Referring to FIG. 14, each of the secondary usage nodes 40a, 40b, 40e first collects parameters to calculate coverage of each secondary system (step S11). Similarly, each of the secondary usage nodes 40c, 40d collects parameters to calculate coverage of each secondary system (step S12).

Next, each of the secondary usage nodes 40a, 40b, 40e transmits a parameter list containing collected parameters to the communication control apparatus (CM # A) 30b (step S13). Such a parameter list is received by the first communication unit 110 of the communication control apparatus (CM # A) 30b and acquired by the parameter acquisition unit 142. Similarly, each of the secondary usage nodes 40b, 40c transmits a parameter list containing collected parameters to the communication control apparatus (CM # B) 30b (step S14). Such a parameter list is received by the first communication unit 110 of the communication control apparatus (CM # B) 30b and acquired by the parameter acquisition unit 142.

Next, the calculation unit 144 of the communication control apparatus (CM # A) 30b calculates coverage of each secondary system under control using parameters acquired by the parameter acquisition unit 142 (step S21). Then, the interference control unit 146 notifies the communication control apparatus 30a of coverage information representing coverage of each secondary system calculated by the calculation unit 144 (step S25).