Patent ID: 8811287

Claim:
A method for transmitting an aperiodic sounding reference signal (SRS) at a user equipment in a wireless communication system, the method comprising: configuring parameters for the aperiodic SRS by a radio resource control (RRC) layer; receiving downlink control information (DCI) from a base station; checking carrier indication field (CIF) information of a DCI format included in the downlink control information; and transmitting the aperiodic SRS to the base station according to the CIF information, wherein the CIF information includes a triggering message of the aperiodic SRS, wherein the CIF information includes an indicator to indicate whether the parameters for the aperiodic SRS are reconfigured or not, and wherein the DCI includes information on the reconfigured parameters for the aperiodic SRS if the indicator indicates that the parameters for the aperiodic SRS are reconfigured.