When DFFR is performed in a heterogeneous environment in which a pico base station coexists in the area of a macro base station and when the pico base station judges that, based on the received-signal quality report result from a mobile terminal, the macro base station causes interference to the pico base station, the pico base station reports an interference power threshold to be notified to the macro base station based on the transmission power setting value of the macro base station, the transmission power setting value of the pico base station, and the estimated interference amount calculated from the scan report result. The macro base station transmits a result of comparison between the transmission powers of multiple frequency resources and the interference power threshold, to the pico base station and the pico base station selects a frequency resource, unlikely to be affected by interference.