MESSAGE ROUTING IN WIRELESS MESH NETWORKS

• US 20110110345A1
• Filed: 11/03/2010
• Published: 05/12/2011
• Est. Priority Date: 11/06/2009
• Status: Active Grant

• Current Assignee: Maxlinear Incorporated
• Original Assignee: Quantenna Communications, Inc. (ON Semiconductor Corporation)
• Inventors: Schelstraete, Sigurd, Heidari, Sam, Narasimhan, Ravi, Goldsmith, Andrea
• Granted Patent: US 8,634,434 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 40/06 based on characteristics of available antennas

Abstract

Disclosed are methods and apparatuses related to the routing of communications in a wireless mesh network so as to provide improved range, reliability and/or throughput. At least some aspects of the techniques and apparatuses can be implemented in an intermediary node (relay node) on a wireless mesh network. The relay node and other devices on the wireless network may implement a form of multiple-input multiple-output (MIMO) communication, such as multi-user MIMO (MU-MIMO). The devices on the network can communicate in accordance with IEEE standard 802.11.

Claims

1. A method comprising:

receiving, at an intermediary node on a wireless mesh network, a first transmission of information at a first frequency over the mesh network during a first timeslot of a time interval; and

forwarding the received information to another node on the wireless mesh network, by sending from the intermediary node a second transmission of the information at a second frequency during a second timeslot of the time interval.

2. A method as recited in claim 1, wherein the intermediary node is operable for multiple-input multiple-output (MIMO) communication on the wireless mesh network.

3. A method as recited in claim 1, wherein the first transmission and the second transmission comply with IEEE standard 802.11.

4. A method as recited in claim 1, further comprising:

prior to the second transmission, dynamically selecting the second frequency to use for the second transmission, based on a real-time measurement of a parameter on the wireless mesh network.

5. A wireless mesh node comprising:

a first communication unit which operates in a station mode to receive a wireless transmission of information from an access point on the mesh network; and

a second communication unit, coupled to the first communication unit, which operates in an access point mode to forward the received information, from the mesh node to a station on the mesh network other than the access point.

6. A wireless mesh node as recited in claim 5, wherein the mesh node is operable for multiple-input multiple-output (MIMO) communication.

7. A wireless mesh node as recited in claim 5, further comprising an interconnect coupling the second communication unit to the first communication unit.

8. A wireless mesh node as recited in claim 7, wherein the interconnect is an ethernet-based interconnect.

9. A wireless mesh node as recited in claim 5, wherein the first communication unit and the second communication unit are implemented in separate chipsets.

10. A wireless mesh node as recited in claim 5, wherein the first communication unit and the second communication unit operate in accordance with IEEE standard 802.11.

11. A wireless mesh node as recited in claim 5, wherein the first communication unit receives the transmission at a first frequency, and wherein the second communication unit generates a retransmission of the information at a second frequency.

12. A wireless mesh node as recited in claim 11, wherein the second frequency is selected dynamically based on a real-time measurement of a parameter on the wireless mesh network.

13. A wireless mesh node as recited in claim 5, wherein the mesh node is configured to use the first communication unit to receive the information from the access point during a first timeslot of a time interval and to use the second communication unit to forward the information to the station during a second timeslot of the time interval.

14. A wireless mesh node as recited in claim 5, wherein the first frequency in the second frequency or both within a single, specified frequency band.

15. A wireless mesh node comprising:

a first multiple-input multiple-output (MIMO) transceiver chipset including circuitry which operates in a station mode to receive a transmission of information at a first frequency from an access point on a wireless mesh network during a first timeslot; and

a second MIMO transceiver chipset including circuitry which operates in an access point mode to forward the received information, from the mesh node at a second frequency to a station on the wireless mesh network during a second timeslot; and

an interconnect coupling the first transceiver chipset to the second transceiver chipset.

16. A mesh node as recited in claim 15, wherein the first transceiver chipset and the second transceiver chipset operate in accordance with IEEE standard 802.11.

17. A mesh node as recited in claim 15, wherein the first frequency in the second frequency or both within a single, specified frequency band.

18. A mesh node as recited in claim 15, wherein the second frequency is selected dynamically based on a real-time measurement of a parameter on the wireless mesh network.

19. A method of operating an intermediary node on a wireless mesh network, the method comprising:

receiving at the intermediary node a first transmission, at a first frequency, from a source node on the wireless mesh network, while at least one node on the wireless mesh network other than the intermediary node is using a second frequency to communicate on the wireless mesh network;

measuring at the intermediary node a signal level of a signal detected at the second frequency; and

in response to a determination that the signal level of the signal detected at the second frequency is below a specified level, using the second frequency to send a second transmission from the intermediary node to a destination node on the wireless mesh network.

20. A method as recited in claim 19, wherein the first transmission and the second transmission are in accordance with IEEE standard 802.11.

21. A method as recited in claim 19, wherein the intermediary node is operable for multiple-input multiple-output (MIMO) communication on the wireless mesh network.

22. A method comprising:

receiving, at an intermediary node on a wireless mesh network, a first transmission containing a message intended for a destination node on the wireless mesh network, from a source node on the wireless mesh network; and

sending a second transmission containing the message from the intermediary node to a destination node on the wireless mesh network, including synchronizing the second transmission with a transmission from the source node.

23. A method as recited in claim 22, wherein the first transmission and the second transmission are at the same frequency.

24. A method as recited in claim 22, wherein the first transmission and the second transmission are at different frequencies.

25. A method as recited in claim 22, wherein synchronizing the second transmission with a transmission from the source node comprises synchronizing the second transmission with the first transmission.

26. A method as recited in claim 25, wherein the first transmission and the second transmission are at different frequencies.

27. A method as recited in claim 22, wherein synchronizing the second transmission with a transmission from the source node comprises synchronizing the second transmission with a third transmission, and wherein the third transmission is a retransmission of the message.

28. A method as recited in claim 27, wherein the second transmission and the retransmission of the message are synchronized to enable coherent combining of the second transmission and the retransmission at the destination node.

29. A method as recited in claim 27, wherein said synchronizing comprises initiating the second transmission a predetermined amount of time after a maximum time period for an acknowledgment of the first transmission has expired.

30. A method as recited in claim 27, wherein determining, in the intermediary node, whether the destination node successfully received the first transmission comprises:

listening for an acknowledgement of the first transmission, from the destination node; and

determining that the destination node did not successfully receive the first transmission if an acknowledgment from the destination node is not detected within a specified time interval.

31. A method as recited in claim 27, wherein the second transmission and the retransmission are at the same frequency.

32. A method as recited in claim 27, wherein the second transmission and the retransmission are at different frequencies.

33. A method as recited in claim 22, further comprising:

prior to the second transmission, dynamically selecting a frequency to use for the second transmission, based on a real-time measurement of a parameter on the wireless mesh network.

34. A method as recited in claim 22, wherein the first transmission and the second transmission are in accordance with IEEE standard 802.11.

35. A method as recited in claim 22, wherein the intermediary node is operable for multiple-input multiple-output (MIMO) communication on the wireless mesh network.

36. A method comprising:

receiving, at a destination node on a wireless mesh network, a first transmission from a source node on the wireless mesh network;

receiving, at the destination node, a second transmission from an intermediary node on the wireless mesh network, wherein the second transmission is synchronized with the first transmission;

coherently combining the first transmission and the second transmission in the destination node; and

extracting a message from a result of coherently combining the first transmission and the second transmission.

37. A method as recited in claim 36, wherein the first transmission is a retransmission of an earlier transmission from the source node that was not successfully received by the destination node.

38. A method as recited in claim 36, wherein the first transmission and the second transmission are at the same frequency.

39. A method as recited in claim 36, wherein the first transmission and the second transmission are at different frequencies.

40. A method as recited in claim 36, wherein the first transmission and the second transmission are in accordance with IEEE standard 802.11.

41. A method as recited in claim 36, wherein the intermediary node is operable for multiple-input multiple-output (MIMO) communication on the wireless mesh network.

42. A method as recited in claim 36, wherein said coherently combining comprises:

coherently combining the first transmission and the second transmission in the destination node prior to down-converting the first transmission and the second transmission to respective baseband signals.

43. A method as recited in claim 36, wherein said coherently combining comprises:

coherently combining the first transmission and the second transmission in the destination node after down-converting the first transmission and the second transmission to respective baseband signals.

44. A method as recited in claim 36, wherein said coherently combining comprises:

coherently combining the first transmission and the second transmission in the destination node after demodulating the first transmission and the second transmission.

45. A method comprising:

receiving a signal at an intermediary node in a wireless mesh network; and

using frequency division multiplexing (FDM) at the intermediary node in the wireless mesh network, to communicate with at least one other node in the wireless mesh network.

46. A method as recited in claim 45, wherein using FDM at the intermediary node comprises:

transmitting signals from the intermediate node to at least one other node concurrently at a plurality of different frequencies.

47. A method as recited in claim 45, wherein using FDM at the intermediary node comprises:

receiving, by the intermediate node, a plurality of signals concurrently from at least one other node, wherein each of the plurality of signals is at a different frequency.

48. A method as recited in claim 45, wherein using FDM at the intermediary node comprises:

receiving, by the intermediate node, a first signal at a first frequency from a first node on the wireless mesh network; and

sending a second signal from the intermediate nodes to a second node on the wireless mesh network, concurrently with said receiving the first signal at the intermediate node.

49. A method as recited in claim 45, further comprising:

using FDM in combination with time division multiplexing at the intermediary node.