Communication terminal

A communication terminal, comprising:

• communication circuitry which, in operation, performs communication through a plurality of carriers, including at least a primary carrier and a secondary carrier;
• and
• control circuitry which, in operation:
• measures reception quality of radio signals transmitted through the plurality of carriers to obtain respective measured values;
• compares the measured value of the primary carrier to a first threshold value;
• and
• compares the measured value of the secondary carrier to a second threshold value, wherein the control circuitry, in operation:
• when discontinuous reception is performed by the communication terminal, wherein periods during which the discontinuous reception is performed by the communication terminal include no data transmission and reception intervals of determined length:
• when the measured value of the primary carrier is lower than the first threshold value, performs a non-serving cell measurement for a first corresponding carrier having a same frequency as the primary carrier, of a first non-serving cell, and for a second corresponding carrier, having a same frequency as the secondary carrier, of a second non-serving cell;
• and
• when the measured value of the primary carrier is equal to or higher than the first threshold value, does not perform the non-serving cell measurement;
• and
• when discontinuous reception is not performed by the communication terminal, sends measurement results based on the measured value of the primary carrier and the measured value of the secondary carrier.