A method for receiving a signal by a terminal, having a plurality of cells configured, in a wireless communication system according to an embodiment of the present invention comprises the steps of: assuming a first uplink subframe of a first cell, having a time division duplex (TDD) frame structure among a plurality of cells, to be a downlink subframe on the basis of a predetermined condition and blind-decoding same; and, if a downlink grant with respect to a second cell, located in an unlicensed band among the plurality of cells, is detected by means of the blind-decoding, receiving downlink data through the second cell, wherein the first uplink subframe is indicated as an uplink subframe by means of a first uplink-downlink subframe configuration in an enhanced interface mitigation and traffic adaptation (eIMTA) fallback comprised in a system information block type 1 (SIB 1) and at the same time is indicated as a downlink subframe by means of downlink hybrid automatic repeat request (HARQ) reference configuration in the eIMTA fallback.

The present invention relates to a wireless communication system. In more detail, in relation to a method for a terminal to transmit ACK/NACK in a wireless communication system, an ACK/NACK transmission method includes: receiving at least one Physical Downlink Shared Channel (PDSCH); transmitting at least one ACK/NACK corresponding to the at least one PDSCH through a plurality of Physical Uplink Control Channel (PUCCH) formats; and, when the at least one ACK/NACK is transmitted using a first PUCCH format, transmitting at least one ACK/NACK in an antenna port transmission mode set for a second PUCCH format.

There is disclosed a method for operating a wireless device, the wireless device being Device-to-Device (D2D) enabled. The method comprises determining feedback on one or more than one communication channel comprising at least one channel of D2D communication and sending different reports on the feedback to different targets.

Systems and methods are provided for deriving channel feedback for a physical channel based on an indication of the number of transmission repetitions. In some embodiments, a method for use in a wireless device for determining channel feedback for a physical channel includes receiving control signaling including an indication of a number of transmission repetitions of the physical channel. The method also includes deriving the channel feedback for the physical channel based on the indication of the number of transmission repetitions, where a code rate corresponding to the channel feedback corresponds to an effective channel code rate of the physical channel occupying a group of physical resources including the number of transmission repetitions. In this way, the wireless device may report channel conditions that are better than the channel conditions corresponding to a single transmission, according to some embodiments.

Uplink transmission can be performed efficiently. A transmission unit that transmits performance information and/or a PUSCH of a terminal device is provided. CSI-Part2 that is multiplexed in the PUSCH is dropped until a code rate of the CSI-Part2 becomes equal to or less than a target code rate of the CSI-Part2, and the code rate of the CSI-Part2 is determined based on a calculation performance of decimal places supported in the performance information of the terminal device.

Apparatus, computer readable media, and methods are disclosed for sending feedback in a high efficiency service field. An apparatus is disclosed comprising processing circuitry configured to: decode a trigger frame from a second wireless device, wherein the trigger frame indicates a resource allocation for an uplink (UL) multi-user (MU) transmission for the first wireless device. The processing circuitry may be further configured to: determine feedback for a second wireless device based on the resource allocation. The processing circuitry may be further configured to: encode a physical layer convergence protocol (PLCP) protocol data unit (PPDU) to include a high-efficiency (HE) service field comprising the feedback in a physical (PHY) portion of the PPDU. And, the processing circuitry may be further configured to: configure the first wireless device to transmit the PPDU in accordance with the resource allocation to the second wireless device.

The present invention discloses a method, a device, and a system for transmitting uplink control information, and relates to the communications field. The method includes: encoding uplink control information to acquire a coded bit sequence of the uplink control information, where the uplink control information includes first uplink control information and second uplink control information; and transmitting the coded bit sequence of the uplink control information to a base station through a physical uplink channel. The system includes a user equipment and a base station. By encoding uplink control information to acquire a coded bit sequence of the uplink control information and transmitting, through a physical uplink channel, the coded bit sequence to a base station, the present invention supports simultaneous transmission of first uplink control information and second uplink control information and improves transmission performance.

Systems, methods, and devices for communicating short control frames are described herein. In some aspects, a method of wireless communication includes generating a control frame comprising a contention free end (CF-end) frame, the CF-end frame comprising a physical layer preamble having a type field, the type field including an indicator indicating the CF-end frame is a null data packet (NDP). The method further includes transmitting the control frame.

Some embodiments of the present disclosure provide a user equipment (UE) having active device components and passive device components. Responsive to receiving downlink (DL) transmissions in time division duplexing (TDD) mode, the active device components perform DL decoding while the passive device components perform passive transmission of ACK/NACK data. Such passive transmission may involve encoding the ACK/NACK data in an altered version of received radio frequency (RF) signals and using so-called backscatter communications to reflect the received RF signals, with alteration, using the same frequency resources used to receive the DL transmissions.

A method of physical uplink control channel (PUCCH) resource allocation to increase multiplexing capacity in enhanced licensed assisted access (eLAA) is proposed. New design of Physical Uplink Control Channel (PUCCH) is proposed. Across frequency domain of the channel bandwidth, multiple resource block repetitions are allocated for different UEs for uplink PUCCH transmission to satisfy the occupied channel bandwidth requirement for unlicensed carrier access. In addition, the resource elements of a single PUCCH resource block are partially spread into different repetitions to increase multiplexing capacity and to resource peak to average power ratio (PAPR).