The present disclosure relates to a method and an apparatus for transmitting a control channel in an intra-cell carrier aggregation system. The method includes establishing a connection with a base station through a Primary cell (Pcell) of a Time Division Duplex (TDD) scheme and a Secondary cell (Scell) of a Frequency Division Duplex (FDD) scheme. The method also includes receiving data through the Scell before a timing configured as an uplink sub-frame according to a TDD UpLink-DownLink (UL-DL) configuration of the Pcell. The method also includes transmitting a feedback of the received data through the Pcell in a feedback sub-frame. By the method, a feedback for a data can be effectively transferred.

In one embodiment, a TDD repeater system comprises: a master unit comprising separate uplink and downlink signal paths defined therein, and configured to couple in an uplink direction to a base station and in a downlink direction to at least one remote antenna unit, wherein the uplink path communicates uplink communication signals, wherein the downlink path communicates downlink communication signals; a switch configured to change direction of signal transmissions within the master unit between the uplink communication signals and the downlink communication signals; a synchronizing unit is configured to receive via the downlink signal path a clock signal from the downlink communication signals, wherein the synchronizing unit supplies a control signal to the switch corresponding to the clock signal; wherein the switch swaps the direction of signal transmissions within the master unit between the uplink communication signals and the downlink communication signals in response to the control signal.

Disclosed are various embodiments for a system and method of measuring and characterizing a PLC communication network comprising transmitting a plurality of packets from a PLC master device to a PLC terminal device via a PLC communication network, measuring a plurality of round-trip time (RTT) timestamps for the plurality of packets in the PLC master device, determining an observed probability density function based on the plurality of RTT timestamps, approximating a plurality of probability density functions, determining a rating for the probability density functions based on a comparison of the probability density functions to the observed probability density function, characterizing the PLC communication network based on the ratings of the plurality of probability density functions, and scheduling subsequent transmissions based on the characterization of the PLC Communication network.

The present disclosure relates to a method and an apparatus for transmitting a control channel in an intra-cell carrier aggregation system. The method includes establishing a connection with a base station through a Primary cell (Pcell) of a Time Division Duplex (TDD) scheme and a Secondary cell (Scell) of a Frequency Division Duplex (FDD) scheme. The method also includes receiving data through the Scell before a timing configured as an uplink sub-frame according to a TDD UpLink-DownLink (UL-DL) configuration of the Pcell. The method also includes transmitting a feedback of the received data through the Pcell in a feedback sub-frame. By the method, a feedback for a data can be effectively transferred.

A method and apparatus for transmitting control information in a wireless communication system supporting carrier aggregation (CA) is disclosed. A method for transmitting control information to a base station (BS) by a user equipment (UE) in a wireless communication system includes receiving at least one of a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) from the base station through at least one serving cell configured in the user equipment, and transmitting control information regarding PDCCH reception or PDSCH reception indicated by the PDCCH to the base station. The control information is transmitted through a physical uplink control channel (PUCCH) of a primary cell, using control information feedback timing of at least one of the primary cell and a first cell of the at least one serving cell, and the at least one serving cell uses different uplink and downlink (UL-DL) configurations.

Exemplary methods for coordinating inter-cell interference in a heterogeneous network comprising a macro cell and at least one small cell include obtaining, with regard to a terminal device in a small cell, a type of interference from the macro cell to the small cell, and determining a relationship between a number of uplink subframes and a number of downlink subframes in a current subframe configuration used in the macro cell. The methods also include allocating protected subframes for the terminal device according to the obtained type of interference and the determined relationship, and scheduling transmission in relation to the allocated protected subframes in the macro cell.

A method and apparatus for transmitting ACK/NACK information in a wireless communication system are disclosed. In accordance with a method for transmitting ACK/NACK information, an ACK/NACK signal of downlink transmission in a downlink subframe set is transmitted in a single uplink subframe. In this case, if a first physical uplink control channel (PUCCH) format is established by a higher layer for a downlink receiver, and if one physical downlink shared channel (PDSCH) is transmitted in a downlink subframe set, the ACK/NACK information can be transmitted using a second PUCCH format on PUCCH resources established by a higher layer for the second PUCCH format.

A system and method of subframe configuration in licensed-assisted access using long-term evolution (LAA-LTE) with carrier aggregation (CA). A wireless device such as an eNodeB (eNB) may transmit control information in a subframe from a secondary cell (SCell) in downlink control information (DCI) to a user equipment (UE). The SCell may operate in an unlicensed band. The control information may indicate at least one of a non-ending subframe in a data burst, an ending subframe, and a duration of the ending subframe. The duration may be one of a predefined number of orthogonal frequency-division multiplexing (OFDM) symbol durations, and the ending subframe may be a partial or full subframe. A partial ending subframe may use a time slot structure in a time division duplexing (TDD) scheme, e.g., downlink pilot time slots (DwPTS). The eNB may then transmit to the UE data in the subframe according to the control information.

The present invention is designed to improve throughput when CA is executed between multiple cells including a TDD cell. A user terminal carries out radio communication with a plurality of cells by employing carrier aggregation, and has a receiving section that, when a connection is established with a TDD cell, receives information about a predetermined DL/UL configuration that is selected from a plurality of DL/UL configurations, and a control section that controls transmission and reception to and from the TDD cell based on the predetermined DL/UL configuration received, and a DL/UL configuration to carry out DL communication in all subframes is included as one in the plurality of DL/UL configurations, and the control section uses the DL/UL configuration to carry out DL communication in all subframes as one of the DL/UL configurations only when the connecting TDD cell is a secondary cell.

The present disclosure relates to a method and an apparatus for transmitting a control channel in an intra-cell carrier aggregation system. The method includes establishing a connection with a base station through a Primary cell (Pcell) of a Time Division Duplex (TDD) scheme and a Secondary cell (Scell) of a Frequency Division Duplex (FDD) scheme. The method also includes receiving data through the Scell before a timing configured as an uplink sub-frame according to a TDD UpLink-DownLink (UL-DL) configuration of the Pcell. The method also includes transmitting a feedback of the received data through the Pcell in a feedback sub-frame. By the method, a feedback for a data can be effectively transferred.