Communication Terminal, Mobile Communication System and Communication Method

• US 20090325622A1
• Filed: 09/29/2006
• Published: 12/31/2009
• Est. Priority Date: 09/29/2005
• Status: Active Grant

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Matsumura, Takashi, Miki, Tomohiro
• Granted Patent: US 8,565,840 B2
• Time in Patent Office: Days
• US Class Current: 455/522
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 52/0261 managing power supply demand, e.g. depending on battery level
• CPC Class Codes: H04W 88/04 adapted for relaying to or from another terminal or user
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communication terminal capable of receiving communication information directed to a own station from a base station even when the own station has a small battery remaining amount and cannot transmit or receive directly to/from a base station and a mobile communication system including the communication terminal and a communication method are provided.

Communication terminals (1, 2) perform wireless communication between the own station and other station and requests a base station (3) to transmit communication information obtained according to the reception state of the own station so as to perform transmission power control. When the transmission power is lower than a relay request setting value obtained from the own station battery remaining amount and the transmission power setting, a relay request is made to other station and communication information directed to the own station is received via the other station.

Claims

1. A communication terminal which is capable of performing first communication with a base station and second communication with other terminal, the communication terminal comprising:

a detection section that detects a battery remaining amount, and

a control section switchable from the first communication to the second communication according to the battery remaining amount.

2. A communication terminal in which wireless communication is mutually performed between an own station and another station and communication information directed to the own station is received via the other station, the communication terminal comprising:

a relay request section that, in a case where the own station communicates with a base station, receives relay enable information transmitted from the other station and makes a relay request for communication between the own station and the base station from the own station to the other station when a battery remaining amount of the own station is less than a predetermined threshold value.

3. The communication terminal of claim 2, further comprising:

a section that transmits identification information for the base station to identify any of the own station or the other station to the base station via the other station and receives communication information directed to the own station transmitted by the base station on a basis of the identification information of the own station via the other station.

4. The communication terminal of claim 2, further comprising:

a relay execution section that, in a case where no communication directed to the own station exists, transmits a relay enable flag from the own station to the other station if a battery remaining amount of the own station is more than a predetermined threshold value, and relays and transmits, to the other station, communication information directed to the other station transmitted by the base station on a basis of identification information of the other station when the other station requires relaying.

5. A communication terminal in which wireless communication is mutually performed between an own station and another station and a transmission request of downstream communication information directed to the own station is transmitted via the other station, the communication terminal comprising:

a relay request section that, in a case where the own station communicates with a base station, requests the other station capable of relaying to relay a transmission request of downstream communication information by a relay request of the own station if a value based on a battery remaining amount of the own station is less than a specific threshold value.

6. A communication terminal in which wireless communication is mutually performed between an own station and another station, a transmission request of downstream communication information directed to the own station is transmitted via the other station, and communication information directed to the own station is received via the other station, the communication terminal comprising:

a relay request section that requests the other station capable of relaying to relay one or both of downstream communication information directed to the own station and a transmission request of the downstream communication information directed to the own station by a relay request of the own station according to reception states of the own station and the other station and whether a battery remaining amount of the own station is less than a specific threshold value.

7. A mobile communication system comprising:

a plurality of communication terminals that perform wireless communication between an own station and another station; and

a base station that is requested to transmit downstream communication information according to a reception state of the communication terminals, wherein;

the communication terminals comprises an other-station relay request section that receives relay enable information, relay setting information, and a battery remaining amount transmitted and obtained from the other station, and requests the other station to relay communication information directed to the own station by transmitting identification information for the base station to identify any of the own station or the other station when the battery remaining amount of the other station is large, and

the base station comprises an own/other-station identification transmission section that transmits communication information of the own station to the communication terminal of the own station via the communication terminal of the other station on a basis of the identification information of the own station.

8. The mobile communication system of claim 7, wherein the base station comprises:

a scheduling section that determines a transmission sequence and a transmission amount to the communication terminal on a basis of the communication speed to a past communication amount of the communication terminal, and

a communication amount correction section that handles the communication information transmitted to the communication terminal having relayed as that transmitted to the communication terminal having requested relaying when the past communication amount of the communication terminal is computed.

9. The mobile communication system of claim 7, wherein the communication amount correction section subtracts a communication amount according to the communication information transmitted to the communication terminal having relayed from a past communication amount of the communication terminal having relayed, and adds the communication amount to a past communication amount of the communication terminal having requested relaying.

10. The mobile communication system of any one of claim 7, wherein the communication terminals mutually perform wireless communication between an own station and another station, transmit a transmission request of downstream communication information directed to the own station via the other station, and relay the transmission request of downstream communication information directed to the other station from the other station, and

wherein at least one communication terminal of the plurality of communication terminals capable of wireless communication relays and transmits a transmission request of downstream communication information directed to the plurality of communication terminals, to the base station.

11. The mobile communication system of claim 10, wherein when the at least one communication terminal is selected from the plurality of communication terminals, a terminal whose battery remaining amount is largest is selected from among the plurality of communication terminals.

12. The mobile communication system of claim 10, wherein when the at least one communication terminal is selected from the plurality of communication terminals, a communication terminal capable of relaying is randomly selected from among the plurality of communication terminals.

13. A communication method which allows first communication with a base station and second communication with other terminal, the communication method comprising:

detecting a battery remaining amount, and

switching from the first communication to the second communication according to the battery remaining amount.

14. A communication method in which wireless communication is mutually performed between an own station and other station and communication information directed to the own station is received via the other station, the communication method comprising:

receiving relay enable information transmitted from the other station when the own station communicates with a base station, and

making a relay request for communication between the own station and the base station from the own station to the other station when a battery remaining amount of the own station is less than a predetermined threshold value.

15. A communication method in which wireless communication is mutually performed between an own station and other station and a transmission request of downstream communication information directed to the own station is transmitted via the other station, the communication method comprising:

requesting the other station capable of relaying to relay a transmission request of downstream communication information by a relay request of the own station if a value based on a battery remaining amount of the own station is less than a specific threshold value when the own station communicates with a base station.