A wireless communications system is disclosed. The wireless communications system includes a base station unit that is provided in a predetermined area and that is configured to perform wireless communications with at least one mobile station; and at least one measurement unit that is provided in the predetermined area and that is configured to communicate with the base station unit. The measurement unit includes: a unit configured to receive at least a common control channel transmitted from the base station unit; a unit configured to measure a wireless channel status; and a unit configured to report a measurement result to the base station unit. In the wireless communications system, the base station unit adjusts a downlink wireless parameter according to the measurement result reported from the measurement unit.