Frequency management apparatus and frequency management method in wireless system

A frequency management method for managing frequency use by radio stations in a wireless system that shares a frequency allocated to another wireless system, comprising:

• by a frequency use reception section, receiving a notice regarding a change in state of frequency use from a radio station managed by a relevant frequency management apparatus;
• and
• by an acceptable transmit power setting section, setting acceptable transmit power for at least one radio station managed by another frequency management apparatus different from the frequency management apparatus, based on the notified change in state of frequency use.

A radio station in a wireless system that shares a frequency allocated to another wireless system, comprising:

• a section for sending a notice regarding a change in state of frequency use to a first frequency management apparatus that manages this radio station;
• and
• a section for setting acceptable transmit power based on a set value of acceptable transmit power received directly from a second frequency management apparatus different from the first frequency management apparatus, or from the second frequency management apparatus via the first frequency management apparatus.