METHOD FOR DETECTING AN IDENTIFIER FOR STARTING A MOTOR VEHICLE

• US 20170243422A1
• Filed: 09/08/2015
• Published: 08/24/2017
• Est. Priority Date: 09/08/2014
• Status: Active Grant

• Current Assignee: Valeo Comfort And Driving Assistance
• Original Assignee: Valeo Comfort And Driving Assistance
• Inventors: Menard, Eric, Masson, Fabienne, Delaunay, Francis
• Granted Patent: US 10,169,941 B2
• Time in Patent Office: Days
• CPC Class Codes: B60R 2325/101 Bluetooth
• CPC Class Codes: B60R 2325/205 Mobile phones
• CPC Class Codes: B60R 25/209 Remote starting of engine
• CPC Class Codes: B60R 25/245 where the antenna reception area plays a role
• CPC Class Codes: G07C 2009/00547 starting ignition
• CPC Class Codes: G07C 2209/63 Comprising locating means for detecting the position of the data carrier, i.e. within the vehicle or within a certain distance from the vehicle
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04W 4/023 using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 52/04 TPC

Abstract

The present invention concerns a method (PR) for detecting an identifier (Id) for starting a motor vehicle (V), said motor vehicle comprising a first antenna (A1) and said identifier (Id) comprising a second antenna (A2). The method (PR) is characterised in that it comprises: —transmitting, by said first antenna (A1), a first Bluetooth Low Energy™ signal (Sg1) to said identifier (Id) at a nominal power (P1); —measuring the power (P1′) of said corresponding signal (Sg1′) received by the second antenna (A2) of said identifier (Id); —comparing said measured power (P1′) with a threshold power (Ps), said threshold power (Ps) corresponding to a threshold distance (ds) from said first antenna (A1) that is less than the radius (r1) of a circle (C1) inscribed within the passenger compartment (H) of the motor vehicle (V), said circle (C1) being centred on said first antenna (A1); —authorising the starting of the motor vehicle (V) if the measured power (P1′) is greater than or equal to said threshold power (Ps).

Claims

1. A method for detecting an identifier for starting a motor vehicle, said motor vehicle comprising a first antenna and said identifier comprising a second antenna, said method comprising:

transmitting, by said first antenna, a first Bluetooth Low Energy™

signal toward said identifier at a nominal power;

measuring the power of a corresponding signal received by the second antenna of said identifier;

comparing said measured power with a threshold power corresponding to a threshold distance from said first antenna which is smaller than a radius of a circle inscribed in the passenger compartment of the motor vehicle, said circle being centered on said first antenna; and

enabling the starting of the motor vehicle when the measured power is greater than or equal to said threshold power.

2. The detection method as claimed in claim 1, according to which the threshold distance is equal to twenty centimeters, plus or minus ten centimeters.

3. The detection method as claimed in claim 1, further comprising:

positioning said identifier at a reference position;

adjusting the second antenna of said identifier for use with the first antenna on the first use of said identifier with the motor vehicle, and/or on request.

4. The detection method as claimed in claim 3, wherein said first antenna is placed at a predefined distance from the reference position of the motor vehicle and the adjustment comprises:

transmitting, by of the first antenna, a first calibration signal at the nominal power toward the second antenna;

measuring the power of a corresponding reception signal received by said second antenna, and sending said measured power toward said first antenna;

comparing said measured power with a theoretical power corresponding to said predefined distance, using a regression curve of power as a function of distance;

determining whether there is an offset between said measured power and said theoretical power; and

when the offset exists, modifying the nominal power of the first transmitted Bluetooth Low Energy™

signal as a function of said offset, or modifying the threshold power as a function of said offset.

5. The detection method as claimed in claim 3, wherein, on the first use of the identifier with the motor vehicle, the method further comprises the display by the identifier on a screen of a message inviting the user of said identifier to position said identifier in the reference position and to launch said adjustment.

6. The detection method as claimed in claim 3, according to which said first antenna is placed at the reference position.

7. The detection method as claimed in claim 3, further comprising enabling the starting of the motor vehicle solely if the identifier is placed at the reference position of the motor vehicle.

8. The detection method as claimed in claim 1, wherein the identifier is a cellphone.

9. The detection method as claimed in claim 1, further comprising:

positioning said identifier at a reference position; and

adjusting the first antenna of said identifier for use with the second antenna.

10. The detection method as claimed in claim 9, wherein said first antenna is placed at a predefined distance from the reference position of the motor vehicle and the adjustment comprises:

transmitting, by the second antenna, a first calibration signal at the nominal power toward the first antenna;

measuring the power of said corresponding reception signal received by said first antenna;

comparing said measured power with a theoretical power corresponding to said predefined distance, using a regression curve of power as a function of distance;

determining whether there is an offset between said measured power and said theoretical power; and

when the offset exists, modifying the nominal power of the first transmitted Bluetooth Low Energy™

signal as a function of said offset, or modifying the threshold power as a function of said offset.

11. The detection method as claimed in claim 4, wherein a plurality of first calibration signals are sent and a plurality of power measurements are made, and the measured power compared with said theoretical power is equal to the mean of the measured powers lying within a range which depends on the standard deviation of the plurality of power measurements.

12. A system for detecting an identifier for starting a motor vehicle, said motor vehicle comprising a first antenna and a computer comprising a processing unit and said identifier comprising a second antenna and a processing unit, said system comprising:

said identifier; and

said first antenna, said identifier being configured for;

receiving a first Bluetooth Low Energy™

signal transmitted by said first antenna at a nominal power;

measuring the power of said corresponding signal received by the second antenna;

comparing said measured power with a threshold power corresponding to a threshold distance from said first antenna which is smaller than a radius of a circle inscribed in the passenger compartment of the motor vehicle, said circle being centered on said first antenna;

said first antenna of the motor vehicle being configured for;

transmitting a first Bluetooth Low Energy™

signal toward said identifier at a nominal power;

said computer being configured for enabling the starting of the motor vehicle if the measured power is greater than or equal to said threshold power.

14. The detection system as claimed in claim 12, wherein the threshold distance is equal to twenty centimeters, plus or minus ten centimeters.

15. The detection system as claimed in claim 12, wherein said identifier is adapted to be positioned at a reference position and said first antenna is adapted for calibrating the second antenna on a first use with the motor vehicle and/or on request.

16. The detection system as claimed in claim 15, wherein said first antenna is placed at a predefined distance from the reference position of the motor vehicle, and according to which, for the adjustment:

the first antenna is configured for;

sending a first calibration signal at the nominal power toward the second antenna;

the second antenna is configured for;

measuring the power of said corresponding reception signal received;

sending said measured power toward said first antenna;

the processing unit of the computer is configured for;

comparing said measured power with a theoretical power corresponding to said predefined distance, using a regression curve of power as a function of distance;

determining whether there is an offset between said measured power and said theoretical power;

when an offset exists, modifying the nominal power of the first transmitted Bluetooth Low Energy™

signal as a function of said offset, or modifying the threshold power as a function of said offset.

17. The detection system as claimed in claim 15, wherein said first antenna is placed at a predefined distance from the reference position of the motor vehicle, and according to which, for the adjustment:

the first antenna is configured for;

sending a first calibration signal at the nominal power toward the second antenna;

the second antenna is configured for;

measuring the power of said corresponding reception signal received;

the processing unit of the identifier is configured for;

comparing said measured power with a theoretical power corresponding to said predefined distance using a regression curve of power as a function of distance;

determining whether there is an offset between said measured power and said theoretical power (Pt);

when an offset exists, sending said offset to said first antenna;

modifying the nominal power of the first transmitted Bluetooth Low Energy™

signal as a function of said offset, or modifying the threshold power as a function of said offset.

18. The detection system as claimed in claim 12, wherein said second antenna is configured to adjust the first antenna.

19. The detection system as claimed in claim 18, wherein said first antenna is placed at a predefined distance from the reference position of the motor vehicle, and according to which, for the adjustment:

the second antenna is configured for;

transmitting a first calibration signal at the nominal power toward the first antenna;

the first antenna is configured for;

measuring the power of said corresponding reception signal received;

sending said measured power toward said second antenna;

the processing unit of the identifier is configured for;

comparing said measured power with a theoretical power corresponding to said predefined distance using a regression curve of power as a function of distance;

determining whether there is an offset between said measured power and said theoretical power;

when an offset exists, modifying the nominal power of the first transmitted Bluetooth Low Energy™

signal as a function of said offset, or modifying the threshold power as a function of said offset.

20. The detection system as claimed in claim 18, wherein said first antenna is placed at a predefined distance from the reference position of the motor vehicle, and according to which, for the adjustment:

the second antenna is configured for;

transmitting a first calibration signal at the nominal power toward the first antenna;

the first antenna is configured for;

measuring the power of said corresponding reception signal received;

the processing unit of the computer is also adapted for;

comparing said measured power with a theoretical power corresponding to said predefined distance using a regression curve of power as a function of distance;

determining whether there is an offset between said measured power and said theoretical power;

when an offset exists, modifying the nominal power of the first transmitted Bluetooth Low Energy™

signal as a function of said offset, or modifying the threshold power as a function of said offset.

13. A system for detecting an identifier for starting a motor vehicle, said motor vehicle comprising a first antenna and a computer comprising a processing unit and said identifier comprising a second antenna and a processing unit, said system comprising:

said identifier; and

said first antenna, said identifier being configured for;

receiving a first Bluetooth Low Energy™

signal transmitted by said first antenna at a nominal power;

measuring the power of said corresponding signal received by the second antenna;

said first antenna of the motor vehicle being configured for;

transmitting a first Bluetooth Low Energy™

signal toward said identifier at a nominal power;

said computer is configured for;

comparing said measured power with a threshold power corresponding to a threshold distance from said first antenna which is smaller than a radius of a circle inscribed in the passenger compartment of the motor vehicle, said circle being centered on said first antenna;

enabling the starting of the motor vehicle when the measured power is greater than or equal to said threshold power.