Radio relay station and control method

Abstract

A relay node ( 200 ) transmits a terminal handover request, which requests permission for a terminal handover, or a relay station handover request, which requests permission for a relay station handover, to a radio base station ( 100 A). When the relay node receives a handover instruction which instructs a relay station handover, the relay node carries out a relay handover; and when the relay node receives a handover instruction which instructs a terminal handover, the relay node transmits the handover instruction to at least one among a group of radio terminals ( 300 E- 300 G).

1 . A radio relay station that communicates with a first radio base station as a connection destination, communicates with at least one radio terminal, and thereby relays data to be exchanged between the first radio base station and the radio terminal, comprising:
 a controller configured to:   transmit, to the first radio base station, load notification request requesting a notification of a load of a second radio base station;   control a handover of the radio terminal based on the load of the second radio base station notified by the first radio base station;   transmit, to the first radio base station, a handover request for executing the handover of the radio terminal to the second radio base station; and   instruct, to the radio terminal, the handover to the second radio base station when the radio relay station receives from the first radio base station a response message indicating that the handover request is allowed,   wherein the load notification request includes identifier of cell of the second radio base station.   
     
     
         2 . The radio relay station according to  claim 1 , wherein the handover request includes the identifier of the cell of the second radio base station. 
     
     
         3 . The radio relay station according to  claim 1 , wherein the controller further configured to control the handover of the radio terminal without changing the connection destination of the radio relay station. 
     
     
         4 . A control method of a radio relay station that communicates with a first radio base station as a connection destination, communicates with at least one radio terminal, and thereby relays data to be exchanged between the first radio base station and the radio terminal, comprising:
 transmitting, to the first radio base station, load notification request requesting a notification of a load of a second radio base station;   controlling a handover of the radio terminal based on the load of the second radio base station notified by the first radio base station;   transmitting, to the first radio base station, a handover request for executing the handover of the radio terminal to the second radio base station; and   instructing, to the radio terminal, the handover to the second radio base station when the radio relay station receives from the first radio base station a response message indicating that the handover request is allowed,   wherein the load notification request includes identifier of cell of the second radio base station.