MOBILE COMMUNICATION SYSTEM AND MOBILE COMMUNICATION METHOD

摘要

A mobile communication system allows user data to be communicated directly between a plurality of radio terminals with no radio base station intervening therebetween. The communication of the user data performed directly between the plurality of radio terminals is performed by use of some of radio resources allocated to the mobile communication system. The plurality of radio terminals include a transmission side terminal that transmits the user data and a reception side terminal that receives the user data. The mobile communication system switches between a first allocation mode in which the transmission side terminal or the reception side terminal allocates radio resources to be used for communicating the user data and a second allocation mode in which the radio base station allocates the radio resources to be used for communicating the user data.