A method for determining the power of signals transmitted by a radio transmission unit with several carriers over the air interface. In order to allow for a simple power detection of multicarrier signals while the air-interface is not used for data transmission, the method includes transmitting a modulated signal using a first carrier and determining its power, transmitting additionally a modulated signal using a further carrier, determining the total power of the sum of the modulated signals transmitted with the first and the further carrier, and determining the power of the modulated signal using the further carrier by subtracting the first determined power from the determined total power. The invention equally relates to a corresponding radio transmission unit and to a corresponding module for such a unit.