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 Network

• US 20090135719A1
• Filed: 10/23/2006
• Published: 05/28/2009
• Est. Priority Date: 10/24/2005
• Status: Active Grant

• Current Assignee: Orange S.A.
• Original Assignee: Orange S.A.
• Inventors: Gautier, Andre, Bouissou, Christian
• Granted Patent: US 8,203,945 B2
• Time in Patent Office: Days
• 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 its coverage area 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;

a step of a third terminal that has received the clear-to-send data signal (CTS) and has not received the request-to-send data signal (RTS) sending a request-to-receive data signal (RTR) to advise that the third terminal is available to receive data.

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

3. The data transfer method according to claim 1, wherein the request-to-send data signal (RTS) and/or 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 the request-to-send data signal and/or the clear-to-send data signal include(s) an identifier of the terminal that is the intended recipient of the signal.

5. The data transfer method according to claim 1, wherein the request-to-receive data signal (RTS) and/or the clear-to-send data signal (CTS) and/or the request-to-receive data signal (RTR) include(s) information concerning the 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 4, 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 it is not the intended recipient, its 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, for example more than 500 bytes.

9. A data transfer program for a wireless terminal including software instructions for:

sending a request-to-send data signal (RTS) to advise another terminal of the intention to send it data (D1); and

sending a clear-to-send data signal (CTS) to advise another terminal that has sent it a request-to-send data signal (RTS) that it is available to receive data;

when the wireless terminal has received a clear-to-send data signal (CTS) and has not received a request-to-send signal (RTS), sending a request-to-receive data signal (RTR) to advise that the terminal is available to receive data.

10. A wireless terminal adapted to communicate with other wireless terminals via a common communication channel in a wireless network, incorporating a data transfer program according to claim 9.

11. 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 10.