Texas Instruments Corporation

Amazon Technologies, Inc.

Runhua Chen

Eko Nugroho Onggosanusi

Ralf Matthias Bendlin

Anthony Edet Ekpenyong

Vikram Chandrasekhar

Tarik Muharemovic

Badri N Varadarajan

Zukang Shen

Anand Ganesh Dabak

Il Han Kim

Pengfei Xia

Charles Kasimer Sestok, Iv

Timothy Leo Gallagher

Arunabha Ghosh

A base station selects a subset of at least one geographically separated antennas for each of the plurality of user equipments. The base station forms at least layer of data stream including modulated symbols, precodes the data stream via multiplication with the NT-by-N precoding matrix where N is the number of said layers and NT is the number of transmit antenna elements and transmits the precoded layers of data stream to the user equipment via the selected geographically separated antennas. The base station signals the subset of the plurality of geographically separated antennas via higher layer Radio Resource Control or via a down link grant mechanism. The base station optionally does not signal the subset of the plurality of geographically separated antennas to the corresponding mobile user equipment.

Downlink multiple input multiple output enhancements for single-cell with remote radio heads

An apparatus for mapping data in a wireless communication system. The apparatus includes circuitry for generating a precoding matrix for multi-antenna transmission based on a precoding matrix indicator (PMI) feedback from at least one remote receiver where the PMI indicates a choice of precoding matrix derived from a matrix multiplication of two matrices from a first code book and a second codebook. The apparatus further includes circuitry for precoding one or more layers of a data stream with the precoding matrix and transmitting the precoded layers of data stream to the remote receiver.

Transmission modes and signaling for uplink MIMO support or single TB dual-layer transmission in LTE uplink

A wireless transmission system included at least one user equipment and a base station. The base station is operable to form a downlink control information block, modulate the downlink control information, precode the modulated downlink control information, and transmit the precoded, modulated downlink control information on at least one demodulation reference signal antenna port to the at least one user equipment. The precoded, modulated downlink control information is mapped to a set of N1 physical resource block pairs in a subframe from an orthogonal frequency division multiplexing symbol T1 to and orthogonal frequency division multiplexing symbol T2.

Physical downlink control channel and physical hybrid automatic repeat request indicator channel enhancements

Embodiments of the invention are directed to a cellular communication network that can determine whether communications between one base station-UE pair may interfere with another UE that is in the same cell or a different cell. The network identifies interference parameters associated with interference signals that may be received by a UE. The interference signals may be generated by the base station itself, such as communications with other UEs, or by a neighboring base station. The base station transmits the interference parameters to the UE. The UE receives the one or more parameters comprising information about signals expected to cause intra-cell or inter-cell interference. The UE then processes received signals using the one or more parameters to suppress the intra-cell or inter-cell interference.

Network signaling for network-assisted interference cancellation and suppression

Channel state information (CSI) feedback in a wireless communication system is disclosed. User equipment transmits a CSI feedback signal via a Physical Uplink Control CHannel (PUCCH). If the UE is configured in a first feedback mode, the CSI comprises a first report jointly coding a Rank Indicator (RI) and a first precoding matrix indicator (PMI1), and a second report coding Channel Quality Indicator (CQI) and a second precoding matrix indicator (PMI2). If the UE is configured in a second feedback mode, the CSI comprises a first report coding RI, and a second report coding CQI, PMI1 and PMI2. The jointly coded RI and PMI1 employs codebook sub-sampling, and the jointly coding PMI1, PMI2 and CQI employs codebook sub-sampling.

Codebook sub-sampling for CSI feedback on PUCCH for 4TX MIMO

A satellite constellation provides communication between user terminals (UTs) and ground stations that connect to other networks. Grant-free transmissions allow the UTs access to the satellite uplink as needed. Each UT is assigned a unique preamble that represents a combination of repetition pattern (from a set of patterns) and precoding vectors (from a set of precoding vectors). The repetition pattern specifies two or more uplink slots to transmit the same data. The precoding vectors specify different phase angles for the respective uplink slots. The UT transmits a signal using the preamble, repetition pattern, and precoding vectors. The satellite receives these signals, and stores signal data representative of the signals, including repetitions. Overlapping signals from different UTs received during the same timeslot are separated using successive interference cancellation or a linear equalizer. The recovered signal may then be processed to recover data encoded therein.

System for grant-free transmissions

A transmission point (TP) comprises a processor configured to generate a transmission parameter related to a transmission property of the TP, wherein the transmission parameter comprises at least one of a transmission rank, a beamforming matrix, a transmission power, and an on/off status, and a transmitter coupled to the processor and configured to transmit the transmission parameter as part of a coordinated multi-point (CoMP) scheme. A transmission point (TP) comprises a processor configured to generate a transmission parameter related to a desired transmission property, wherein the transmission parameter comprises at least one of a transmission rank, a beamforming matrix, a transmission power, and an on/off status, and a transmitter coupled to the processor and configured to transmit the transmission parameter as part of a coordinated multi-point (CoMP) scheme.

Inter-point parameter signaling in coordinated multi-point (CoMP) networks

A method for time multiplexing subframes on a serving cell to a user equipment, wherein one set of subframes operate with the legacy LTE transmission format and one set of subframes operate with an evolved transmission format comprising reduced density CRS transmission without a PDCCH control region.

Methods for energy-efficient unicast and multicast transmission in a wireless communication system

This invention is a technique for coordinate multi-point wireless transmission between a plurality of geographically separated transmission points (TP) and at least one user equipment (UE). For coordinated multi-point communication (CoMP), UE measures the downlink wireless propagation channel corresponding to multiple geographically separated transmission points. The network configures multiple channel state indicator-reference signal (CSI-RS) resources, each of which is associated with a TP. UE measures the downlink channel using the multiple configured CSI-RS resources, and reports multiple CSIs in the uplink feedback channel. Each CSI report is defined as a “CSI-process”, where a CSI-process with a lower CSI-process-index has a higher priority. Multiple CSI-processes can be reported periodically. Each periodic CSI feedback comprises a single CSI-process. Different CSI-processes are time-domain-multiplexed on different uplink feedback time instances, and are not multiplexed in the same feedback time instance. If two CSI-processes collide in the time domain, the CSI-process of a higher priority is reported, and the CSI-process of a lower priority is dropped. The UE can also feedback multiple CSI-processes in an aperiodic manner, where multiple CSI-processes are reported simultaneously. Aperiodic feedback by the UE is triggered by an n-bit CSI-triggering field in an uplink grant transmitted by the network. Each codepoint of the n-bit triggering field triggers feedback of a subset of CSI-processes configured by the higher-layer. If a UE is configured with CoMP and without carrier aggregation (CA), CSI-processes are ordered by decreasing CSI-process priority. If a UE is configured with CoMP and carrier aggregation simultaneously, CSI-processes are ordered firstly by decreasing carrier index, and secondly by decreasing CSI-process priority.

Method and apparatus for CSI feedback in comp (coordinated multi-point) system

Channel state information (CSI) feedback in a wireless communication system is disclosed. A precoding matrix is generated for multi-antenna transmission based on precoding matrix indicator (PMI) feedback, wherein the PMI indicates a choice of precoding matrix derived from a matrix multiplication of two matrices from a first codebook and a second codebook. In one embodiment, the first codebook comprises at least a first precoding matrix constructed with a first group of adjacent Discrete-Fourier-Transform (DFT) vectors. In another embodiment, the first codebook comprises at least a second precoding matrix constructed with a second group of uniformly distributed non-adjacent DFT vectors. In yet another embodiment, the first codebook comprises at least a first precoding matrix and a second precoding matrix, where said first precoding matrix is constructed with a first group of adjacent DFT vectors, and said second precoding matrix is constructed with a second group of uniformly distributed non-adjacent DFT vectors.

4Tx codebook enhancement in LTE

A user equipment device obtains a first measurement using a first CSI-RS sub-resource and a second measurement using a second CSI-RS sub-resource. The user device derives a single CSI-process based on the first and the second measurements and reports the CSI-process to a base station. The user device receives a message from the base station configuring the first and second CSI-RS sub-resources corresponding to the single CSI-process to be reported by the user device. The message from the base station comprises a configuration of the first CSI-RS sub-resource and a separate configuration of the second CSI-RS sub-resource. The configuration of each CSI-RS sub-resource comprises, for the corresponding CSI-RS sub-resource, at least a CSI-RS sub-resource index, a periodicity, and an offset. The user device may alternatively obtain measurements using any number of CSI-RS sub-resources and then derive and report a single CSI-process based on the plurality of measurements.

Reference signal for 3D MIMO in wireless communication systems

A method of operating a time division duplex (TDD) wireless communication system is disclosed. The method includes establishing communications with a remote transceiver. A subframe configuration including static and flexible subframes is determined and transmitted to the remote transceiver. A channel state information (CSI) report is received from the remote transceiver in response to the subframe configuration.

Method and apparatus for configuration, measurement and reporting of channel state information for LTE TDD with dynamic UL/DL configuration

A method and user equipment for channel state information (CSI) reporting are described. The method receives a channel quality indicator request. The method determines a channel quality indicator based on a CSI reference resource. The method transmits a CSI report that includes the channel quality indicator via a Physical Uplink Control CHannel (PUCCH) on an uplink subframe. The CSI reference resource belongs to a subframe subset for which the CSI report is sent. The CSI reference resource includes overhead of Demodulation Reference Signals according to a corresponding rank report.

CSI reporting

A system and method for providing both localized and distributed transmission modes for EPDCCH is disclosed, where one EPDCCH comprises of one or multiple CCEs. Localized versus distributed transmission may be defined in terms of the EPDCCH to CCE resource mapping. In a localized transmission CCEs are restricted to be contained within one PRB. In a distributed transmission a CCE spans over multiple PRBs. A UE can be configured to either receive the EPDCCH only in localized or only in distributed transmissions. A UE can also be configured to expect EPDCCH transmissions in both localized and distributed transmissions. In each PRB configured by the higher layer as an EPDCCH resource, 24 REs that may be used for any DMRS transmission are always reserved and not used for EPDCCH transmission.

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Plano, TX, United States of America

Runhua Chen