Method of managing a distributed communications system

• US 20040125786A1
• Filed: 02/13/2003
• Published: 07/01/2004
• Est. Priority Date: 08/25/2000
• Status: Abandoned Application

• Current Assignee: Rafael - Armament Development Authority Ltd.
• Original Assignee: Rafael - Armament Development Authority Ltd.
• Inventors: Fuchs, Itzhak
• Application Number:
  US10/344,640
• Publication Number:
  US 20040125786A1
• Time in Patent Office: Days
• US Class Current: 370/350
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

A method of coordinating communication among three stations (A, B, C) on networks includes: (a) selecting one membership network for each station; (b) synchronizing the stations to a superframe (20) including a transmission slot (22), and a relay slot (26); (c) determining, for each station, which other station is a near neighbor and which other station is a far neighbor; and (d) broadcasting a message for the stations having a far neighbor sharing one of the membership networks by: (i) designating a near neighbor sharing the network with each broadcasting station and the far neighbor, as a relay station, (ii) transmitting the message on the shared network during each transmission slot, by the broadcasting station, (iii) receiving the message during one of the transmission slots, by the relay station, and (iv) transmitting the message on the shared network during each relay slot, by the relay station.

Claims

1. A method of coordinating communication among at least three stations on a plurality of networks, each station having an identifier, comprising the steps of:

(a) selecting, for each station, from among the networks, at least one membership network;

(b) synchronizing the stations to at least one superframe that includes;

(i) at least one transmission slot, and

(ii) at least one relay slot,

all of said at least one relay slot being subsequent to all of said at least one transmission slot;

(c) determining, for each station, which at least one other station is a near neighbor thereof and which at least one other station is a far neighbor thereof; and

(d) for each of at least one of said stations that has a far neighbor that shares therewith one of said at least one membership networks, broadcasting a message by steps including;

(i) designating a near neighbor, of said each broadcasting station, that shares said shared network with said each broadcasting station and said far neighbor thereof, as a relay station,

(ii) transmitting said message on said shared network during each said at least one transmission slot, by said each broadcasting station,

(iii) receiving said message during one of said at least one transmission slot, by said relay station, and

(iv) transmitting said message on said shared network during each said at least one relay slot, by said relay station.

2. The method of claim 1, wherein said designating is effected by steps including:

(A) each said broadcasting station including the identifier of said relay station in said message.

3. The method of claim 2, wherein a like number of said at least one membership network is selected for each station, and wherein said at least one transmission slot is equal in number to said at least one membership network of each station, the method further comprising the step of:

(e) for each station other than said at least one broadcasting station, listening to each said at least one membership network during a corresponding said transmission slot

4. The method of claim 3, wherein said designating is effected by steps further including:

(B) for each station other than said at least one broadcasting station that receives one of said messages during one of said at least one transmission slot, recognizing the identifier thereof in said received message.

5. The method of claim 1, further comprising the step of:

(e) for each station other than said at least one relay station, listening to at least one of said at least one membership network thereof during a corresponding said at least one relay slot.

6. The method of claim 5, wherein at least two said membership networks are selected for each said station, and wherein said at least one membership network listened to by each said at least one broadcasting station is different from said shared membership network of said each at least one broadcasting station.

7. The method of claim 1, wherein said stations are synchronized to a plurality of successive said superframes, all said superframes having a like number of said at least one transmission slot and a like number of said at least one relay slot

8. The method of claim 7, wherein at least one said superframe includes a plurality of control slots, the method further comprising the step of:

(e) providing a control channel that is common to all the stations; and

wherein said determining is effected by steps including;

(i) each station broadcasting a respective control packet on said control channel during a respective one of said control slots of said at least one superframe.

9. The method of claim 8, wherein said determining further includes the steps of.

(ii) for each station, and for each said neighbor thereof, said each station receiving said respective control packet of said each neighbor thereof during one of said control slots;

and

(iii) each station maintaining, for each at least one membership network thereof, a list of the identifiers of said neighbors, wherefrom said each station has received said respective control packets.

10. The method of claim 9, wherein said determining further includes the steps of:

(iv) each station including said at least one neighbor identifier list in said respective control packet thereof; and

(v) for each station, for each at least one network thereof, and for each far neighbor thereof, said each station identifying said each far neighbor thereof from said neighbor identifier list received by said each station that includes the identifier of said each far neighbor of said each station.

11. The method of claim 9, wherein said broadcasting of said control packet is effected by each station a plurality of times, and wherein said determining further includes the step of:

(iv) for each station, if a time since a last receipt of said respective control packet of a neighbor thereof exceeds a threshold, deleting said neighbor from each said list wherein the identifier of said neighbor appears.

12. The method of claim 7, wherein a like number of at least two of said membership networks are selected for each said station, wherein said at least one relay slot of each said superframe is less in number than said at least two membership networks of each station, the method further comprising the step of:

(e) for each station other than said at least one relay station;

listening to each said membership network thereof during a corresponding said relay slot, during successive said superframes.

13. The method of claim 12, wherein all said transmission slots are of equal duration, and wherein, if said message has a duration greater than said transmission slot duration, said transmitting of said message is effected by transmitting a plurality of submessages of said message, each said submessage having a duration at most equal to said transmission slot duration, successive said submessages being transmitted during successive said superframes, with each said successive submessage being transmitted in each said transmission slot of a corresponding said successive superframe.

14. The method of claim 13, further comprising the step of:

(f) for each station other than said at least one relay station;

if one of said submessages is received on one of said membership networks during one of said relay slots, listening to said one membership network during a corresponding said relay slot of a succeeding said superframe.

15. A method of communicating among a plurality of stations on a plurality of networks, each station having an identifier, comprising the steps of:

(a) selecting, for each station, from among the networks, at least one membership network;

(b) synchronizing the stations to at least one superframe that includes a plurality of transmission slots;

(c) determining, for each station, which at least one other station is a near neighbor thereof; and

(d) for each of at least one of said stations that has at least one near neighbor, broadcasting a message during each said transmission slot on one of said at least one membership network that is shared by said each station and by said at least one neighbor thereof.

16. The method of claim 15, wherein a like number of said at least one membership network is selected for each station, and wherein said at least one transmission slot is equal in number to said at least one membership network of each station, the method further comprising the step of:

(e) for each station other than said at least one broadcasting station, listening to each said at least one membership network during a corresponding said transmission slot.

17. The method of claim 15, wherein said stations are synchronized to a plurality of successive said superframes, all said superframes having a like number of said at least one transmission slot.

18. The method of claim 17, wherein at least one said superframe includes a plurality of control slots, the method further comprising the step of:

(e) providing a control channel that is common to all the stations; and

wherein said determining is effected by steps including;

(i) each station broadcasting a respective control packet on said control channel during a respective one of said control slots of said at least one superframe.

19. The method of claim 18, wherein said determining further includes the steps of:

(ii) for each station, and for each neighbor thereof, each station receiving said respective control packet of said each neighbor during one of said control slots; and

(iii) each station maintaining, for each at least one membership network thereof, a list of the identifiers of said neighbors, wherefrom said each station has received said respective control packets.

20. The method of claim 18, wherein said broadcasting of said control packet is effected by each station a plurality of times, and wherein said determining further includes the step of:

(iv) for each station, if a time since a last receipt of said respective control packet of a neighbor thereof exceeds a threshold, deleting said neighbor from each said list wherein the identifier of said neighbor appears.