REFLECTOR FOR A RADIOFREQUENCY TRANSMISSION AND RECEPTION DEVICE DEDICATED TO THE DETECTION OF AN AUTOMATIC OPENING GESTURE ON A VEHICLE DOOR

Abstract

REFLECTOR FOR A RADIOFREQUENCY TRANSMISSION AND RECEPTION DEVICE DEDICATED TO THE DETECTION OF AN AUTOMATIC OPENING GESTURE OF A VEHICLE DOOR An aspect of the invention relates to a reflector (1), intended to be an integral part of a radiofrequency signal transmission and reception device for a gesture detector controlling the automatic opening of a motor vehicle door, said reflector (1) comprising: A reflection plate (2), capable of reflecting a radiofrequency beam, At least one mounting tab (3), each mounting tab (3) being formed in one piece with the reflection plate (2), and each mounting tab (3) being configured to be inserted into a respective hole through a thickness of a printed circuit board, and to be soldered to said printed circuit board at said hole, said printed circuit board comprising at least one radiofrequency antenna. Figure to be published with the abbreviation: Figure 1

Description

Title of the invention: REFLECTOR FOR A RADIOFREQUENCY TRANSMISSION AND RECEPTION DEVICE DEDICATED TO THE DETECTION OF AN OPENING GESTURE AUTOMATIC OPENING OF A VEHICLE TECHNICAL FIELD OF THE INVENTION

[0001] The present invention relates to a reflector, for a device for transmitting and / or receiving a radiofrequency signal, itself intended to form an integral part of a gesture detector controlling the automatic opening of a vehicle opening, in particular a motor vehicle. Another aspect of the invention relates to a device for transmitting and / or receiving a radiofrequency signal, intended to form an integral part of a gesture detector controlling the automatic opening of a motor vehicle opening, the device being provided with a reflector according to the invention.

[0002] The reflector and the device according to the invention apply, for example, to a vehicle equipped with a hands-free access system, so that a user of the vehicle can open a door or the trunk of the vehicle, simply by making a gesture, without physical contact with the vehicle or with a badge or other activation key. TECHNOLOGICAL BACKGROUND OF THE INVENTION

[0003] Numerous hands-free access systems are currently being developed which ensure the automatic opening of the vehicle's doors as soon as the user makes a predetermined movement with a body part near the vehicle. This predetermined movement can be detected by means of a radiofrequency type detector placed in a bumper, a rearview mirror, a B-pillar or a handle of the vehicle.

[0004] For example, in the case of opening a vehicle trunk, it is known to use gesture detection based on a radiofrequency signal transmission and reception device. Such a device is arranged in the rear bumper of the vehicle. This device is provided with two radiofrequency antennas, a first antenna emitting a radiofrequency beam in the direction rearward to the vehicle and a second antenna emitting a radiofrequency beam in the direction of the ground. Thus, when a user makes a foot movement crossing the two radiofrequency beams, the detector detects a desire to open the trunk of the vehicle and triggers the opening thereof.

[0005] However, problems with the openings sometimes occur. In fact, the radiofrequency beams overlap and are not precisely discriminated, so that the movement of a foot near the bumper is sometimes enough to open the trunk of the vehicle without the user having wanted it. The ratio of detection formed by a detection rate on a false detection rate is often too low. Summary of the invention

[0006] An objective of the invention is to propose a solution for reducing a false detection rate of a radiofrequency signal transmission and reception device as described in the introduction.

[0007] In this context, the invention thus relates, in its broadest sense, to a reflector, intended to form an integral part of a device for transmitting and receiving a radiofrequency signal for a gesture detector controlling the automatic opening of a motor vehicle opening, the reflector comprising: • A reflection plate, capable of reflecting a radiofrequency beam, • At least one fixing lug, each fixing lug being formed of a integral with the reflection plate, and each fixing tab being configured to be inserted into a respective hole passing through a thickness of a printed circuit board, and to be soldered to the printed circuit board at the hole, the printed circuit board comprising at least one radio frequency antenna.

[0008] This reflector is intended to be soldered to a printed circuit board equipped with a radiofrequency antenna. It makes it possible to shape a radiation pattern of the antenna, to make it more selective. This involves in particular concentrating the electromagnetic field in a desired coverage area, and consequently reducing the electromagnetic field outside this coverage area.

[0009] Thus, the reflector according to the invention increases the detection rate, reduces the false detection rate and avoids cases of an opening opening without the user having wanted it.

[0010] Furthermore, the reflector according to the invention is suitable for being integrated on a printed circuit board in a very simple manner, simply by pushing at least one of its fixing lugs into a corresponding hole in the printed circuit board, and by soldering the fixing lug onto the corresponding hole. This arrangement ensures very easy mechanical fixing of the reflector on the printed circuit board. This arrangement also makes it possible to orient the reflector in any desired orientation, relative to the plane of the printed circuit board. Thus, advantageously, the reflector, and more particularly the larger surface making up said reflector, is inclined at an angle relative to the plane of the printed circuit board. This inclination forms between the reflector and the plane of the printed circuit board an angle, for example, of between 10° and 80°, or even between 20° and 70°, or even between 34° and 55°.

[0011] The reflector according to the invention can be entirely constituted by the reflection plate and at least one fixing lug.

[0012] In addition to the characteristics which have just been mentioned in the preceding paragraph, the reflector according to this aspect of the invention may have one or more additional characteristics among the following, considered individually or according to all technically possible combinations.

[0013] According to a non-limiting aspect of the invention, the reflection plate has at least one notch passing through the reflection plate over its entire thickness.

[0014] According to a non-limiting aspect of the invention, the reflection plate is metallic.

[0015] Another aspect of the invention relates to a device for transmitting and receiving radio frequency signal, for a gesture detector controlling the automatic opening of a motor vehicle door, the device comprising: • A printed circuit board, equipped with at least one radiofrequency antenna, and crossed by at least one orifice; and • At least one reflector according to any one of the aforementioned aspects of the invention, at least one fixing lug of each at least one reflector being inserted inside a respective hole in the printed circuit board, and soldered to the printed circuit board at the hole.

[0016] According to a non-limiting aspect of the invention, the at least one reflector comprises a main surface, inclined at an angle relative to the plane of the printed circuit board, with an angle of inclination which is between 20° and 70°.

[0017] According to a non-limiting aspect of the invention, the printed circuit board is provided with a first face and a second face facing each other, one of the first or second faces being provided with a first radiofrequency antenna, the device further comprising a first reflector according to any one of the aforementioned aspects of the invention, each fixing lug of the first reflector being inserted into a respective orifice passing through a thickness of the printed circuit board and being welded to the printed circuit board at the orifice, the reflection plate of the first reflector being facing the first face.

[0018] According to a non-limiting aspect of the invention, the device further comprises a second reflector according to any one of the aforementioned aspects of the invention, each fixing lug of the second reflector being inserted into a respective orifice passing through the thickness of the printed circuit board and being welded to the printed circuit board at the orifice, the reflection plate of the second reflector being opposite the second face.

[0019] According to a non-limiting aspect of the invention, the first reflector and the second reflector frame the first radiofrequency antenna.

[0020] According to a non-limiting aspect of the invention, • The printed circuit board is provided with at least two radio frequency antennas; and • The device comprises at least two sets of reflector(s), where each set of reflector(s) comprises at least one reflector according to any one of the aforementioned aspects of the invention, and where each set of reflector(s) is associated with a respective one of the at least two radiofrequency antennas.

[0021] In use, at least one reflection tab of each at least one reflector is inserted within a respective one hole in the printed circuit board, and soldered to said printed circuit board at said hole.

[0022] The sets of reflectors are configured so as to improve the distinction between the respective radiation patterns associated with each of the radiofrequency antennas, in comparison with an identical device without the reflectors. In particular, the sets of reflectors are configured to increase a difference between a maximum radiation of one radiofrequency antenna and the radiation of the other radiofrequency antenna in the same direction. Where appropriate, the second set of reflectors makes it possible to create a shadow zone between the radiation from the two antennas, to further improve the separation between their respective radiations.

[0023] According to a non-limiting aspect of the invention, • the printed circuit board is provided with a first face and a second face facing each other, one of said first or second faces being provided with a first radiofrequency antenna, the device further comprising a first reflector according to any one of the aforementioned aspects of the invention, each fixing lug of the first reflector being inserted into a respective orifice passing through a thickness of the printed circuit board and being welded to the printed circuit board at the orifice, the reflection plate of the first reflector being facing the first face; • The device further comprises a second reflector according to any one of the aforementioned aspects of the invention, each fixing lug of the second reflector being inserted into a respective orifice passing through the thickness of the printed circuit board and being soldered to the printed circuit board at the orifice, the reflection plate of the second reflector being opposite the second face; and • one of the first or second faces of the printed circuit board is provided with a second radiofrequency antenna, the device further comprises a third reflector according to any one of the aforementioned aspects of the invention, each fixing lug of the third reflector being inserted into a respective orifice passing through the thickness of the printed circuit board and being welded to the printed circuit board at the orifice, the plate of reflection of the third reflector being opposite the first face or the second face.

[0024] According to a non-limiting aspect of the invention, the printed circuit board comprises a ground plane, each fixing lug being electrically connected to the ground plane.

[0025] According to a non-limiting aspect of the invention, the printed circuit board comprises a ground plane, the ground plane covering the first radiofrequency antenna.

[0026] According to a non-limiting aspect of the invention, the printed circuit board comprises a ground plane, the ground plane covering the second radiofrequency antenna.

[0027] Another aspect of the invention relates to a gesture detector for controlling the automatic opening of a motor vehicle opening, comprising: • A device according to any of the aforementioned aspects of the invention; and • At least one computer, configured to receive an input signal in originating from at least one radiofrequency antenna, to process this signal so as to detect a predetermined gesture made by a human operator, and to generate an instruction to open the motor vehicle opening when a predetermined gesture is detected.

[0028] The invention and its various applications will be better understood upon reading the following description and examining the accompanying figures. BRIEF DESCRIPTION OF THE FIGURES

[0029] The figures are presented for information purposes only and in no way limit the invention.

[0030] [Fig. 1] shows a side view of a reflector, according to a non-limiting aspect of the invention.

[0031] [Fig.2] is a front view of the reflector shown in [Fig.l].

[0032] [Fig.3] illustrates another non-limiting example of embodiment of a reflector according to the invention.

[0033] [Fig.4] [Fig.4] illustrates a non-limiting exemplary embodiment of a device for transmitting and receiving a radiofrequency signal for a gesture detector controlling the automatic opening of a motor vehicle door, according to one aspect of the invention.

[0034] [Fig.5] shows a different view of the radio frequency signal transmitting and receiving device illustrated in [Fig.4]

[0035] [Fig.6] shows a radiation pattern of radiofrequency beams emitted by the device illustrated in Figures 4 and 5.

[0036] [Fig.7] illustrates another non-limiting example embodiment of a device for transmitting and receiving a radiofrequency signal for a gesture detector controlling the automatic opening of a motor vehicle door, according to one aspect of the invention.

[0037] [Fig.8] illustrates a different non-limiting example of embodiment of a device transmission and reception of radiofrequency signal for a gesture detector controlling the automatic opening of a motor vehicle door, according to one aspect of the invention.

[0038] [Fig.9] shows a gesture detector to control the automatic opening of a motor vehicle opening according to one aspect of the invention.

[0039] [Fig. 10] illustrates a gesture detector for controlling the automatic opening of a motor vehicle opening according to another aspect of the invention. DETAILED DESCRIPTION

[0040] Unless otherwise specified, the same element appearing in different figures has a single reference.

[0041] Figures 1 and 2 show an exemplary embodiment of a reflector 1 according to one aspect of the invention, this reflector 1 being intended to form an integral part of a device for transmitting and receiving a radiofrequency signal for a gesture detector controlling the automatic opening of a motor vehicle opening. More particularly, [Fig. 1] is a profile view of this reflector 1 and [Fig. 2] is a front view of the reflector 1.

[0042] The reflector 1 consists of a reflection plate 2 for a radiofrequency beam. This reflection plate 2 here has three flat parts, a first part 2a, a second part 2b and a third part 2c. In this non-limiting example embodiment, the reflection plate 2 forms a Z. In order to reflect the radiofrequency beam, this reflection plate 2 may be made of metal, for example aluminum.

[0043] As illustrated in [Fig.2], and in a non-limiting manner, the reflector 1 is furthermore made up of three fixing lugs 3 formed in one piece with the reflection plate 2. Each fixing lug 3 is arranged to be positioned in a respective orifice of a printed circuit board, and soldered in said orifice. In a non-limiting manner, each of the fixing lugs may be planar and have a width of between 0.2 mm and 1.0 mm, for example 0.5 mm, and a length of between 0.2 mm and 2 mm.

[0044] In this embodiment, the second part 2b forms, when the reflector 1 is secured to a printed circuit board by means of the fixing lugs 3, a main surface, inclined at an angle relative to the plane of the printed circuit board, with an angle of inclination which is between 20° and 70°. This main surface 2b forms the largest flat surface among several surfaces 2a, 2b, 2c making up the reflector 1.

[0045] It should be noted that the printed circuit board is provided with a radiofrequency antenna. The reflection plate 2 thus forms, once mounted on the printed circuit board, a reflective barrier for a radiofrequency beam emitted by the radiofrequency antenna. Throughout the text, a radiofrequency beam designates a beam of electromagnetic rays whose carrier frequency is between 30 MHz and 300 GHz. Preferably, said frequency is between 3 GHz and 100 GHz, for example centered on approximately 24 GHz, or approximately 77 GHz, or approximately 81 GHz, or approximately 60 GHz. Advantageously, the radiofrequency beam is a UWB (ultra-wide band) signal whose frequency spectrum extends from 3 GHz to 10 GHz. Alternatively, the frequency spectrum may extend from 77 GHz to 81 GHz.

[0046] Here, but in a non-limiting manner, the reflection plate 2 also has two notches 4. Each notch 4 advantageously passes through the entire thickness e2 of the reflection plate 2. When the reflection plate 2 is soldered to the printed circuit board, these notches 4 are arranged opposite conductive tracks on the printed circuit board, in order to avoid any electromagnetic disturbance. Here, and advantageously, each notch 4 extends from an edge of the reflection plate 2.

[0047] In a different implementation not shown, each of the notches 4 passes through only a part of the thickness of the reflection plate 2.

[0048] [Fig. 3] is a side view of another embodiment of a reflector 1 for a radiofrequency signal transmission and reception device for a gesture detector controlling the automatic opening of a motor vehicle opening. In this embodiment, the reflection plate 2 is curved.

[0049] [Fig. 4] illustrates a non-limiting exemplary embodiment of a device for transmitting and receiving a radiofrequency signal for a gesture detector controlling the automatic opening of a motor vehicle opening according to one aspect of the invention. This device 5 can be used for detecting a particular gesture of the user's foot making it possible to control an automatic opening of the vehicle's trunk. [Fig. 5] illustrates a different view of this exemplary embodiment.

[0050] The device 5 comprises a printed circuit board 6 comprising a first face 7 and a second face 8 parallel to each other.

[0051] The first face 7 is provided with a first radiofrequency antenna 9, for example of the VIVALDI type.

[0052] The device 5 further comprises a first reflector 1a. Each of the fixing lugs 3 of the first reflector 1a is arranged in a respective orifice 10 passing through a thickness e6 of the printed circuit board 6. Here, but in a non-limiting manner, the orifices 10 and the fixing lugs 3 pass through the entire thickness of the printed circuit board. printed circuit board 6. In variants not shown, the orifices 10 and the fixing lugs 3 pass through only part of the total thickness of the printed circuit board 6. In this example, the fixing lugs 3 are soldered to the second face 8 of the printed circuit board 6. In order to facilitate soldering, the internal wall of the orifices 10 can be metallized.

[0053] It should also be noted that the reflection plate 2 of the first reflector 1a extends opposite the first antenna 9 and is opposite the first face 7 of the printed circuit board 6.

[0054] The device 5 comprises a second reflector 1b. Each of the fixing lugs 3 of the second reflector 1b is arranged in a metallized orifice 10 passing through the thickness e6 of the printed circuit board 6. In this example, the fixing lugs 3 are welded to the first face 7 of the printed circuit board 6.

[0055] It should also be noted that the reflection plate 2 of the second reflector 1b extends opposite the first antenna 9 and is opposite the second face 8 of the printed circuit board 6.

[0056] In this exemplary embodiment, the first reflector 1a and the second reflector 1b surround the first radiofrequency antenna 9. Thus, the radiofrequency beam emitted by the first radiofrequency antenna 9 is oriented and constrained by the reflection plates 2 of the first and second reflectors 1a, 1b.

[0057] In this embodiment, the first face 7 of the printed circuit board 6 is provided with a second radiofrequency antenna 11, for example of the PATCH type.

[0058] The device 5 further comprises a third reflector 1e. Each of the fixing lugs 3 of the third reflector 1e is arranged in a metallized orifice 10 passing through the thickness e6 of the printed circuit board 6. In this example, the fixing lugs 3 are welded to the second face 8 of the printed circuit board 6.

[0059] It should also be noted that the reflection plate 2 of the third reflector 1c extends in an offset manner relative to the second radiofrequency antenna 11 and is opposite the first face 7 of the printed circuit board 6.

[0060] The printed circuit board 6 further comprises a ground plane, not specifically shown, which may extend in particular with regard to the second antenna 11.

[0061] Thus, the radiofrequency beam emitted by the second radiofrequency antenna 11 is oriented and constrained by the reflection plate 2 of the third reflector 1c (as well as by the ground plane, if applicable).

[0062] Furthermore, the reflection plate 2 of the third reflector 1a has two notches 4 passing through its thickness e2. Each of these notches 4 is arranged opposite a respective conductive track 13 that the printed circuit board 6 comprises. This arrangement makes it possible to avoid a risk of electromagnetic interference.

[0063] Thanks to the first, second and third reflectors 1a, 1b, 1c, the radio beam frequency emitted by the first radiofrequency antenna 9 and the radiofrequency beam emitted by the second radiofrequency antenna 11 do not overlap. This feature makes it possible to effectively discriminate a particular gesture. [Fig.6] illustrates this advantage.

[0064] More particularly, [Fig.6] illustrates a radiation diagram of a radiofrequency beam emitted by the first radiofrequency antenna 9 and of a radiofrequency beam emitted by the second radiofrequency antenna 11.

[0065] More particularly, • Curve Cl illustrates the radiation pattern on the YOZ plane of a radiofrequency beam emitted or received by a first radiofrequency antenna 9 of a device according to the state of the art, which differs from the device of figures 4 and 5 only in that the radiofrequency beam is not constrained by any reflector; • Curve C2 illustrates the radiation pattern on the YOZ plane of a radiofrequency beam emitted or received by the second radiofrequency antenna 11 of the device according to the state of the art, which differs from the device of FIGS. 4 and 5 only in that the radiofrequency beam is not constrained by any reflector; • Curve C3 illustrates the radiation pattern of a radiofrequency beam emitted or received by the first radiofrequency antenna 9 of a device 5 as illustrated in FIGS. 4 and 5, the radiofrequency beam being constrained by the first and second reflectors 1a, 1b; • Curve C4 illustrates the radiation pattern of a radiofrequency beam emitted or received by the second radiofrequency antenna 11 of a device 5 as illustrated in Figures 4 and 5, the radiofrequency beam being constrained by the third reflector 1e (and the ground plane, if applicable).

[0066] It can thus be seen that in a YOZ plane, for an angle of -50 degrees, the difference in gain between the radiation of the first radiofrequency antenna 9 and the radiation of the second radiofrequency antenna 11 of a device according to the state of the art is 1 IdB. Here, the YOZ plane extends orthogonal to the plane of the printed circuit board.

[0067] For this same angle, the difference in gain between the radiation of the first radiofrequency antenna 9 and the radiation of the second radiofrequency antenna 11 of a device 5 according to the invention is 23 dB. This difference is explained by the presence of the first, second and third reflectors 1a, 1b, 1c. The two beams are thus better discriminated so that the detection accuracy of the device 5 is increased. In addition, thanks to the reflector 1c, a so-called shadow zone (radiation attenuated to -15dB) is created in the angular range between 25° and 55°.

[0068] [Fig. 7] illustrates another non-limiting exemplary embodiment of a device 5 according to one aspect of the invention. With this configuration, only two reflectors 1a and 1b are used on the first antenna. No reflector is positioned opposite the second antenna. Thus, the secondary radiation of the first antenna is reduced, but does not have a shadow zone created between the radiation of the two antennas.

[0069] The device 5 comprises a printed circuit board 6 comprising a first face 7 and a second face 8 parallel to each other.

[0070] The first face 7 is provided with a first radiofrequency antenna 9.

[0071] The device 5 further comprises a first reflector 1a. The reflection plate 2 of the first reflector 1a extends opposite the first antenna 9 and faces the first face 7 of the printed circuit board 6.

[0072] The device 5 also comprises a second reflector 1b. The reflection plate 2 of the second reflector 1b extends opposite the first antenna 9 and faces the second face 8 of the printed circuit board 6.

[0073] [Fig. 8] illustrates a different non-limiting example of embodiment of a device 5 for detecting an automatic opening gesture of a vehicle opening according to one aspect of the invention.

[0074] The device 5 comprises a printed circuit board 6 comprising a first face 7 and a second face 8 parallel to each other.

[0075] The first face 7 is provided with a first radiofrequency antenna 9.

[0076] The sensor 5 further comprises a first reflector 1a. The reflection plate 2 of the first reflector 1a extends opposite the first antenna 9 and faces the first face 7 of the printed circuit board 6.

[0077] The printed circuit board 6 comprises a ground plane, not specifically shown, which may extend in particular with regard to the first radiofrequency antenna 9.

[0078] [Fig.9] shows a gesture detector 14 for controlling the automatic opening of a motor vehicle door, comprising: • a device 5 conforming to the device 5 illustrated in [Fig.7]; and • at least one calculator 15, configured to receive as input a signal in originating from the at least one radiofrequency antenna 9, to carry out processing of this signal so as to detect a predetermined gesture made by a human operator, and to generate an instruction for opening a motor vehicle opening when a predetermined gesture is detected. As illustrated in [Fig.9], this calculator 15 can be arranged on the printed circuit board 6.

[0079] In a different embodiment illustrated in [Fig.10], this calculator 15 comprises first data processing means 15a integral with the printed circuit board 6 and second data processing means 15b external to the printed circuit board 6. These second data processing means 15b can be formed by a vehicle control unit (better known by the acronym VCU for Vehicle Control Unit in English).

[0080] It should be noted that a person skilled in the art is able to provide different variations to the aforementioned aspects of the invention, for example by modifying the shape of the reflection plate that the reflector comprises and / or by modifying the number of fixing lugs.

[0081] Furthermore, the examples described are limited to the opening of a trunk, it is understood that the reflector 1, the device 5 and the detector 14 according to the invention can be applied to any type of opening of a vehicle.

Claims

Claims

1. Device (5) for transmitting and receiving a radiofrequency signal, for a gesture detector controlling the automatic opening of a motor vehicle opening, said device (5) comprising: - A printed circuit board (6), crossed by at least one orifice (10) and provided with a first face (7) and a second face (8) facing each other, one of said first or second faces (7, 8) being provided with a first radiofrequency antenna (9); and - At least one reflector (1), provided with a reflection plate (2) capable of reflecting a radiofrequency beam and at least one fixing lug (3), each fixing lug (3) being formed in one piece with the reflection plate (2), at least one fixing lug (3) of each at least one reflector (1) being inserted inside a respective orifice (10) of the printed circuit board (6), and soldered to said printed circuit board (6) at said orifice (10);the device (5) being characterized in that: - the at least one reflector includes a first reflector (1a), the reflection plate (2) of which extends opposite the first face (7) of the printed circuit board (6), and - the at least one reflector further includes a second reflector (1b), the reflection plate (2) of which extends opposite the second face (8) of the printed circuit board (6).;

2. Device (5) according to claim 1, characterized in that the reflection plate (2) of at least one of the first and second reflectors (1a, 1b) has at least one notch (4) passing through said reflection plate (2) over its entire thickness (e2).

3. Device (2) according to claim 1 or 2, characterized in that the reflection plate (2) of at least one of the first and second reflectors (1a, 1b) is metallic.

4. Device (5) according to any one of claims 1 to 3, characterized in that at least one of the first and second reflectors (1a, 1b) comprises a main surface, inclined at an angle relative to the plane of the printed circuit board (6), with an angle inclination which is between 20° and 70°.

5. Device (5) according to any one of claims 1 to 4, characterized in that the first reflector (1a) and the second reflector (1b) surround the first radiofrequency antenna (9).

6. Device (5) according to any one of claims 1 to 5, characterized in that: - one of the first or second faces (7, 8) of the printed circuit board (6) is provided with a second radiofrequency antenna (11); and - the at least one reflector includes two sets of reflectors, where each set of reflector(s) is associated with a respective one of the first and second radiofrequency antennas (9, 11).

7. Device (5) according to claim 6, characterized in that a first set of reflector(s) comprises the first and second reflectors (1a, 1b), and a second set of reflector(s) comprises a third reflector (1c).

8. Device (5) according to any one of claims 1 to 7, characterized in that the printed circuit board (6) comprises a ground plane, each fixing lug (3) of each reflector being electrically connected to said ground plane.

9. Gesture detector (14) for controlling the automatic opening of a motor vehicle opening, comprising: - A device (5) according to any one of claims 1 to 8; and - At least one computer (15), configured to receive as input a signal from the at least one radiofrequency antenna (9), to carry out processing of this signal so as to detect a predetermined gesture carried out by a human operator, and to generate an opening instruction for said motor vehicle opening when a predetermined gesture is detected.

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