A mobile station comprises a radio communication unit (22) for communicating with a radio communication network for finding carriers on which transmissions are being made in active transmission intervals of a transmission cycle following a discontinuous transmission scheme. The radio communication unit is configured to select a carrier based on probability settings provided for each carrier of the scheme, scan the selected carrier during a time range that is a fraction of the transmission cycle, confirm the presence of the carrier if transmissions are detected and otherwise to adjust the probability settings of the carriers based on the timing of the scanning and the position of the carrier active transmission interval in the transmission sequence and repeat the selection of carrier based on probability settings and adjusting of probability settings until the presence of a carrier has been confirmed.