A base station is connected to a first user terminal in a mobile communication system that performs spatial multiplexing transmission for the first user terminal and a second user terminal by applying a same radio resource and a same precoder matrix. The base station comprises: a control unit that notifies another base station connected to the second user terminal of a first statistic for each piece of first precoder matrix information fed back from the first user terminal and a second statistic for each downlink radio resource in the first user terminal.