A radio communications system comprising a backbone network, radio stations connected to the backbone network by using a wired transmission line or by using radio transmission, a network connecting radio station (10, 50) and a counterparty radio station (20, 60), the network connecting radio station being one of the radio stations connected to the backbone network and the counterparty radio station being in radio communications with the network connecting radio station, wherein the network connecting radio station includes an information obtaining unit (101, 501) configured to obtain first information indicating a radio communications condition of one or more surrounding radio stations surrounding the network connecting radio station from the one or more surrounding radio stations connected to the backbone network, the first information indicating the radio communications condition of the radio station including information on a frequency used by the radio station and information on a waveform feature amount which information exhibits a periodic steadiness of a signal waveform as a statistical characteristic of the signal waveform transmitted by the radio station; an information reporting unit configured to report, to the counterparty radio station, all or some of the first information indicating a radio communications condition obtained from the surrounding radio station; and a radio resource parameter determining unit configured to determine, based on the information indicating the radio communications condition of the surrounding radio station, second information indicating a measured value of the waveform feature amount that is reported from the counterparty radio station, and information on reliability, whether communications can be conducted between the network connecting radio station and the counterparty radio station, and a radio resource parameter to be used when the communications are permitted, wherein the counterparty radio station includes: a waveform information extracting unit configured to calculate, based on each of one or more waveform feature amounts included in the first information reported from the network connecting radio station, the measured value of the waveform feature amount of a signal received from another of the radio stations; a reliability determining unit configured to demodulate a signal received from the surrounding radio station and to determine the reliability of the demodulating; and a received status reporting unit configured to report, to the network connecting radio station, the second information indicating the measured value of the waveform feature amount calculated at the waveform information extracting unit and information indicating the reliability determined at the reliability determining unit. a waveform information extracting unit configured to calculate, based on each of one or more waveform feature amounts included in the first information reported from the network connecting radio station, the measured value of the waveform feature amount of a signal received from another of the radio stations; a reliability determining unit configured to demodulate a signal received from the surrounding radio station and to determine the reliability of the demodulating; and a received status reporting unit configured to report, to the network connecting radio station, the second information indicating the measured value of the waveform feature amount calculated at the waveform information extracting unit and information indicating the reliability determined at the reliability determining unit.