METHOD FOR CHARACTERIZING A PORTABLE DEVICE BY WAY OF AN ANTENNA ON BOARD A MOTOR VEHICLE

• US 20140324252A1
• Filed: 12/12/2012
• Published: 10/30/2014
• Est. Priority Date: 12/13/2011
• Status: Active Grant

• Current Assignee: Continental Automotive France (Continental AG), Continental Automotive GmbH (Continental AG)
• Original Assignee: Continental Automotive France (Continental AG), Continental Automotive GmbH (Continental AG)
• Inventors: Kessler, Sebastien, Cheikh, Mohamed, Takacs, Alexandru
• Granted Patent: US 9,061,651 B2
• Time in Patent Office: Days
• US Class Current: 701/2
• CPC Class Codes: B60R 2325/103 Near field communication [NFC]
• CPC Class Codes: B60R 2325/105 Radio frequency identification data [RFID]
• CPC Class Codes: B60R 2325/205 Mobile phones
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user
• CPC Class Codes: B60R 25/245 where the antenna reception area plays a role
• CPC Class Codes: G06K 7/10 by electromagnetic radiation, e.g. optical sensing; by corpuscular radiation

Abstract

A method for characterizing, via at least one primary antenna on board a motor vehicle, a mobile device including a secondary antenna, approaching the vehicle in an indeterminate approach mode, the primary antenna intended to communicate with the secondary antenna, and generating a voltage across its terminals, the voltage being linked to an on-board system, includes:

• • measuring the voltage of the primary antenna over a series of predetermined time periods,
  • computing a voltage difference for each predetermined time period,
  • comparing the voltage difference with a previously stored value,
  • if the voltage difference is positive, the mobile device is of dielectric type, if it is negative, it is of metallic type,
  • if the voltage difference is zero over a predetermined time period above a threshold, the mobile device is in static approach mode, otherwise it is in dynamic approach mode.

Claims

1. A method for characterizing, by way of at least one primary antenna (13, 31) on board a motor vehicle (10), a mobile device (20) of indeterminate type comprising a secondary antenna (21) of indeterminate size, approaching said motor vehicle (10) in an indeterminate approach mode, said primary antenna (13, 31) being intended to communicate with the secondary antenna (21) of said mobile device (20), and generating a voltage (V) across its terminals, said voltage (V) being linked to an on-board system (11) of the motor vehicle (10), characterized in that said method of characterization comprises the following steps:

step 1;

measurement by the on-board system (11) of the voltage (V) across the terminals of the primary antenna (13, 31), over a series of predetermined time periods (Δ

t1, Δ

t2),

step 2;

computation by the on-board system (11) of a voltage difference (Δ

V) for each predetermined time period (Δ

t1, Δ

t2),

step 3;

comparison by the on-board system (11), for each predetermined time period (Δ

t1, Δ

t2), of the voltage difference (Δ

V) thus computed with a value previously stored in the memory and,

step 4;

if the voltage difference (Δ

V) is positive, then the mobile device (20) is of dielectric type,

if the voltage difference (Δ

V) is negative, then the mobile device (20) is of metallic type,

step 5;

once the type of the mobile device has been characterized,

if the voltage difference (Δ

V) is zero over a predetermined time period (Δ

t2), which is above a time threshold (Δ

th1) then the mobile device (20) is in static approach mode,

otherwise the mobile device (20) is in dynamic approach mode.

2. The method for characterizing a mobile device (20) as claimed in claim 1, characterized in that said method furthermore comprises the following steps:

step 2a;

in step 2, computation, by the on-board system (11), of the absolute value of a gradient (P) created by the voltage difference (Δ

V) for each predetermined time period (Δ

t1, Δ

t2),

step 3a;

in step 3, comparison, by the on-board system (11), of the absolute value of the gradient (P) thus computed with a value previously stored in the memory, previously referenced as a function of the size of the secondary antenna (21) of the mobile device (20) and,

step 4a;

in step 4, characterization of the size of the secondary antenna (21) of the mobile device (20) as a function of this comparison.

3. The method for characterizing a mobile device (20) as claimed in claim 1, characterized in that the primary antenna (13, 31) is a communication antenna of NFC type.

4. The method for characterizing a mobile device (20) as claimed in claim 1, characterized in that the mobile device (20) of dielectric type is a vehicle (10) access tag and/or the mobile device (20) of metallic type is a mobile phone.

5. The method for characterizing a mobile device (20) as claimed in claim 1, characterized in that the dynamic approach mode consists in the approach of the mobile device toward the primary antenna (13, 31) and/or the static approach mode consists in a fixed distance between the mobile device (20) and the primary antenna (13, 31).

6. The method of characterization as claimed in claim 4, characterized in that, if the mobile device (20) is a mobile phone in static approach mode, then said method furthermore comprises the following step:

step 6;

if the voltage (V) across the terminals of the primary antenna (13, 31) is below a threshold (V_3MIN), over a predetermined time period (Δ

ti), which is above a time threshold (Δ

th2), then the mobile phone is found in immediate proximity to the primary antenna (13, 31).

7. The method for characterizing a mobile device (20) as claimed in claim 2, characterized in that the primary antenna (13, 31) is a communication antenna of NFC type.

8. The method for characterizing a mobile device (20) as claimed in claim 2, characterized in that the mobile device (20) of dielectric type is a vehicle (10) access tag and/or the mobile device (20) of metallic type is a mobile phone.

9. The method for characterizing a mobile device (20) as claimed in claim 3, characterized in that the mobile device (20) of dielectric type is a vehicle (10) access tag and/or the mobile device (20) of metallic type is a mobile phone.

10. The method for characterizing a mobile device (20) as claimed in claim 2, characterized in that the dynamic approach mode consists in the approach of the mobile device toward the primary antenna (13, 31) and/or the static approach mode consists in a fixed distance between the mobile device (20) and the primary antenna (13, 31).

11. The method for characterizing a mobile device (20) as claimed in claim 3, characterized in that the dynamic approach mode consists in the approach of the mobile device toward the primary antenna (13, 31) and/or the static approach mode consists in a fixed distance between the mobile device (20) and the primary antenna (13, 31).

12. The method for characterizing a mobile device (20) as claimed in claim 4, characterized in that the dynamic approach mode consists in the approach of the mobile device toward the primary antenna (13, 31) and/or the static approach mode consists in a fixed distance between the mobile device (20) and the primary antenna (13, 31).