System and method employing algorithms and protocols for optimizing carrier sense multiple access (CSMA) protocols in wireless networks

• US 7,280,555 B2
• Filed: 09/25/2002
• Issued: 10/09/2007
• Est. Priority Date: 09/25/2001
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: MeshNetworks, Inc. (Motorola Solutions, Inc.)
• Inventors: Stanforth, Peter J., Whitehill, Eric A., Koos, Larry W.
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): O CONNOR, BRIAN T
• Application Number:
  US10/253,422
• Publication Number:
  US 20030058886A1
• Time in Patent Office: 1,840 Days
• Field of Search: 370/431, 370/445, 370/437, 370/438, 370/439, 370/447, 370/458, 370/461, 370/462, 370/468
• US Class Current: 370/445
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 28/26 Resource reservation
• CPC Class Codes: H04W 74/0816 with collision avoidance
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A system and method for achieving enhanced CSMA/CA which improves channel availability and quality of service (QoS) in a wireless communications network. The system and method establish channels to enable communication between nodes in a communication network, based on the relationship between the average time length of message data packets and the time lengths of the request to send and clear to send messages. A node of the communication network places a data packet at a location in a queue for retransmission based on a type of information contained in the data packet if the destination node for which the data packet is intended is unable to receive the data packet. The location in the queue is indicative of a duration of time that the node will delay before attempting to resend the data packet to the destination node.

Claims

1. A method for establishing channels to enable communication between nodes in a communication network, the method comprising:

determining an average length of time to transmit message data packets between a transmitting node and a destination node in said communication network;

determining a length of time to transmit a request to send message from said transmitting node to said destination node to request clearance to send a said message data packet to said destination node, and a length of time to transmit a clear to send message from said destination node to said transmitting node to indicate clearance to send said message data packet; and

establishing a quantity of data communication channels, wherein the quantity is determined by a relationship between said average length of time to transmit message data packets and said lengths of time to transmit said request to send and clear to send messages on a reservation channel.

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

said establishing establishes said quantity of data communication channels equal to an integer value determined based on a value representing said average length of time of message data packets divided by the sum of a value representing said length of time of said request to send message and a value representing said length of time of said clear to send message.

3. A method as claimed in claim 1, further comprising:

broadcasting data indicating said quantity of data communication channels to said nodes.

4. A method as claimed in claim 1, wherein:

said network includes a wireless ad-hoc communication network; and

both of said determining steps and said establishing step are performed in relation to said wireless ad-hoc communication network.

5. A system for establishing channels to enable communication between nodes in a communication network, the system comprising:

a component for determining an average length of time to transmit message data packets between a transmitting node and a destination node in said communication network; and

said component further for determining a length of time for transmitting a request to send message from said transmitting node to said destination node to request clearance to send a said message data packet to said destination node, and a length of time to transmit a clear to send message from said destination node to said transmitting node to indicate clearance to send said message data packet, and to determine a quantity of data communication channels to establish based on a relationship between said average length of time to transmit message data packets and said lengths of time to transmit each of said request to send and clear to send messages on a reservation channel.

6. A system as claimed in claim 5, wherein:

said component establishes said quantity of data communication channels equal to an integer value determined based on a value representing said average length of time for transmitting message data packets divided by the sum of a value representing said length of time to transmit said request to send message and a value representing said length of time to transmit said clear to send message.

7. A system as claimed in claim 5, wherein:

said component further broadcasts data indicating said quantity of data communication channels to said nodes.

8. A system as claimed in claim 5, wherein:

said network includes a wireless ad-hoc communication network; and

said component communicates within said wireless ad-hoc communication network.

9. A system as claimed in claim 5, wherein:

said component includes an access point of said network, adapted to provide at least some of said nodes with access to other portions of said network or another network.

10. A system as claimed in claim 5, wherein:

said component includes a mobile Internet switching center associated with said network.

11. A computer-readable medium of instructions for controlling a component for establishing channels to enable communication between nodes in a communication network, the computer-readable medium of instructions comprising:

a first set of instructions for controlling said component to determine an average length of time to transmit message data packets between a transmitting node and a destination node in said communication network;

a second set of instructions for controlling said component to determine a length of time to transmit a request to send message from said transmitting node to said destination node to request clearance to send a said message data packet to said destination node, and a length of time to transmit a clear to send message from said destination node to said transmitting node to indicate clearance to send said message data packet; and

a third set of instructions for controlling said component to determine a quantity of data communication channels to establish based on a relationship between said average length of time to transmit message data packets and each of said lengths of time to transmit said request to send and clear to send messages on a reservation channel.

12. A computer-readable medium of instructions as claimed in claim 11, wherein:

said third set of instructions controls said component to establish said quantity of data communication channels equal to an integer value determined based on a value representing said average length of time to transmit message data packets divided by the sum of a value representing said length of time to transmit said request to send message and a value representing said length of time to transmit said clear to send message.

13. A computer-readable medium of instructions as claimed in claim 11, further comprising:

a fourth set of instructions for controlling said component to broadcast data indicating said quantity of data communication channels to said nodes.

14. A computer-readable medium of instructions as claimed in claim 11, wherein:

said network includes a wireless ad-hoc communication network; and

said first, second and third set of instructions control said component which is associated with said wireless ad-hoc communication network.