DEVICE FOR ACTIVATING A VEHICLE FUNCTION

Abstract

A device for activating a vehicle function. The device being intended to be housed on board a vehicle and includes at least one ultra-wideband communication antenna and at least one near-field communication antenna in order to communicate with an item of portable equipment carried by a user. The function being activated based on a location of the item of equipment with respect to the vehicle and on an authentication of the item of equipment. The windings of the near-field communication antenna delimit a perimeter of a receptacle in which the ultra-wideband communication antenna is located.

Claims

1. A device for activating a vehicle function, the device being intended to be housed on board a vehicle and comprising at least one ultra-wideband communication antenna and at least one near-field communication antenna, comprising windings, in order to communicate with an item of portable equipment carried by a user, the vehicle function being activated based on a location of said item of equipment with respect to the vehicle and on an authentication of the item of equipment, the windings of the near-field communication antenna delimit a perimeter of a receptacle in which the ultra-wideband communication antenna is located.

2. The activation device as claimed in claim 1, further comprising two near-field communication antennas each surrounding an ultra-wideband communication antenna.

3. The activation device as claimed in claim 2, wherein the ultra-wideband communication antennas are arranged on either side of a center of the activation device.

4. The activation device as claimed in claim 1, wherein the near-field communication antenna and the ultra-wideband communication antenna are connected to a printed circuit and ground planes of said circuit are located on either side of the receptacle.

5. A door handle for a vehicle, comprising an activation device as claimed in claim 1.

6. A vehicle door, comprising an activation device as claimed in claim 1.

7. A door pillar, comprising an activation device as claimed in claim 1.

8. A motor vehicle, comprising an activation device as claimed in claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Further features and advantages of aspects of the invention will become more clearly apparent upon reading the following description. This description is purely illustrative and should be read in conjunction with the appended drawings, in which:

[0020] FIG. 1 is a diagram showing a motor vehicle door handle comprising an activation device according to an aspect of the invention,

[0021] FIG. 2 is a sectional view showing a housing comprising an activation device according to the prior art,

[0022] FIG. 3 is a sectional view showing a housing comprising an activation device according to an aspect of the invention,

[0023] FIG. 4 is a perspective view showing the activation device according to an aspect of the invention,

[0024] FIG. 5 is a graph showing an intensity of the electromagnetic field of the near-field communication antennas in the plane XY, with and without the ultra-wideband communication antennas,

[0025] FIG. 6 comprises five radiation patterns of the ultra-wideband communication antennas, in the reference frame of FIG. 4, at various frequencies with and without the near-field communication antennas.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] As explained above, the activation device D from the prior art with the near-field communication antenna A2 offset on one side of the device D considerably reduces the space allocated to the ultra-wideband communication antennas A1, A1 and the space allocated to the printed circuit 10.

[0027] An aspect of the invention therefore proposes an activation device D in which the NFC antenna B2 is located at the same location as a ULB antenna B1, and no longer offset on one side.

[0028] More specifically, according to an aspect of the invention, windings E1, E2 of the NFC antenna B2 define a receptacle L1 in the device D in which the ULB antenna B1 is located (cf. FIG. 3).

[0029] FIG. 3 shows a sectional view of the activation device D of an aspect of the invention in the plane ZY of the orthonormal reference frame (O, x, y, z), also illustrated in FIG. 3.

[0030] The device D is contained within a generally sealed housing B, and said device comprises a printed circuit 10 equipped with electronic components, as well as at least one ultra-wideband communication antenna B1, B1 and at least one near-field communication antenna B2, B2.

[0031] The device D may be integrated into a vehicle V door handle P, but also into the door itself, or into a door pillar M or into any bodywork element located next to an opening element of the vehicle, for example next to a rear trunk.

[0032] In the example illustrated in FIG. 3, the device D comprises, without limitation per se, two ULB antennas B1, B1 and two NFC antennas B2, B2.

[0033] Indeed, the applicant observed that two ULB antennas B1, B1 made it possible to obtain two radiation patterns that are complementary and that improve the detection of the item of portable equipment P within a predetermined area around the vehicle V.

[0034] Said NFC antennas B2, B2 and said ULB antennas B1, B1 are connected to the printed circuit 10, which comprises the means for controlling said antennas, that is to say the means for transmitting/receiving and the means for processing the data that are sent and received by said antennas, this being known to a person skilled in the art.

[0035] In the example illustrated in FIG. 3, the ultra-wideband communication antennas B1, B1 are located on either side of a center C of the device D.

[0036] This center C is located in the middle of the printed circuit 10 along the longitudinal axis Y.

[0037] Said ULB antennas B1, B1, in a manner known per se, are in the form of a copper surface, here, illustratively, in the shape of a diamond.

[0038] According to an aspect of the invention, the windings E1, E2 of an NFC antenna B2 delimit a perimeter that defines a receptacle L1 in which a ULB antenna B1 is located.

[0039] This may be seen in FIG. 3, the windings E1, E2 of the NFC antenna B2, in the sectional view, being in a rectangular shape and defining the contours of a rectangular receptacle L1 surrounding the ULB antenna B1. Similarly, the windings F1, F2 of the NFC antenna B2 delimit a rectangular receptacle L2 surrounding the ULB antenna B1.

[0040] In the 3D dimension, the windings E1, E2 extend along the transverse axis X (cf. FIG. 4).

[0041] In the example of FIG. 3, the windings E1, E2 of the NFC antenna B2 are rectangular in shape, but they may also be round, square or oval in shape.

[0042] Likewise, the shape of the ULB antennas B1, B1 in the shape of a diamond is in no way limiting.

[0043] Ground planes P1, P2, P1, P2 of the printed circuit 10 are located on each side of the receptacle L1, along the vertical axis Z.

[0044] Said ground planes avoid any electromagnetic disturbance between said NFC antennas B2, B2 and the ULB antennas B1, B1 with the electronic components of the printed circuit 10.

[0045] The applicant observed that the presence of the ULB antennas B1, B1 near the NFC antennas B2, B2 impacted the performance of the NFC antennas B2, B2, but that this impact was negligible.

[0046] This is illustrated in FIG. 5. The graph of FIG. 5 represents the electromagnetic field (in ampere/meter) along the longitudinal axis Y of the device D generated by the two NFC antennas B1, B1 in two configurations: [0047] a. A first configuration C1 in which the device D does not comprise any ULB antennas B1, B1, [0048] b. A second configuration C2, in which the device D comprises two ULB antennas B1, B1, each being arranged according to an aspect of the invention, that is to say surrounded by an NFC antenna B2, B2.

[0049] It becomes apparent from reading the graph of FIG. 5 that the field generated by the two NFC antennas B2, B2 propagates less far along the axis Z with the second configuration C2 than with the first configuration C1.

[0050] In other words, the detection range along the axis Z of the NFC antennas B2, B2 is reduced by the presence of the ULB antennas B1, B1, which disturb them.

[0051] However, it was observed by the applicant that this electromagnetic disturbance results in a loss of size of the detection zone of only a few millimeters and may be neglected.

[0052] On the other hand, the applicant observed that the presence of the NFC antennas B2, B2 around the ULB antennas B1, B1 improved the homogeneity of the electromagnetic field produced by said ULB antennas B1, B1.

[0053] This is illustrated in FIG. 6. FIG. 6 shows five radiation patterns with various emission frequencies of 3.1 GHZ, 5.5 GHZ, 6.5 GHZ, 8 GHZ and 10.6 GHz of a ULB antenna B1, in two configurations: [0054] a. A first configuration D1 without the presence of an NFC antenna B2 arranged according to an aspect of the invention, that is to say surrounding the ULB antenna B1, [0055] b. A second configuration D2, in which an NFC antenna B2 surrounds the ULB antenna B1, according to an aspect of the invention.

[0056] It becomes apparent from reading the five radiation patterns that, for frequencies equal to 3.1 GHZ, 6.5 GHZ and 8 GHZ, the radiation pattern of the ULB antenna B1 in the second configuration D2 is more homogeneous in the two directions Z and Y than the radiation pattern of said antenna in the first configuration D1.

[0057] For the frequency of 5.5 GHZ, the radiation patterns in the two configurations are very close, and there is almost no difference.

[0058] Only at the very high frequency of 10.6 GHz is the trend reversed, and the radiation pattern in the second configuration D2 is less homogeneous than the radiation pattern in the first configuration D1.

[0059] It thus became apparent to the applicant, and contrary to the prejudices of a person skilled in the art, that the proximity of the two types of antennas, NFC B2, B2 and ULB B1, B1, did not notably worsen the performance of the two types of antennas and, on the contrary, greatly improved the performance of the ULB antennas B1, B1 for certain frequencies.

[0060] Thus, by arranging the NFC antennas B2, B2 around the ULB antennas B1, B1 and no longer offset at one end of the device D, the space allocated for the printed circuit 10 and for the ULB antennas B1, B1 is larger than that which was present in the device from the prior art.

[0061] Moreover, with the activation device D according to an aspect of the invention, the ultra-wideband communication and/or detection area around the vehicle V is more homogeneous, this being a non-negligible advantage.

[0062] An aspect of the invention is particularly ingenious because it goes against the prejudices of a person skilled in the art, who would not have arranged two antennas of different types (NFC and ULB) close to one another because they would fear electromagnetic disturbances.