Abstract:
A method is provided for transmitting and receiving at least one of control information and a response signal at a user equipment (UE) in a carrier aggregation based wireless communication system. A first cell group having a primary cell (PCell) is configured. A second cell group having one or more secondary cells (SCells) is configured. A procedure of transmitting and receiving at least one of specific cell-related control information and a response signal is performed. If the first cell group and the second cell group are managed by a same base station, at least one of the control information and the response signal is transmitted and received on the first cell group or the second cell group. If the first cell group and the second cell group are managed by different base stations, at least one of the control information and the response signal is transmitted and received only on one of the first cell group or the second cell group according to control information type.
Abstract:
The present invention provide a method by which a terminal measures channel state information (CSI), a method by which a terminal transmits CSI, and devices for supporting the methods. A method by which a terminal feeds back CSI in a wireless access system, according to one embodiment of the present invention, can comprise the steps of: receiving an upper layer signal including a channel quality indicator (CQI) index; receiving a physical downlink control channel (PDCCH) signal including an aperiodic CSI request field; receiving a physical downlink shared channel (PDSCH) signal that is repeatedly transmitted as many time as the number indicated by the CQI index; measuring the CSI for a CSI reference resource; and feeding back the measured CSI by using a physical uplink shared channel (PUSCH) signal.
Abstract:
A method for reporting, by a UE, a downlink channel state in a wireless communication system according to an embodiment of the present invention includes: receiving a vertical precoding matrix indicator (PMI) to be used to calculate the downlink channel state; calculating a value of the downlink channel state using the received vertical PMI; and reporting the calculated downlink channel state value to an eNB, wherein the received vertical PMI is used from a later subframe between a subframe in which the vertical PMI is received and a subframe preceding a subframe in which the calculated downlink channel state value is reported by the number of subframes necessary to calculate the downlink channel state value using the received vertical PMI.
Abstract:
A method for transmitting an uplink signal at a User Equipment (UE) in a wireless communication system includes receiving, from a Base Station (BS), an uplink scheduling grant for multi-antenna transmission; transmitting the uplink signal precoded using precoding information included in the received uplink scheduling grant to the BS; and retransmitting the uplink signal to the BS according to Acknowledgment/Negative Acknowledgment (ACK/NACK) corresponding to the transmitted uplink signal. The retransmitted uplink signal is precoded using precoding information included in a most recent uplink scheduling grant or a predetermined precoding matrix if an uplink scheduling grant for the retransmission is not received from the BS.
Abstract:
The present invention provides methods for transmitting a sounding reference signal (SRS) in a wireless access system supporting a multiple connection mode, in which user equipment is connected to two or more small cells, and devices for supporting same. According to one embodiment of the present invention, the method for the user equipment transmitting the SRS in the wireless access system supporting the multiple connection mode, comprises the steps of: receiving, from a first small cell in the multiple connection mode, a control signal requesting an aperiodic SRS transmission; and confirming whether a first SRS resource region for the aperiodic SRS transmission to the first small cell and a second SRS resource region for a periodic SRS transmission to a second small cell in the multiple connection mode overlap, wherein the user equipment in the multiple connection mode maintains multiple connections with the two or more small cells, including the first small cell and the second small cell, and wherein the first small cell and the second small cell can be mutually connected through a non-ideal backhaul link.
Abstract:
The present invention relates to a method of transmitting an acknowledgement/not-acknowledgement (ACK/NACK) and a device for using such a method. According to the present invention, a cell-specific downlink-uplink setting for one of a plurality of serving cells and a reference UL-DL setting is received, an effective downlink sub-frame capable of actually receiving a data unit from one serving cell is determined based on the settings, and only an ACK/NACK for the effective downlink sub-frame is configured as a bit string and fed back.
Abstract:
The present invention relates to a wireless communication system. Particularly, the present invention relates to a method for receiving control information in a wireless communication system and a device therefor, the method comprising the steps of: receiving a PDCCH signal including uplink scheduling information; transmitting a PUSCH signal by using the uplink scheduling information: and receiving a PHICH signal including acknowledgement information on the PUSCH signal, wherein an RS for the PUSCH signal exists only in one slot per RB pair within an RB set in which the PUSCH signal is transmitted, and a resource for receiving the PHICH signal is determined by using an index of the slot in which the RS exists.
Abstract:
A method and apparatus for transmitting and receiving channel status information (CSI) for supporting 256QAM in a wireless access system are disclosed. A method for transmitting a Channel Quality Indication (CQI) index for 256QAM (Quadrature Amplitude Modulation) in a wireless access system includes: receiving, by a user equipment (UE), a message including a 256QAM indicator indicating use of a 256QAM scheme; performing channel measurement of a downlink channel through which downlink data is transmitted; and transmitting a CQI index in response to the channel measurement result to a base station (BS), wherein the UE simultaneously manages a first CQI feedback table for supporting a legacy modulation scheme and a second CQI feedback table for supporting the 256QAM scheme.
Abstract:
A method and apparatus for transmitting and receiving an MCS index for 256 QAM in a wireless access system are disclosed, which relate to methods for transmitting and receiving a Modulation and Coding Scheme (MCS) index supporting a 256 Quadrature Amplitude Modulation (QAM) scheme and apparatuses for supporting the same. The method for receiving a Modulation and Coding Scheme (MCS) index for 256 QAM (Quadrature Amplitude Modulation) in a wireless access system includes: receiving, by a user equipment (UE), a message including a 256 QAM indicator indicating use of a 256 QAM scheme; and receiving a physical downlink control channel (PDCCH) signal including the MCS index, wherein the UE obtains a modulation order and a Transport Block Size (TBS) index depending upon the MCS index for the 256 QAM scheme
Abstract:
According to various embodiments of the present disclosure, provided is a method of operating a terminal (user equipment, UE) in a wireless communication system comprising the steps of: receiving one or more synchronization signals from a base station (BS); receiving system information from the base station; receiving a radio resource control (RRC) message from the base station; receiving a first reference signal from the base station, the first reference signals being part of a plurality of first reference signals having an identical pattern, which are transmitted from the base station to a plurality of terminals including the terminal; transmitting a piece of first channel state information (CSI) associated with the first reference signal to the base station, the piece of first CSI being part of a plurality of pieces of first CSI that are transmitted from the plurality of terminals to the base station, on the basis of which a group is determined for each of the plurality of terminals from among a preset number of groups; receiving information about the group determined for the terminal from the base station; receiving a second reference signal from the base station on the basis of the information about the determined group, the second reference signal being part of a plurality of second reference signal that are transmitted from the base station to the plurality of terminals including the terminal; transmitting a piece of second CSI associated with the second reference signal to the base station, on the basis of the information about the determined group, the piece of second CSI being part of a plurality of pieces of second CSI associated with the plurality of second reference signals, which are transmitted from the plurality of terminals to the base station.