DEVICE FOR ACTIVATING A VEHICLE FUNCTION IN THE NEAR FIELD AND ULTRA WIDEBAND

Abstract

The invention relates to an activation device (D) for a vehicle function in near field (NFC) and ultra-wideband (ULB), intended to be mounted on a motor vehicle (V), comprising: an antenna (A) made up of a plurality of discontinuous windings (E) with two junction zones (J1, J2) thus forming a first part (A1) and a second part of the antenna (A2), means for controlling communication in near field (M1) of said antenna (A), first means for connecting (M4) between the windings of the two parts of the antenna comprising at least one inductance (L), means for controlling communication in near field of said antenna and the first means for connecting the two parts of the antenna forming a communication antenna in near field of said antenna, means for controlling communication in ultra-wideband (M2) of said antenna;of the second connection means (M3) between the windings of the same antenna part (A1) comprising at least one capacitor of value (C), the control means of said ultra-wideband antenna, the connection means (M3) and the two antenna parts forming an ultra-wideband dipole antenna, the activation device (D) being capable of communicating in the near field and in the ultra-wideband simultaneously. Figure for the abbreviation: Fig. 2;

Description

Title of the invention: DEVICE FOR ACTIVATING A VEHICLE FUNCTION IN THE NEAR FIELD AND IN ULTRA WIDEBAND technical field

[0001] The invention relates to a device for activating a vehicle function, in the near field and in ultra-wideband, embedded in a motor vehicle. The invention is particularly applicable to activation devices located in a vehicle door or door frame, preferably in the door handle, which allow the location, communication, and therefore authentication of a hands-free access device, such as a badge or smartphone, in a close area around the vehicle, in order to unlock the vehicle's doors without a physical key. Previous technique

[0002] In a motor vehicle, it is known to use vehicle function activation devices capable of detecting the presence of a user's hand or foot and thus enabling the locking or unlocking of all or part of the vehicle's openings, for example, the doors or the trunk. For example, detecting the presence of a user's hand on or in front of a door handle, coupled with the recognition of an identifier of a "hands-free" access device worn by that user, allows these openings to be locked and unlocked.

[0003] A so-called "hands-free" access system for a motor vehicle allows an authorized user to lock and / or unlock the vehicle's doors without having to physically press buttons on a key. To do this, the vehicle identifies a portable device, such as a badge, remote control, or even a key carried by the user. If the badge, remote control, or key is located within a predetermined area around or inside the vehicle and is identified as belonging to the vehicle, then the vehicle automatically locks / unlocks its doors according to the user's intention, without the user having to physically handle a key.

[0004] To do this, when the user approaches the vehicle, communication is established on a wireless communication link between the "hands-free" portable equipment, for example an electronic badge or a smart mobile phone, and the vehicle function activation device in order to authenticate said portable access equipment using its identifier.

[0005] Depending on the location of the portable equipment identified by the vehicle, in said location zones certain actions specific to said location zones are automatically carried out, unlocking / locking or prior activation of the interior lighting (also called "welcome lighting" in English).

[0006] Nowadays, it is increasingly common to use a mobile phone for authentication functions, thus avoiding the need for a dedicated electronic badge and reducing the number of devices required. It is therefore necessary to adapt the hands-free access and / or start system of a vehicle so that it can also function with a mobile phone equipped with communication standards, such as, for example, Ultra Wideband (UWB), Bluetooth Low Energy (BLE), Wi-Fi (wireless fidelity), or Near Field Communication (NFC). Ultra Wideband (UWB), in particular, is a radio modulation technique based on the transmission of very short pulses, often less than a nanosecond.Thus, bandwidth can reach very high values.

[0007] Ultra-wideband communication enables the portable device to be located and authenticated when it is within a predetermined radius of the vehicle, while near-field communication secures access by establishing very short-range communication between the vehicle and the access device. These two types of communication are therefore necessary and complementary to allow the user to unlock the vehicle's doors safely.

[0008] Approaching the access equipment close to the activation device (less than 2m) and recognizing the identifier received by the computer, coupled with the detection of the access equipment near the handle, allows the door to be locked or unlocked.

[0009] However, in a door handle, the space allocated for integrating an ultra-wideband elliptical monopole antenna and a coil for the near-field communication antenna on a vehicle printed circuit board is very limited. This integration cannot be achieved without compromise, by reducing the size of one or even both antennas.

[0010] The invention therefore proposes a vehicle function activation device using near field communication and ultra-wideband communication, overcoming the disadvantages of the prior art, more specifically allowing a saving of space compared to prior art devices. Description of the invention

[0011] The invention relates to a device for activating a vehicle function in the near field and in ultra-wideband, intended to be mounted on a motor vehicle, comprising: a. an antenna consisting of a plurality of discontinuous windings with two junction zones, thus forming a first and a second part of the antenna, b. control means for near-field communication of said antenna electrically connected to said antenna, c. of the first means of connection between the windings of the two antenna parts to the junction areas comprising at least one inductor, the at least one inductor connecting between a winding of the first part to a corresponding winding of the second part d. the near-field communication control means of said antenna and the first connection means and the two antenna parts forming a near-field communication antenna, e. ultra-wideband communication control means for said antenna electrically connected to said antenna at a junction point f. of the second means of connecting the windings of the same antenna part comprising at least one capacitor, the at least one capacitor connecting two windings of the same first or second antenna part, g. the control means for said ultra-wideband antenna, the connection means and the two antenna parts forming an ultra-wideband dipole antenna, the activation device being capable of communicating in near field and ultra-wideband simultaneously.

[0012] Preferably, the first part and the second part are symmetrical to each other along an axis passing through the junction zones.

[0013] Advantageously, at least one inductance of value adapted to a near-field communication frequency and has a value between 1 nH and 100 nH.

[0014] And at least one capacitor of value adapted to an ultra-wideband communication frequency and has a value between 10 pF and 100 pF.

[0015] The invention also relates to any vehicle door handle, door or motor vehicle, comprising a device according to any of the characteristics listed above. Brief description of the drawings

[0016] Other features and advantages of the invention will become apparent from the following description. This description is purely illustrative and should be read in conjunction with the accompanying drawings, in which:

[0017] [Fig-1]: [Fig.1] schematically represents a vehicle door handle comprising an activation device according to the invention,

[0018] [Fig.2]: [Fig.2] schematically represents an activation device according to the invention,

[0019] [Fig.3]: [Fig.3] schematically represents the first means of connection between the windings of the two antenna parts,

[0020] [Fig.4] : [Fig.4] schematically represents the second means of connection between the windings of the same part of the antenna. Description of the implementation methods

[0021] In [Fig.1], a door handle P of a motor vehicle V comprising an activation device D according to the invention is shown.

[0022] The activation device D according to the invention comprises a near-field communication antenna A, consisting of a plurality of windings E, located on a printed circuit board 10 (see [Fig. 2]). Near-field communication is communication at a frequency of 13.56 MHz over very short distances, on the order of a few tens of centimeters at most, the detection distance generally being between 0 and 10 cm.

[0023] The invention proposes that said antenna be modified in order to be able to communicate in ultra-wideband in the form of a dipole antenna, as will be explained below.

[0024] Ultra-wideband (UWB) is a radio modulation technique based on the transmission of very short pulses, often less than a nanosecond, over a wide frequency spectrum. This allows for very high bandwidths. UWB is generally considered to have a bandwidth-to-center frequency ratio of at least 20%, or a bandwidth of 250 MHz or more. In the United States, the FCC restricts the use of UWB to a bandwidth-to-center frequency ratio of 20% or more, or a bandwidth of 500 MHz or more.

[0025] The windings E have the singularity according to the invention of being discontinuous at the level of two junction zones J1, J2, thus forming two parts of the antenna, a first part Al and a second part A2 (cf. [Fig.2]).

[0026] Preferably, but by no means limitingly, as illustrated in [Fig.2], the first part Al and the second part A2 are symmetrical to each other along an axis YY' passing through the junction zones J1, J2.

[0027] The activation device D includes control means M1 for said near-field communication antenna, electrically connected to said antenna (see [Fig. 2]). The control means M1 include a transistor-type on / off switch or an input / output control of a microcontroller interface. This type of control means is known from the prior art.

[0028] According to the invention, the activation device D also includes first connection means M4 between the windings D of the two antenna parts Al, A2 to the junction areas J1, J2 comprising at least one inductance L of value adapted to the near field communication frequency, i.e. of value between, for example, InH and 100 nH.

[0029] Each winding E of a first antenna part Al is electrically connected to a corresponding winding E of the second antenna part A2 via said inductance L.

[0030] There is therefore as much inductance L as there are windings of the first part Al or of the second part of the antenna A2.

[0031] The inductances L thus connect the first antenna part Al to the second antenna part A2 for each winding E. The value of the inductance is such that the current from the control means Ml passes through the inductance thus electrically connecting the two antenna parts Al, A2 to form only one antenna A at the near field communication frequency.

[0032] The value of the inductance L is such that it blocks the passage of current at ultra-wideband communication frequencies.

[0033] The activation device D also includes ultra-wideband communication control means M2 electrically connected to the two antenna parts at at least one junction point J1 or J2. The control means M2 include a transistor-type on / off switch or a microcontroller interface input / output control. This type of control means M2 is known from the prior art.

[0034] It should be noted that the near-field communication control means M1 and the ultra-wideband communication control means M2 can be activated simultaneously. The activation device D thus designed according to the invention is capable of communicating in ultra-wideband and near-field simultaneously.

[0035] The activation device D comprises, according to the invention, second means of connections M3 between the windings E of the same part of antenna Al or A2 comprising at least a capacitance C of value adapted to an ultra-wideband ULB communication frequency.

[0036] Said capacitor C connects two windings E located close to each other of the same first or second part of antenna Al, A2.

[0037] Thus the windings E of the first part Al (respectively second part A2) are connected to each other two by means of a capacitor C.

[0038] The capacitance C has a value between, for example, lOpF and a few hundred pF, for example lOOpF.

[0039] The control means M2 of said ultra-wideband ULB antenna and the second connection means M3 between the windings of the same part of the antenna form an ultra-wideband dipole antenna.

[0040] The value of the capacitance C is indeed such that it allows the passage of current at the ultra-wideband (ULB) communication frequency, but blocks the passage of current at the near-field (NFC) communication frequency.

[0041] Of course, the inductances L can have different values ​​from each other and the capacitances C can have different values ​​from each other.

[0042] The invention is not limited to two symmetrical antenna parts Al, A2. The invention works even if the two antenna parts Al, A2 are not symmetrical.

[0043] It should be noted that the two antennas of different communication frequencies thus made by means of the activation device according to the invention operate simultaneously.

[0044] The control means for said near-field communication antenna M1 are activated simultaneously with the ultra-wideband communication control means M2. This makes the invention particularly interesting because there is no delay due to switching from one communication frequency to another.

[0045] The invention is therefore particularly ingenious because it makes it possible to obtain, from a modified near-field communication antenna, an ultra-wideband dipole communication antenna operating simultaneously with the near-field communication antenna.

Claims

Demands

1. Activation device (D) for a near-field vehicle function (NFC) and ultra-wideband (ULB), intended to be carried on a motor vehicle (V), characterized in that it comprises: a. an antenna (A) consisting of a plurality of discontinuous windings (E) with two junction zones (J1, J2) thus forming a first part (A1) and a second part of the antenna (A2), b. control means for near-field communication (M1) of said antenna (A) electrically connected to said antenna, c. of the first connection means (M4) between the windings of the two antenna parts (A1, A2) at the junction zones (J1, J2) comprising at least one inductor (L), the at least one inductor connecting between a winding of the first part (A1) to a corresponding winding of the second part (A2), d. the near-field communication control means (M1) of said antenna and the first connection means (M4) and the two antenna parts (A1, A2) forming a near-field communication antenna, e. the ultra-wideband communication control means (M2) of said antenna electrically connected to said antenna at a junction point (J1), f. of the second means of connection (M3) between the windings of the same antenna part (Al) comprising at least one capacitor of value (C), the at least one capacitor (C) connecting together two windings of the same first (Al) or the same second antenna part (A2), g. the control means (M2) of said ultra-wideband antenna, the connection means (M3) and the two antenna parts (A1, A2) forming an ultra-wideband dipole antenna, the activation device (D) being capable of communicating in near field and ultra-wideband simultaneously.

2. Activation device (D), according to the preceding claim, characterized in that the first part (A1) and the second part (A2) are symmetrical to each other along an axis (Y, Y') passing through the junction zones (J1, J2).

3. Activation device (D) according to any one of the preceding claims, characterized in that at least one inductance (L) has a value adapted to a near-field communication frequency and has a value between 1 nH and 100 nH.

4. Activation device (D) according to any one of the preceding claims characterized in that at least one capacity (C) of value, adapted to an ultra-wideband communication frequency and has a value between 1OpF and 1OOpF.

5. Vehicle door handle (P), characterized in that it comprises a device (D) according to any one of claims 1 to 4.

6. Vehicle door (P), characterized in that it comprises a device (D) according to any one of claims 1 to 4.

7. Motor vehicle (V), characterized in that it comprises a device (D) according to any one of claims 1 to 4.

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