Apparatus and method for performing uplink synchronization in wireless communication system
First Claim
1. A user equipment (UE) performing an uplink synchronization in a wireless communication system, the UE comprising:
- a receiving unit configured for receiving a medium access control (MAC) protocol data unit (PDU) from a base station (BS); and
a MAC processing unit configured for;
identifying that the MAC PDU includes a MAC header and a MAC control element (CE);
obtaining, from the MAC header, a subheader;
obtaining, from the subheader, a logical channel identifier (LCID) indicating an index to identify whether the MAC CE is for timing advance command (TAC);
obtaining, from the MAC CE, a TAC field with 6 bits indicating a timing alignment value (TAV) and a timing alignment group (TAG) index field with 2 bits identifying a TAG to control uplink timing adjustment identically with the TAV;
identifying the TAG to which the TAV is applied based on the TAG index field; and
controlling the uplink timing adjustment for at least one serving cell in the identified TAG.
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Accused Products
Abstract
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.
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Citations
20 Claims
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1. A user equipment (UE) performing an uplink synchronization in a wireless communication system, the UE comprising:
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a receiving unit configured for receiving a medium access control (MAC) protocol data unit (PDU) from a base station (BS); and a MAC processing unit configured for; identifying that the MAC PDU includes a MAC header and a MAC control element (CE); obtaining, from the MAC header, a subheader; obtaining, from the subheader, a logical channel identifier (LCID) indicating an index to identify whether the MAC CE is for timing advance command (TAC); obtaining, from the MAC CE, a TAC field with 6 bits indicating a timing alignment value (TAV) and a timing alignment group (TAG) index field with 2 bits identifying a TAG to control uplink timing adjustment identically with the TAV; identifying the TAG to which the TAV is applied based on the TAG index field; and controlling the uplink timing adjustment for at least one serving cell in the identified TAG. - View Dependent Claims (2, 3, 4, 5)
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6. A method of performing an uplink synchronization by a user equipment (UE) in a wireless communication system, the method comprising:
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receiving a medium access control (MAC) protocol data unit (PDU) from a base station (BS); identifying that the MAC PDU includes a MAC header and a MAC control element (CE); obtaining, from the MAC header, a subheader; obtaining, from the subheader, a logical channel identifier (LCID) indicating an index to identify whether the MAC CE is for timing advance command (TAC); obtaining, from the MAC CE, a TAC field with 6 bits indicating a timing alignment value (TAV) and a timing alignment group (TAG) index field with 2 bits identifying a TAG to control uplink timing adjustment identically with the TAV; identifying the TAG to which the TAV is applied based on the TAG index field; and controlling the uplink timing adjustment for at least one serving cell in the identified TAG. - View Dependent Claims (7, 8, 9, 10)
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11. A base station (BS) performing an uplink synchronization in a wireless communication system, the BS comprising:
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a medium access control (MAC) processing unit configured for; generating a timing advance command (TAC) field with 6 bits indicating a timing alignment value (TAV) and a timing alignment group (TAG) index field with 2 bits identifying a TAG to control uplink timing adjustment identically with the TAV; generating a MAC control element (CE) by including the TAC field and the TAG index field in the MAC CE; setting a logical channel identifier (LCID) indicating an index to identify whether the MAC CE is for TAC; generating a header by including a subheader with the LCID in the header; and generating a MAC protocol data unit (PDU) comprising the header and the MAC CE; and a transmitting unit configured for transmitting the MAC PDU to a user equipment (UE). - View Dependent Claims (12, 13, 14, 15)
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16. A method of performing an uplink synchronization by a base station (BS) in a wireless communication system, the method comprising:
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generating a timing advance command (TAC) field with 6 bits indicating a timing alignment value (TAV) and a timing alignment group (TAG) index field with 2 bits identifying a TAG to control uplink timing adjustment identically with the TAV; generating a MAC control element (CE) by including the TAC field and the TAG index field in the MAC CE; setting a logical channel identifier (LCID) indicating an index to identify whether the MAC CE is for TAC; generating a header by including a subheader with the LCID in the header; generating a MAC protocol data unit (PDU) comprising the header and the MAC CE; and transmitting the MAC PDU to a user equipment (UE). - View Dependent Claims (17, 18, 19, 20)
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Specification