Wireless communication system between a motor vehicle and a user badge

Abstract

Wireless communication system (10) between a motor vehicle and a user badge such as a smartphone, comprising: - a primary antenna (110), for the transmission of an initial radio frequency signal (U1); and - a metal guide structure (120), having a first opening (121) located opposite the primary antenna (110), for injecting the initial radio frequency signal (U1) into a cavity (125) delimited by said guide structure, and at least one second opening (1221; 1222) arranged remotely from the primary antenna (110); wherein: - the guide structure (120) is configured to bring the initial radio frequency signal (U1) from the first opening (121) to each second opening (1221; 1222), each second opening (1221; 1222) forming a slot antenna transceiver; and - the guiding structure (120) is formed by at least part of a pillar (11) of a mechanical structure of the motor vehicle.Figure for the abbreviation: Figure 2.

Description

Title of the invention: Wireless communication system between a motor vehicle and a user badge technical field

[0001] The invention relates to the automotive field and more particularly to a wireless communication system intended to be embedded in a motor vehicle, to establish bidirectional communication with a user badge.

[0002] The invention relates more particularly, but not exclusively, to communication according to a Bluetooth standard, allowing the receipt of a user authentication code from the user badge. State of the art

[0003] It is known in the prior art to equip motor vehicles with one or more wireless communication systems, to enable two-way communication with a user badge.

[0004] The user badge refers to a wireless communication device capable of establishing two-way wireless communication with the vehicle's onboard wireless communication system for data exchange. This data includes, in particular, a user authentication code initially stored in the user badge. The user badge may consist of a dedicated device or a smartphone with dedicated software application.

[0005] Communication via said wireless communication system allows in particular user authentication at the vehicle level, to authorize access to functions or services such as unlocking a door, opening a door, starting the vehicle, or to access preferred settings inside the vehicle (seat adjustment, radio station, etc.).

[0006] In the prior art, the wireless communication system includes at least one radio frequency antenna, preferably of the monopole type, located for example near a door handle, in a lateral region of the vehicle.

[0007] The radio frequency antenna must therefore be integrated into an environment containing numerous metallic targets, whether the vehicle's bodywork or its internal mechanical structure. The radio frequency signals emitted and received by the radio frequency antenna are highly sensitive to this metallic environment, which can completely block the radio frequency radiation. Furthermore, even if the radio frequency radiation is not completely stopped by this metallic environment, the latter strongly influences the antenna's radiation pattern. It is therefore necessary to carry out thorough antenna sizing studies to anticipate The impact of the metallic environment on the antenna's radiation pattern must be considered, and this impact compensated for by using very specific antenna shapes. These antenna sizing studies are time-consuming and specific to each particular metallic environment associated with a specific vehicle model. Furthermore, the antenna sizing is then linked to a very precise antenna position on the vehicle, imposing significant constraints in terms of the accuracy of the antenna's mechanical integration.

[0008] Another solution is to position the wireless communication system between the metallic environment and the detection zone. For example, when the detection zone is located outside the vehicle, the wireless communication system extends into an external region of the vehicle, outside a mechanical structure of the vehicle, on the side of this structure opposite the passenger compartment. However, such an arrangement results in greater environmental constraints on the wireless communication system, and therefore a higher cost and, where applicable, fewer recycling possibilities.

[0009] An objective of the present invention is to provide a wireless communication system intended to be embedded in a motor vehicle, to establish bidirectional communication with a user badge, and which offers easy integration in a metallic environment.

[0010] An objective of the present invention is to propose a wireless communication system intended to be embedded in a motor vehicle, to establish bidirectional communication with a user badge, and which does not require high precision in terms of mechanical integration.

[0011] Another objective of the present invention is to propose a wireless communication system intended to be embedded in a motor vehicle, to establish bidirectional communication with a user badge, and which does not necessarily involve exposure to strong environmental constraints. Description of the invention

[0012] This objective is achieved with a wireless communication system between a motor vehicle and a user badge such as a smartphone, which includes: - a radio frequency transmitting and receiving antenna, called the primary antenna, configured to transmit an initial radio frequency signal whose carrier has a central wavelength X; and - a metal guide structure, equipped with a first opening located opposite the primary antenna, for injecting the initial radio frequency signal into a cavity delimited by said guide structure, and with at least a second opening formed in a face of the guide structure and arranged offset relative to the antenna primary ; in which: - the guidance structure is configured to bring the initial radio frequency signal from the first opening to each second opening, each second opening forming a slot antenna type transceiver for the emission of a secondary radio frequency signal from the initial radio frequency signal; and - the guidance structure is formed by at least part of a pillar of a mechanical structure of the motor vehicle.

[0013] A second opening is referred to as a transceiver because it is further configured, during operation, to receive a radio frequency response signal emitted by the user badge. This response signal travels through the guidance structure to the primary antenna, which is further configured to receive this signal from said response signal.

[0014] The idea behind the invention is thus to exploit the metallic environment of the wireless communication system to form at least one slot antenna-type radio frequency transceiver. Therefore, instead of being an obstacle to the easy integration of a radio frequency antenna, this metallic environment is, on the contrary, used to its advantage to form at least one slot antenna.

[0015] This enhancement of the metallic environment, and more specifically of a pillar belonging to a mechanical structure of the vehicle, involves modifying it to form the first and second openings. As detailed below, due to their small size, these openings do not compromise the original function of the pillar.

[0016] According to the invention, each second opening formed in the pillar constitutes a radio frequency transceiver, which, in operation, emits a so-called secondary radio frequency signal derived from the initial radio frequency signal. This radio frequency transceiver behaves like a radio frequency antenna, in particular a monopole radio frequency antenna. It is therefore referred to as a slot antenna, each second opening advantageously having a slot shape.

[0017] The radiation emitted by this radio frequency transceiver is not blocked by the metal of the pillar, since this radiation emerges directly from the pillar. Similarly, since the radiation emerges directly from the pillar, the radiation pattern of this radio frequency transceiver is also not significantly distorted by the metal of the pillar.

[0018] Thus, the influence of the metallic environment, and more particularly of the metal mechanical structure, is minimized.

[0019] It is therefore no longer necessary to carry out in-depth antenna sizing studies to compensate for the impact of the metallic environment on the diagram of radiation. In particular, an isotropic radiation pattern is easily obtained.

[0020] For the same reason, it is no longer necessary to impose a very precise positioning of the wireless communication system, relative to the specific metallic environment formed by the vehicle, and more particularly relative to the metallic mechanical structure of said vehicle.

[0021] It also becomes unnecessary to multiply the emission and reception points to cover a desired detection area, to compensate for the existence of shadow areas formed by metallic obstacles.

[0022] The radiation pattern of each transmitter-receiver depends primarily, if not exclusively, on the shape of the corresponding second aperture in the metal guide structure. It is therefore particularly easy to obtain a desired shape for this radiation pattern.

[0023] A wireless communication system is thus produced offering easy integration into a metallic environment, more particularly a metallic environment comprising a mechanical structure equipped with at least one structural metal pillar.

[0024] The invention also makes it possible to position the primary antenna on the inside of the vehicle, by positioning the first opening on the inside of the vehicle, while carrying out a radio frequency emission towards the outside of the vehicle, by positioning at least one second opening on the outside of the vehicle.

[0025] This provides a wireless communication system that offers easy integration into a metallic environment without requiring resistance to harsh environmental conditions. Because its resistance to environmental stresses is reduced, the wireless communication system according to the invention can have a lower manufacturing cost and offer greater recyclability.

[0026] The invention also makes it possible to transmit radio frequency signals both inside and outside the vehicle from a single primary antenna. This is achieved by opening secondary openings on two sides of the metal pillar, respectively on the inside and outside of the vehicle.

[0027] Similarly, the invention makes it possible to obtain several transmission and reception points using a single primary antenna. This is achieved by simply opening several secondary openings in the metal pillar.

[0028] Preferably, the central wavelength X corresponds to a frequency between 1 GHz and 10 GHz.

[0029] The primary antenna is advantageously configured to emit a signal according to the Bluetooth standard.

[0030] Advantageously, the primary antenna is configured for the transmission of the initial radio frequency signal, and for the reception of a response radio frequency signal emitted in use by the user badge.

[0031] Preferably, the primary antenna comprises a radiating element connected to an electronic power supply circuit, with the radiating element located inside the guiding structure and connected to the electronic power supply circuit through the first opening in the guiding structure.

[0032] Each second opening in the guiding structure advantageously has an elongated shape, with a greater length between >74 and 2*X.

[0033] Preferably, each second opening in the guide structure has an elongated shape, with a greatest length between 1 cm and 10 cm.

[0034] Advantageously, the guiding structure comprises two large elongated faces, arranged opposite each other, located in use respectively on the inside and outside sides of the vehicle, and receiving the first opening and at least one second opening.

[0035] The first opening can be formed in the large face located in use on the inside of the vehicle.

[0036] The system may include several second openings, at least one second opening being formed in the large face located in use on the inside of the vehicle, and at least one second opening being formed in the large face located in use on the outside of the vehicle.

[0037] Preferably, the guide structure consists of at least part of a pillar of the mechanical structure, located in use between the front and rear doors of the motor vehicle.

[0038] The invention also covers a system for authenticating a user badge by a motor vehicle, which includes a wireless communication system according to the invention, and an authentication device equipped with at least one processor and at least one memory and configured to drive data exchanges via said wireless communication system so as to receive and recognize an authentication code of the badge.

[0039] The invention also covers an assembly comprising not only the wireless communication system, but also the user badge.

[0040] The invention finally covers a motor vehicle comprising a wireless communication system according to the invention. Description of the figures

[0041] Other features and advantages of the invention will become apparent upon reading of the description that follows. This is purely illustrative and should be read in conjunction with the attached drawings on which:

[0042] [Fig. 1] Fig. 1 schematically illustrates a motor vehicle equipped with a wireless communication system according to the invention;

[0043] [Fig.2] Fig.2 schematically illustrates a communication system wireless according to the invention, as shown in cross-section;

[0044] [Fig.3] Fig.3 schematically illustrates a communication system wireless according to a front view.

[0045] Detailed description of at least one embodiment

[0046] We begin by describing schematically and with reference to [Fig.1], a motor vehicle 1 equipped with a wireless communication system 10 according to the invention.

[0047] As detailed below, the wireless communication system 10 is integrated into at least one part of a mechanical structure of the vehicle 1. The mechanical structure of the vehicle is a metallic structure forming the body of the vehicle, ensuring the mechanical rigidity of the latter, and on which ornamental structures such as the bodywork are mounted.

[0048] According to the invention, the wireless communication system 10 is integrated more particularly into a pillar 11 of said mechanical structure, here a side pillar located between a front side door and a rear side door, known to those skilled in the art as "pillar B". In unrepresented embodiments, the wireless communication system according to the invention is integrated into any other structural pillar of the vehicle, for example a pillar A (located between a front side door and the front windshield), a pillar C (located between a rear side door and a rear side area), etc.

[0049] Pillar 11 is part, in whole or in part, of the wireless communication system 10.

[0050] The wireless communication system 10 is intended to achieve bidirectional communication (symbolized by arrow 21) with a badge 20.

[0051] As described in the introduction, badge 20 is worn, in use, by a user of vehicle 1. The user with badge 20 may be inside vehicle 1, in the passenger compartment, or outside vehicle 1 as schematically represented in [Fig.1].

[0052] The badge 20 may consist of a dedicated device or a smartphone equipped with a dedicated software application. It includes its own wireless communication means with the wireless communication system 10, and a memory in which it stores a user authentication code.

[0053] In use, the badge 20 and the wireless communication system 10 establish together a two-way communication, allowing the wireless communication system 10 in vehicle 1 to receive the user authentication code.

[0054] When it is confirmed, using this authentication code, that the user is authorized to use the vehicle, dedicated systems in the vehicle 1 then authorize functions or services such as unlocking a door, opening a door, starting the vehicle, or give access to preferred settings, particularly inside the vehicle (seat adjustment, radio stations, etc.).

[0055] Advantageously, the wireless communication system 10 is connected to an authentication device 30 via a communication link 31. The authentication device 30 is schematically represented in [Fig. 1] and comprises at least one processor and at least one memory. The authentication device 30 is configured to manage data exchanges with the badge 20, via the wireless communication system 10, in order to receive and recognize an authentication code. In particular, the authentication device 30 is configured to request a query of the badge via the wireless communication system 10, and to receive, from the wireless communication system 10, an authentication code provided by the badge 20.At least one authorized authentication code is stored in the memory of the authentication device 30, which can compare the code provided by the badge 20 with at least one authorized code, so as to generate a successful authentication signal if the two codes match. The successful authentication signal is then sent to auxiliary systems and devices to activate the functions or services mentioned above. The wireless communication system 10 and the authentication device 30 together form a user badge authentication system 300.

[0056] In an advantageous embodiment, the user badge authentication system 300 also includes a badge location function. This location function may implement a measurement of the received radio frequency signal strength, representative of the distance between the badge 20 and at least one transceiver formed, as described below, in a metal guide structure belonging to the wireless communication system 10 (a technique known as RSSI, for Received Signal Strength Information). Advantageously, the location function uses a plurality of transceivers, belonging to the same wireless communication system 10 or to several distinct wireless communication systems 10. As a complement to, or alternative to, the RSSI technique, the location function may implement a triangulation calculation.

[0057] An example of the implementation of a wireless communication system 10 is then illustrated schematically with reference to Figures 2 and 3. In [Fig. 2], the The wireless communication system 10 is schematically represented in a cross-sectional view. In [Fig. 3], the wireless communication system 10 is schematically represented in a front view.

[0058] The wireless communication system 10 includes a primary antenna 110, comprising a radiating element 111 connected to a printed circuit board 112 on which is integrated an electronic power supply circuit (not specifically shown).

[0059] The radiating element 111 is preferably a simple monopole antenna.

[0060] The primary antenna 110 is configured to emit an initial radio frequency signal Ul, the carrier of which has a central wavelength X. The central wavelength X is associated with a frequency f=C / X, with C the speed of light in a vacuum.

[0061] The initial radio frequency signal Ul can be amplitude modulated, with a much lower modulation frequency. Alternatively, the initial radio frequency signal U1 has a variable carrier frequency, with a frequency spectrum extending over a frequency range centered on f=C / X.

[0062] Advantageously, the frequency f=C / X belongs to the UHF (Ultra High Frequency) range. For example, the frequency f=C / X is between 1 GHz and 10 GHz, more preferably between 2 GHz and 3 GHz, and even more preferably between 2.4 GHz and 2.5 GHz.

[0063] In a preferred embodiment, the initial radio frequency signal Ul conforms to the Bluetooth® standard, which is a telecommunications standard enabling bidirectional data exchange over short distances, using radio frequency waves in a frequency band ranging from 2.4 GHz to 2.483 GHz. More preferably, the initial radio frequency signal Ul conforms to the BLE standard, for Bluetooth Low Energy, this standard offering reduced energy consumption through frequency-hopping spread spectrum.

[0064] The primary antenna 110 is further configured to receive a radio frequency response signal, originating directly or indirectly from the badge 20 described in the introduction. The response signal has characteristics similar to those of the initial radio frequency signal Ul, particularly in terms of the center frequency of the carrier.

[0065] The wireless communication system 10 further comprises a guiding structure 120. The guiding structure 120 is a hollow metal structure that defines an internal volume, or cavity 125. The cavity 125 is elongated with an elongation axis A (straight or not). The guiding structure 120 is configured to guide the initial radio frequency signal Ul along its elongation axis A. The guiding structure 120 may have a variable internal cross-section along the axis A and / or a irregular shape. We can consider that the guiding structure 120 forms a waveguide, which may be imperfect.

[0066] According to the invention, the guide structure 120 is formed by at least part of the metal pillar 11 described with reference to [Fig. 1].

[0067] The guiding structure 120 is provided with a first opening 121, located in relation to the primary antenna 110 for the injection of the initial radio frequency signal U1 into the guiding structure 120.

[0068] The first opening 121 is a through opening, passing through one face of the guide structure 120 in the direction of the thickness, to connect the outside of the guide structure 120 with the cavity 125. The first opening 121 has reduced dimensions, with a diameter advantageously less than 5 cm, or even less than 2 cm.

[0069] In the example illustrated in [Fig.2], and advantageously, the primary antenna 110 is positioned with the radiating element 111 inserted inside the guiding structure 120 via said first opening 121, and the printed circuit board 112 located outside the guiding structure 120. In a variant not shown, the radiating element also extends outside the guiding structure 120, but radiates inside the latter.

[0070] Advantageously, and as illustrated in [Fig.2], the first opening 121 is formed in a lateral face of the guide structure 120. In unrepresented variants, the first opening 121 is located on an end face of the guide structure 120.

[0071] The guide structure 120 is further provided with at least one second opening. Here, but not limitingly, the guide structure 120 is provided with two second openings 122i and 1222.

[0072] Each second opening 122b 1222 is a through opening, passing through a face of the guide structure 120 in the thickness direction, to connect the outside of the guide structure 120 with the cavity 125.

[0073] The guidance structure 120 is configured to guide the initial radio frequency signal U1 into the cavity 125, from the first opening 121, and more particularly to bring this signal from the first opening 121 to each second opening 122b 1222.

[0074] According to the invention, the dimensions and positioning of a second aperture 122b 1222 on the guide structure 120 define a slot antenna. Each second aperture 122b 1222 is thus configured for the transmission of a secondary radio frequency signal U2b U22 derived from the initial radio frequency signal U1. Each second aperture 122b 1222 is further configured for the reception of a radio frequency signal emitted during use by the badge 20, this signal then being carried to the primary antenna via the guiding structure 120. Each second aperture 122b 1222 thus forms a radio frequency transceiver.

[0075] In a manner known per se, a slot antenna is formed by a through-hole in a metallic surface, the dimensions of the through-hole defining, in particular, the transmit-receive frequency of the antenna. A slot antenna behaves in practice like a monopole antenna.

[0076] Here, the slot antenna is indirectly powered via the initial radio frequency signal U1, which generates an induced current in the metal guiding structure 120. This induced current, in turn, generates a radio frequency emission at an aperture 122b or 1222, respectively, placed in the path of the induced current lines.

[0077] Each second aperture 122b 1222 is arranged at a distance from the primary antenna 110. For example, there is an offset of at least twice the wavelength X of the initial radio frequency signal Ul, for example, between three and five times this wavelength X. In practice, there is advantageously a distance greater than or equal to 10 cm, and even greater than or equal to 20 cm, between the primary antenna 110 and the nearest edge of a second aperture 122b respectively 1222. This offset ensures that guidance of the initial radio frequency signal Ul has indeed been initiated in the waveguide structure 120, between the first aperture 121 and the second aperture 122b respectively 1222. The confirmed existence of such guidance makes it possible to get as close as possible to ideal conditions for the realization of a slot antenna in a waveguide, which facilitates the design.However, it is possible to compensate for less than ideal conditions by playing with the shape and / or location of a second opening 122b respectively 1222. .

[0078] The shape of each second opening 122b 1222 is an elongated shape, with dimension L along the elongation direction. It may be a rectangle with long side L, or a rectangle with rounded edges, or a trapezoidal shape, or a rectangle extended by two rounded regions, etc. Preferably, each second opening 122b 1222 has its longest dimension L oriented parallel to the elongation axis A of the guide structure 120. Advantageously, the dimension L is between 1 cm and 10 cm.

[0079] The dimensions of the slot antenna, and more particularly its largest dimension L, define its transmit-receive frequency. Advantageously, this largest dimension L is between X / 4 and 2*X, with advantageously L being substantially equal to X / 2, to within ±20%, or even ±10%, or even ±5%.

[0080] Each second opening 122b 1222 has a width 1, defined along an axis orthogonal to the axis of said largest dimension L, and whose dimensions are well in less than L. For example, we have a ratio greater than or equal to 10 between the largest dimension L and said width 1. Where appropriate, we define the width 1 as being the largest dimension of the second opening 122b 1222 along an axis orthogonal to the axis of said largest dimension L.

[0081] For a frequency of 2.4 GHz, the condition L = X / 2 corresponds to L = 6.25 cm. Due to its small dimensions, such an opening is therefore easily made in the pillar 11. The mechanical performance of the pillar 11 is not affected, especially since the longer side L is oriented parallel to the elongation axis A of the pillar 11. The initial function of the pillar 11 is therefore not affected by the addition of its additional radio frequency transmission and reception function.

[0082] Here, the slot antenna is formed within a metal guiding structure 120. The initial radio frequency signal U1 propagates within the guiding structure 120. It generates, in the metal envelope defining the guiding structure 120, an induced current that follows streamlines with nodes and antinodes. For optimal efficiency of the slot antenna, the through-hole 122i, or 1222 respectively, is advantageously positioned at an antinode.

[0083] Advantageously, and as shown in Figures 2 and 3, the guide structure 120 comprises two large faces 123, 124, arranged opposite each other, which extend along the elongation axis A, and are located, in use, respectively on the inner and outer sides of the vehicle. For example, but not limited to, the guide structure 120 has a square or rectangular cross-section in a plane orthogonal to the axis A.

[0084] Advantageously, the first opening 121 is located on one of the first large faces 123 of the guiding structure 120, which, in use, is situated on the inside of the vehicle. Thus, the primary antenna 110 is also, in use, located on the inside of the vehicle, protected from weathering and other environmental constraints.

[0085] Advantageously, each second opening 122b respectively 1222, is located on one or the other of the large faces 123 and 124 of the guiding structure 120.

[0086] Advantageously, and as shown in Figures 2 and 3, at least one second opening 1222 is located on the large face 124 of the guidance structure 120, situated on the exterior side of the vehicle. This enables transmission and reception on the exterior side of the vehicle, allowing communication with a badge 20 located outside the vehicle. The radio frequency communication is then advantageously used to control access to the vehicle.

[0087] In addition or alternatively, and as shown in Figures 2 and 3, at least one second opening 122i is located on the large face 123 of the guide structure 120, situated in use on the inside side of the vehicle. Thus, a Transmission and reception are performed on the vehicle's interior side, to communicate with a 20-digit badge located inside the vehicle. Radio frequency communication is then advantageously used to control a personalized setting of driving options.

[0088] Advantageously, and as shown in Figures 2 and 3, the guiding structure 120 comprises at least one second aperture 122i on the large face 123 located in use on the inside of the vehicle, and at least one second aperture 1222 on the large face 124 located in use on the outside of the vehicle. Thus, a single primary antenna 110 performs transmission and reception on both the inside and outside of the vehicle.

[0089] In variants not shown, the guidance structure has several second openings on its large face 124 and / or on its large face 123, to provide several transmission and reception points on the outside and / or inside of the vehicle, using a single primary antenna 110.

[0090] The invention is not limited to the detailed examples above, and also covers numerous variations with a different number of second apertures in the guiding structure, with other shapes, dimensions and / or orientations of the first and second apertures in the metal guiding structure, with other center frequencies of the initial radio frequency signal, with other portions of the metal mechanical structure used as a guiding structure, etc. In other variations, not shown, the guiding structure is provided with at least one array of through-holes, together forming an antenna array offering a direct overall radiation pattern.

[0091] In another variant, not shown, the printed circuit board 112 receiving the primary antenna 110 also receives an auxiliary antenna (not shown), which transmits in the opposite direction to the guidance structure 120. Advantageously, the primary antenna then allows transmission to the outside of the vehicle, via the guidance structure 120, while the auxiliary antenna allows transmission directly into the vehicle, without passing through the guidance structure 120. This variant makes it easy to determine whether the user badge is inside or outside the vehicle, depending on whether the return signal comes back to the primary antenna or to said auxiliary antenna.

Claims

Claims

1. System (10) for wireless communication between a motor vehicle (1) and a user badge (20) such as a smartphone, characterized in that it comprises: - a radiofrequency transmission and reception antenna called primary antenna (110), configured for the transmission of an initial radiofrequency signal (Ul) whose carrier has a central wavelength / .; and - a metal guide structure (120), provided with a first opening (121) located opposite the primary antenna (110), for injecting the initial radiofrequency signal (U1) into a cavity delimited by said guide structure (120), and at least one second opening (122i; 1222) formed in a face of the guide structure (120) and arranged offset relative to the primary antenna (110); in which: - the guide structure (120) is configured to bring the initial radiofrequency signal (U1) from the first opening (121) to each second opening (122i; 1222), each second opening (122i; 1222) forming a slot antenna type transceiver for transmitting a secondary radiofrequency signal (U2i; U22) originating from the initial radiofrequency signal (U1); and - the guide structure (120) is formed by at least part of a pillar (11) of a mechanical structure of the motor vehicle.

2. System (10) according to claim 1, characterized in that the central wavelength X corresponds to a frequency between 1 GHz and 10 GHz.

3. System (10) according to claim 2, characterized in that the primary antenna (110) is configured to transmit a signal (Ul) according to the Bluetooth standard.

4. System (10) according to any one of claims 1 to 3, characterized in that the primary antenna (110) is configured for the transmission of the initial radiofrequency signal (110), and for the reception of a response radiofrequency signal transmitted in use by the user badge (20).

5. System (10) according to any one of claims 1 to 4, characterized in that the primary antenna (110) comprises a radiating element (111) connected to an electronic power supply circuit current, with the radiating element (111) located inside the guide structure (120) and connected to the electronic current supply circuit through the first opening (121) in the guide structure

6. System (10) according to any one of claims 1 to 5, characterized in that each second opening (122i; 1222) in the guide structure (120) has an elongated shape, of greatest length (L) between X / 4 and 2*X.

7. System (10) according to claim 6, characterized in that each second opening (122i; 1222) in the guide structure (120) has an elongated shape, of greatest length (L) between 1 cm and 10 cm.

8. System (10) according to any one of claims 1 to 7, characterized in that the guide structure (120) comprises two large elongated faces (123, 124), arranged face to face, located in use respectively on the inside and outside of the vehicle, and receiving the first opening (121) and the at least one second opening (122i; 1222).

9. System (10) according to claim 8, characterized in that the first opening (121) is formed in the large face (123) located in use on the interior side of the vehicle.

10. System (10) according to claim 9, characterized in that it comprises several second openings (122i; 1222), at least one second opening (1220) being formed in the large face (123) located in use on the inside of the vehicle, and at least one second opening (1222) being formed in the large face (124) located in use on the outside of the vehicle.

11. System (10) according to any one of claims 1 to 10, characterized in that the guide structure (120) is constituted by at least part of a pillar (11) of the mechanical structure, located in use between front and rear doors of the motor vehicle (1).

12. System (300) for authenticating a user badge by a motor vehicle, which comprises a wireless communication system (10) according to any one of claims 1 to 11, and an authentication device (30) provided with at least one processor and at least one memory and configured to control data exchanges via said wireless communication system so as to receive and recognize an authentication code of the badge (20).

13. A motor vehicle (1) comprising a wireless communication system (10) according to any one of claims 1 to 11.

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