A method for cooperative communications among base stations according to the present invention includes: a first step in which a serving base station determines whether a user device is in an mode of cooperative communications among the base stations; a second step in which the serving base station uses a downlink control signal to make configuration for the user device; a third step in which the user device obtains (i) system information regarding the serving base station and a cooperative communication base station indicated by configuration information received and (ii) channel state information; a fourth step in which the user device feeds back channel state information regarding downlink channels between the user device and the serving base station and between the user device and the cooperative communication base station; a fifth step in which the serving base station carries out resource scheduling and backhaul communications in accordance with the channel state information thus fed back; and a sixth step in which the user device receives an allocation instruction to allocate downlink resources.