Handover performed in consideration of uplink/downlink component carrier setup

Patent metadata

Field	Value
Publication number	US-2016227451-A1
Application number	US-201615096054-A
Country	US
Kind code	A1
Filing date	Apr 11, 2016
Priority date	Mar 13, 2009
Publication date	Aug 4, 2016
Grant date	—

Abstract

The present invention relates to a wireless communication system which supports carrier aggregation. More particularly, the present invention relates to a method and to an apparatus for enabling a user equipment to perform a handover in a wireless communication system which supports carrier aggregation. The method for performing a handover comprises the steps of: transmitting a measurement report on a target cell to a serving cell; receiving, from the serving cell, a message containing a signature route sequence index, cyclic shift parameters, and information related to the component carrier of the target cell; confirming contention-based signatures generated on the basis of the signature route sequence index and cyclic shift parameters; and transmitting one of said contention-based signatures to the target cell for random access, via one or more component carriers, on the basis of said information related to the component carrier. The present invention also relates to an apparatus for the method.

First claim

1 . A method for performing a handover at a user equipment (UE) in a wireless mobile communication system, the method comprising:
receiving, by the UE from a source base station, a handover command message, wherein the handover command message contains allocation information of a plurality of Downlink Component Carriers (DL CCs) and a plurality of Uplink CCs (UL CCs), and wherein the plurality of DL CCs consist of a primary DL CC and one or more non-primary DL CC(s); and transmitting, by the UE to a target base station, a random access preamble via a UL CC corresponding to the primary DL CC among the plurality of UL CCs.

2 . The method of claim 1 , further comprising: transmitting, by the UE to the source base station, a measurement report for the target base station, before a receipt of the handover command message.

3 . The method of claim 2 , wherein each of the plurality of UL CCs corresponds to a respective DL CC.

4 . The method of claim 1 , wherein the plurality of DL CCs and the plurality of UL CCs are assigned by the target base station.

5 . The method of claim 1 , wherein each of the plurality of DL CCs and the plurality of UL CCs has a respective center carrier.

6 . A user equipment comprising:
an RF (Radio Frequency) device; and a processor operatively connected to the RF device and configured to: receive, from a source base station, a handover command message, wherein the handover command message contains allocation information of a plurality of Downlink Component Carriers (DL CCs) and a plurality of Uplink CCs (UL CCs), and wherein the plurality of DL CCs consist of a primary DL CC and one or more non-primary DL CC(s), and transmit, to a target base station, a random access preamble via a UL CC corresponding to the primary DL CC among the plurality of UL CCs.

7 . The user equipment of claim 6 , wherein the process is further configured to transmit, by the UE to the source base station, a measurement report for the target base station, before a receipt of the handover command message.

8 . The user equipment of claim 7 , wherein each of the plurality of UL CCs corresponds to a respective DL CC

9 . The user equipment of claim 6 , wherein the plurality of DL CCs and the plurality of UL CCs are assigned by the target base station.

10 . The user equipment of claim 6 , wherein each of the plurality of DL CCs and the plurality of UL CCs has a respective center carrier.

Assignees

• Lg Electronics Inc

Inventors

• Chung Jae Hoon
• Kwon Yeong Hyeon
• Han Seung Hee
• Kim So Yeon

Classifications

• H04J11/0093 Primary

  Neighbour cell search · CPC title

• H04L5/001

  the frequencies being arranged in component carriers · CPC title

• H04W36/0077

  of access information of target access point · CPC title

• H04L5/0007

  the frequencies being orthogonal, e.g. OFDM(A) or DMT · CPC title

• H04L5/0094

  Indication of how sub-channels of the path are allocated · CPC title