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: 20130250913
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided for separating control transmissions and data transmissions within the coverage area of a plurality of transmission/reception points or points that are geographically displaced, the plurality of points comprising a macro node and a plurality of remote radio heads (RRHs) coupled to the macro node. Separating control transmissions and data transmissions in the macro node/RRH configuration may allow UEs to be associated with one set of transmission points for data transmissions and the same set or a different set of transmission points for common control signaling. Separating control transmissions and data transmissions may also allow for faster reconfiguration of antenna ports used for UE data transmission compared with reconfiguration via a handover process.
    Type: Application
    Filed: May 15, 2013
    Publication date: September 26, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Tingfang Ji, Peter Gaal, Aleksandar Damnjanovic, Juan Montojo, Tao Luo, Wanshi Chen, Kapil Bhattad
  • Publication number: 20130242778
    Abstract: A method for wireless communication includes allocating overlapping sets of resources to different UEs. The resources may be for channel state information (CSI) measurement and received power measurements. The overlapping resources include a first set of resources, allocated to a first UE, for the CSI measurements and a second set of resources, allocated to a second UE, for the received power measurements. The method also includes receiving a CSI measurement report and a received power measurement report. The reports are based on the first set of resources and the second set or resources, respectively.
    Type: Application
    Filed: March 6, 2013
    Publication date: September 19, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Wanshi Chen, Hao Xu, Peter Gaal
  • Publication number: 20130242895
    Abstract: A method of wireless communication includes determining how to handle a collision between the first sounding reference signal (SRS) and a second SRS when the second SRS may the same type as the first SRS and when both the first SRS and the second SRS may be transmitted in a same cell. The method also includes transmitting the first SRS and the second SRS based on a received first and second configuration for SRSs. The first configuration includes a first UE specific cell identification that differs from a second UE specific cell identification of the second configuration and/or a first power offset that differs from a second power offset of the second configuration.
    Type: Application
    Filed: January 31, 2013
    Publication date: September 19, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Wanshi Chen, Peter Gaal, Hao Xu, Stefan Geirhofer
  • Publication number: 20130235911
    Abstract: A wireless communication device for sending quantization quality feedback is described. The wireless communication device includes a receiver that receives a signal. The wireless communication device also includes channel estimation circuitry coupled to the receiver. The channel estimation circuitry generates a channel estimate based on the signal. The wireless communication device also includes feedback determination circuitry coupled to the channel estimation circuitry. The feedback determination circuitry generates quantization quality feedback based on the channel estimate. The wireless communication device also includes a transmitter coupled to the feedback determination circuitry. The transmitter transmits the quantization quality feedback.
    Type: Application
    Filed: September 6, 2012
    Publication date: September 12, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Peter Gaal
  • Publication number: 20130235821
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided in which a cell identifier is selected based on one or more properties associated with received downlink control information (DCI), where the properties may not be exclusively associated with determining a cell identifier. The cell identifier may be selected from a plurality of cell identifiers received through radio resource control signaling. The properties of the DCI may include a type of download control channel, a type of subframe and a type of DCI format used to provide the DCI.
    Type: Application
    Filed: March 11, 2013
    Publication date: September 12, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Wanshi CHEN, Stefan GEIRHOFER, Peter GAAL, Tao LUO, Hao XU
  • Publication number: 20130053077
    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: Application
    Filed: August 23, 2012
    Publication date: February 28, 2013
    Applicant: QUALCOMM Incorporated
    Inventors: Alan Barbieri, Tingfang Ji, Peter Gaal, Stefan Geirhofer, Yichao Huang
  • Publication number: 20130051240
    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: Application
    Filed: February 13, 2012
    Publication date: February 28, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Kapil Bhattad, Wanshi Chen, Peter Gaal, Stefan Geirhofer, Tingfang Ji, Juan Montojo
  • Publication number: 20130028182
    Abstract: Certain aspects of the present disclosure provide techniques for implicitly linking aperiodic channel state information (A-CSI) reports to CSI-reference signal (CSI-RS) resources. In an aspect, the UE may be instructed to report on specific CSI-RS resource(s) via explicit signaling in the UE grant. Other aspects disclose techniques for implicit CSI-RS resource selection by the UE that require fewer signaling resources. Instead of explicitly signaling CSI-RS resources to the UE, the UE may implicitly select CSI-RS resource for CSI feedback reporting based on information known to the UE, e.g. a subframe on which a reporting request is received. This may reduce the impact of the additional signaling in the UE grant.
    Type: Application
    Filed: January 27, 2012
    Publication date: January 31, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Tao Luo, Wanshi Chen, Peter Gaal, Hao Xu, Kapil Bhattad, Tingfang Ji
  • Publication number: 20130021926
    Abstract: In macro/RRH setups, channel state information reference signals (CSI-RS) and demodulation reference signals (DM-RS) may be used to decouple control and data transmission. Data transmission (e.g. for LTE Rel 10 and beyond) may be based on CSI-RS and DM-RS, while control may be received from a different set of cells or TxPs via CRS. Certain aspects of the present disclosure introduce a reporting framework, in which configuration of data-serving cells/TxPs may be carried out based on CSI-RS. In certain aspects, a new concept of CSI-RS groups, i.e., a set of CSI-RS ports that a UE considers as one group for precoding matrix indicator (PMI)/channel quality indicator (CQI)/rank indicator (RI) reporting, may be defined.
    Type: Application
    Filed: January 26, 2012
    Publication date: January 24, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Tao Luo, Wanshi Chen, Peter Gaal, Hao Xu, Kapil Bhattad, Tingfang Ji
  • Publication number: 20120207043
    Abstract: Aspects disclosed herein relate to channel and interference estimations in a multiple transmission point environment including an eNB and RRHs. In the disclosed aspects, one or more transmission points can signal to a UE to measure channel state conditions based on a first and a second resource pattern. The UE may receive the signaling and perform interference estimation based at least in part on the first resource pattern, and channel estimation based at least in part on the second resource pattern. The UE may generate a channel state report based on the interference and channel estimations, and transmit the channel state report to a transmission point. The eNB may employ the received channel state report in scheduling one or more resources for use by the UE, and may select or adjust network traffic on the first and the second resource pattern, to affect the resulting channel and interference estimation.
    Type: Application
    Filed: December 23, 2011
    Publication date: August 16, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Tingfang Ji, Peter Gaal, Tao Luo, Wanshi Chen, Juan Montojo
  • Publication number: 20120207105
    Abstract: A method, an apparatus, and a computer program product for wireless communication are provided for separating control transmissions and data transmissions within the coverage area of a plurality of transmission/reception points or points that are geographically displaced, the plurality of points comprising a macro node and a plurality of remote radio heads (RRHs) coupled to the macro node. Separating control transmissions and data transmissions in the macro node/RRH configuration may allow UEs to be associated with one set of transmission points for data transmissions and the same set or a different set of transmission points for common control signaling. Separating control transmissions and data transmissions may also allow for faster reconfiguration of antenna ports used for UE data transmission compared with reconfiguration via a handover process.
    Type: Application
    Filed: January 12, 2012
    Publication date: August 16, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Tingfang Ji, Peter Gaal, Aleksandar Damnjanovic, Juan Montojo, Tao Luo, Wanshi Chen, Kapil Bhattad
  • Publication number: 20120208547
    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 clement 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: January 25, 2012
    Publication date: August 16, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Wanshi Chen, Tao Luo, Peter Gaal, Hao Xu
  • Publication number: 20120201158
    Abstract: In a cellular wireless communication system, peer-to-peer (P2P) links between mobile devices are implemented, and controlled using an aggregate utility metric for a group of P2P and cellular links. A mobile node participating in a P2P link, or an eNB, may periodically broadcast an activity level indicator indicating a resource-dependent activity level of the link. The node may control the activity level in response to utility metrics received from members of neighboring P2P links to maximize an aggregate utility of the link and the neighboring P2P links sharing at least a subset of resources of a common frequency spectrum. Formation or termination of P2P links may be controlled in response to comparing a calculated achievable utility value to a current utility value of a link, and taking action calculated to maximize the aggregate utility value.
    Type: Application
    Filed: February 1, 2012
    Publication date: August 9, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Jaber Mohammad Borran, Anastasios Stamoulis, Siddhartha Mallik, Ravi Palanki, Naga Bhushan
  • Publication number: 20120129562
    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: Application
    Filed: November 15, 2011
    Publication date: May 24, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Anastasios Stamoulis, Stefan Geirhofer, Jaber Mohammad Borran
  • Publication number: 20120057482
    Abstract: Certain aspects of the present disclosure relate to techniques for generating unified feedback framework for Multi User Multiple Input Multiple Output (MU-MIMO) enhancement based on indication of a preferred precoder pairings.
    Type: Application
    Filed: September 7, 2011
    Publication date: March 8, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Peter Gaal
  • Publication number: 20120044815
    Abstract: Techniques for supporting peer-to-peer (P2P) communication in a wide area network (WAN) are disclosed. In an aspect, interference coordination between P2P devices engaged in P2P communication and WAN devices engaged in WAN communication may be performed based on a network-controlled architecture. For the network-controlled architecture, P2P devices may detect other P2P devices and/or WAN devices and may send measurements (e.g., for pathloss, interference, etc.) for the detected devices to the WAN (e.g., serving base stations). The WAN may perform resource partitioning and/or association for the P2P devices based on the measurements. Association may include selection of P2P communication or WAN communication for a given P2P device. Resource partitioning may include allocation of resources to a group of P2P devices for P2P communication.
    Type: Application
    Filed: July 21, 2011
    Publication date: February 23, 2012
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Naga Bhushan, Ravi Palanki, Jaber Mohammad Borran, Aleksandar Damnjanovic
  • Publication number: 20120039412
    Abstract: Methods and apparatus for enforcing codebook properties (e.g., constant modulus and/or finite alphabet) in adaptive and dual-stage codebooks are described. One example method generally includes receiving multiple feedback aspects of a channel for wireless communications determining multiple codewords based on the multiple feedback aspects, determining a final precoding matrix based on the multiple codewords, enforcing at least one codebook property in at least one of the multiple codewords or the final precoding matrix, applying the final precoding matrix to a plurality of spatial streams to form precoded spatial streams, and transmitting the precoded spatial streams. For certain aspects, enforcing the at least one codebook property includes quantizing elements in each of the multiple codewords and/or the final precoding matrix to the nearest value in a finite alphabet or to increase a performance metric.
    Type: Application
    Filed: August 15, 2011
    Publication date: February 16, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Stefan Geirhofer, Peter Gaal, Juan Montojo
  • Publication number: 20120027113
    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: June 23, 2011
    Publication date: February 2, 2012
    Applicant: QUALCOMM INCORPORATED
    Inventors: Peter Gaal, Stefan Geirhofer, Juan Montojo
  • Publication number: 20110282989
    Abstract: Techniques for determining resources to use for peer-to-peer (P2P) communication are disclosed. In an aspect, a network entity may receive feedback information (e.g., resource usage information and/or channel state information) from P2P devices and may perform resource partitioning based on the feedback information to allocate some of the available resources for P2P communication. The allocated resources may observe little or no interference from devices engaged in wide area network (WAN) communication. In another aspect, P2P groups may perform resource negotiation via a WAN connection (e.g., with little or no involvement by the WAN) to assign the allocated resources to different P2P groups. In yet another aspect, a device may autonomously determine whether to communicate with another device directly or via a WAN, e.g., whether to initiate P2P communication with another device and whether to terminate P2P communication.
    Type: Application
    Filed: May 9, 2011
    Publication date: November 17, 2011
    Applicant: QUALCOMM Incorporated
    Inventors: Stefan Geirhofer, Naga Bhushan, Ravi Palanki, Aleksandar Damnjanovic, Parag Arun Agashe
  • Publication number: 20110268050
    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: Application
    Filed: November 1, 2010
    Publication date: November 3, 2011
    Applicant: QUALCOMM INCORPORATED
    Inventors: Amir Farajidana, Alexei Yurievitch Gorokhov, Juan Montojo, Stefan Geirhofer