A method of controlling a mobile communication terminal including a first antenna and a second antenna is provided. The method includes receiving transmission data to be transmitted, applying first power smaller than a first threshold value to the first antenna, applying second power smaller than the first threshold value to the second antenna, and cooperatively transmitting the transmission data based on the first power and the second power, respectively, by the first antenna and the second antenna, wherein a sum of the first power and the second power is larger than a second threshold value.