On the basis of a spreading factor obtained by despreading a control channel of received data by a control channel despreading unit, a spreading factor determination unit determines a transmission rate of the received data. User data subjected to despreading processing at a user data despreading unit is demodulated by a demodulator and temporarily stored in a demodulated data memory. The user data read from the demodulated data memory is decoded by a decoder, whereas the result of decoding by the decoder is supplied to a delay measurement unit, where a delay time relative to the above processing, of the user data is detected. A channel resource management unit manages the number of available resources at all times or in a constant cycle on the basis of transmission rates of respective radio channels detected by the spreading factor determination unit and delay processing times of the respective radio channels detected by the delay measurement unit.