Base station and control method thereof

1. A base station, which is adjacent to a macro base station and used in a cellular mobile communication system, comprising:

a radio communication unit that communicates with a radio terminal;

a control unit that performs control to switch a power consumption state of the radio communication unit on a basis of neighboring base station load information on a traffic load of the macro base station adjacent to the base station;

a network communication unit that receives the neighboring base station load information using inter-base-station communication; and

a storage unit, wherein

the control unit performs control to switch the radio communication unit from a power-off mode, in which an operation of the radio communication unit is stopped, to a low power consumption mode, in which the radio communication unit operates in a low power consumption state, on the basis of the neighboring base station load information received by the network communication unit,

the neighboring base station load information includes first neighboring base station load information newly received by the network communication unit,

the control unit performs control to switch the radio communication unit from the power-off mode to the low power consumption mode, when the first neighboring base station load information exceeds a first threshold value,

the neighboring base station load information includes second neighboring base station load information stored in the storage unit according to conditions, which is neighboring base station load information obtained in a past by the network communication unit, and

the control unit, even in a case in which the first neighboring base station load information exceeds the first threshold value, performs control such that the radio communication unit is not switched from the power-off mode to the low power consumption mode, when a difference between the first neighboring base station load information and the second neighboring base station load information under a same condition as a condition of the first neighboring base station load information is equal to or larger than a predetermined value, or when the second neighboring base station load information under the same condition as the condition of the first neighboring base station load information falls below the first threshold value.

2. A base station, which is adjacent to a macro base station and used in a cellular mobile communication system, comprising:

a radio communication unit that communicates with a radio terminal; and

a control unit that performs control to switch a power consumption state of the radio communication unit on a basis of neighboring base station load information on a traffic load of the macro base station adjacent to the base station; and

a network communication unit that receives the neighboring base station load information using inter-base-station communication, wherein

the control unit performs control to switch the power consumption state of the radio communication unit on the basis of the neighboring base station load information received by the network communication unit,

the control unit performs control to switch the radio communication unit from a low power consumption mode, in which the radio communication unit operates in a low power consumption state, to a high power consumption mode, in which the radio communication unit operates in a high power consumption state, on the basis of the neighboring base station load information,

the neighboring base station load information includes first neighboring base station load information newly received by the network communication unit, and

the control unit performs control to switch the radio communication unit from the low power consumption mode to the high power consumption mode, when the first neighboring base station load information exceeds a second threshold value.

3. The base station according to claim 2 , further comprising a storage unit, wherein

the neighboring base station load information includes second neighboring base station load information stored in the storage unit according to conditions, which is neighboring base station load information obtained in a past by the network communication unit, and

the control unit, even in a case in which the first neighboring base station load information exceeds the second threshold value, performs control such that the radio communication unit is not switched from the low power consumption mode to the high power consumption mode, when a difference between the first neighboring base station load information and the second neighboring base station load information under a same condition as a condition of the first neighboring base station load information is equal to or larger than a predetermined value, or when the second neighboring base station load information under the same condition as the condition of the first neighboring base station load information falls below the second threshold value.

4. A base station, which is adjacent to a macro base station and used in a cellular mobile communication system, comprising:

a radio communication unit that communicates with a radio terminal;

a control unit that performs control to switch a power consumption state of the radio communication unit on a basis of neighboring base station load information on a traffic load of the macro base station adjacent to the base station; and

a network communication unit that receives the neighboring base station load information using inter-base-station communication, wherein

the control unit performs control to switch the power consumption state of the radio communication unit on the basis of the neighboring base station load information received by the network communication unit,

the control unit performs control to switch the radio communication unit from a high power consumption mode, in which the radio communication unit operates in a high power consumption state, to a low power consumption mode, in which the radio communication unit operates in a low power consumption state, on the basis of the neighboring base station load information,

the neighboring base station load information includes first neighboring base station load information newly received by the network communication unit, and

the control unit performs control to switch the radio communication unit from the high power consumption mode to the low power consumption mode, when the first neighboring base station load information falls below a third threshold value.

5. The base station according to claim 4 , further comprising a storage unit, wherein

the neighboring base station load information is includes second neighboring base station load information stored in the storage unit according to conditions, which is neighboring base station load information obtained in a past by the network communication unit, and

the control unit, even in a case in which the first neighboring base station load information falls below the third threshold value, performs control such that the radio communication unit is not switched from the high power consumption mode to the low power consumption mode, when a difference between the first neighboring base station load information and the second neighboring base station load information under a same condition as a condition of the first neighboring base station load information is equal to or larger than a predetermined value, or when the second neighboring base station load information under the same condition as the condition of the first neighboring base station load information exceeds the third threshold value.

6. A base station, which is adjacent to a macro base station and used in a cellular mobile communication system, comprising:

a radio communication unit that communicates with a radio terminal; and

a control unit that performs control to switch a power consumption state of the radio communication unit on a basis of neighboring base station load information on a traffic load of the macro base station adjacent to the base station;

a network communication unit that receives the neighboring base station load information using inter-base-station communication; and

a storage unit, wherein

the control unit performs control to switch the radio communication unit from a low power consumption mode, in which the radio communication unit operates in a low power consumption state, to a power-off mode, in which an operation of the radio communication unit is stopped, on the basis of the neighboring base station load information received by the network communication unit,

the neighboring base station load information includes first neighboring base station load information newly received by the network communication unit,

the control unit performs control to switch the radio communication unit from the low power consumption mode to the power-off mode, when the first neighboring base station load information falls below a fourth threshold value,

the neighboring base station load information includes second neighboring base station load information stored in the storage unit according to conditions, which is neighboring base station load information obtained in a past by the network communication unit, and

the control unit, even in a case in which the first neighboring base station load information falls below the fourth threshold value, performs control such that the radio communication unit is not switched from the low power consumption mode to the power-off mode, when a difference between the first neighboring base station load information and the second neighboring base station load information under a same condition as a condition of the first neighboring base station load information is equal to or larger than a predetermined value, or when the second neighboring base station load information under the same condition as the condition of the first neighboring base station load information exceeds the fourth threshold value.