Determining relative spatial information between vehicles

1. A non-transitory computer-readable medium tangibly containing computer-executable instructions for determining relative spatial information between a first vehicle and a second vehicle, wherein execution of the instructions by a processing circuit causes the processing circuit to execute the steps of:

monitoring a communication channel at the first vehicle;

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

calculating at the first vehicle 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.

2. The non-transitory computer-readable medium as set forth in claim 1 , wherein calculating the relative position includes using a wireless communication path loss model.

3. The non-transitory computer-readable medium as set forth in claim 1 , wherein calculating the relative position is performed based on a past estimate of a wireless communication path loss model parameter.

4. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein calculating the relative position includes executing a free space path loss wireless communication model.

5. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein calculating the relative position includes executing a two-ray path loss wireless communication model.

6. The non-transitory computer-readable medium tangibly as set forth in 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 input to the calculating further includes the estimated path loss exponent value.

7. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein calculating the relative position between the first vehicle and the second vehicle is performed in conjunction with a Global Navigation Satellite System (GNSS) device.

8. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein execution of the instructions by the processing circuit causes the processing circuit to execute the step of transmitting the relative position to one or more of an Active Safety system and a Driver Assistance system.

9. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein execution of the instructions by the processing circuit causes the processing circuit to execute the step of 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.

10. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein:

input to calculating the relative position includes first vehicle information; and

the first vehicle information includes object detection sensor data.

11. The non-transitory computer-readable medium tangibly as set forth in claim 10 , wherein calculating the relative position includes using the first vehicle information to filter or smooth distance estimates.

12. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein:

one or more of an earlier communication signal, the current communication signal and a later communication signal includes second vehicle information; and

the second vehicle information includes at least one of speed and yaw rate.

13. The non-transitory computer-readable medium tangibly as set forth in claim 12 , wherein calculating the relative position includes using the second vehicle information to filter or smooth distance estimates.

14. The non-transitory computer-readable medium tangibly as set forth in 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.

15. The non-transitory computer-readable medium tangibly as set forth in claim 1 , input to calculating the relative position includes an estimated communication parameter.

16. The non-transitory computer-readable medium tangibly as set forth in 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.

17. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein the first vehicle includes a Global Navigation Satellite System (GNSS) device for determining a GNSS position of the first vehicle and wherein the input to calculating the relative position further includes the GNSS position of the first vehicle.

18. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein the first vehicle has access to a database of predefined communication parameters and the input to calculating the relative position further includes one or more of the predefined communication parameters.

19. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein execution of the instructions by the processing circuit causes the processing circuit to execute the step of receiving the current communication signal by a receiver on the first vehicle.

20. The non-transitory computer-readable medium tangibly as set forth in claim 1 , wherein execution of the instructions by the processing circuit causes the processing circuit to execute the step of determining a GNSS position of the first vehicle in response to the GNSS position of the second vehicle and to a path loss exponent value.