Abstract:
The present disclosure relates to a technique for radio link monitoring in a wireless communication system, and to operation procedures of the base station and user equipment and a method for radio link quality evaluation on the basis of the technique. In the method, the user equipment divides the downlink channel bandwidth into multiple frequency ranges, measures channel states for each frequency range, and evaluates the radio link quality based on channel state measurement results. Thereafter, the user equipment sends frequency range quality information to the base station, which may then utilize the same for downlink resource allocation. Hence, it is possible to solve the problem of the existing scheme wherein the user equipment enters the physical layer problem detection state or the radio link failure state although a frequency range usable for service provisioning is present within the downlink channel bandwidth.
Abstract:
A method and an apparatus for performing random access and uplink transmission of a User Equipment (UE) supporting Carrier Aggregation (CA) are provided. The method includes determining whether a Scheduling Request (SR) is pending, determining, when the SR is pending, whether an uplink transmission resource is available in a current Transmission Time Interval (TTI), determining, when the uplink transmission resource is not available, whether a Physical Uplink Control Channel (PUCCH) resource is configured for transmission of the SR, and initiating, when the PUCCH resource is not configured, a random access process in a primary cell. The random access method and apparatus of the present invention is advantageous to reduce the waste of transmission resources.
Abstract:
Provided is a Physical Downlink Control Channel (PDCCH) transmission method of a base station for a mobile communication system based on an Orthogonal Frequency Division Multiple Access (OFDMA). The method includes acquiring downlink control information of a resource corresponding to a carrier among a plurality of carriers, identifying at least one Control Channel Element (CCE) index based on an indicator of the carrier among the plurality of carriers, generating a PDCCH for the downlink control information based on the identified CCE index, and transmitting the PDCCH through a predetermined carrier.
Abstract:
A method for activating/deactivating secondary carriers of a User Equipment (UE) in a mobile communication system supporting carrier aggregation is provided. The method comprises, receiving a control message including an activation/deactivation Control Element (CE) in a first sub-frame from a Base station, identifying an activation command or a deactivation command of at least one secondary carrier based on the control message, determining whether a current sub-frame is a second sub-frame or not, performing at least one first operation for the at least one secondary carrier in a second sub-frame, and performing, when the activation/deactivation CE indicates deactivation of the at least one secondary carrier, at least one second operation for the at least one secondary carrier no later than the second sub-frame.
Abstract:
A method and an apparatus for transmitting Hybrid Automatic Repeat reQuest (HARQ) Acknowledgement/Negative Acknowledgement (ACK/NACK) are provided. The HARQ ACK/NACK transmission method includes receiving a Physical Downlink Shared Channel (PDSCH) in a subframe of a first cell, identifying an ACK subframe for transmitting HARQ ACK/NACK corresponding to the PDSCH, and transmitting the HARQ ACK/NACK in the identified ACK subframe of a second cell.
Abstract:
A method for activating/deactivating secondary carriers of a User Equipment (UE) in a mobile communication system supporting carrier aggregation is provided. The method comprises, receiving a control message including an activation/deactivation Control Element (CE) in a first sub-frame from a Base station, identifying an activation command or a deactivation command of at least one secondary carrier based on the control message, determining whether a current sub-frame is a second sub-frame or not, performing at least one first operation for the at least one secondary carrier in a second sub-frame, and performing, when the activation/deactivation CE indicates deactivation of the at least one secondary carrier, at least one second operation for the at least one secondary carrier no later than the second sub-frame.
Abstract:
A method for activating/deactivating secondary carriers of a User Equipment (UE) in a mobile communication system supporting carrier aggregation is provided. The method comprises, receiving a control message including an activation/deactivation Control Element (CE) in a first sub-frame from a Base station, identifying an activation command or a deactivation command of at least one secondary carrier based on the control message, determining whether a current sub-frame is a second sub-frame or not, performing at least one first operation for the at least one secondary carrier in a second sub-frame, and performing, when the activation/deactivation CE indicates deactivation of the at least one secondary carrier, at least one second operation for the at least one secondary carrier no later than the second sub-frame.
Abstract:
A method and an apparatus for performing random access and uplink transmission of a User Equipment (UE) supporting Carrier Aggregation (CA) are provided. The method includes determining whether a Scheduling Request (SR) is pending, determining, when the SR is pending, whether an uplink transmission resource is available in a current Transmission Time Interval (TTI), determining, when the uplink transmission resource is not available, whether a Physical Uplink Control Channel (PUCCH) resource is configured for transmission of the SR, and initiating, when the PUCCH resource is not configured, a random access process in a primary cell. The random access method and apparatus of the present invention is advantageous to reduce the waste of transmission resources.
Abstract:
A method and apparatus of a user equipment (UE) for transmitting and receiving data in a wireless communication system. The UE receives first time division duplex (TDD) uplink-downlink configuration information for a first cell and second TDD uplink-downlink configuration information for a second cell, determines whether a subframe in the first cell is a special subframe and the subframe in the second cell is a downlink subframe according to the first and second TDD uplink-downlink configuration information, and determine, if the subframe in the first cell is the special subframe and the subframe in the second cell is the downlink subframe, not to receive a signal on the second cell in orthogonal frequency division multiplexing (OFDM) symbols that overlaps with at least one of a guard period (GP) or uplink pilot time slot in the first cell.
Abstract:
A Channel Status Information (CSI) transmission method and apparatus of a terminal are provided for use in a wireless communication system. In the wireless communication system supporting carrier aggregation, the terminal transmits the CSIs of component carriers without conflict of their transmission time points, resulting in an improvement of system performance. In a case where the transmission time points are determined to overlap unavoidably, the terminal transmits the CSI as compressed.