Method and apparatus for performing measurement in an extension carrier

A mobile terminal configured with a plurality of component carriers in a wireless communication system, the mobile terminal comprising:

• a radio-frequency (RF) module;
• a processor;
• and
• a memory operably connectable to the processor and storing instructions that, when executed, cause the processor to perform operations comprising:
• receiving configuration information from a base station;
• and
• performing the measurement based on the received configuration information,
• wherein when the received configuration information includes an indication information for the measurement in an extension component carrier among the plurality of component carriers, the measurement in the extension component carrier is based on a channel state information reference signal (CSI-RS), and
• wherein when the received configuration information does not include the indication information for the measurement in the extension component carrier among the plurality of component carriers, the measurement in the extension component carrier is based on a cell specific reference signal (CRS).