Unifying slot assignment protocol multiple access system

• US 6,331,973 B1
• Filed: 04/30/1999
• Issued: 12/18/2001
• Est. Priority Date: 04/30/1999
• Status: Expired due to Term

• Current Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Becker, Michael S., Harwell, Henry O., Stevens, James A., Young, C. David, Krueger, Roy W.
• Primary Examiner(s): Olms, Douglas
• Assistant Examiner(s): Pizarro, Ricardo M.
• Application Number:
  US09/303,528
• Time in Patent Office: 963 Days
• Field of Search: 370/321, 370/310, 370/338, 370/336, 370/329, 370/335, 370/330, 370/228, 370/227, 370/337, 370/347, 370/343, 370/441, 370/280, 370/468, 370/277, 370/342
• US Class Current: 370/337
• CPC Class Codes: H04B 7/2656 for structure of frame, burst
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/535 based on resource usage policies
• CPC Class Codes: H04W 74/04 Scheduled access hybrid access H04W74/02
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A method and system for managing communication resources between nodes in a network, and more particularly to a dynamic distributed multi-channel time division multiple access (TDMA) slot assignment method is presented. The method and apparatus include a set of higher level heuristics that enable the wireless channel access scheme to address predetermined characteristics of the wireless channel access system. These predetermined heuristics include using bootstrap slots, adaptive broadcast cycles, channelized neighborhoods, standby slots, speculation slots, neighbor segregation, hard circuits, and soft circuits.

Claims

1. A method for automatically managing communication channel resources between nodes having neighboring nodes in a network of transceiver nodes, wherein each node communicates during specific time slots and uses multiple frequencies using a time division multiple access structure, the method comprising:

storing possible communications time slots and frequencies between nodes in the network at each node;

announcing and transmitting from a first node during a specific time slot, a specific transmit slot and frequency and the identification of a second node to all neighboring nodes of the first node comprising a first set of neighboring nodes;

transmitting from the first node in a bootstrap slot a control packet containing;

a set of slot and frequency pairs on which the first node is transmitting;

a set of slot and frequency pairs on which the first node is receiving; and

a set of slot and frequency pairs on which the first set of neighboring nodes are transmitting on;

identifying in each of the nodes of the first set of neighboring nodes the announced selected transmit slot and frequency used to establish substantially contention free communication on the selected transmit slot and frequency between the first and second nodes; and

assigning slot and frequency pairs from the communications channel resources by utilizing a heuristics.

2. The method of claim 1 further comprising:

transmitting from the first set of neighboring nodes to all neighboring nodes of each node in the first set of neighboring nodes comprising a second set of neighboring nodes, the announced transmit slot and frequency used to establish contention free communication between the first and second nodes, and identifying in tables of each of the second set of neighboring nodes the announced transmit slot and frequency.

3. The method of claim 2 further comprising:

the first set of neighboring nodes each receiving confirmation from a second set of neighboring nodes that the announced slot and frequency have been identified in the tables of the second set of neighboring nodes; and

the first node receiving confirmation from the first set of neighboring nodes that the announced transmit slot and frequency have been identified in the second set of neighboring nodes.

4. The method of claim 3 further comprising:

transmitting a confirmed message from the second node to the first node thereby establishing communication using the selected transmit slot and frequency.

5. The method of claim 2 further comprising:

identifying, to the first set of neighboring nodes, slot and frequencies not being used by the first node to thereby make available unused slots and frequencies to the first and second sets of neighboring nodes.

6. The method of claim 1 further comprising:

resolving conflicts between nodes which have announced a desire to transmit on a same slot and frequency.

7. The method of claim 1 wherein storing possible communications slots and frequencies further comprises assigning a set of bootstrap slots for all nodes to transmit the control packets.

8. The method of claim 7 wherein assigning slot and frequency pairs further includes dynamically assigning the set of bootstrap slots based on the density of neighboring nodes with a bootstrap slot heuristic.

9. The method of claim 1 wherein storing possible communication time slots and frequencies includes assigning a plurality of broadcast slots to nodes to transmit to all neighboring nodes and assigning a plurality of reservation slots to nodes to communicate between two nodes.

10. The method of claim 9 wherein assigning the plurality of reservation slots further includes assigning the reservation slots as standby broadcast slots for use by a same node as the reservation slot assignment by using a standby slot heuristic.

11. The method of claim 10 further comprising adaptively assigning the standby broadcast slots according to network density using an adaptive broadcast cycle heuristic.

12. The method of claim 11 further comprising reassigning standby broadcast slots with the adaptive broadcast cycle heuristic by using slot poaching.

13. The method of claim 9 further comprising establishing channelized neighborhoods with a channelized neighborhood heuristic that allows standby broadcast slots to be assigned on different frequencies.

14. The method of claim 10 further comprising selectively permitting contention access with a speculation slot heuristic that allows a node to transmit in an idle standby broadcast slot not assigned to the node.

15. The method of claim 11 further comprising selectively permitting contention access with a speculation slot heuristic that allows a node to transmit in an idle standby broadcast slot not assigned to the node.

16. The method of claim 1 wherein assigning slot and frequency pairs further includes segregating neighbors based upon transmission rate between a node and it neighbors with a neighbor segregation heuristic.

17. The method of claim 9 further comprising segregating neighbors based upon transmission rate between a node and it neighbors with a neighbor segregation heuristic.

18. The method of claim 1 wherein assigning slot and frequency pairs further includes dynamically assigning enough slots between nodes to satisfying traffic requirements by establishing soft circuits with a soft circuit heuristic.

19. The method of claim 1 wherein assigning slot and frequency pairs further includes reserving all slots along a path from source to destination before transmitting traffic by establishing hard circuits with a hard circuit heuristic.

20. A communication network comprising:

a network of transceiver nodes each node having neighbors;

a time division multiple access structure having broadcast slots and reservation slots and the time division multiple access structure including;

a slot assignment protocol that allows nodes to choose available transmit slots based on slot usage by neighboring nodes and coordinates the activation of the slots for the nodes;

a plurality of bootstrap slots for each node to transmit slot assignment information from the slot assignment protocol; and

at least one slot handling heuristic that adaptively and dynamically controls the assignment of slots.

21. The communications network of claim 20 wherein the plurality of bootstraps slots are fixed bootstrap slots assigned with one bootstrap slot for each transceiver node.

22. The communications network of claim 20 wherein the time division multiple access structure reservation slots are also assigned as standby broadcast slots for use by a same node as the reservation slots by using a standby slot heuristic as the slot handling heuristic.

23. The communications network of claim 20 wherein the at least one slot handling heuristic includes a bootstrap slot heuristic for dynamically assigning the bootstrap slots to the transceiver nodes.

24. The communication network of claim 21 wherein the bootstrap slot protocol is a fixed bootstrap slot protocol.

25. The communications network of claim 22 wherein the at least one slot handling heuristic includes an adaptive broadcast cycle for adaptively assigning the standby broadcast slots according to network density.

26. The communications network of claim 22 wherein the at least one slot handling heuristic includes a channelized neighborhood heuristic that allows standby broadcast slots to be assigned on different frequencies when the number of neighboring nodes increases.

27. The communication network of claim 22 wherein the at least one adaptive slot handling heuristic includes a soft circuit heuristic for allocating time slots in response to traffic demands during transmission of information.

28. The communication network of claim 22 wherein the at least one adaptive slot handling heuristic includes a hard circuit heuristic for allocating time slots prior to transmitting information.

29. The communications network of claim 22 wherein the at least one slot handling heuristic includes a speculation slot heuristic that allows other nodes to use standby broadcast slots that are unused by the node assigned to the standby broadcast slot.

30. The communication network of claim 20 wherein the at least one adaptive slot handling heuristic includes a neighbor segregation heuristic that divides the neighbors of a node into at least two groups and adjusts transmission parameters separately for each group.

31. A method for automatically managing communication channel resources between nodes having neighboring nodes in a network of transceiver nodes, wherein each node communicates during specific time slots and uses multiple frequencies using a time division multiple access structure, the method comprising:

assigning broadcast and reservation slots and frequencies to the nodes with a slot assignment protocol;

assigning bootstrap slots to the nodes;

sharing the broadcast and reservation slot and frequency assignments between nodes using the bootstrap slots; and

dynamically adapting the slot and frequency assignments by utilizing a family of heuristics.

32. The method of claim 31 further comprising

dynamically assigning the bootstrap slots to nodes of the network using a bootstrap heuristic in the family of heuristics.

33. The method of claim 31 further comprising

assigning the reservation slots as standby broadcast slots for use by a same node as the reservation slot assignment using a standby slot heuristic in the family of heuristics.

34. The method of claim 33 further comprising adaptively assigning the broadcast slots and the standby broadcast slots in a broadcast cycle according to network density using an adaptive broadcast cycle heuristic in the family of heuristics.

35. The method of claim 34 further comprising assigning standby broadcast slots on different frequencies when the network density exceeds the capacity of the broadcast cycle using a channelized neighborhood heuristic in the family of heuristics.

36. The method of claim 33 further comprising

allowing neighboring nodes to transmit information in idle standby broadcast slots assigned to a first node using a speculation slot heuristic in the family of heuristics.

37. The method of claim 31 further comprising

segregating neighbors into at least two groups based on the transmission quality of each neighbor using a neighbor segregation heuristic in the family of heuristics.

38. The method of claim 31 further comprising

establishing hard circuits by reserving all slots alone a path from a source node to a destination node before transmitting by using a hard circuit heuristic in the family of heuristics.

39. The method of claim 31 further comprising

establishing soft circuits by assigning enough slots between nodes to satisfying traffic requirements by using a soft circuit heuristic in the family of heuristics.