Collaborative multicast for dissemination of information in vehicular ad-hoc networks

• US 20070001869A1
• Filed: 06/29/2005
• Published: 01/04/2007
• Est. Priority Date: 06/29/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Hunzinger, Jason
• Granted Patent: US 7,333,026 B2
• Time in Patent Office: Days
• US Class Current: 340/903
• CPC Class Codes: G08G 1/092 Coding or decoding of the information
• CPC Class Codes: G08G 1/161 Decentralised systems, e.g. inter-vehicle communication
• CPC Class Codes: H04L 12/1854 with non-centralised forwarding system, e.g. chaincast

Abstract

A collaborative nomination algorithm is provided for disseminating information amongst a plurality of collaborating vehicles in an inter-vehicle communication network. The method includes: receiving an incoming vehicle communication message at a recipient vehicle from one of the collaborating vehicles; nominating one of the collaborating vehicles identified in the incoming vehicle communication message to broadcast a subsequent vehicle communication message; and transmitting an outgoing vehicle communication message from the recipient vehicle, where the outgoing vehicle communication message identifies the vehicle nominated to broadcast the subsequent vehicle communication message.

Claims

1. A method for disseminating information amongst a plurality of collaborating vehicles in an inter-vehicle communication network, comprising:

receiving an incoming vehicle communication message at a recipient vehicle from one of the other collaborating vehicles, where the incoming vehicle communication message identifies at least two of the collaborating vehicles;

nominating one of the collaborating vehicles identified in the incoming vehicle communication message to broadcast a subsequent vehicle communication message; and

transmitting an outgoing vehicle communication message from the recipient vehicle, where the outgoing vehicle communication message identifies the vehicle nominated to broadcast the subsequent vehicle communication message.

2. The method of claim 1 wherein the incoming vehicle communication message identifies the recipient vehicle as a next vehicle to broadcast the nominating communication message.

3. The method of claim 1 wherein the incoming vehicle communication message includes a reference section for communicating vehicle status information for one of the collaborating vehicles and a differential section for storing vehicle status information for the other collaborating vehicles, where the vehicle status information in the differential section is defines as a differential with the vehicle status information in the reference section.

4. The method of claim 1 wherein the step of nominating further comprises selecting a collaborating vehicle from which a vehicle communication message has not been received from for longest period of time.

5. The method of claim 1 wherein the step of nominating further comprises selecting at least one of the other vehicles identified in the incoming vehicle communication message as a backup to the nominated vehicle.

6. The method of claim 1 wherein transmitting the nominating communication message further comprises delaying a predetermined amount of time before transmitting the outgoing vehicle communication message.

7. The method of claim 6 wherein the predetermined amount of time is correlated to either a time at which the incoming vehicle communication message was received at the recipient vehicle or a time at which the incoming vehicle communication message was transmitted.

8. The method of claim 1 wherein transmitting an outgoing vehicle communication message further comprising providing vehicle status information for collaborating vehicles that are substantially similar to the vehicle status information for the recipient vehicle.

9. The method of claim 8 wherein similarity is based in part on a direction the collaborating vehicles are traveling in relation to the recipient vehicle.

10. The method of claim 1 wherein transmitting an outgoing vehicle communication message further comprising providing vehicle status information for collaborating vehicles having communicated with the recipient vehicle within a predefined time period.

11. The method of claim 1 wherein transmitting an outgoing vehicle communication message further comprising providing vehicle status information for collaborating vehicles whose vehicle status information has been updated within a predefined time period.

12. The method of claim 1 further comprises transmitting the nominating communication message over a wireless communication network.

13. The method of claim 1 wherein transmitting an outgoing vehicle communication message occurs upon expiration of a nomination timer which is set as follows:

T_N=T_N+pT_B, where T_N is a delay time from being nominated to transmitting a primary update message, T_B is a delay time from the primary update message to a first backup message transmission and each subsequent backup message transmission, and p is a designated backup number.

14. The method of claim 1 wherein transmitting an outgoing vehicle communication message occurs upon expiration of an update timer, where the update timer is correlated to a rate at which the recipient vehicle desires to receive information.

15. A data record for disseminating information amongst a plurality of collaborating vehicles in an inter-vehicle communication network, comprising:

a reference section for storing vehicle status information for a select collaborating vehicle, where the vehicle status information for the select collaborating vehicle serves as a reference for reporting vehicle status information for other collaborating vehicles; and

a differential section for storing vehicle status information for the other collaborating vehicles, where the vehicle status information for the other collaborating vehicles is a differential from the vehicle status information for the select collaborating vehicle.

16. The data record of claim 15 wherein the reference section includes an identifier for the select collaborating vehicle.

17. The data record of claim 15 wherein the select collaborating vehicle is designated as the vehicle broadcasting the data record across the inter-vehicle communication network.

18. The data record of claim 15 wherein the select collaborating vehicle is chosen in a manner that minimizes the size of the data record.

19. The data record of claim 15 wherein the differential section is further defined as an ordered array of data elements, where each data element contains vehicle status information for one of the other collaborating vehicles.

20. The data record of claim 19 wherein a first data element of the ordered array nominates one of the collaborating vehicles identified in the vehicle communication message to broadcast a subsequent vehicle communication message.

21. A method for disseminating information amongst a plurality of collaborating vehicles in an inter-vehicle communication network, comprising:

maintaining an update timer at a given collaborating vehicle, where the update timer is correlated to a rate at which the collaborating vehicle desires to receive information;

transmitting a vehicle communication message from the given collaborating vehicle upon expiration of the update timer; and

resetting the update timer upon receiving a vehicle communication message from one of the other collaborating vehicles.

22. The method of claim 21 further comprises nominating one of collaborating vehicles to broadcast a subsequent vehicle communication message and identify the nominated vehicle in the vehicle communication message transmitted from the given collaborating vehicle.

23. The method of claim 22 wherein the step of nominating further comprises selecting a collaborating vehicle from which a vehicle communication message has not been received from for longest period of time.

24. The method of claim 22 wherein the step of nominating further comprises selecting at least one of the other collaborating vehicles as a backup to the nominated vehicle.

25. The method of claim 21 wherein the transmitted vehicle communication message includes a reference section for communicating vehicle status information for one of the collaborating vehicles and a differential section for storing vehicle status information for the other collaborating vehicles, where the vehicle status information in the differential section is defined as a differential with the vehicle status information in the reference section.

26. A method for disseminating information amongst a plurality of collaborating vehicles in an inter-vehicle communication network, comprising:

receiving an incoming vehicle communication message at a recipient vehicle from one of the other collaborating vehicles, where the incoming vehicle communication message nominates one of the collaborating vehicles to broadcast a subsequent vehicle communication message and identifies the recipient vehicle as a backup transmitting vehicle;

resetting a nomination timer to a time that is longer than the time in which the recipient vehicle expects to receive the subsequent vehicle communication message from the nominated vehicle; and

transmitting a vehicle communication message from the recipient vehicle upon expiration of the nomination timer.

27. The method of claim 26 further comprises nominating one of collaborating vehicles to broadcast a subsequent vehicle communication message and identify the nominated vehicle in the vehicle communication message transmitted from the recipient vehicle.

28. The method of claim 26 wherein the transmitted vehicle communication message includes a reference section for communicating vehicle status information for one of the collaborating vehicles and a differential section for storing vehicle status information for the other collaborating vehicles, where the vehicle status information in the differential section is defined as a differential with the vehicle status information in the reference section.

29. The method of claim 26 wherein the nomination timer is set as follows:

T_N=T_N+pT_B, where T_N is a delay time from being nominated to transmitting a primary update message, T_B is a delay time from the primary update message to a first backup message transmission and each subsequent backup message transmission, and p is a designated backup number.