Granted Patent B2

US 8,532,023 · App. 11/772,140 · Granted Sep 10, 2013

Abstract

Claims (68)

1. A method adapted for use in a node of a wireless mesh network comprising a plurality of nodes, the method comprising:

determining, for each of a plurality of links supporting any of a plurality of data transmission paths, a long term link quality (LTLQ) parameter;

determining, for each of said plurality of links, an interference aware routing metric (iAWARE) parameter associated with any respective proximate links;

adapting the LTLQ parameter of each of said plurality of links according to the respective iAWARE parameter to determine thereby a link quality parameter; and

routing data according to said link quality parameter.

2. The method of claim 1 , wherein said LTLQ parameter comprises an Expected Transmission Count (ETX) parameter.

3. The method of claim 1 , wherein said LTLQ parameter comprises an Expected Transmission Time (ETT) parameter.

4. The method of claim 1 , wherein said step of adapting comprises scaling said LTLQ parameter using said respective iAWARE parameter.

5. The method of claim 1 , further comprising:

determining, for each of said plurality of data paths, a sum of the quality parameters of the links forming the data path; and

selecting the data path having a most favorable sum of quality parameters.

6. The method of claim 5 , further comprising:

updating a routing table according to the selected data path.

7. The method of claim 1 , further comprising:

selecting a least interfering channel for routing data to a next network node.

8. The method of claim 1 , wherein said iAWARE parameter is calculated according to the following equation:

iAWARE

j

=

ETTj

IR

j

where

ETT J is the Expected Transmission Time;

IR J is the interference ratio for a node.

9. The method of claim 2 , wherein said ETX parameter is determined using a forward delivery ratio d_f and a reverse delivery ratio d_r for each link, the forward delivery ratio d_f comprising a measured probability that a data packet successfully arrives at the recipient node, the reverse delivery ratio d_r comprising a measured probability that an ACK packet is successfully received from the recipient node.

10. The method of claim 2 , wherein said ETT parameter is calculated according to the following equation:

ETT

i

=

ETX

i

×

S

B

i

where S is the packet size used, and B, is the raw data rate of the link i, and ETX i is an expected MAC transmission time of a packet of size S over the link i.

11. The method of claim 1 , wherein each node within the wireless mesh network determines the LTLQ parameter associated with its links to surrounding nodes.

12. The method of claim 11 , wherein each nodes propagates to a network manager the LTLQ parameter associated with its links to surrounding nodes.

13. The method of claim 1 , wherein the step of routing comprises using the said link quality parameter to route via any one of multiple available radio frequencies per link.

14. The method of claim 13 , wherein an Ad-hoc On-demand Distance Vector (AODV) Multiple-Radio (AODV-MR) routing protocol is used to route data.

15. The method of claim 1 , wherein link metrics for a path are captured during a route discovery process in which:

each node propagates toward a destination node a route request (RREQ) message having appended thereto a corresponding channel identifier and link metric; and

each node propagates a route reply (RREP) message toward a source node having appended thereto a corresponding channel identifier and link metric.

16. The method of claim 15 , wherein link metrics within at least one of the RREQ and RREP messages are used to improve packet routing within a routing protocol.

17. The method of claim 16 , wherein:

each node propagates a route error (RERR) message toward a source node upon detecting a break in an active link.

18. The method of claim 16 , wherein:

each node performs a local repair of a broken active link.

19. A system, comprising:

an input/output circuit adapted to receive data streams;

a memory, for storing computer instructions for a method of processing the received data stream; and

a processor, for executing the computer instructions;

wherein while executing the computer instructions the processor operates to perform a method comprising:

determining, for each of a plurality of links supporting any of a plurality of data transmission paths, a long term link quality (LTLQ) parameter;

determining, for each of said plurality of links, an interference aware routing metric (iAWARE) parameter associated with any respective proximate links;

adapting the LTLQ parameter of each of said plurality of links according to the respective iAWARE parameter to determine thereby a link quality parameter; and

routing data according to said link quality parameter.

20. A computer program product stored on non-transitory readable medium wherein computer instructions, when processed by a computer, adapt the operation of the computer to perform a method of routing data in a wireless mesh network, the method comprising:

determining, for each of a plurality of links supporting any of a plurality of data transmission paths, a long term link quality (LTLQ) parameter;

determining, for each of said plurality of links, an interference aware routing metric (iAWARE) parameter associated with any respective proximate links;

adapting the LTLQ parameter of each of said plurality of links according to the respective iAWARE parameter to determine thereby a link quality parameter; and

routing data according to said link quality parameter.

21. Apparatus for routing data in a wireless mesh network, comprising:

means for determining, for each of a plurality of links supporting any of a plurality of data transmission paths, a long term link quality (LTLQ) parameter;

means for determining, for each of said plurality of links, an interference aware routing metric (iAWARE) parameter associated with any respective proximate links;

means for adapting the LTLQ parameter of each of said plurality of links according to the respective iAWARE parameter to determine thereby a link quality parameter; and

means for routing data according to said link quality parameter.

Assignments (12)