Abstract: Design of precoding and feedback for user equipment (UE)-specific reference signals (UE-RS)-based open-loop and semi-open-loop multiple input, multiple output (MIMO) systems is discussed. Aspects of the present disclosure provide for sub-resource block (RB) random precoding that allows for greater diversity gain in a lower bandwidth. In addition, the recoding may be performed using resource element (RE)-level layer shifting that provides for a number of precoders to be assigned to a number of layers for every such continuous subcarrier. As such, two codewords may experience the same effective channel quality with channel quality indicators (CQI) being averaged across all of the layers.

Abstract: Aspects of the disclosure are related to a method, apparatus, and system for using display content from a rich operating system (OS) environment as a background image in a trusted user interface (UI), comprising: capturing a display buffer of the rich OS environment; passing the captured display buffer to a Trusted Application; and displaying, with the Trusted Application, the captured display buffer as the background image in the trusted UI, wherein the Trusted Application is executed in a Trusted Execution Environment (TEE).

Abstract: Certain aspects of the present disclosure provide techniques for performing piecewise pointwise convolution, comprising: performing a first piecewise pointwise convolution on a first subset of data received via a first branch input at a piecewise pointwise convolution layer of a convolutional neural network (CNN) model; performing a second piecewise pointwise convolution on a second subset of data received via a second branch input at the piecewise pointwise convolution layer; determining a piecewise pointwise convolution output by summing a result of the first piecewise pointwise convolution and a result of the second piecewise pointwise convolution; and providing the piecewise pointwise convolution output to a second layer of the CNN model.

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: A method, a computer program product, and an apparatus for separating a cell cluster to two or more cell clusters are provided. The cell cluster may be separated into two or more cell clusters in order to mitigate interference between cells while allowing for TDD subframe configuration flexibility. The method identifies at least one separating cell in a cell cluster, the cell cluster including at least two cells having a common TDD subframe configuration, where a coupling loss between one cell in the cell cluster and at least another cell in the cell cluster is lower than a predefined threshold. The method separates the cell cluster based on the at least one separating cell into at least a first cell cluster and a second cell cluster and sets a first TDD subframe configuration for the first cell cluster and a second TDD subframe configuration for the second cell cluster.

Abstract: Design of precoding and feedback for user equipment (UE)—specific reference signals (UE-RS)—based open-loop and semi-open-loop multiple input, multiple output (MIMO) systems is discussed. Aspects of the present disclosure provide for sub-resource block (RB) random precoding that allows for greater diversity gain in a lower bandwidth. In addition, the precoding may be performed using resource element (RE)—level layer shifting that provides for a number of precoders to be assigned to a number of layers for every such continuous subcarrier. As such, two codewords may experience the same effective channel quality with channel quality indicators (CQI) being averaged across all of the layers.

Abstract: Various aspects of the disclosure relate to retransmission techniques for communication of information (e.g., for wireless communication). In some aspects, if a device's first transmission including encoded data and parity information (subject to puncture) fails, the device's retransmission (e.g., in response to a NAK) involves transmitting the parity information that was punctured. In some aspects, the coding rate used for encoding the data for the first transmission is selected to meet an error rate (e.g., a block error rate) for the second transmission. The second transmission may also include repetition information that includes the encoded data. The repetition information could also include at least a portion of the encoded parity information.

Abstract: A hybrid class B channel state information (CSI) reference signal (CSI-RS) scheme is discussed which configures one cell-common beamformed CSI-RS resource for beam tracking and another UE-specific beamformed CSI-RS resource for CSI feedback. The cell-common beamformed CSI-RS resource may be transmitted at a longer periodicity and shared by user equipments (UEs) in the cell. The beamforming may be cycled over a set of predefined weights transparent to UE. The UE-specific beamformed CSI-RS may be transmitted at a shorter periodicity and can be activated dynamically to allow resource sharing among multiple UEs. The UEs will report a CSI for the cell-common beamformed CSI-RS resource which provides a quality indicator for the associated cell-common beam and is utilized by the base station to determine the precoding weight for the UE-specific beamformed CSI-RS resource. Both resources can be configured with different parameter sets, such as number of ports, codebook type, and CSI reporting parameters.

Abstract: Polar codes may be generated with a variable block length utilizing puncturing. Some puncturing schemes consider punctured bits as unknown bits, and set the log likelihood ratio (LLR) for those bits to zero; while other puncturing schemes consider punctured bits as known bits, and set the LLR for those bits to infinity. Each of these puncturing schemes has been observed to provide benefits over the other under different circumstances, especially corresponding to different coding rates or different signal to noise ratio (SNR). According to aspects of the present disclosure, both puncturing schemes are compared, and the puncturing scheme resulting in the better performance is utilized for transmission.

Abstract: Polar codes may be generated with a variable block length utilizing puncturing. Some puncturing schemes consider punctured bits as unknown bits, and set the log likelihood ratio (LLR) for those bits to zero; while other puncturing schemes consider punctured bits as known bits, and set the LLR for those bits to infinity. Each of these puncturing schemes has been observed to provide benefits over the other under different circumstances, especially corresponding to different coding rates or different signal to noise ratio (SNR). According to aspects of the present disclosure, both puncturing schemes are compared, and the puncturing scheme resulting in the better performance is utilized for transmission.

Abstract: Aspects of the disclosure relate to wireless communication systems configured to provide techniques for polar coding control information together with combined cyclic redundancy check (CRC) information. The combined CRC information may include a number of CRC bits selected to jointly decode and verify the control information to reduce the CRC overhead.

Abstract: The present disclosure describes a method, an apparatus, and a computer readable medium for hybrid automatic repeat request (HARQ) transmissions. For example, the method may include generating a first codeword for a first information block, wherein the first codeword is a first polar code, and wherein the first information block includes cyclic redundancy check (CRC) bits; transmitting the first codeword to a receiver; determining that the first polar code is not successfully decoded at the receiver based at least on a first message received from the receiver; generating a second codeword for a second information block, wherein the second codeword is a first enhanced polar code, and wherein the second information block does not include any CRC bits; transmitting the second codeword to the receiver; and determining that the second codeword and the first codeword are successfully decoded at the receiver based at least on a second message received from the receiver.

Abstract: Various aspects of the disclosure relate to mapping different information to different sub-channels. For example, information for different users may be mapped to different Polar code sub-channels. In some aspects, the mapping may be unbalanced in that different information is mapped to different sub-channels according to the quality (e.g., in terms of error probability) of the sub-channels and a criterion associated with the information. For example, control information for users that are experiencing the worst channel quality (e.g., in a wireless communication channel) may be mapped to the Polar code sub-channels that have the best quality.

Abstract: Methods, systems, and devices for wireless communication are described. A transmitter may generate a first segmentation based on a first subset of control information and a second segmentation based on jointly encoding the first subset and a second subset of the control information. The transmitter may polar encode the first segmentation to generate a first codeword and the second segmentation to generate a second codeword, and transmit the first and second codewords. A receiver may determine a first bit sequence corresponding to the first subset based on decoding a first codeword and determine an error detection code (EDC) and a second bit sequence corresponding to the second subset based on decoding a second codeword. The receiver may perform error detection on the first and second bit sequences based on the determined EDC, and output the first bit sequence and the second bit sequence or a decoding error.

Abstract: Methods, systems, and devices for wireless communication are described. In order to exchange data over a given wireless communication network, a wireless device may first perform a cell acquisition procedure (e.g., to determine cell-specific information such as timing and frequency offsets, bandwidth, control channel formatting, etc.). In some systems, aspects of the timing information may be conveyed with scrambling codes applied to a master information block (MIB). Physical broadcast channel (PBCH) payloads, including MIB transmissions, may be jointly encoded with synchronization signal indices. Bursts of MIB transmissions may thus be decoded without blind decoding while maintaining error protection and low latency that may be necessary to obtain critical system information within the MIB.

Abstract: The disclosure relates in some aspects to information encoding. Information encoding may involve puncturing bits of a codeword or repeating bits of a codeword. The disclosure relates in some aspects to selecting a puncturing or repetition pattern. In some aspects, a puncture pattern for data encoding is selected based on a criterion that the output and the repetition input of an XOR are not erased. In some aspects, a repetition pattern for data encoding is selected based on a criterion that repetition not be applied for the output and the repetition input of an XOR.

Abstract: Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, to methods and apparatus for rate-matching control channels using polar codes. An exemplary method generally includes encoding a stream of bits using a polar code, determining a size of a circular buffer for storing the encoded stream of bits based, at least in part, on a minimum supported code rate and a control information size, and performing rate-matching on stored encoded stream of bits based, at least in part, on a mother code size, N, and a number of coded bits for transmission, E.

Abstract: Aspects of the disclosure relate to wireless communication systems configured to provide techniques for polar coding control information together with combined cyclic redundancy check (CRC) information. The combined CRC information may include a number of CRC bits selected to jointly decode and verify the control information to reduce the CRC overhead.

Abstract: In an aspect, a method of wireless communication includes transmitting first reference signals from a base station using a first set of antenna ports, and receiving first feedback information at the base station from a user equipment (UE). The first feedback information may be associated with the first reference signals. The method includes configuring a first precoder based on the first feedback information, and transmitting second reference signals to the UE based on the configuration of the first precoder. The method includes receiving second feedback information at the base station from the UE. The second feedback information may be associated with the second reference signals. The method includes configuring a second precoder based on the second feedback information.

Abstract: Aspects of the disclosure relate to wireless communication systems configured to provide techniques for multiplexing dedicated control information for a plurality of users in a single information block and polar coding the information block to produce a polar code block of dedicated control information for transmission over a wireless air interface. The information block may further include group cyclic redundancy check (CRC) information for the information block and individual CRC information for each dedicated control information.