SYSTEM AND METHOD OF VEHICULAR WIRELESS COMMUNICATION USING AN INTEGRATED COORDINATING ACCESS POINT

• US 20090138196A1
• Filed: 11/08/2005
• Published: 05/28/2009
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: Toyota Motor Corporation, Regents of the University of California (University of California)
• Original Assignee: Toyota Motor Engineering & Manufacturing North America Incorporated (Toyota Motor Corporation), University of California Berkeley (University of California)
• Inventors: Laberteaux, Kenneth P.
• Granted Patent: US 7,970,540 B2
• Time in Patent Office: Days
• US Class Current: 701/213
• CPC Class Codes: G08G 1/096716 where the received information does not generate an automatic action on the vehicle control
• CPC Class Codes: G08G 1/096783 where the origin of the information is a roadside individual element
• CPC Class Codes: H04W 74/02 Hybrid access

Abstract

A system and method of vehicular wireless communication over a Dedicated Short Range Communication service band is provided. The system includes a vehicle having a navigation means, a processor, and a communication means for transmitting a message via a wireless communications link. The system includes a control channel for communicating a safety communication and a service channel for communicating a non-safety communication. The control channel is subdivided into a contention-free period having a group management interval, a service announcement interval and a safety exchange interval and a contention period having a non-safety service interval. The system further includes an integrated coordinating access point that operates in both the control channel and service channel. The method includes the steps of determining if the vehicle is within communications range of the region, determining if the vehicle is registered with the access point, and if the vehicle is within the communications range of integrated coordinating access point, determining if a current time is within the safety exchange interval, and transmitting the safety communication by each registered vehicle during the safety exchange interval at the predetermined time for each registered vehicle. The method further includes the steps of determining if the safety communication exchange by every registered vehicle is completed, and permitting the vehicle to leave the control channel if the safety communication exchange is complete, and determining if a current time is within a contention period, and transmitting the non-safety communication if the current time is within the contention period.

Claims

1. A method of vehicular wireless communication over a Dedicated Short Range Communication service band using an integrated coordinating access point, said method comprising the steps of:

dividing the service band into a control channel for transmitting a safety communication, and a service channel for transmitting a non-safety communication;

defining an integrated coordinating access point that is both a coordinating access point and a service access point that transmits and receives non-safety communications, and the integrated coordinating access point operates on both the control channel and the service channel;

subdividing the control channel into intervals of time, wherein one interval is a safety exchange interval in a contention-free period of time and each registered vehicle transmits a safety communication at predetermined time during the safety exchange interval, and the predetermined time is determined by the integrated coordinating access point;

determining if the vehicle is within communications range of an integrated coordinating access point service region;

determining if the vehicle is registered with the integrated coordinating access point, if the vehicle is within the communications range of the integrated coordinating access point, wherein the integrated coordinating access point maintains a list of registered vehicles, and registering the vehicle with the integrated coordinating access point if not registered;

determining if a current time is within the safety exchange interval in the contention-free period of time in the control channel, and transmitting the safety communication by each registered vehicle during the safety exchange interval at the predetermined time for each registered vehicle, if the current time is within the safety exchange interval of the contention-free period;

determining if the safety communication exchange by every registered vehicle is completed, and permitting the vehicle to leave the control channel if the safety communication exchange is complete; and

determining if a current time is within a contention period and transmitting the non-safety communication if the current time is within the contention period.

2. A method as set forth in claim 1 further including the step of:

communicating a safety communication on an ad hoc schedule if the vehicle is not within the integrated coordinating access point service region.

3. A method as set forth in claim 1 wherein the safety communication and non-safety communication are transmitted via a broadcast over the Dedicated Short Range Communication service band by a radio.

4. A method as set forth in claim 1 further including the step of determining if the vehicle is leaving the region, and removing the vehicle from the list of registered vehicles if the vehicle is leaving the region.

5. A method as set forth in claim 1 wherein said step of dividing the control channel into intervals further includes the steps of:

defining a group management interval and a service announcement interval within the contention-free period wherein the integrated coordinated access point communicates the available services during the service announcement interval of the contention-free period; and

defining a non-safety services interval in the service channel within a contention period, wherein the integrated coordinating access point provides services on the service channel during the contention period.

6. A method as set forth in claim 5, wherein said integrated coordinating access point periodically returns to the control channel from the service channel during the contention period.

7. A method as set forth in claim 1 wherein said step of registering the vehicle within the region further includes the steps of:

updating the registered vehicle list by adding the vehicle to the registered vehicle list if determined that the vehicle is entering the region, or removing the vehicle from the registered vehicle list if determined that the vehicle is leaving the region.

8. An system of vehicular wireless communication over a Dedicated Short Range Communication service band using an integrated coordinating access point within a region comprising:

a navigation means on the vehicle that is in communication with a global positioning system which includes a global positioning transceiver associated with the vehicle, and a global positioning signal transmitter in communication with the vehicle global positioning transceiver;

a processor on the vehicle that is in communication with said navigation means;

an input means in communication with said processor;

a user notification device operatively in communication with said navigation means for providing information to a vehicle operator;

a user manual input mechanism operatively in communication with said navigation means transmitting information from the vehicle operator;

a communication means operatively in communication with said navigation means for transmitting a message over a channel on the Dedicated Short Range Communication service band via a wireless communications link, wherein the channel is divided into a control channel for communicating a safety communication and a service channel for communicating a non-safety communication, and the control channel is further subdivided into a contention-free period and a contention period, and the contention-free period and is subdivided into a group management interval, a service announcement interval and a safety exchange interval of time and the contention period is subdivided into a non-safety service interval of time;

an integrated coordinating access point operatively in communication with the vehicle via said communications link within the integrated coordinating access point region, wherein the integrated coordinating access point service region is a geographic area containing the integrated coordinating access point and said integrated coordinating access point determines the predetermined time for each registered vehicle on a registration list maintained by the integrated coordinating access point within communications range of the access point to transmit a safety communication during the safety exchange interval.

9. A system as set forth in claim 8 wherein:

said region is a circular area with a integrated coordinating access point at a center of the region, and the integrated coordinating access point transmits a first signal in an access point service range, a second signal in an access point quiet range, a third signal in an access point poll range, a fourth signal in an access point safety exchange range, and a fifth signal in an access point service range;

a first vehicle is located within the region and transmits a signal in a vehicle safety message range; and

a second vehicle is located within the region and transmits a signal in a maximum interference range.

10. A system as set forth in claim 9 wherein the first signal transmitted by the integrated coordinating access point contains a start and a stop time of the next contention-free period.

11. A system as set forth in claim 8 wherein said vehicle transmits the safety communication on an ad-hoc basis when the vehicle is not registered with the access point.

12. A system as set forth in claim 8 wherein said integrated coordinating access point provides services on the service channel during the contention period.

13. A system as set forth in claim 12 wherein said integrated coordinating access point periodically returns to the control channel during the contention period.

14. A method of vehicular wireless communication over a Dedicated Short Range Communication service band using an integrated coordinating access point, said method comprising the steps of:

dividing the service band into a control channel for transmitting a safety communication, and a service channel for transmitting a non-safety communication;

defining an integrated coordinating access point that is both a coordinating access point and a service access point that transmits and receives non-safety communications, and the integrated coordinating access point operates on both the control channel and the service channel;

subdividing the control channel into intervals of time, wherein one interval is a safety exchange interval in a contention-free period of time and each registered vehicle transmits a safety communication at predetermined time during the safety exchange interval, and the predetermined time is determined by the integrated coordinating access point;

defining a group management interval and a service announcement interval within the contention-free period wherein the integrated coordinated access point communicates the available services during the service announcement interval of the contention-free period;

defining a non-safety services interval in the service channel within a contention period wherein the integrated coordinating access point provides services on the service channel during the contention period;

determining if the vehicle is within communications range of an integrated coordinating access point service region;

determining if the vehicle is registered with the integrated coordinating access point, if the vehicle is within the communications range of the integrated coordinating access point, wherein the integrated coordinating access point maintains a list of registered vehicles, and registering the vehicle with the integrated coordinating access point if not registered;

determining if a current time is within the safety exchange interval in the contention-free period of time in the control channel, and transmitting the safety communication by each registered vehicle during the safety exchange interval at the predetermined time for each registered vehicle, if the current time is within the safety exchange interval of the contention-free period;

determining if the safety communication exchange by every registered vehicle is completed, and permitting the vehicle to leave the control channel if the safety communication exchange is complete; and

determining if a current time is within a contention period, and transmitting the non-safety communication if the current time is within the contention period.

15. A method as set forth in claim 14 further including the step of:

communicating a safety communication on an ad hoc schedule if the vehicle is not within the integrated coordinating access point service region.

16. A method as set forth in claim 14 wherein the safety communication and non-safety communication are transmitted via a broadcast over the Dedicated Short Range Communication service band by a radio.

17. A method as set forth in claim 14 further including the step of determining if the vehicle is leaving the region, and removing the vehicle from the list of registered vehicles if the vehicle is leaving the region.

18. A method as set forth in claim 14, wherein said integrated coordinating access point periodically returns to the control channel from the service channel during the contention period.

19. A method as set forth in claim 14 wherein said step of registering the vehicle within the region further includes the steps of:

updating the registered vehicle list by adding the vehicle to the registered vehicle list if determined that the vehicle is entering the region, or removing the vehicle from the registered vehicle list if determined that the vehicle is leaving the region.