base stations transmitting reference signals.
    Type: Grant
    Filed: August 23, 2012
    Date of Patent: April 14, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Alan Barbieri, Tingfang Ji, Peter Gaal, Stefan Geirhofer, Yichao Huang
  • Patent number: 8995400
    Abstract: Aspects disclosed herein relate to channel and interference estimations in a coordinated multi-point (CoMP) environment. In the disclosed aspects, an eNB may be equipped to signal an identifier indicating a plurality of resource patterns, each associated with a resource pattern group, and each including a first resource element pattern for channel estimation and a second resource element pattern for interference estimation. The UE may be equipped to receive the signaling and perform channel estimation based at least in part on the first resource element pattern, and interference estimation based at least in part on the second resource pattern generate at least one channel state report based on the channel and interference estimations, and transmit at least one channel state report to an eNB. The eNB may determine one or more resources for use by the UE based on the at least one received channel state report.
    Type: Grant
    Filed: January 25, 2012
    Date of Patent: March 31, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Wanshi Chen, Tao Luo, Peter Gaal, Hao Xu
  • Patent number: 8964657
    Abstract: An apparatus and method for providing encoded information pertaining to a user-specific reference signal associated with a user equipment in a multiple access wireless communication system are provided. The encoded information jointly indicates a rank of transmission together with at least one parameter relating to the user-specific reference signal, such as a set of antenna ports and a user-specific reference signal pattern. The encoded information is transmitted in a downlink control channel to reduce overhead in the channel.
    Type: Grant
    Filed: November 1, 2010
    Date of Patent: February 24, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Amir Farajidana, Alexei Yurievitch Gorokhov, Juan Montojo, Stefan Geirhofer
  • Publication number: 20150036761
    Abstract: Provided is a method of wireless communication which includes selecting a codebook from a plurality of codebooks in accordance with an antenna characteristic, and transmitting an indication of the selected codebook. Each of the plurality of codebooks is associated with one of a plurality of antenna characteristics. In some designs, channel state information is received from a user equipment. The channel state information may be used to determine downlink scheduling and/or precoding. In some designs, the channel state information may include feedback elements associated with different subband granularity. The feedback elements may also indicate a selection of a subset of precoder column vectors and/or a phase offset between two groups of transmit antennas.
    Type: Application
    Filed: October 10, 2014
    Publication date: February 5, 2015
    Inventors: Peter GAAL, Stefan GEIRHOFER, Juan MONTOJO
  • Patent number: 8937906
    Abstract: Aspects of the present disclosure relate generally to wireless communication systems, and more particularly, to defining a structure of and enhanced physical downlink control channel (e-PDCCH). Certain aspects provide methods and apparatus for determining a search space in which a base station (eNodeB) may transmit an enhanced physical downlink control channel (e-PDCCH), wherein the search space comprises one or more fractional portions of frequency-time resources of a physical resource block (PRB) pair, and attempting to decode the e-PDCCH based on the determined search space.
    Type: Grant
    Filed: October 31, 2012
    Date of Patent: January 20, 2015
    Assignee: QUALCOMM Incorporated
    Inventors: Wanshi Chen, Peter Gaal, Yongbin Wei, Juan Montojo, Tao Luo, Hao Xu, Stefan Geirhofer, Jelena Damnjanovic, Aleksandar Damnjanovic
  • Publication number: 20140376517
    Abstract: According to example embodiments, a method for wireless communications includes identifying at least one UE capable of being served by a plurality of transmission points (TPs) on a first frequency or by a relay on a second frequency, evaluating a first performance metric conditioned on the UE being served by the relay and a second performance metric conditioned on the UE being served by the plurality of TPs, deciding whether the UE should be served by the plurality of TPs on the first frequency or by the relay on the second frequency, based, at least in part, on the first and second performance metrics, and taking action to switch the UE to or from being served by the relay or the plurality of TPs, based on the decision.
    Type: Application
    Filed: June 24, 2014
    Publication date: December 25, 2014
    Inventors: Stefan GEIRHOFER, Alan BARBIERI, Naga BHUSHAN, Peter GAAL
  • Patent number: 8913511
    Abstract: Techniques for performing interference management to support peer-to-peer (P2P) communication in a wide area network (WAN) are described. In an aspect, interference management may be performed in a coordinated manner for/by a set of server nodes, which may include a P2P server and at least one neighbor server node of the P2P server. The P2P server may be a UE communicating peer-to-peer with at least one other UE or P2P client. Interference management may be performed for the set of server nodes to reduce interference to the P2P server and/or the at least one P2P client. In one design, active sets may be determined for UEs. The active set of each UE may include nodes received with sufficient strength by that UE. The set of server nodes may be determined based on the active sets of the P2P server, the at least one P2P client, and possibly other UEs.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: December 16, 2014
    Assignee: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Ravi Palanki, Jaber Mohammad Borran, Naga Bhushan
  • Patent number: 8891652
    Abstract: Provided is a method of wireless communication which includes selecting a codebook from a plurality of codebooks in accordance with an antenna characteristic, and transmitting an indication of the selected codebook. Each of the plurality of codebooks is associated with one of a plurality of antenna characteristics. In some designs, channel state information is received from a user equipment. The channel state information may be used to determine downlink scheduling and/or precoding. In some designs, the channel state information may include feedback elements associated with different subband granularity. The feedback elements may also indicate a selection of a subset of precoder column vectors and/or a phase offset between two groups of transmit antennas.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: November 18, 2014
    Assignee: Qualcomm Incorporated
    Inventors: Peter Gaal, Stefan Geirhofer, Juan Montojo
  • Publication number: 20140334402
    Abstract: A method of wireless communications identifies a first virtual cell identity. The method also includes determining one or more virtual cells based on the identified first virtual cell identity. The method further includes processing one channel based on the determination.
    Type: Application
    Filed: May 8, 2014
    Publication date: November 13, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Wanshi CHEN, Tao LUO, Stefan GEIRHOFER, Peter GAAL, Hao XU
  • Publication number: 20140301271
    Abstract: A method of wireless communication includes transmitting channel state information reference signal (CSI-RS) configuration information to a user equipment (UE). The CSI-RS configuration information is transmitted so that the UE may mitigate interference caused by interfering CSI-RSs. The CSI-RS configuration may be a CSI-RS configuration of a neighbor cell.
    Type: Application
    Filed: April 2, 2014
    Publication date: October 9, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Hao XU, Wanshi CHEN, Tao LUO, Peter GAAL, Taesang YOO, Yongbin WEI, Durga Prasad MALLADI, Stefan GEIRHOFER