Qualcomm Incorporated

Xiliang Luo

Juan Montojo

Peter S Gaal

Wanshi Chen

Xiaoxia Zhang

Tao Luo

Hao Xu

Kapil Bhattad

Taesang Yoo

Durga Prasad Malladi

Ke Liu

Tingfang Ji

Aleksandar Damnjanovic

Jelena Damnjanovic

Alexei Yurievitch Gorokhov

Yongbin Wei

Ravi Palanki

Amir Farajidana

Keith William Saints

Naga Bhushan

Yi Huang

Arumugam Chendamarai Kannan

Aamod Dinkar Khandekar

Rashid Ahmed Akbar Attar

Christopher G Lott

Mohammad Jaber Borran

Wenshu Zhang

Hisham A Mahmoud

Jelena M Damnjanovic

Certain aspects of the present disclosure relate to techniques for power control and user multiplexing for coordinated multi-point (CoMP) transmission and reception in heterogeneous networks (HetNet).

Power control and user multiplexing for heterogeneous network coordinated multipoint operations

Bits for acknowledgement (ACK) and/or negative acknowledgement (NAK) may be allocated based on whether a special subframe configuration in a TDD configuration permits downlink transmission. For carrier aggregation, ACK/NAK bits may be allocated only to special subframes in component carriers (CCs) which permit downlink transmission. Also, for example, ACK/NAK bits may be allocated to all CC special subframes if a single CC is configured to allow downlink transmission on one of its special subframes. ACK/NAK bits may also be allocated to all special subframes.

Acknowledgement / negative acknowledgement feedback for TDD

Techniques are provided for combining different types of reference signals. A wireless communications network may be configured to allow a user equipment (UE) to combine multiple demodulation reference signals (DM-RSs) to support demodulation of a physical downlink shared channel (PDSCH), and/or other downlink transmissions, transmitted from a base station to the UE. The base station may provide explicit signaling that reference signals transmitted in two or more transmission time intervals may be combined, or a determination that reference signals transmitted in two or more transmission time intervals may be combined may be made implicitly based on system configuration and previous transmissions. Based on the explicit signaling and/or implicit determination, a UE may combine reference signals included in each of two or more reference signals for use in demodulation of downlink transmissions.

Reference signal transmission and averaging for wireless communications

Techniques for sending control information relating to multiple downlink carriers and data on a single uplink carrier are described. A user equipment (UE) may be scheduled to transmit on a designated uplink carrier. The UE can multiplex control information for multiple downlink carriers with data for transmission on the uplink carrier in a same subframe. Multiplexing may be performed according to a type of the control information and/or an ordering, priority, or association of the downlink carriers. The UE can selectively encode the control information separately for each downlink carrier and/or jointly across downlink carriers. The control information may be mapped to a single layer or multiple layers of a data channel. The UE may send the multiplexed control information and data on the data channel in the subframe while maintaining a single-carrier waveform.

Feedback of control information for multiple carriers

Antenna selection and reassignment in multiple radio access technology (RAT) communication systems with unlicensed spectrum is disclosed. Aspects include a user equipment (UE) monitoring for a channel reserving signal in each frame from multiple transmission sources. If no channel reserving signal is detected, then the UE reassigns one or more of the antennas previously assigned to the transmission sources with no activity detected. Additional aspects include base stations that determine a clear channel assessment (CCA) status for each of unlicensed carrier designated for transmission to a UE. The base station will transmit a receive antenna usage adjustment signal to the UE based on the determined CCA status.

Antenna selection in LTE/LTE-A networks with unlicensed spectrum

A wireless communication method includes configuring a plurality of common sounding reference signal (SRS) subframes shared with one or more cooperating cells and providing an SRS configuration parameter to facilitate an orthogonal SRS transmission over at least one of the plurality of common SRS subframes.

Sounding reference signal enhancements for wireless communication

A wireless communication method includes allocating physical uplink control channel (PUCCH) data in first slot to a first orthogonal cover code (OCC). The method also includes allocating PUCCH data in a second slot of the same subframe to a different orthogonal cover code (OCC). Another method includes mapping PUCCH resources to physical resource blocks based on a user equipment (UE) specific signaling parameter (e.g., a resource index) and a number of symbols in a slot of a subframe.

Resource assignments for uplink control channel

Methods and apparatus for selecting samples for secondary synchronization signal (SSS) detection are described. Several alternatives are provided for efficient cell identifier detection. In a first alternative, multiple bursts of a signal received from a cell are sampled with non-uniform spacing between sampling intervals to determine a sequence for cell identification. In a second alternative, samples of a first and a second signal received from a stronger cell are cancelled, and a sequence for detecting a weaker cell is determined by reducing effects of the samples of a third signal received from the weaker cell which do not overlap with the primary synchronization signal (PSS) or SSS of the stronger cell. In a third alternative, a sequence for detecting a weaker cell is determined by reducing effects of any sampled bursts that correspond to a high transmission power portion of a signal from a stronger cell.

Sample selection for secondary synchronization signal (SSS) detection

A precoding scheme to accommodate user equipment (UEs) having higher Doppler speeds. In such transmission schemes, a different precoding matrix is applied to each orthogonal frequency division multiplex (OFDM) symbol in the transmission stream. Additionally, a downlink control message format is defined to handle assignment of multiple different transmission schemes using the same message format. The downlink control message format includes a control element in one of the message fields along with a set of parameters specifically applicable to the assigned transmission scheme. Based on the value of this control element, the UE sets the specific transmission scheme and determines a set of interpretation rules uniquely associated with that transmission scheme. Using the interpretation rules, the UE is able to read the set of parameters as applied to the selected transmission scheme.

Open loop MIMO mode for LTE-A uplink

Provided is a method for wireless communication which includes transmitting codewords according to an initial transmission rank, receiving downlink transmissions indicating at least one of the codewords to be retransmitted, constructing a demodulation reference signal (DM-RS) to be sent with the at least one codeword to be retransmitted, and retransmitting the at least one codeword with the DM-RS according to a retransmission rank. The downlink transmissions may include one or more physical hybrid automatic retransmission request indicator channels and the DM-RS may be constructed based at least in part on information in the downlink transmissions.

Demodulation reference signals for retransmission in wireless communication

Methods and apparatuses are provided for determining cyclic shift (CS) values and/or orthogonal cover codes (OCC) for a plurality of demodulation reference signals (DM-RS) transmitted over multiple layers in multiple-input multiple-output (MIMO) communications. A CS index can be received from a base station in downlink control information (DCI) or similar signaling. Based at least in part on the CS index, CS values for the plurality of DM-RS can be determined. In addition, OCC can be explicitly signaled or similarly determined from the CS index and/or a configured CS value received from a higher layer. In addition, controlling assignment of CS indices and/or OCC can facilitate providing orthogonality for communications from paired devices in multiuser MIMO.

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San Diego, CA, United States of America

Xiliang Luo