摘要:
This specification relates to an apparatus and method for performing random access in a wireless communication system. This specification discloses a mobile station, including a reception unit for receiving TAG configuration information on which at least one serving cell configured in the mobile station is classified as a Timing Alignment Group (TAG) from a base station and a transmission unit for transmitting a random access preamble to the base station on one representative serving cell within the TAG. In accordance with this specification, a procedure of obtaining a TAV for a serving cell in order to secure and maintain uplink timing synchronization becomes clear, the time taken to obtain uplink synchronization for a serving cell may be reduced, and overhead due to excessive random access attempts may be reduced by obtaining a TAV for a plurality of serving cells through one random access procedure.
摘要:
The present invention relates to an apparatus and method for performing uplink synchronization in a multi-component carrier system. A method for performing uplink synchronization according to the present invention comprises the steps of: receiving, from a base station, a message that indicates a time alignment value for adjusting an uplink time of a sub-serving cell; adjusting the uplink time on the basis of the time alignment value; and driving a validity timer, which indicates the period of validity of the time alignment value when the sub-serving cell is deactivated. According to the present invention, with respect to a sub-serving cell, which performs a random access procedure to ensure and maintain a time alignment value, the validity of the time alignment value and whether or not uplink synchronization in the sub-serving cell is made can be quickly ascertained, and efficiency of uplink data transmission can increase.
摘要:
An apparatus and method provide a mobile station transmits power headroom information in a multiple component carrier system. The apparatus and method include receiving a mode decision parameter for deciding a mode of a Power Headroom Report (PHR) for UpLink Component Carriers (UL CCs), configured in a mobile station, from a base station, deciding the mode of the PHR based on the mode decision parameter, and transmitting the power headroom information to the base station based on the decided mode of the PHR. Accordingly, there are advantages in that limited radio resources can be efficiently used because a mobile station's overhead according to a PHR can be reduced and a base station can efficiently perform uplink scheduling and link adaptation.
摘要:
An apparatus and method for performing handover in a multiple component carrier system. In an aspect, a method of a target Base Station (BS) performing handover in a multiple component carrier system includes receiving service state information, including information about at least one candidate cell, from a source BS through a handover request message, calculating a final determination value for determining a final cell for a User Equipment (UE) which is a subject of the handover based on the service state information, selecting the final cell by comparing the final determination value and the information about the candidate cell, and sending a handover request Acknowledgement (ACK) message, including information about the selected final cell, to the source BS.
摘要:
A method of receiving a sounding reference signal (SRS) in a wireless communication system supporting multiple component carriers by a base station is provided. The method includes determining periodic SRS (P-SRS) transmission or aperiodic SRS (A-SRS) transmission about at least one serving cell (SCell) to be configured for a user equipment (UE), transmitting a triggering message including an activation or deactivation of the at least one SCell and indicating information for the A-SRS transmission according to the determination, and receiving an A-SRS from the UE through an activated SCell from among the at least one SCell configured in the UE. Uplink scheduling for an additional secondary serving cell and data communication through the uplink scheduling can be performed rapidly, as compared with a scheme using only a periodic SRS.
摘要:
An apparatus and method for activating a component carrier in a multiple component carrier system including the steps of: receiving component carrier setting information about a first uplink component carrier, which is connected with a first downlink component carrier corresponding to a secondary serving cell of a UE, from a base station; setting the first uplink component carrier on the basis of the component carrier setting information; and activating the initial state of the set first uplink component carrier according to the activation state of the first downlink component carrier. Accordingly, the ambiguity of the initial state of an uplink component carrier additionally set between the UE and the base station can be removed.
摘要:
Provided are an apparatus and a method for performing radio connection re-establishment in a multiple component carrier system. The present description discloses a terminal including: a cell selection unit which selects a cell for said radio connection re-establishment upon occurrence of failure of wireless connection; a sub-serving cell setting information constructing unit which constructs sub-serving cell setting information for specifying at least one sub-serving cell set for the terminal; a message transmitting unit which transmits a radio connection re-establishment request message for requesting procedures for the radio connection re-establishment and a radio connection re-establishment completion message indicating the completion of the procedures for the radio connection re-establishment, to a base station through the selected cell; and a message receiving unit which receives a radio connection re-establishment message as a response to said radio connection re-establishment request message.
摘要:
A method for performing handover in a multiple component carrier system includes a UE transmitting a measurement report message, including measurement values for one or more cells, to a source BS, the source BS transmitting a handover request message, including at least one of a candidate cell list including at least one candidate cell to be used in a target BS, an aggregatable cell list including at least one aggregatable cell in which UE capability is taken into consideration, and a list of sensible cells including at least one cell defined based on a similarity sensitivity of a measured frequency, to the target BS based on the measurement value, the source BS checking the cell included in the at least one list, receiving a handover ACK message including a final cell from the target BS, and determining handover, and the source BS transmitting a handover command message to the UE.
摘要:
A method for supporting activation/deactivation of serving cells by a base station (eNB) in a wireless communication system provides decreased overhead and decreased power consumption for a user equipment (UE). The method includes configuring M supportable serving cells in the UE, configuring an indicator indicating activation/deactivation of each of the M serving cells, configuring a medium access control (MAC) message which includes a MAC control element (CE) and a logical channel identifier (LCID), the MAC CE including the indicator configured for each of the M serving cells and having a length corresponding to an integer multiple of 8 bits, the LCID indicating that the MAC CE includes the indicator indicating activation/deactivation of each serving cell, and transmitting the configured MAC message to the UE. Accordingly, a control channel or data channel regarding a component carrier is selectively received depending on whether the component carrier is activated.
摘要:
Disclosed are a method and an apparatus for performing a random access by a user equipment in. The method includes transmitting a random access preamble to an evolved-NodeB (eNB) on at least one serving cell; and receiving a random access response message as a response to the random access preamble from the eNB, wherein the random access response message is transmitted through a physical downlink shared channel (PDSCH) ordered by a physical downlink control channel (PDCCH) scrambled by the at least one random access radio network temporary identifier (RA-RNTI) for the at least one serving cell, respectively. The UE can receive timing information for uplink synchronization through a plurality of serving cells to perform the uplink synchronization with the eNB and more effectively configure the random access response message transmitted from the eNB to the UE for uplink synchronization.