Relay station and base station

A relay station capable of relaying communication between a radio communication terminal and a base station, the replay station comprising:

• a terminal communication unit which communicates with the radio communication terminal;
• a base station communication unit which communicates with the base station;
• an inside and outside determination unit which, when receiving a communication connection request from a radio communication terminal, determines whether the radio communication terminal, which has made the communication connection request, is within a predetermined area;
• and
• a call number determination unit which, when receiving a communication connection request from a radio communication terminal, determines whether the number of radio communication terminals, which are communicating with the self-station, exceeds a first predetermined number,
• wherein the terminal communication unit preferentially establishes communication with the radio communication terminal, which is determined by the inside and outside determination terminal as being within the predetermined area, and
• wherein if the number of radio communication terminals, which are communicating with the self-station, exceeds the first predetermined number, the terminal communication unit refuses establishment of communication with a radio communication terminal, which is determined as being not within the predetermined area.

A relay station capable of relaying communication between a radio communication terminal and a base station, the relay station comprising:

• a communication quality acquisition unit which, when communication between the radio communication terminal and the base station is relayed, acquires communication quality in communication between the self-station and the radio communication terminal;
• an interference determination unit which determines whether the communication between the self-station and the radio communication terminal is receiving interference based on the acquired communication quality;
• an interference notification unit which, if it is determined that the communication is receiving interference, notifies the base station of interference information informing of the interference in order to prompt handover of a radio communication terminal, which is communicating with the base station;
• a terminal communication unit which communicates with a radio communication terminal;
• a base station communication unit which communicates with the base station;
• and
• an inside and outside determination unit which when receiving a communication connection request from a radio communication terminal, determines whether the radio communication terminal, which has made the communication connection request, is within a predetermined area,
• wherein the terminal communication unit preferentially establishes communication with the radio communication terminal, which is determined by the inside and outside determination terminal as being within the predetermined area.

A base station which communicates with a relay station capable of relaying communication between the self-station and a radio communication terminal and with another radio communication terminal, the base station comprising:

• an interference reception unit which receives interference information informing that communication between the relay station and the radio communication terminal is receiving interference;
• a handover information transmission unit which, upon receiving the interference information, transmits handover information instructing another radio communication terminal, which is communicating with the self-station, to perform handover to the relay station;
• a handover performing unit which performs handover from the self-station to the relay station, in response to a handover request from the another radio communication terminal;
• and
• a carrier terminal extraction unit which, upon receiving the interference information, extracts another radio communication terminal, which is communicating with the self-station, by using a carrier wave of a frequency, which is equal or adjacent to a frequency of a carrier wave included in the interference information,
• wherein the handover performing unit transmits the handover information to the radio communication terminal extracted by the carrier terminal extraction unit.