Using direct cluster member to cluster member links to improve performance in mobile communication systems

• US 6,973,053 B1
• Filed: 09/12/2000
• Issued: 12/06/2005
• Est. Priority Date: 09/12/2000
• Status: Expired due to Term

• Current Assignee: Raytheon BBN Technologies Corp. (Rtx Corporation)
• Original Assignee: BBNT Solutions LLC (Rtx Corporation)
• Inventors: Kulik, Joanna, Manning, Keith W., Weinstein, Joseph J., Elliott, Brig Barnum, Passman, William S., Zavgren, John R.
• Primary Examiner(s): Phan, Man U.
• Application Number:
  US09/660,521
• Time in Patent Office: 1,911 Days
• Field of Search: 370233-252, 370312-342, 370410-412, 455445-450, 455/522, 455/571, 709201-227
• US Class Current: 370/310
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04W 40/08 based on transmission power
• CPC Class Codes: H04W 40/32 for defining a routing cluster membership
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communications system has stations arranged in clusters (1a, 1b and 1c) of communication member stations (CM2, CM3, CM6 and CM7), with one member station (CH1, CH4 or CH5) in each cluster being a head station for the cluster. Each member station (CM2, CM3, CM6 and CM7) communicates with the network through a cluster head station (CH1, CH4 or CH5). The cluster head stations (CH1, CH4 and CH5) communicate among other cluster head stations (CH1, CH4 and CH5). A mobile communications station (e.g., CM3) evaluates a beacon message received from a first member station (e.g., CM6) of the plurality of mobile stations through a transceiver 6. The station CM3 also determines whether to communicate with the first member station CM6 directly or to communicate with the first member station CM6 by forwarding messages through a cluster head station CH1 that is affiliated to the mobile communications station CM3.

Claims

1. A first mobile communications station configured for use in a communications network connecting at least one cluster of communications stations, wherein a cluster has a communications station operating as a cluster head for directing communications within and among the clusters, said first mobile communications station comprising:

an electronic memory circuit having network information stored therein;

a transceiver which transmits signals to and receives signals from the communications stations in the network; and

an electronic processor circuit configured to (i) determine the strength of a signal received from a second communications station through said transceivers, and (ii) determines whether to communicate with the second communications station directly or to communicate with the second communications station by routing messages through cluster head affiliated to said first mobile communications station based on the signal strength.

2. A first mobile communications station according to claim 1, wherein the determination of whether to communicate with the second communications station directly or to communicate with the second communications station by routing messages through a cluster head affiliated to first mobile communications station comprises evaluating network bandwidth.

3. A first mobile communications station according to claim 1, wherein the stored network information comprises received member beacon information.

4. A first mobile communications station according to claim 1, wherein said electronic processor circuit determines a communications route based on at least one of a transmission power level of an affiliated cluster head, a required transmission power level to transmit to the second communications station, node congestion of the affiliated cluster head, and bandwidth optimization.

30. A first mobile communications station according to claim 1, wherein the determination by said electronic processor circuit further comprises evaluating a signal from a cluster head affiliated with the first mobile communications station.

31. A first mobile communications station according to claim 30, wherein said electronic processor circuit evaluates an RSSI of the signal from the affiliated cluster head.

5. A first mobile communications station for use in a communications network connecting at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communications within and among the clusters, said first mobile communications station comprising:

an electronic memory circuit having network information stored therein;

a transceiver which transmits signals to and receives signals from mobile stations in the network; and

an electronic processor circuit configured to (i) determine a received signal strength indicator (RSSI) for a second communications station of the plurality of mobile stations based on the signal strength of a member beacon received from the second communications station through said transceiver, (ii) determines a RSSI for a cluster head affiliated with the mobile communication station based on the strength of a signal received by the mobile communication system through said receiver; and

(iii) communicates with the second communications station directly when the RSSI of the second communications station is greater than the RSSI of the affiliated cluster head plus an additional value.

6. A first mobile communications station according to claim 5, wherein the additional value comprises a fraction of a maximum RSSI of the affiliated cluster head.

7. A first mobile communications station according to claim 5, wherein the additional value comprises one-half of the maximum RSSI of the affiliated cluster head.

8. A first mobile communications station according to claim 5, wherein the second communications station and said mobile communications station are affiliated to a same cluster.

9. A first mobile communications station according to claim 5, wherein the second communications station and said mobile communications station are affiliated to a different cluster.

10. A first mobile communications station according to claim 5, wherein said electronic processor circuit determines at least one network cost and said mobile communications station directly communicates with the second communications station when the member beacon RSSI of the second communications station is greater than an RSSI of the affiliated cluster head plus an adjusted value minus the cost.

11. A first mobile communications station according to claim 5, wherein said electronic processor circuit executes a handshake protocol with the second communications station.

12. A first mobile communications station according to claim 11, wherein a communications link with the second communications station is maintained.

13. In a communications network including at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communication within and among the clusters, a method of operating a first mobile communications station comprising:

receiving a beacon message each from a second communications station and a cluster head affiliated with the first mobile communications station;

evaluating the signal strength of the beacon messages; and

determining whether to directly communicate with the second communications station or to communicate with the second communications station by forwarding messages through the cluster head affiliated with the first mobile communication station based on the evaluation of said beacon messages.

14. Computer executable code stored on a computer readable medium, the code for operating a first mobile communications station in a communications network which includes at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communication within and among the clusters, the computer executable code comprising:

code to evaluate the signal strength of a beacon received by the first mobile communications station from a second communications station;

code to direct messages, based on an evaluation of said evaluation code, from the first mobile communications device to the second communications station (i) through an affiliated cluster head, or (ii) directly to the second communications station.

15. In a communications network including at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communication within and among the clusters, a method for configuring the network comprising:

receiving a beacon issued by a first communications station at a second communication station;

determining a received signal strength indicator (RSSI) based on the strength of the beacon signal;

comparing the received signal strength indicator (RSSI) of the received beacon with a predetermined RSSI value; and

determining whether the second member station should communicate directly with the first communications station based at least in part on the comparison of said comparing step.

16. In a communications network including at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communication within and among the clusters, a method of operating a first communications station so as to route a message to a second communications station:

receiving a signal from the second communications station and determining a received signal strength (RSSI1) for the signal based on the strength of the received signal, and;

receiving a signal from an affiliated cluster head and determining a received signal strength (RSSI2) for the signal based on the strength of the received signal;

determining a value (X) representing a relationship between a maximum received signal strength and a received signal strength for a signal between the second communications station and the affiliated cluster head; and

transmitting a signal directly to the second communications station when;

RSSI1>

RSSI2−

X.

17. The method according to claim 16, wherein the message to be sent to the second communications station is relayed through the affiliated cluster head when the condition RSSI1>

RSSI2−

X is not met.

18. The method according to claim 16, wherein the signal from the second communications station is discarded when RSSI1 is below a predetermined value and the message to be sent to the first mobile station is relayed through the affiliated cluster head.

19. The method according to claim 16, wherein the relationship of said determining step is the maximum received signal strength minus the received signal strength for a signal between the second communications station and the affiliated cluster head.

20. The method according to claim 16, wherein the relationship of said determining step is approximated by the maximum received signal strength minus a fraction of the maximum received signal strength.

21. The method according to claim 16, wherein the relationship of said determining step is approximated by the maximum received signal strength minus one-half of the maximum received signal strength.

22. A first mobile communications station for use in a communications network connecting at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communications within and among the clusters, said mobile communications station comprising:

an electronic memory circuit having network information stored therein;

a transceiver which transmits signals to and receives signals from other communications stations in the network; and

an electronic processor circuit configured to determine whether a second communications station is within one radio hop from the first mobile communications station and to (i) communicate directly with the second communications station if the second communications station is determined to be within one radio hop;

or (ii) communicate with the second communications station through a cluster head if the second communications station is determined to not be within one radio hop from the first mobile communications station.

23. A first mobile communications station according to claim 22, wherein the second communications station and the first mobile communications station are affiliated to a same cluster.

24. A first mobile communications station according to claim 22, wherein the second communications station and the first mobile communications station are affiliated to different clusters.

25. A first mobile communications station according to claim 22, wherein said electronic processor circuit executes a handshake protocol with the second communications station.

26. A first mobile communications station according to claim 25, wherein a communications link with the second communications station is maintained.

27. A first mobile communications station according to claim 22, wherein the determination by said electronic processor circuit comprises evaluating a received member beacon from the second communications station.

28. A mobile communications station according to claim 27, wherein the determination by said electronic processor circuit further comprises evaluating a received signal strength indicator (RSSI) of the received member beacon.

29. A first mobile communications station according to claim 28, wherein said electronic processor circuit directs a message intended for the second communications station via an affiliated cluster head when the RSSI of the received member beacon from the second communications station is below a predetermined threshold value.

32. A first mobile communications station according to claim 27, wherein the determination by said electronic processor circuit further comprises evaluating a received signal strength indicator (RSSI) of the received member beacon.

36. Computer executable code stored on a computer readable medium according to claim 29 comprising:

code for evaluating a signal strength of beacon message received from the second communications station; and

wherein the determining of whether the second communication station is within one radio hop from the first mobile communications station is based on the signal strength evaluation.

33. In a communications network including at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communication within and among the clusters, a method of operating a first mobile communications station comprising:

determining whether a second communications station in the network is within one radio hop from the first mobile communications system;

communicating directly with the second communications station if the first mobile communications station is determined to be within one radio hop; and

communicating with the second communications station through a cluster head if the second communications station is determined to not be within one radio hop from the first mobile communications station.

34. A method of operating a communications station according to claim 33 comprising:

receiving a beacon message from the second communications station; and

evaluating the signal strength of the beacon message; and

wherein the determining of whether the second communication station is within one radio hop from the first mobile communications station is based on the signal strength evaluation.

35. Computer executable code stored on a computer readable medium, the code for operating a first mobile communications station in a communications network which includes at least one cluster of communications stations, wherein a cluster includes a cluster head for directing communication within and among the clusters, the computer executable code comprising:

code for determining whether the second communications station is within one radio hop from the communications station; and

code to direct messages (i) directly to the second communications station if the second communications station is within one radio hop of the first communications station and (ii) to the second communications station through an affiliated cluster head if the second communications station is not within one radio hop of the communications station.