Communication protocol for a wireless mesh architecture

• US 7,336,642 B2
• Filed: 08/07/2003
• Issued: 02/26/2008
• Est. Priority Date: 08/07/2003
• Status: Active Grant

• Current Assignee: Trilliant Networks Incorporated
• Original Assignee: SkyPilot Networks Incorporated (Trilliant Networks Incorporated)
• Inventors: Gordon, Paul, Rich, Mark J., Frei, Randy
• Primary Examiner(s): Nguyen; Chau
• Assistant Examiner(s): Hartmann; Kenneth R
• Application Number:
  US10/636,382
• Publication Number:
  US 20050030968A1
• Time in Patent Office: 1,664 Days
• Field of Search: 370/348, 370/442, 370/443, 370/444, 370/449
• US Class Current: 370/348
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 74/06 using polling
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A wireless mesh communication protocol that dynamically assigns communication time-slots and frequencies to mesh nodes. A first node is established as a PC that sequentially polls other nodes. A second node responds at a predetermined time with information that includes database records, and then a third node responds similarly. The second node is then established as the PC and the first node is polled during dynamically allocated time-slots and on a frequency that depend on the second node'"'"'s database records. The third node is then established as a PC and acts similarly. In both cases the first node responds by sending information and data records. The first node is then re-established as the PC. The first node then polls the second and third nodes at times and frequencies that depend on the first node'"'"'s database records.

Claims

1. A mesh network that uses a distributed polling coordination function comprising:

a source acting as a polling coordinator (PC) by producing first polling information and second polling information at predetermined first and second time-slots;

a first node that receives said first polling information during said first time-slot and that sends first responsive information to said source; and

a second node that receives said second polling information during said second time-slot and that sends second responsive information to said source;

wherein said first and second time-slots occur relative to a common time frame;

wherein said first responsive information assigns a time and a frequency for future polling of said first node by said source, and a time for said first node to act as a PC; and

wherein said second responsive information assigns a time and a frequency for future polling of said second node by said source, and a time for said second node to act as a PC; and

wherein said second responsive information depends on said first responsive information.

2. A mesh network according to claim 1 wherein the source is a Mesh Gateway.

3. A mesh network according to claim 1 wherein said first node polls said source at said time for said first node to act as a PC.

4. A mesh network according to claim 1, wherein said first node compares said first polling information against database information to detect scheduling conflicts.

5. A mesh network according to claim 4, wherein said first responsive information depends on whether a scheduling conflict is detected.

6. A mesh network according to claim 5, wherein said first responsive information informs said source that a scheduling conflict is detected.

7. A mesh network according to claim 1 wherein said source is a CPE device.

8. A method of communicating within a wireless mesh network having nodes comprising:

establishing a plurality of time-slots in each time frame of a sequence of time frames;

having a first node act as a polling coordinator (PC) by sending first polling information to a second node during a first time-slot in a first time frame;

having said second node receive said first polling information in said first time-slot, wherein said second node compares said first polling information with second node database information to determine if a scheduling conflict exists;

having said second node respond to said first node by sending first responsive information, wherein said first responsive information depends on whether a scheduling conflict exits;

having said first node act as a PC by sending second polling information during a second time-slot in said first time frame to a third node, wherein said second time-slot overlaps with said first time-slot, and wherein said second polling information depends on said first responsive information;

having said second node act as a PC by sending first polling information to said first node during a first time-slot in a second time frame, wherein said first time-slot in said second time frame depends on said first responsive information; and

having said third node act as a PC by sending first polling information to said first node during a first time-slot in a third time frame.

9. A method of communicating according to claim 8, wherein said first time-slot in said third time frame depends on said first responsive information.

10. A method of communicating according to claim 8 wherein said first responsive information includes information from said second node database information.

11. A method of communicating according to claim 10 wherein said second node database information includes information regarding the location of said second node.

12. A method of communicating according to claim 11 wherein said second node database information includes information regarding the frequency at which said second node will communicate with said first node in said first time-slot in said second time frame.

13. A method of communicating according to claim 12 wherein said second node database information includes information regarding the interference area of said second node.

14. A method of communicating according to claim 13 wherein said interference area depends on the frequency, the transmit power, and the terrain adjacent said second node.

15. A method of communicating according to claim 8 wherein said first, second, and third nodes operate in a time division duplex fashion.

16. A method of communicating according to claim B wherein each time frame is synchronized to a clock.

17. A method of communicating according to claim 16 wherein each time frame Is identified by a special purpose time-slot.

18. A method of communicating within a wireless mesh network having nodes comprising:

establishing a plurality of time-slots in a plurality of subframes in a sequence of time frames;

establishing a first node as a polling coordinator (PC);

having said first node poll a second node for information at a predetermined first time within a first subframe;

having said second node send said first node information during a first set of time-slots in said first subframe;

having said first node poll a third node for information at a predetermined second time within said first subframe;

establishing said second node as a PC during a second subframe;

having said second node poll said first node for information at a predetermined first time within said second subframe;

having said first node send said second node information during a first set of time-slots in said second subframe; and

having said second node poll said third node for information at a predetermined second time within said second subframe;

wherein polling said second node includes sending database information that determines a number of time-slots in said first set of time-slots in said second subframe.

19. A method according to claim 18 wherein said predetermined first time within said second subframe is determined by polling during said first time within said first subframe.

20. A method according to claim 19 further including establishing said third node as a PC during a third subframe.

21. A method according to claim 20 wherein the number of time-slots depends on an amount of information to be sent during said second subframe.

22. A method of communicating within a wireless mesh network having a plurality of nodes comprising:

establishing a plurality of time-slots;

establishing a polling coordinator (PC);

determining the neighboring nodes of said PC;

scheduling a first polling signal for a first neighboring node at a predetermined first time within a first time frame;

scheduling a second polling signal for a second neighboring node at a predetermined second time within said first time frame

having said first neighboring node look for a start of said scheduled first polling signal at said predetermined first time;

having said first neighboring node send a first information to said PC if said start of said scheduled first polling signal is found, said first information assigning a time and a frequency for future polling of said first neighboring node by said PC;

having said second neighboring node look for a start of said scheduled second polling signal at said predetermined second time;

having said second neighboring node send a second information to said PC if said start of said scheduled second polling signal is found, said second information assigning a time and a frequency for future polling of said second neighboring node by said PC.