Communication method for locating a parked vehicle

• US 8,004,400 B2
• Filed: 11/05/2008
• Issued: 08/23/2011
• Est. Priority Date: 11/05/2008
• Status: Active Grant

• Current Assignee: Aptiv Technologies AG
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Miklik, Tom, Liem, Fiean, Partin, Dale L., Tieman, Craig A.
• Primary Examiner(s): Pham; Toan N
• Application Number:
  US12/290,969
• Publication Number:
  US 20100109914A1
• Time in Patent Office: 1,021 Days
• Field of Search: 340/539.13, 340/991, 340/988, 340/572.1, 340/989, 340/425.5, 340/426.26, 340/10.1, 340/825.36, 340/5.61
• US Class Current: 340/539.13
• CPC Class Codes: G08G 1/005 including pedestrian guidance indicator
• CPC Class Codes: G08G 1/14 indicating individual free spaces in parking areas
• CPC Class Codes: G08G 1/205 Indicating the location of the monitored vehicles as destination, e.g. accidents, stolen, rental

Abstract

A method of locating a parked vehicle that is equipped with a RKE system including a vehicle-installed RF communication module and a driver-borne wireless RF nomadic device such as a key fob involves installing a RFID tag in the nomadic device and a RFID interrogator in the vehicle. The driver depresses a button on the nomadic device to transmit a location request to the vehicle'"'"'s communication module, and the RFID interrogator in turn emits a RF interrogation signal to identify the RFID tag and determine its location relative to the vehicle. The communication module then transmits a compass bearing to the nomadic device, and an indicator of the nomadic device is activated to provide the driver with a bearing for locating the vehicle.

Claims

1. A method for locating a vehicle from a remote nomadic device, comprising the steps of:

providing a RF communication module and a RFID interrogator in the vehicle;

providing a RF transceiver, a RFID tag and an indicator in the nomadic device, said RF transceiver, RFID tag, and indicator powered by a nomadic device battery;

activating the RF transceiver of the nomadic device to transmit a location request to said communication module;

in response to receipt of the location request by the communication module, activating the RFID interrogator to interrogate said RFID tag and determine a direction and a range of said RFID tag relative to said vehicle;

activating the communication module to transmit a bearing to the RF transceiver of the nomadic device based on the determined relative direction and range of said RFID tag; and

activating the indicator of said nomadic device to indicate said bearing.

2. The method of claim 1, including the steps of:

providing an electronic compass in the nomadic device;

determining a heading to the vehicle relative to the nomadic device using the transmitted bearing and an output of the electronic compass; and

activating the indicator of said nomadic device to display the determined heading.

3. The method of claim 1, including the steps of:

determining a range from the vehicle to the nomadic device;

activating the communication module to transmit the determined range to the RF transceiver of the nomadic device; and

displaying the determined range on the indicator of the nomadic device.

4. The method of claim 1, including the steps of:

activating the RFID interrogator to interrogate said RFID tag and determine a range of said RFID tag relative to said vehicle in response to a detected proximity of the driver to the vehicle; and

activating a vehicle unlock function if the determined range is within a prescribed range.

5. The method of claim 1, including the steps of:

activating the RFID interrogator to interrogate said RFID tag and determine a range of said RFID tag relative to said RFID interrogator in response to occupant actuation of an engine start command; and

authorizing engine starting if the determined range is within a prescribed range.

7. The method of claim 4, including the steps of:

providing an electronic compass in the nomadic device;

determining a heading to the vehicle relative to the nomadic device using the transmitted bearing and an output of the electronic compass; and

activating the indicator of said nomadic device to display the determined heading.

8. The method of claim 4, including the steps of:

activating the RFID interrogator to interrogate said RFID tag and determine a range of said RFID tag relative to said RFID interrogator;

activating the communication module to transmit the determined range to the RF transceiver of the nomadic device; and

displaying the determined range on the indicator of the nomadic device.

6. A method for locating a vehicle from a remote nomadic device, comprising the steps of:

providing a RF communication module and a RFID interrogator in the vehicle;

providing a RF transceiver, a RFID tag and an indicator in the nomadic device;

detecting that the nomadic device has left the vehicle;

tracking the nomadic device to obtain bearing information, and periodically transmitting the bearing information to the RF transceiver of the nomadic device;

storing the transmitted bearing information in the nomadic device;

activating the RF transceiver of the nomadic device to transmit a location request to said communication module;

in response to receipt of the location request by the communication module, activating the RFID interrogator to interrogate said RFID tag and determine a direction and a range of said RFID tag relative to said vehicle;

retrieving the stored bearing information for display on the indicator of the nomadic device in response to subsequent driver activation of the nomadic device if the RFID tag is out of range of the RFID interrogator;

activating the communication module to transmit a bearing to the RF receiver of the nomadic device based on the stored bearing; and

activating the indicator of said nomadic device to indicate said bearing.