In a multimedia broadcast/multicast service, in order to control the ratio of mobile stations capable of receiving information with high quality among mobile stations existing in a cell, a modulation section modulates a first layer code string and second layer code string heaving hierarchically different error rates into a symbol including both layer code strings, a target value storage section stores a target value corresponding to the ratio of high quality mobile stations which receive both the first layer code string and second layer code string without errors, a transmit power determining section determines to increase transmit power when the ratio of high quality mobile stations calculated by a ratio calculation section is less than a target value stored in the target value storage section and a transmit power control section increases transmit power of the modulated symbol according to the determination.