Method, program, and system for transferring data between a number of terminals that communicate via a common communication channel in a wireless network, and a wireless terminal

• US 8,203,945 B2
• Filed: 10/23/2006
• Issued: 06/19/2012
• Est. Priority Date: 10/24/2005
• Status: Active Grant

• Current Assignee: Orange S.A.
• Original Assignee: Orange S.A.
• Inventors: Gautier, Andr, Bouissou, Christian
• Primary Examiner(s): RENNER, BRANDON M
• Application Number:
  US12/083,230
• Publication Number:
  US 20090135719A1
• Time in Patent Office: 2,066 Days
• Field of Search: 370/230, 370443-445
• US Class Current: 370/230
• CPC Class Codes: H04W 48/02 Access restriction performed under specific conditions
• CPC Class Codes: H04W 74/0808 using carrier sensing, e.g. carrier sense multiple access [CSMA]
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

According to this method, each terminal is adapted to cover a coverage area. The method includes a step of sending a request-to-send data signal from a first terminal to a second terminal located in its coverage areas to advise the second terminal that the first terminal is requesting to send it data, and a step of sending a clear-to-send data signal to the first terminal to advise the first terminal that the second terminal is available to receive the data. The method further includes a step of a third terminal that has received the clear-to-send data signal and has not received the request-to-send signal sending a request-to-receive data signal to advise that it is available to receive data.

Claims

1. A method of transferring data between a plurality of terminals that communicate via a common communication channel in a wireless network, each terminal being adapted to cover a coverage area, the method including:

a step of sending a request-to-send data signal, RTS, from a first terminal to a second terminal located in a coverage area of the first terminal to advise the second terminal that the first terminal is requesting to send data;

a step of sending a clear-to-send data signal, CTS, from the second terminal to the first terminal to advise the first terminal that the second terminal is available to receive the data;

a step of receiving the clear-to-send data signal, CTS, by a third terminal in a coverage area of the second terminal, the third terminal not having received the request-to-send data signal, RTS, from the first terminal; and

upon receiving the clear-to-send data signal, a step of sending a request-to-receive data signal, RTR, from the third terminal, to advise other terminals located in a coverage area of the third terminal that the third terminal is available to receive data from one of such other terminals during transfer of data from the first terminal to the second terminal, wherein the other terminals are terminals other than the first terminal and the second terminal, and

wherein the clear-to-send data signal, CTS, specifies the intended recipient of that signal, and the request-to-receive data signal, RTR, specified specifies the identity of the third terminal but no intended recipient of that signal.

2. The data transfer method according to claim 1, including, after the step of sending the request-to-send data signal, RTS, from the first terminal, and before a step of transferring the data from the first terminal to the second terminal, a step in the first terminal of waiting for a predefined time period sufficient for the steps of sending the clear-to-send data signal, CTS, from the second terminal and sending the request-to-receive data signal, RTR, from the third terminal to be completed before the step of transferring the data.

3. The data transfer method according to claim 1, wherein at least one of the request-to-send data signal, RTS, and the request-to-receive data signal, RTR, include(s) an identifier of the terminal sending the signal.

4. The data transfer method according to claim 1, wherein at least one of the request-to-send data signal and the clear-to-send data signal include(s) an identifier of a terminal that is an intended recipient of the at least one of the request-to-send data signal and the clear-to-send data signal.

5. The data transfer method according to claim 4, wherein at least one of the request-to-send data signal, RTS, the clear-to-send data signal, CTS, and the request-to-receive data signal, RTR, include(s) information concerning a time to transfer data between the first terminal and the second terminal.

6. The data transfer method according to claim 1, wherein at least one terminal is associated with a time parameter that is decremented over time and is unable to send a signal while this parameter has a non-zero value.

7. The data transfer method according to claim 5, wherein at least one terminal is associated with a time parameter that is decremented over time and is unable to send a signal while this parameter has a non-zero value and wherein, when a terminal receives a request-to-send data signal, RTS, or a clear-to-send data signal, CTS, of which the terminal is not the intended recipient, the time parameter is incremented by a value corresponding to the information concerning the time to transfer data so as to retain a non-zero value until the first terminal has sent the data in its entirety to the second terminal.

8. The data transfer method according to claim 1, wherein the first terminal sends the request-to-send data signal, RTS, only if the data to be transferred has a volume above a predetermined threshold.

9. The data transfer method according to claim 1, wherein the request-to-receive data signal is sent by the third terminal within a predefined time period at the end of which the first terminal will be able to send the data to the second terminal in response to the clear-to-send data signal sent by the second terminal.

10. The data transfer method according to claim 1, further comprising simultaneously transferring data from the first terminal to the second terminal and data from one of the other terminals having received the request-to-receive data signal, RTR, to the third terminal.

11. The data transfer method according to claim 1, wherein the request-to-receive data signal, RTR, includes information concerning a time to transfer data between the first terminal and the second terminal in response to the clear-to-send data signal, CTS, sent by the second terminal to the first terminal.

12. The data transfer method according to claim 1, wherein the request-to-receive data signal, RTR, is sent by the third terminal after a safety time margin following the sending of the clear-to-send data signal, CTS, by the second terminal.

13. The data transfer method according to claim 1, wherein the third terminal is available to receive data from these other terminals during transfer of data from the first terminal to the second terminal.

14. The data transfer method according to claim 1, wherein the other terminals are terminals having not received any of the request-to-send data signal, RTS, from the first terminal and the clear-to-send data signal, CTS, from the second terminal.

15. A non-transitory computer-readable medium storing a data transfer program, for transferring data between a plurality of terminals that communicate via a common communication channel in a wireless network, each terminal being adapted to cover a coverage area, the program comprising:

instructions for sending a request-to-send data signal, RTS, from a first terminal to a second terminal located in a coverage area of the first terminal to advise the second terminal that the first terminal is requesting to send data;

instructions for sending a clear-to-send data signal, CTS, from the second terminal to the first terminal to advise the first terminal that the second terminal is available to receive the data;

instructions for receiving the clear-to-send data signal, CTS, by a third terminal in a coverage area of the second terminal, the third terminal not having received the request-to-send data signal, RTS, from the first terminal; and

upon receiving the clear-to-send data signal, instructions for sending a request-to-receive data signal, RTR, from the third terminal, to advise other terminals located in a coverage area of the third terminal that the third terminal is available to receive data from one of such other terminals during transfer of data from the first terminal to the second terminal, wherein the other terminals are terminals other than the first terminal and the second terminal, and

wherein the clear-to-send data signal, CTS, specifies the intended recipient of that signal, and the request-to-receive data signal, RTR, specifies the identity of the third terminal but no intended recipient of that signal.

16. A wireless terminal adapted to communicate with other wireless terminals via a common communication channel in a wireless network, incorporating the non-transitory computer-readable medium according to claim 15.

17. A system for transferring data between wireless terminals communicating via a common communication channel in a wireless network, including at least one terminal according to claim 16.