RADIO COMMUNICATIONS SYSTEM

• US 20110244788A1
• Filed: 06/16/2011
• Published: 10/06/2011
• Est. Priority Date: 12/26/2008
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: OBUCHI, Kazuhisa, ODE, Takayoshi
• Granted Patent: US 9,312,928 B2
• Time in Patent Office: Days
• US Class Current: 455/7
• CPC Class Codes: H04B 7/022 Site diversity; Macro-diversity using two or more spaced independent antennas H04B7/04
• CPC Class Codes: H04L 2025/03414 Multicarrier
• CPC Class Codes: H04L 27/2607 Cyclic extensions
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01

Abstract

A radio communications system includes a radio base station, an intermediate station to receive data from the radio base station and relay the received data; and another radio base station adjacent to the radio base station. The radio base station transmits data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using a radio resource that the intermediate station uses in the relaying of the received data.

Claims

1. A radio communications system comprising:

a first radio base station;

an intermediate station to receive data from the first radio base station and relay the received data; and

a second radio base station adjacent to the first radio base station;

wherein the second radio base station comprises a transmitter to transmit data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using a radio resource that the intermediate station uses in the relaying of the received data.

2. The radio communications system according to claim 1, wherein the first radio base station also transmits data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using a radio resource that the intermediate station uses in the relaying of the received data.

3. A radio communications system comprising:

a first radio base station;

an intermediate station to receive data from the first radio base station and relay the received data; and

a second radio base station adjacent to the first radio base station;

wherein the first radio base station classifies subordinate stations into groups, and

wherein the second radio base station comprises a transmitter that transmits, to one of the groups that is to receive the data from the intermediate station, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using a radio resource that the intermediate station uses in the relaying of the received data.

4. The radio communications system according to claim 3, wherein the first radio base station transmits, to the one of the groups, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

5. The radio communications system according to claim 3, wherein:

the first radio base station classifies the stations into two groups, one group being formed from the intermediate station and mobile stations that do not use the intermediate station to perform radio communication, the other group being formed from mobile stations that use the intermediate station to perform radio communication;

the intermediate station transmits the data to the other group;

the second radio base station transmits, to the other group, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data; and

the first radio base station transmits, to the other group, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

6. A radio communications system comprising:

a first radio base station;

an intermediate station to receive data from the first radio base station and relay the received data; and

a second radio base station adjacent to the first radio base station;

wherein;

the first radio base station transmits the data in a first communication format;

the intermediate station receives the data, converts the received data from the first communication format to a second communication format, and relays the received data in the second communication format; and

the second radio base station comprises a transmitter that transmits, using the second communication format, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

7. The radio communications system according to claim 6, wherein the first radio base station also transmits data that is in the second communication format and the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

8. The radio communications system according to claim 6, wherein:

the first radio base station classifies the stations into first and second groups, the first group being formed from the intermediate station and mobile stations that do not use the intermediate station to perform radio communication, the second group being formed from mobile stations that use the intermediate station to perform radio communications;

the first radio base station transmits the data to the first group in the first communication format;

the intermediate station receives the data, converts the received data from the first communication format to the second communication format, and transmits the received data to the second group in the second communication format;

the second radio base station transmits, to the second group, data that is in the second communication format and the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data; and

the first radio base station transmits, to the second group, data that is in the second communication format and the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

9. A radio communication method comprising:

transmitting data in a first communication format, from a first radio base station to an intermediate station;

receiving, by the intermediate station, the data in the first communication format;

converting, by the intermediate station, the received data from the first communication format to a second communication format, and relaying the received data in the second communication format; and

transmitting, by a second radio base station, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the second communication format.

10. The radio communication method according to claim 9, further comprising transmitting, by the first radio base station, data that is in the second communication format and the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

11. The radio communication method according to claim 9, further comprising:

classifying, by the first radio base station, stations into first and second groups, the first group being formed from the intermediate station and mobile stations that do not use the intermediate station to perform radio communication, the second group being formed from mobile stations that use the intermediate station to perform radio communications;

transmitting, from the first radio base station to the first group, the data in the first communication format; and

transmitting, from the first radio base station to the second group, data that is in the second communication format and the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data; and

wherein;

the converting by the intermediate station converts the received data from the first communication format to the second communication format, and transmits the received data to the second group in the second communication format; and

the transmitting by the second radio base station transmits, to the second group, data that is in the second communication format and the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the received data.

12. A radio communications system comprising:

a first radio base station;

an intermediate station to receive data from the first radio base station and relay the received data; and

a second radio base station adjacent to the first radio base station;

wherein;

the first radio base station classifies stations into first and second groups, the first group being formed from the intermediate station and mobile stations that are to receive the relay data from the first radio base station, the second group being formed from mobile stations that are to receive the data via the intermediate station;

the first radio base station transmits the data to the first group;

the intermediate station receives the data, executes relaying operations on the received data, and relays the resulting data to the second group; and

the second radio base station comprises a transmitter that transmits data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using a radio resource that the intermediate station uses in the relaying of the resulting data.

13. The radio communications system according to claim 12, wherein the first radio base station transmits, to the first group, data that is the same as the data to be relayed by the intermediate station, in synchronization with the relaying by the intermediate station and by using the radio resource that the intermediate station uses in the relaying of the resulting data.

14. A radio communication method comprising:

deploying a base station that transmits a radio signal having a first communication format;

deploying an intermediate station including a monitoring unit that monitors a number of mobile stations under control of the intermediate station, and a communication format converter that performs conversion of the first communication format before relaying the radio signal, depending on a result of the monitoring; and

performing, by the communication format converter, conversion from the first communication format to a second communication format so that the radio signal is relayed in the second communication format when the monitoring unit determines that the number of mobile stations falls below a threshold.