Suppression of interferences between cells

1. A mobile communication system using FDMA for an uplink and comprising:

a radio base station;

a neighboring base station that neighbors the base station; and

user equipment;

wherein the same frequency for the uplink is used between the radio base station and the neighboring base station, and a time-slot and a frequency to be transmitted by each unit of the user equipment are changed for each unit of the user equipment to multiplex a plurality of user signals,

wherein the radio base station includes a first circuit that measures an interference power in a cell that belongs to the radio base station, and a second circuit that transmits to the neighboring base station interference information that includes frequency information in which the interference power is measured, wherein the measured interference power at least relates to the neighboring base station;

wherein the neighboring base station includes a third circuit that receives the interference information from the radio base station, and a fourth circuit that checks a correlativity between the frequency and the time-slot of the interference information and that of a signal received from the user equipment and that performs scheduling, for a unit of user equipment in a cell that belongs to the neighboring base station, the scheduling specifying a time-slot and a frequency; and

wherein the user equipment includes a fifth circuit that transmits an uplink user signal in accordance with the time-slot and frequency that are specified by the scheduling.

2. The mobile communication system according to claim 1 , wherein the interference information further includes time-slot information of the measured interference power.

3. The mobile communication system according to claim 1 , wherein the neighboring base station further includes a sixth circuit that instructs a unit of user equipment in a cell that belongs to the neighboring base station to reduce a transmission power in response to the interference information received from the radio base station.

4. In a mobile communication system using FDMA for an uplink and comprising: a radio base station; a neighboring base station that neighbors the base station; and user equipment, wherein the same frequency for the uplink is used between the radio base station and the neighboring base station, and a time-slot and a frequency to be transmitted by each of unit of the user equipment are changed for each unit of the user equipment to multiplex a plurality of user signals, the radio base station comprising:

a first circuit that measures an interference power in a cell that belongs to the radio base station; and

a second circuit that transmits to the neighboring base station interference information that includes frequency information in which the interference power is measured, wherein the measured interference power at least relates to the neighboring base station,

wherein the neighboring base station includes a third circuit that receives the interference information from the radio base station, and a fourth circuit that checks a correlativity between the frequency and the time-slot of the interference information and that of a signal received from the user equipment and that performs scheduling, for a unit of user equipment in a cell that belongs to the neighboring base station, the scheduling specifying a time-slot and a frequency.

5. The radio base station according to claim 4 , wherein the interference information further includes time-slot information of the measured interference power.

6. The radio base station according to claim 4 , further comprising a third circuit that instructs a unit of user equipment in a cell that belongs to the base station to reduce a transmission power in response to the interference information received from the neighboring radio base station.

7. In a mobile communication system using FDMA for an uplink and comprising: a radio base station; a neighboring base station that neighbors the base station; and user equipment, wherein the same frequency for the uplink is used between the radio base station and the neighboring base station, and a time-slot and a frequency to be transmitted by each unit of the user equipment are changed for each unit of the user equipment to multiplex a plurality of user signals, the user equipment comprising:

a first circuit that communicates with the neighboring base station that receives, from the radio base station that measures an interference power in a cell that belongs to the radio base station, the interference information including frequency information in which the interference power is measured, wherein the measured interference power at least relates to the neighboring base station; and

a second circuit that transmits an uplink user signal in accordance with the time-slot and frequency that are specified by a scheduling based on the received interference information in the neighboring base station,

wherein the neighboring base station includes a third circuit that receives the interference information from the radio base station, and a fourth circuit that checks a correlativity between the frequency and the time-slot of the interference information and that of a signal received from the user equipment and that performs scheduling, for a unit of user equipment in a cell that belongs to the neighboring base station, the scheduling specifying a time-slot and a frequency.

8. The user equipment according to claim 7 , wherein the interference information further includes time-slot information of the measured interference power.

9. The user equipment according to claim 7 , further comprising a third circuit that reduces a transmission power in accordance with an instruction to reduce a transmission power that is issued by the neighboring station in response to the interference information received from the radio base station.

10. A method of suppressing interferences between cells in a mobile communication system using FDMA for an uplink and comprising: a radio base station; a neighboring base station that neighbors the base station; and user equipment, wherein the same frequency for the uplink is used between the radio base station and the neighboring base station, and a time-slot and a frequency to be transmitted by each unit of the user equipment are changed for each unit of the user equipment to multiplex a plurality of user signals, the method comprising the steps of

measuring, by the radio base station, an interference power in a cell that belongs to the radio base station;

transmitting, by the radio base station, to the neighboring base station interference information that includes frequency information in which the interference power is measured, wherein the measured interference power at least relates to the neighboring base station;

receiving, by the neighboring base station, the interference information from the radio base station, and

checking, by the neighboring base station, a correlativity between the frequency and the time-slot of the interference information and that of a signal received from the user equipment.

11. The method according to claim 10 , wherein the interference information further includes time-slot information of the measured interference power.

12. The method according to claim 10 , further comprising the step of instructing, by the neighboring base station, a unit of user equipment in a cell that belongs to the neighboring base station to reduce a transmission power in response to the interference information received from the radio base station.