In the mobile terminal, the reception quality estimating unit measures a
reception quality, and at least one of the data buffer monitoring unit
and the transmission power monitoring unit measures a data transmission
capability. Based on the measured reception quality and data transmission
capability, the terminal determines a transmission mode to be used, and
reports it to the base station. The base station determines the
transmission mode to be practically used in accordance with the reported
transmission mode, and notifies it to the mobile terminal. The base
station transmits data according to the determined transmission mode, and
the mobile terminal receives data according to the notified transmission
mode. Thereby, the radio communication system determines the transmission
mode in consideration for not only the reception quality, but also the
deficiency in the data transmission capability of the terminal.