Radio communication system, radio base station, and handover control method

摘要

A radio communication system wherein a radio terminal (200A) and a relay node (300A) are connected to a radio base station (100A), and at least one of the radio terminal (200A) and relay node (300A) can move. The radio base station (100A) controls a handover that is an operation of the radio terminal (200A) to change the connection destination thereof. The radio base station (100A) controls the handover from the radio base station (100A) to the relay node (300A) on the basis of whether a predetermined condition, which indicates that the change in relative distance between the radio terminal (200A) and the relay node (300A) is kept null or small, is satisfied or not.

主权项

1. A radio base station to which a radio terminal and a radio relay station are connected, at least one of the radio terminal and the radio relay station is movable, the radio base station comprising:
a handover controller configured to control a handover which is an operation in which the radio terminal switches a connection destination, wherein the handover controller controls the handover from the radio base station to the radio relay station based on whether or not a predetermined condition is satisfied, wherein the predetermined condition indicates that a state where a change in a relative distance between the radio terminal and the radio relay station either does not exist or is small is maintained, the predetermined condition is a condition where a first value indicating an amount of change in the relative distance over a predetermined time period is equal to or less than a threshold value, an acquisition unit configured to acquire first terminal location information indicating a location of the radio terminal at the first time; second terminal location information indicating a location of the radio terminal at the second time; first relay station location information indicating a location of the radio relay station at the first time; and second relay station location information indicating a location of the radio relay station at the second time, and a first calculator configured to calculate the first relative distance based on the first terminal location information and the first relay station location information and the second relative distance based on the second terminal location information and the second relay station location information, and to calculate a value indicating a difference between the calculated first relative distance and the calculated second relative distance as the first value.