Abstract: Aspects describe utilizing a dedicated reference signal for supporting Network MIMO, distributed MIMO, Coordinated MultiPoint, and the like. A data modulation symbol is transmitting in the same direction as a pilot modulation symbol is transmitted. Two or more wireless devices can coordinate communications such that transmission of the same pilot modulation symbol and the same data modulation symbol are transmitted to a device in different directions, each direction associated with a wireless device and intended for a particular mobile device. Cluster-specific scrambling and/or user-group specific scrambling can be employed and a scrambling code can be communicated prior to transmission of the pilot modulation symbols and data modulation symbols.

Abstract: Methods, systems, and devices are described for providing periodic CSI reports and/or aperiodic CSI reports to provide CSI for both anchor and non-anchor TDD subframes in eIMTA. Periodic CSI reports may be provided based on a reference configuration, and aperiodic CSI reports may be provided based on a time of reception of a CSI request and a reference configuration. A UE may determine to report anchor or non-anchor CSI through explicit or implicit signaling. Aperiodic CSI may be used for transmission of anchor subframe CSI reports and periodic CSI may be used for transmission of non-anchor subframe CSI reports, or aperiodic CSI may be used for transmission of non-anchor subframe CSI reports and periodic CSI may be used for transmission of anchor subframe CSI reports. A determination of the reference subframe for aperiodic CSI estimation may be based on a time of receipt of an aperiodic CSI request.

Abstract: Aspects describe utilizing a dedicated reference signal for supporting Network MIMO, distributed MIMO, Coordinated MultiPoint, and the like. A data modulation symbol is transmitting in the same direction as a pilot modulation symbol is transmitted. Two or more wireless devices can coordinate communications such that transmission of the same pilot modulation symbol and the same data modulation symbol are transmitted to a device in different directions, each direction associated with a wireless device and intended for a particular mobile device. Cluster-specific scrambling and/or user-group specific scrambling can be employed and a scrambling code can be communicated prior to transmission of the pilot modulation symbols and data modulation symbols.

Abstract: A method, an apparatus, and a computer program product for wireless communication are provided. The apparatus receives, by a user equipment (UE) during a first subframe, an indication of a dynamic uplink/downlink (UL/DL) subframe configuration. The apparatus determines an uplink hybrid automatic repeat request (HARQ) timing based on an uplink reference subframe configuration and at least one of the dynamic UL/DL subframe configuration or a downlink reference subframe configuration. The apparatus selects an uplink subframe for communication based on the determined uplink HARQ timing.

Abstract: A method and apparatus for demapping a double squared quadrature amplitude modulated (DSQ) symbol is disclosed. One or more first log likelihood ratios (LLRs) are determined, for a first subset of constellation points of a corresponding DSQ constellation, using an LLR approximation. One or more second LLRs are determined, for a second subset of constellation points of the DSQ constellation, using a lookup table. The DSQ symbol is then demapped to one of a plurality of constellation points of the DSQ constellation based on the first and second LLRs. For some embodiments, the first subset of constellation points may correspond with an inner region of the DSQ constellation and the second subset of constellation points may correspond with an outer region of the DSQ constellation.

Abstract: The present disclosure relates to systems and methods for a two-dimensional discrete Fourier transform based codebook for elevation beamforming. A two-dimensional discrete Fourier transform based codebook is determined for elevation beamforming. The codebook supports single stream codewords and multistream codewords. The two-dimensional discrete Fourier transform based codebook is generated by stacking the columns of the matrix product of two discrete Fourier transform codebook matrices. The codebook size may be flexibly designed based on required beam resolution in azimuth and elevation. A best codebook index is selected from the generated two-dimensional discrete Fourier transform based codebook. The selected codebook index is provided in a channel state information report. The channel state information report is transmitted to a base station.

Abstract: A method of determining a distance estimate between a mobile device and a wireless transceiver communicating with the mobile device on at least one multi-carrier signal includes: receiving at least one multi-carrier signal; selecting at least one carrier signal from the at least one multi-carrier signal; measuring a signal characteristic of the at least one carrier signal from the at least one multi-carrier signal; and determining the distance estimate between the mobile device and the wireless transceiver based at least partially upon the signal characteristic.

Abstract: Aspects describe utilizing a dedicated reference signal for supporting Network MIMO, distributed MIMO, Coordinated MultiPoint, and the like. A data modulation symbol is transmitting in the same direction as a pilot modulation symbol is transmitted. Two or more wireless devices can coordinate communications such that transmission of the same pilot modulation symbol and the same data modulation symbol are transmitted to a device in different directions, each direction associated with a wireless device and intended for a particular mobile device. Cluster-specific scrambling and/or user-group specific scrambling can be employed and a scrambling code can be communicated prior to transmission of the pilot modulation symbols and data modulation symbols.

Abstract: Techniques for supporting distributed MIMO are described. For multi-user distributed MIMO, a cell directs its transmit power toward a UE while reducing interference to UE(s) in neighbor cell(s). For single-user distributed MIMO, multiple cells concurrently send transmissions to a UE. In an aspect, a UE sends channel estimates for serving and non-serving cells to support multi-user distributed MIMO. Each cell may use the channel estimates to select UEs for data transmission and determine precoding vectors to use for data transmission to the selected UEs. In another aspect, a UE sends CQI information for serving and non-serving cells to support single-user distributed MIMO. Each cell may use the CQI information to select UEs for data transmission and determine modulation and coding schemes to use for the selected UEs. In yet another aspect, a UE determines CQI information for a serving cell by taking into account interference nulling by non-serving cells.

Abstract: The various embodiments include methods and apparatuses for canceling nonlinear interference during concurrent communication of multi-technology wireless communication devices. Nonlinear interference may be estimated using a radial basis function neural network with Hammerstein structure by executing a radial basis function on aggressor signals at a hidden layer of the radial basis function neural network with Hammerstein structure to obtain hidden layer outputs, augmenting aggressor signal(s) by weight factors and, executing a linear combination of the augmented output, at an intermediate layer to produce a combined hidden layer outputs. At an output layer, a linear filter function may be executed on the hidden layer outputs to produce an estimated nonlinear interference used to cancel the nonlinear interference of a victim signal.

Abstract: Methods, systems, and-devices are described for interference mitigation in a time-division duplex(TDD)wireless communication system. First and second subframe types may be identified for TDD subframes to be transmitted using the system. Different power control parameters associated with each subframe type may be identified based on transmission directions in neighboring cells for the particular subframes. One or more TDD subframes to be transmitted may be identified as a first or second subframe type, and power control may be applied to the transmitted subframes according the power control parameter associated with the subframe type. The identification of subframes and power control parameters to be applied to each type of subframe may be transmitted, for example, to a user equipment(UE). The information may be transmitted to a UE, for example, via radio resource control(RRC)signaling or via a physical layer control channel.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for linear precoding in full-dimensional MIMO (FD-MIMO) systems. According to aspects, an eNB may compress a larger number of antenna elements to a smaller number of antenna ports. The eNB may use a port precoding matrix to transmit reference signals to a UE, receive feedback regarding CSI based on the reference signals, and transmit data to the UE, based on a mapping of multiple data layers and mapping of antenna ports to the physical antenna elements. Further, aspects include performing elevation beamforming by dynamically forming one or more vertical sectors based on UE feedback in the elevation domain.

Abstract: Methods, systems, and devices are described for interference mitigation between neighboring cells through the use of cell clusters and virtual logical cell clusters. Cells may be added to a cell cluster with a first cell when a level of interference coupling between the first cell and one or more neighboring cells exceeds a first threshold. One or more other cells may be added to a virtual logical cell cluster with the first cell when the level of interference coupling is between a second threshold and the first threshold, the second threshold being less than the first threshold. Interference mitigation between cells of cell clusters and/or virtual logical cell clusters may be performed. Interference mitigation may be accomplished through, for example, coordination of TDD uplink-downlink (UL-DL) configurations for cell clusters and scheduling-dependent interference management (SDIM) for virtual logical cell clusters.

Abstract: Flexible beamforming is disclosed in which a base station receives feedback from a user equipment (UE), in which the feedback is related to one or more reference signals transmitted by the base station. The base station will obtain a tilt adjustment based, at least in part, on the feedback and generate an elevation precoding vector based using the feed-back. Using the tilt adjustment and elevation precoding vector, the base station may then perform elevation beamforming with an antenna array of the base station for the UE.

Abstract: A method of data encoding is disclosed. A communications device receives a set of information bits to be encoded into a codeword (c), which includes the set of information bits and a set of parity bits. A first bit value is assigned to a first parity bit in the set of parity bits. The remaining parity bits are then encoded based, at least in part, on the first bit value assigned to the first parity bit. The device may encode the remaining parity bits using the set of information bits and a parity check matrix (H) for a low density parity check (LDPC) code. The device may also generate a new parity check matrix (H0) based on linearly independent rows of the parity check matrix H, and iteratively evaluate each of the remaining parity bits based on the equation: H0c=0. The device may then determine whether the encoded codeword c is a valid codeword given the LDPC code, and change one or more bit values of the codeword if c is not a valid codeword.

Abstract: Methods and apparatus are disclosed for interference management. The interference management is based on dynamic point selection or semi-static point selection. The method includes determining interference at a plurality of network nodes. The method includes selecting a transmission point from the plurality of network nodes for a transmission to at least one mobile entity based on the determined interference.

Abstract: Certain aspects of the present disclosure relate to methods and apparatus for measuring and mitigating interference. Such interference may include base station to base station (eNB to eNB) interference and/or UE to UE interference. A base station may determine a first subframe configuration for the base station and a second subframe configuration for one or more other base stations, wherein the first and second subframe configurations have different ratios of uplink to downlink portions. The base station may measure interference caused by the one or more other base stations based on reference signals transmitted in downlink portions of the second subframe configuration.

Abstract: A method for improved random access procedures by a UE is provided. The method comprises: measuring a common CSI-RS; selecting a best horizontal/vertical beam from a set of fixed beams; determining a preamble mapped to the selected horizontal/vertical beam; transmitting the preamble; and receiving a random access response.

Abstract: Methods, systems, and apparatuses are described for channel estimation in wireless communications. The method, systems, and apparatuses operate in a time-division duplex (TDD) scheme. A first transmission may be received in a first sub-frame of a channel according to the TDD scheme. A time auto-correlation function may be applied to the first transmission to obtain a first auto-correlation sample. At least one characteristic of the channel may be estimated based at least in part on the first auto-correlation sample.

Abstract: A method of error correction using low density parity check (LDPC) codes is disclosed. A communications device receives a codeword and detects one or more bit errors in the received codeword using an LDPC code. The device then generates a corrected codeword based, at least in part, on a set of unsatisfied check nodes of the LDPC code. The device may determine that the one or more bit errors are associated with an absorption set of the LDPC code. The device may also determine a plurality of candidate codewords based on the set of unsatisfied check node and select the corrected codeword from the plurality of candidate codewords. Each of the plurality of candidate codewords may represent a valid codeword associated with the LDPC code.