Determining relative spatial information between vehicles

• US 8,041,469 B2
• Filed: 01/05/2005
• Issued: 10/18/2011
• Est. Priority Date: 01/05/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Kellum, Carroll C., Kukshya, Vikas, Parikh, Jayendra S., Chiz, Max H., Krishnan, Hariharan
• Primary Examiner(s): Tran; Khoi
• Assistant Examiner(s): Jen; Ian
• Application Number:
  US11/029,890
• Publication Number:
  US 20060149475A1
• Time in Patent Office: 2,477 Days
• Field of Search: 340/435, 340/436, 340/961, 340/903, 340/457, 340/357.1, 340/901, 701/300, 701/301, 701/207, 701/176, 701/215, 701/41
• US Class Current: 700/300
• CPC Class Codes: G01S 11/06 using intensity measurements
• CPC Class Codes: G01S 11/10 using Doppler effect

Abstract

A method for determining relative spatial information between a first vehicle and a second vehicle, the method including monitoring a communication channel at the first vehicle and receiving a current communication signal sent by the second vehicle on the communication channel. The current communication signal is received at a received power level. A relative position between the first vehicle and the second vehicle is calculated. Input to the calculating includes an actual or estimated transmitted power level, and the received power level.

Claims

1. A method for determining relative spatial information between a first vehicle and a second vehicle, the method comprising:

monitoring in a communication channel at the first vehicle;

a transmitter unit transmitting a communication signal originating from the second vehicle, wherein the communication signal is transmitted at a fixed power level;

receiving at the first vehicle the communication signal on the communication channel from the second vehicle, wherein the communication signal as received defines a current communication signal at a received power level; and

calculating a distance between the first vehicle and the second vehicle, wherein input to the calculating includes an actual or estimated transmitted power level and the received power level.

2. The method of claim 1 wherein the calculating is performed based on a wireless communication path loss model.

3. The method of claim 1 wherein the calculating is performed based on a past estimate of a wireless communication path loss model parameter.

4. The method of claim 1 wherein the calculating includes executing a free space path loss wireless communication model.

5. The method of claim 1 wherein the calculating includes executing a two-ray path loss wireless communication model.

6. The method of claim 1 wherein one or more of an earlier communication signal, the current communication signal, and a later communication signal includes an estimated path loss exponent value;

and wherein input to the calculating further includes the estimated path loss exponent value.

7. The method of claim 1 wherein the calculating a distance between the first vehicle and the second vehicle is performed in conjunction with a GNSS device.

8. The method of claim 1 wherein the first vehicle includes a GNSS device for determining a GNSS position of the first vehicle and wherein the input to the calculating further includes the GNSS position of the first vehicle.

9. The method of claim 1 wherein one ,or more of an earlier communication signal, the current communication signal and a later conununication signal includes a GNSS position of the second vehicle and wherein the input to the calculating further includes the GNSS position of the second vehicle.

10. The method of claim 9 wherein a path loss exponent value is determined in response to both a GNSS position of the first vehicle and the GNSS position of the second vehicle.

11. The method of claim 9 wherein a communication path loss model parameter is determined in response to a GNSS position of the first vehicle and to the GNSS position of the second vehicle.

12. The method of claim 1 wherein the first vehicle has access to a database of predefined communication parameters and the input to the calculating further includes one or more of the predefined communication parameters.

13. The method of claim 1 wherein the current communication signal is received by a receiver on the first vehicle.

14. The method of claim 1 further comprising transmitting the distance to one or more of an Active Safety system or a Driver Assistance system.

15. The method of claim 1 further comprising determining a range rate associated with the current communication signal, wherein input to the determining includes a Doppler shift associated with the current communication signal.

16. The method of claim 1 wherein input to the calculating includes first vehicle information.

17. The method of claim 16 wherein the first vehicle information is used to filter or smooth distance estimates.

18. The method of claim 16 wherein the first vehicle information includes one or more of speed, yaw rate, acceleration, object detection sensor data, and antenna model.

19. The method of claim 1 wherein one or more of an earlier communication signal, the current communication signal and a later communication signal includes second vehicle information.

20. The method of claim 19 wherein the second vehicle information is used to filter or smooth distance estimates.

21. The method of claim 19 wherein the second vehicle information includes one or more of speed, yaw rate, acceleration, object detection sensor data, and antenna model.

22. The method of claim 1 wherein the calculating a distance between thefirst vehicle and the second vehicle is utilized in conjunction with an other location determination or object detection system.

23. The method of claim 22 wherein the other location determination or object detection system is one or more of a radar, lidar, vision, magnetic, and a sonar based system.

24. The method of claim 1 wherein one or more of an earlier communication signal, the current communication signal and a later communication signal includes an estimate of the distance as calculated by the second vehicle.

25. The method of claim 1 wherein input to the calculating further includes an estimated communication parameter.

26. The method of claim 1 wherein one or more of an earlier communication signal, the current communication signal and a later communication signal includes an actual transmitted power level and the value of the estimated transmitted power level is set to the actual transmitted power level.

27. A system for determining relative spatial information between a first vehicle and a second vehicle, comprising:

a receiver on a first vehicle for monitoring a communication channel;

a transmitter on a second vehicle configured to transmit a communication signal; and

a processor for executing instructions to implement a method, the method including;

monitoring the communication channel at the first vehicle;

originating the communication signal from the second vehicle;

transmitting the communication signal from the second vehicle, wherein the communication signal is transmitted at a fixed power level;

receiving the communication signal from the second vehicle on the communication channel, wherein the communication signal as received defines a current communication signal at a received power level;

wherein the current communication signal includes estimated relative spatial information from the second vehicle;

calculating a relative position between the first vehicle and the second vehicle, wherein input to the calculating includes an actual or estimated transmitted power level and the received power level; and

comparing the calculated relative position to the estimated relative spatial information received from the second vehicle.

28. The system of claim 27 wherein the calculating is performed based on a wireless communication path loss model.

29. The system of claim 27 wherein the receiver is a wireless receiver.

30. The system of claim 27 wherein the method further includes transmitting the relative position to one or more of an Active Safety system and a Driver Assistance system.