Assignment of channels to links of nodes within a mesh network

• US 20050163144A1
• Filed: 03/07/2005
• Published: 07/28/2005
• Est. Priority Date: 03/26/2001
• Status: Active Grant

• Current Assignee: Hitachi Energy Switzerland AG (Hitachi, Ltd.)
• Original Assignee: Tropos Networks Incorporated (ABB Limited)
• Inventors: Behroozi, Cyrus, Srikrishna, Devabhaktuni, Chari, Amalavoyal
• Granted Patent: US 7,564,862 B2
• Time in Patent Office: Days
• US Class Current: 370/431
• CPC Class Codes: H04K 2203/18 for wireless local area networks or WLAN
• CPC Class Codes: H04K 3/226 Selection of non-jammed channel for communication spectrum sharing arrangements H04W16/14; selection of wireless resources by user or terminal H04W72/02
• CPC Class Codes: H04L 1/16 in which the return channel carries supervisory signals, e.g. repetition request signals
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/04 Wireless resource allocation
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

It is the object of this invention to provide a method of increasing the data throughput of a multi-hop wireless link. A method is provided which mitigates self-interference, without precluding the use of omni-directional transceivers. Distributed protocols for channel allocations in a multi-hop wireless communication system are described. These protocols result in channel allocations that increase the capacity utilization of the network and render the system robust to localized interferers and jammers.

Claims

1-18. -18. (canceled)

19. A method of assigning channels to links of a node of a mesh network, the mesh network including the node and an upstream node, the method comprising:

assigning a first channel to an uplink of the node;

assigning a second channel to a downlink of the node;

maintaining the first channel and the second channel distinct from an uplink channel of the upstream node.

27. The method of claim 38 wherein the routing information is propagated in the network on a dedicated channel.

29. The method of claim 39, wherein assigning the downlink channel for a node comprises:

determining a plurality of potential channels for communication;

sending a reservation packet to trigger testing of each of the plurality of potential channels; and

determining a best channel based on responses to the reservation packet.

30. The method of claim 41 wherein testing comprises:

each downstream node sending a plurality of packets to the node; and

evaluating a channel with the best link quality.

31. The method of claim 42 wherein link quality is estimated by at least one of throughput on the link, packet error rate on the link, signal-to-noise ratio observed on the link, latency observed on the link.

20. The method of claim 31, wherein the uplink of the node provides communication between the node and the upstream node.

21. The method of claim 31, wherein the downlink of the node provides communication between the node and a downstream node.

22. The method of claim 31, wherein the uplink and downlink of the node comprise directional antennas.

23. The method of claim 31, wherein the uplink and downlink of the node comprise omni-directional antennas.

24. The method of claim 31, further comprising:

assigning of the second channel and the third channel for the node based on a number of hops from the node to a distinguished node.

28. The method of claim 31 wherein the uplink channel of the node is assigned by the default gateway of the node.

32. A mesh network system that includes assigning channels to links of a node of a mesh network, the mesh network including the node and an upstream node, the method comprising:

means for assigning a first channel to an uplink of the node;

means for assigning a second channel to a downlink of the node;

means for maintaining the first channel and the second channel distinct from an uplink of the upstream node.

33. The system of claim 44, further comprising:

means for assigning of the second channel and the third channel for the node based on a number of hops from the node to a distinguished node.

34. The system of claim 45, wherein the number of hops is determined from information carried in routing packets.

35. A mesh network comprising:

a plurality of access nodes including at least one distinguished node;

a plurality of links between the access nodes;

wherein

any three consecutive links within a multi-hop chain from any node to the distinguished node operate on different channels.

36. The network of claim 47, further comprising:

means for assigning channels to links based on a number of hops to the distinguished node.

25. The method of claim 36 wherein the number of hops is determined from information carried in routing packets.

26. The method of claim 37 wherein the routing information is propagated in the network on some or all of the channels available in the system.

37. The access node of claim 36 wherein the number of hops is determined from information carried in routing packets.