Patent ID: 8958841
Filing Date: 2015-02-17
Classification: H04L,H04W

Abstract:
1. A method for performing uplink transmit power control at a user equipment in a wireless communication system supporting multiple carriers, the method comprising: receiving downlink control information and at least one uplink carrier indicator information from a base station, wherein the downlink control information includes an uplink transmit power control command, and wherein the at least one uplink carrier indicator information indicates an uplink carrier to which the uplink transmit power control command is applied; deciding an uplink carrier, to which the uplink transmit power control command is to be applied, based upon the at least one uplink carrier indicator information; deciding a transmit power respective to the decided uplink carrier based upon the downlink control information; and transmitting an uplink signal to the base station based upon the decided transmit power over the decided uplink carrier, wherein the at least one uplink carrier indicator information is provided either when a downlink carrier and an uplink carrier do not configure a one-to-one mapping relation, or when a cross-carrier scheduling is performed, wherein a size of a common search space in the downlink control information is determined to be 16 Control Channel Elements (CCEs), when a number of the downlink carriers is less than a predetermined value, and wherein the size of the common search space in the downlink control information is determined to be a value greater than 16 and a multiple of 4 or 8, when the number of the downlink carriers is equal to or greater than the predetermined value.