Channel assignments within a mesh network

• US 7,489,932 B2
• Filed: 06/03/2004
• Issued: 02/10/2009
• Est. Priority Date: 06/03/2004
• Status: Active Grant

• Current Assignee: Hitachi Energy Limited
• Original Assignee: Tropos Networks Incorporated (ABB Limited)
• Inventors: Chari, Amalavoyal, Behroozi, Cyrus, Srikrishna, Devabhaktuni
• Primary Examiner(s): Nguyen; Tu X
• Application Number:
  US10/861,767
• Publication Number:
  US 20050271006A1
• Time in Patent Office: 1,713 Days
• Field of Search: 455/7, 455/11.1, 455/13.1, 455/16, 455/447, 455/450, 455/451, 455/443, 370/329, 370/341, 375/132
• US Class Current: 455/447
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/044 based on the type of the allocated resource

Abstract

Embodiments of methods of assigning a channel to a link of an access node within a wireless mesh network, is disclosed. The method includes the access node receiving beacons over multiple channels, from at least one upstream device, and the access node selecting an uplink channel based upon the received beacons. Additional methods include the access node selecting a downlink channel so that different channels are assigned to consecutive links within a data path between a gateway and a down stream device. The different channels can include non-overlapping channels, or a combination of non-overlapping and at least partially overlapping channels. The method can further include selecting a downstream link channel based upon predetermined sequences of channel selections, and a hop count of the access node.

Claims

1. A method of assigning a channel to a link of an access node within a wireless mesh network, comprising:

the access node receiving beacons over multiple channels, from at least one upstream device;

the access node selecting an uplink channel based upon the received beacons;

the access node selecting a downlink channel so that different channels are assigned to consecutive links within a data path between a gateway and a down stream device, and based upon predetermined sequences of channel selections and a hop count of the access node, wherein the data path includes all links between the downstream device and the gateway.

2. The method of assigning channels of claim 1, wherein the access node simultaneously receives the beacons over multiple channels.

3. The method of assigning channels of claim 1, further comprising the access node receiving reverse beacons from the downstream device, and data path channel sequence selection is based upon channel preference information within the reverse beacons.

4. The method of assigning channels of claim 1, wherein the different channels comprise non-overlapping channels.

5. The method of assigning channels of claim 1, wherein at least some of the different channels comprise at least partially overlapping channels.

6. The method of assigning channels of claim 1, wherein a gateway originates the beacons, and the access node routes data traffic.

7. The method of assigning channels of claim 1, wherein the access node selecting an uplink channel base upon the received beacons comprises determining a path quality of the uplink channel based on a persistence of received beacons, and wherein if a beacon is not received during a routing cycle, the path quality is decreased, and further comprising the access node re-transmitting the beacon over the selected downlink channel if the path quality is sufficiently high.

8. The method of assigning channels of claim 7, wherein the channels are frequency channels, and non-overlapping channels occur first in the predetermined sequence, and overlapping channels, occur at an end of the predetermined sequence.

9. The method of assigning channels of claim 8, wherein the predetermined sequence is at least one of 1-6-11-3-8, 11-6-1-8-3, 1-7-13-4-10, 13-7-1-10-4, 1-8-14-4-11, 14-8-1-11-4, 1-7-14-4-10 and 14-7-1-10-4 channels of an 802.11(b) protocol.

10. The method of assigning channels of claim 8, wherein the predetermined sequence repeats if the number of links within the data path is greater than a number of channels within the predetermined sequence.

11. The method of assigning channels of claim 7, further comprising the access node receiving reverse beacons from the downstream device, and predetermined sequence selection is based upon channel preference information within the reverse beacons.

12. The method of assigning channels of claim 1, wherein channels include at least one of frequency channels, different spreading codes in a spread-spectrum CDMA system, different polarizations of the transmitted waveform, different spatial signatures as determined by a smart antenna or adaptive antenna array at the receiver.

13. The method of assigning channels of claim 1, wherein channels are frequency channels that include frequency bands as specified by an 802.11 protocol.

14. The method of assigning channels of claim 1, wherein the channels are frequency channels, and a first hop of the data path is at an opposite end of a frequency spectrum of the frequency channels as a second hop of the data path.

15. The method of assigning channels of claim 1, wherein the data path begins at a gateway that originates beacons.

16. The method of assigning channels of claim 15, wherein the beacons are retransmitted at each receiving access node, and include channel selection information of an upstream data path.

17. The method of assigning channels of claim 1, wherein the gateway is wirelessly connected to a network.

18. The method of assigning channels comprising:

the access node receiving beacons over multiple channels, from at least one upstream device;

the access node selecting an uplink channel based upon the received beacons;

receiving channel assignment information of which of available channels have been selected in an upstream data path of the access node

the access node selecting a downstream link channel based upon predetermined sequences of channel selections, and the channel assignment information, wherein the data path includes all links between the downstream device and the gateway.

19. A method of assigning channels to links of data paths within a wireless mesh network, comprising:

an access node receiving beacons over multiple channels, from at least one upstream device;

the access node selecting an uplink channel based upon the received beacons; and

assigning different channels to consecutive links within each of the data paths of the wireless mesh network and based upon predetermined sequences of channel selections and a hop count of the access node.

20. The method of assigning channels of claim 19, further comprising:

each access node within the mesh network selecting a downstream link channel based upon the predetermined sequences of channel selections, and the hop count of the access node.

21. The method of assigning channels of claim 19, wherein the access node simultaneously receives the beacons over multiple channels.

22. The method of assigning channels of claim 20, further comprising the access node receiving reverse beacons from the downstream device, and predetermined sequence selection is based upon channel preference information within the reverse beacons.

23. The method of assigning channels of claim 19, wherein a gateway originates the beacons, and the access node routes data traffic.

24. The method of assigning channels of claim 20, further comprising:

each access node within the mesh network receiving channel assignment information of which of available channels have been selected in an upstream data path of the access node,

each access node selecting a downstream link channel based upon predetermined sequences of channel selections, and the corresponding channel assignment information.

25. The method of assigning channels of claim 19, wherein channels are frequency channels that include frequency bands as specified by the 802.11 protocol.

26. The method of assigning channels of claim 19, wherein the channels are frequency channels, and a first hop of each data path is at an opposite end of a frequency spectrum of the frequency channels as a second hop of the data path.

27. The method of assigning channels of claim 19, wherein the channels are frequency channels, and non-overlapping channels occur first in the predetermined sequence, and overlapping channels occur at an end of the predetermined sequence.

28. The method of assigning channels of claim 24, wherein the predetermined sequence repeats if the number of links within the data path is greater than a number of channels within the predetermined sequence.

29. The method of assigning channels of claim 19, wherein the beacons are retransmitted at each receiving access node, and include channel selection information of an upstream data path.

30. The method of assigning channels of claim 23, wherein the gateway is wirelessly connected to a network.