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).

  • Publication number: 20140301297
    Abstract: Certain aspects of the present disclosure relate to methods and apparatus for adaptive antenna management in LTE. Devices and networks capable of transmitting and receiving signals using a variable number of transmitting or receiving antennas using LTE radio access technology are described.
    Type: Application
    Filed: April 2, 2014
    Publication date: October 9, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan GEIRHOFER, Wanshi CHEN, Peter GAAL, Hao XU, Xiaoxia ZHANG, Ashok MANTRAVADI, Tao LUO
  • Publication number: 20140301293
    Abstract: Determination of channel state information (CSI) feedback by mobile devices is disclosed in which the mobile device receives one or more configuration parameters, that may include one or more control channel parameters for configuring a mobile device control channel. The UE uses the configuration parameters to determine an assumption of overhead resources. Using this overhead assumption, the mobile device derives the CSI index and transmits the CSI index to a serving base station.
    Type: Application
    Filed: March 26, 2014
    Publication date: October 9, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Peter Gaal, Wanshi Chen
  • Publication number: 20140254701
    Abstract: A method for channel state information (CSI) reporting by a wireless communication device is described. The method includes determining a codebook for a CSI report corresponding to four transmit antenna (4Tx) transmissions from a base station. The codebook has a dual codebook structure. The method also includes generating the CSI report using the codebook. The method further includes transmitting the CSI report to a base station.
    Type: Application
    Filed: March 6, 2014
    Publication date: September 11, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Peter Gaal, Wanshi Chen, Hao Xu
  • Publication number: 20140204782
    Abstract: According to example embodiments, a method for wireless communications by a user equipment (UE) is included. The method generally includes performing channel estimation at a plurality of frequency locations based on reference signals (RS) transmitted from at least one transmission point, computing at least one channel feedback metric for each frequency location, and transmitting the channel feedback metrics to the transmission point. According to certain aspects, a method for wireless communications by a base station (BS) is provided. The BS may receive channel feedback metrics from a UE, calculated at a plurality of frequency locations based on RSs transmitted from the BS. The BS may perform interpolation to determine values for channel feedback metrics for frequency locations between frequency locations of the received channel feedback metrics.
    Type: Application
    Filed: January 15, 2014
    Publication date: July 24, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan GEIRHOFER, Peter GAAL, Naga BHUSHAN, Alan BARBIERI
  • Publication number: 20140204848
    Abstract: Certain aspects of the present disclosure generally relate to resolving ambiguous user equipment (UE) capability signaling. According to certain aspects, a method for wireless communications by a UE is provided. The method generally includes determining capabilities of the UE to support at least one of multiple-input multiple-output (MIMO) or coordinated multipoint (CoMP) features on different operating frequency bands of a radio access network (RAN), signaling, to a base station (BS) of the RAN, a first combination of capabilities of the UE for a combination of bands, signaling, to the BS, a second combination of capabilities, different than the first combination of capabilities, for the combination of bands, and identifying, based on or more criteria, a particular combination of capabilities to be used to communicate with the BS. In certain aspects, the UE may identify the combination of capabilities to use by applying a deterministic rule.
    Type: Application
    Filed: November 20, 2013
    Publication date: July 24, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan GEIRHOFER, Wanshi CHEN, Peter GAAL, Hao XU
  • Publication number: 20140126490
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. In an aspect, the apparatus may receive a set of configurations for an EPDCCH that are tied to a set of configurations received for a PDSCH. The apparatus may then receive and process the EPDCCH based on at least one configuration from the set of configurations for the EPDCCH. In another 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: September 9, 2013
    Publication date: May 8, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Wanshi CHEN, Stefan GEIRHOFER, Peter GAAL, Hao XU, Tao LUO
  • Publication number: 20140112168
    Abstract: Enhanced sounding reference signal (SRS) transmissions for multiple input, multiple output (MIMO) operation are disclosed in which a user equipment (UE) detects an observed interference level for each receiver chain of the UE. In response to an imbalance, the UE precodes a SRS targeting downlink operation to indicate the imbalance. The UE then transmits the precoded SRS. In alternative aspects, the precoded SRS vector may be determined by an evolved nodeB (eNB). In such aspects, the eNB determines the precoded SRS vector targeting downlink operations for the served UEs, wherein the determined precoded SRS vector includes determining the precoded SRS vector on a per UE basis, enabling the precoded SRS vector for either one or both of frequency division duplex (FDD) systems and time division duplex (TDD) systems, or enabling the precoded SRS vector for aperiodic SRS only. The eNB then transmits the determined precoded SRS vector to the UE.
    Type: Application
    Filed: February 21, 2013
    Publication date: April 24, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Wanshi Chen, Peter Gaal, Hao Xu, Yongbin Wei, Stefan Geirhofer
  • Publication number: 20140092760
    Abstract: Methods and apparatus are provided for assigning interference measurement resources. A method includes receiving at least one identifier, which determines, at least in part, at least one interference measurement resource that partially overlaps with another at least one interference measurement resource. The at least one interference measurement resource comprises a number of resource elements out of a set of resource elements. The method also includes measuring interference based at least in part on the at least one interference measurement resource.
    Type: Application
    Filed: February 28, 2013
    Publication date: April 3, 2014
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Peter Gaal, Yongbin Wei
  • Publication number: 20140036806
    Abstract: Certain aspects of the present disclosure relate to methods and apparatus for Coordinated Multipoint (CoMP) communications. Certain aspects relate to methods and apparatus for determining resource mapping and/or rate matching for CoMP operations.
    Type: Application
    Filed: July 25, 2013
    Publication date: February 6, 2014
    Applicant: QUALCOMM INCORPORATION
    Inventors: Wanshi Chen, Hao Xu, Peter Gaal, Tao Luo, Stefan Geirhofer, Aleksandar Damnjanovic
  • Publication number: 20140036804
    Abstract: Certain aspects provide methods and apparatus for processing a control channel and/or a shared channel in a subframe based on a determination that one or more channel properties of the two channels are substantially the same. One example method generally includes receiving a control channel and a shared channel within a subframe; determining that one or more channel properties of the control channel and the shared channel in the subframe are substantially the same; and processing the control channel and the shared channel based on the determination. In this manner, estimations determined for a first channel may be assumed for a second channel whose channel properties are substantially the same as the first channel, rather than by separately determining the estimations for the second channel, thereby saving processing time.
    Type: Application
    Filed: July 23, 2013
    Publication date: February 6, 2014
    Applicant: QUALCOMM Incorporated
    Inventors: Wanshi Chen, Peter Gaal, Stefan Geirhofer, Hao Xu
  • Publication number: 20130343301
    Abstract: Certain aspects of the present disclosure provide methods and apparatus for joint support of coordinated multipoint (CoMP) operations and carrier aggregation (CA). One method generally includes receiving signaling indicating a configuration, from a set of possible configurations, that defines how the UE is to communicate with one or more base stations (BSs) using coordinated multipoint (CoMP) operations on one or more component carriers (CCs) and communicating in accordance with the configuration.
    Type: Application
    Filed: June 20, 2013
    Publication date: December 26, 2013
    Inventors: Stefan Geirhofer, Wanshi Chen, Hao Xu, Peter Gaal
  • Publication number: 20130308714
    Abstract: Aspects of the present disclosure relate to techniques that may be utilized in networks with base stations and/or mobile devices that use large number of antennas or multi-dimensional arrays of antennas.
    Type: Application
    Filed: May 16, 2013
    Publication date: November 21, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Hao Xu, Stefan Geirhofer, Peter Gaal, Wanshi Chen, Yongbin Wei
  • Patent number: 8588801
    Abstract: Providing for a multipoint equalization (MPE) framework for coordinated multipoint (CoMP) transmission in wireless communication is described herein. The disclosed MPE framework involves distributed scheduling decisions for CoMP transmission, reducing complexity of scheduling coordination as compared with centralized scheduling techniques that coordinate scheduling decisions for multiple network base stations. Further, the MPE framework involves distributed computation of CoMP transmission coefficients, relying on a maximum of two backhaul hops to obtain information for the computation, and disseminate the transmission coefficients. The disclosed MPE framework shows substantial gains in various network deployments over conventional CoMP techniques.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: November 19, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Alexei Yurievitch Gorokhov, V. Sreekanth Annapureddy, Alan Barbieri, Siddhartha Mallik, Stefan Geirhofer
  • Publication number: 20130301560
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided in which downlink transmission modes in a wireless network are semi-statically configured for a mobile terminal in multiple-input multiple-output (MIMO) operation. The apparatus provides multiple precoding matrix indicators (PMIs) for a plurality of ranks. The provision of multiple PMIs by the apparatus enables balanced performance among different ranks and avoids less than optimal performance observed when the apparatus provides only a single rank and PMI that are generally not optimal for all transmissions. Feedback configuration information received by an apparatus defines a plurality of channel state information feedback instances conditioned on an admissible rank value. Rank indicators (RIs) and PMIs corresponding to the feedback instances are determined and feedback is provided for the channel state information feedback instances.
    Type: Application
    Filed: May 3, 2013
    Publication date: November 14, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan GEIRHOFER, Wanshi CHEN, Peter GAAL, Yongbin WEI, Naga BHUSHAN
  • Publication number: 20130301450
    Abstract: Certain aspects of the present disclosure provide methods and apparatus for performing coordinated multipoint (CoMP) channel state information (CSI) feedback under multiple channel and interference assumptions. One method generally includes receiving signaling indicating at least one or more interference measurement resources (IMRs) from a network and a configuration with one or more non-zero power reference signal (NZP-RS) resources in which one or more base stations transmit a RS, performing separate interference measurements at least on a per-IMR basis in one or more subframes by forming a baseline interference estimate based on the IMR and forming separate interference estimates based on adding interference from selected NZP-RS resources to the baseline interference estimate, and transmitting one or more CSI feedback reports that correspond to the interference measurements.
    Type: Application
    Filed: May 9, 2013
    Publication date: November 14, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Wanshi Chen, Peter Gaal, Yongbin Wei
  • Publication number: 20130301570
    Abstract: A method of wireless communications includes adapting to downlink/uplink resource allocations. In particular, the downlink/uplink communications may be adjusted according to time division duplexed (TDD) configurations of serving and neighbor cells.
    Type: Application
    Filed: May 9, 2013
    Publication date: November 14, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Hao XU, Wanshi CHEN, Peter GAAL, Stefan GEIRHOFER
  • Publication number: 20130294268
    Abstract: A method for mitigating interference in a wireless network includes an eNodeB and/or a UE identifying interference. The eNodeB may identify the interfering TDD configurations based on a downlink signal of a neighboring eNodeB received during an uplink timeslot for a UE associated with the eNodeB. Likewise, the UE may identify an interfering UE based on an uplink signal received during a downlink timeslot for an eNodeB associated with the UE. The eNodeB performs interference management based at least in part on the identified interference.
    Type: Application
    Filed: April 29, 2013
    Publication date: November 7, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Hao Xu, Wanshi Chen, Peter Gaal, Stefan Geirhofer, Yongbin Wei
  • Publication number: 20130286904
    Abstract: Transmission of control data by a user equipment (UE) in circumstances following a TDD subframe reconfiguration from an evolved node B (eNB) may result in a conflict with a scheduled transmission of the control data. In one example, a UE may modify periodicity, content, priority, or other aspects of channel state information (CSI) or sounding reference signals (SRS) to resolve any conflicts resulting from a TDD subframe reconfiguration and to ensure transmission of the CSI or SRS. In another example, a UE may detect a hybrid automatic repeat request (HARQ) conflict resulting from a TDD subframe reconfiguration. In such example, the UE may determine and apply a HARQ soft buffer size for a HARQ process or determine and apply a codebook size for a HARQ process in carrier aggregation to resolve such HARQ conflict.
    Type: Application
    Filed: April 25, 2013
    Publication date: October 31, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Hao Xu, Wanshi Chen, Peter Gaal, Stefan Geirhofer
  • Publication number: 20130286965
    Abstract: Aspects of the present disclosure relate to techniques that may be utilized in networks with relatively dense deployments of nodes, such as remote radio heads (RRHs) and UE relays.
    Type: Application
    Filed: April 25, 2013
    Publication date: October 31, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Hao Xu, Durga Prasad Malladi, Yongbin Wei, Peter Gaal, Wanshi Chen, Tao Luo, Aleksandar Damnjanovic, Stefan Geirhofer
  • Publication number: 20130258965
    Abstract: A method of wireless communication includes determining a capability for a number of channel state information configurations supported by a user equipment (UE). The channel state information processes link a channel measurement report with an interference measurement report. The UE transmits the capability to an eNodeB. Additionally, the UE receives CSI process configurations. The CSI process configurations identify CSI processes that can be requested by the eNodeB.
    Type: Application
    Filed: March 14, 2013
    Publication date: October 3, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Wanshi Chen, Peter Gaal