System and method for performing low-overhead, high spatial reuse medium access control in a wireless network

• US 20060072530A1
• Filed: 09/29/2005
• Published: 04/06/2006
• Est. Priority Date: 09/29/2004
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: MeshNetworks, Inc. (Motorola Solutions, Inc.)
• Inventors: Joshi, Avinash, Strutt, Guenael T.
• Granted Patent: US 7,609,670 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 99/00 Subject matter not provided for in other groups of this subclass

Abstract

A system and method for avoiding collisions between packets transmitted in a wireless network (100). A first node (102, 106 or 107) in the wireless network (100) can transmit a packet to a second node (102, 106 or 107) in the wireless network (100), such that packet includes a header that is transmitted with a higher processing gain than the data, therefore, may be received and processed by a third node (102, 106 or 107. This allows the third node (102, 106 or 107) to detect the transmission of a packet by the first node (102, 106 or 107), which can cause the third node (102, 106 or 107) to avoid transmission of a packet during the transmission by the first node (102, 106 or 107) to avoid collision between the packets. The system and method further enables the nodes (102, 106 or 107) to determine whether they can transmit to another node (102, 106 or 107) based on estimates of interference conditions that can be experienced due to the presence of other nodes (102, 106 or 107).

Claims

1. A method for communicating in a wireless network, the method comprising:

operating a node in the wireless network to provide a packet for transmission, such that a header of the packet is provided for transmission at a first processing gain and a payload of the packet is provided for transmission at a second processing gain lower than the first processing gain.

2. The method as claimed in claim 1, wherein:

the first processing gain comprises a first data rate and the second processing gain comprises a second data rate lower than the first data rate.

3. The method of claim 1, further comprising:

operating the node to select the first and second processing gains based on another node in the network, such that the first processing gain is sufficient to enable said another node to receive and process information in the packet header, or the second processing gain is high enough so that a destination node to which information in the payload is addressed is able to receive and process the information in the payload in the event that the another node is unable to receive and process the information in the packet header.

4. The method of claim 3, wherein:

the selecting step comprises operating the node to estimate interference at said another node due to the packet transmission, and to select the second processing gain based on the estimated interference.

5. The method of claim 3, further comprising:

operating said another node to control its transmission of a second packet based on the information in the packet header received when the packet is transmitted.

6. The method of claim 5, wherein said another node operating step further comprises:

operating said another node to estimate interference due to transmission of the second packet, and to transmit or refrain from transmitting the second packet based on the estimated interference.

7. The method of claim 1, further comprising:

operating the node to determine whether to transmit the packet based on an estimate of interference at other nodes in the network due to the packet transmission.

8. The method of claim 7, further comprising:

operating the node to determine whether to transmit the packet based on an estimate of interference at a receiving node for which the packet is intended.

9. The method of claim 8, further comprising:

operating the node to transmit the packet when the estimates of the interferences at the other nodes and at the receiving node are at acceptable levels.

10. A method for communicating in a wireless network, the method comprising:

transmitting a first packet from a first node to a second node;

transmitting a second packet from a third node to the second node, where transmission of the second packet begins during transmission of the first packet;

detecting a collision of the first and second packets at the second node;

monitoring transmission of the second packet at the second node to detect an end of transmission of the second packet;

transmitting a first message from the second node to the first node indicating failure of the transmission of the first packet;

transmitting a second message from the second node to the third node indicating failure of the transmission of the second; and

operating the third node, in response to receiving the second message, to wait until the first packet has been retransmitted by the first node before attempting to retransmit the second packet.

11. A method as claimed in claim 10, wherein:

the second message includes information indicating priority for retransmission of the first packet over transmission of the third packet.

12. A wireless communication network, comprising:

a first node, adapted to provide a packet for transmission, such that a header of the packet is provided for transmission at a first processing gain and a payload of the packet is provided for transmission at a second processing gain lower than the first processing gain.

13. The wireless communication network as claimed in claim 12, wherein:

the first processing gain comprises a first data rate and the second processing gain comprises a second data rate lower than the first data rate.

14. The wireless communication network of claim 12, further comprising:

at least one other node, adapted for communication in the network; and

wherein the first node is further adapted to select the first and second processing gains based on said other node in the network, such that the first processing gain is sufficient to enable said other node to receive and process information in the packet header, or the second processing gain is high enough so that a destination node to which information in the payload is addressed is able to receive and process the information in the payload in the event that the another node is unable to receive and process the information in the packet header.

15. The wireless communication network of claim 14, wherein:

the node is further adapted to estimate interference at said other node due to the packet transmission, and to select the second processing gain based on the estimated interference.

16. The wireless communication network of claim 14, further comprising:

operating the other node to control its transmission of a second packet based on the information in the packet header received when the packet is transmitted.

17. The wireless communication network of claim 16, wherein:

the other node is further adapted to estimate interference due to transmission of the second packet, and to transmit or refrain from transmitting the second packet based on the estimated interference.

18. The wireless communication network of claim 12, wherein:

the node is further adapted to determine whether to transmit the packet based on an estimate of interference at other nodes in the network due to the packet transmission.

19. The wireless communication network of claim 18, wherein:

the node is further adapted to determine whether to transmit the packet based on an estimate of interference at a receiving node for which the packet is intended.

20. The wireless communication network of claim 19, further comprising:

the node is further adapted to transmit the packet when the estimates of the interferences at the other nodes and at the receiving node are at acceptable levels.

21. A data signal embodied in a carrier wave comprising:

a header comprising data, pertaining to the data signal, for transmission at a first processing gain; and

a payload comprising data for transmission at a second processing gain lower than the first processing gain.

22. A data signal as claimed in claim 21, wherein:

the data in the header comprises information pertaining to at least one of the following;

a source of the data in the payload, a destination of the data in the payload, a data rate of the data in the payload, a length of the data signal, and type of transmission of the data signal.