Radio communication system for reducing interferences with respect to other communication system using close frequency band

A communication control device for controlling a communication channel to be used for communications between a mobile terminal device and a second radio base station using a second frequency band which is close to a first frequency band used by a first radio base station, the communication control device comprising:

• a first distance detection unit configured to detect a first distance between the second radio base station and the first radio base station;
• a second distance detection unit configured to detect a second distance between the second radio base station and the mobile terminal device when the first distance is less than a first threshold;
• and
• a channel allocation unit configured to allocate a communication channel of a frequency far from the first frequency band in the second frequency band to the communications between the second radio base station and the mobile terminal device when the second distance is less than a second threshold.

A communication channel allocation method for allocating a communication channel to communications between one mobile terminal device and a second radio base station using a second frequency band which is close to a first frequency band used by a first radio base station, the communication channel allocation method comprising the steps of:

• controlling a received power of signals from the one mobile terminal device at the second radio base station to be constant;
• obtaining allocation rates for channels to be used for communications between the second radio base station and the one mobile terminal device according to a total number of mobile terminal devices that are carrying out communications with the second radio base station and a total received power of signals other than signals from the one mobile terminal device;
• obtaining a channel switching distance to be a criterion for switching communication channels, according to the allocation rates;
• detecting a distance between the second radio base station and the one mobile terminal device;
• and
• allocating a communication channel of a frequency far from the first frequency band in the second frequency band to the communications between the second radio base station and the mobile terminal device when the distance is greater than the channel switching distance.

A communication control device for controlling a communication channel to be used for communications between one mobile terminal device and a second radio base station using a second frequency band which is close to a first frequency band used by a first radio base station, the communication control device comprising:

• a received power control unit configured to control a received power of signals from the one mobile terminal device at the second radio base station to be constant;
• an allocation rate calculation unit configured to obtain allocation rates for channels to be used for communications between the second radio base station and the one mobile terminal device according to a total number of mobile terminal devices that are carrying out communications with the second radio base station and a total received power of signals other than signals from the one mobile terminal device;
• a distance calculation unit configured to obtain a channel switching distance to be a criterion for switching communication channels, according to the allocation rates;
• a distance detection unit configured to detect a distance between the second radio base station and the one mobile terminal device;
• and
• a channel allocation unit configured to allocate a communication channel of a frequency far from the first frequency band in the second frequency band to the communications between the second radio base station and the mobile terminal device when the distance is greater than the channel switching distance.