CH718437A2 - Method and system for controlling visitors in an access zone inside an amusement park. - Google Patents

Abstract

The invention relates to a method for controlling visitors (V) in an access area (7) inside a leisure park, for example a ski area or an amusement park, comprising: Transmitting signals Bluetooth towards the access area with several beacons (30) mounted on a common gantry (3), the relative position of the beacons being known; Filming with the aid of a first camera (31) said access zone, so as to generate a fixed or animated image of the access zone seen from above; Single out at least one visitor in said image; Receive in a server (5) the position of a mobile device, for example a smartphone or a smartwatch, determined by this mobile device using said Bluetooth signals; Check whether a location received from mobile equipment matches the location of said singulated visitor; Check the right of access of said singled out visitor. The invention also relates to a visitor control system (V) in an access area (7) inside a leisure park.

Description

Technical area

The present invention relates to the problem of controlling visitors in amusement parks, in particular ski resorts or amusement parks.

State of the art

[0002] Many ski resorts and amusement parks use RFID elements, for example transponders integrated into a smart card or a watch, for access control and access payment. Users wishing to ski must purchase an RFID item and load it with a monetary amount to gain access to the facilities. Payment is most often made in advance, by preloading the card with a prepaid amount which is debited according to time (for example by the hour or by the day), or by controlling each access to the facilities by means of an RFID reader near each access gate.

[0003] These systems operate reliably and economically. Conventional RFID readers however have a very limited range, typically of the order of a few centimeters or a few meters. They therefore only make it possible to detect users in the immediate vicinity of the access control terminals, but not to locate them when they are far from the installations. They also require complex logistics for the distribution and revocation of RFID elements.

[0004] EP3477602A1 describes a method and a device for controlling access and payment in a leisure park, implementing a dedicated device. This solution allows precise location of users throughout the fleet, but makes the management of user identification devices even more complex and costly.

[0005] US2017/270734 describes a queue control system for amusement parks which comprises at least one portable device and a control system. The portable device is provided with an identifier allowing not only access to a given attraction by NFC communication of this identifier to an NFC station, but also detection of its position in a virtual queue to access one of the attractions of the park. This position is then communicated to the various units of the system by means of medium and/or long range communication.

[0006] GB2469026 describes a system that can be used for example in an airport to track the position of a passenger using near field communications (RFID tag), telecommunications (DECT), femtocell, Wi-Fi- fi etc, providing specific information about the passenger's movements and guiding the passenger from check-in to plane departure or from plane to arrival. The system can also be used in a hospital, a multi-activity exhibition, conferences or concerts, and provide information to a waiting person.

[0007] US2015/091726 relates to a system for providing location-based services, in particular in an amusement park.

[0008] US2014257889 describes a system for locating mobile devices making it possible to optimize waiting times at queues according to customer flows. It implements wireless detection devices for mobile devices, for example telephones equipped with a Bluetooth or Wi-Fi interface.

[0009] There are also known systems for payment and access control to the facilities of a leisure park which use visitors' smartphones both for payment and for controlling access to visitors. These devices frequently use a very short distance wireless interface, for example an NFC (Near Field Communication) interface. The visitor must therefore take their smartphone out of their pocket and press it against an NFC reader near the access control gate in order to allow this gate to open. It is therefore necessary to take the gantry out of its pocket, or even to handle it, which may prove to be impractical in a ski resort or with gloves for example.

Brief summary of the invention

[0010] An object of the present invention is to provide a method for controlling visitors in an access zone which is free from the limitations of the above methods.

Another object of the invention is a method for controlling visitors in an access zone which uses the visitors' personal devices, for example mobile equipment, but does not require manipulation in the access zone.

[0012] According to the invention, these objects are achieved in particular by means of a method of controlling visitors in an access zone inside a leisure park, for example a ski area or a park. attraction, comprising: Transmitting Bluetooth signals towards the access area with several beacons mounted on a common gantry, the relative position of the beacons being known; Filming said access area using a first camera looking down, so as to generate a still or animated image of the access area seen from above; Single out at least one visitor in said image; Receive the position of a mobile device, for example a smartphone or a smartwatch, determined using said Bluetooth signals; Checking whether a position received from a mobile device corresponds to the position of said singled out visitor; Check the right of access of said singled out visitor.

[0013] The method thus makes it possible to verify the access rights of one or more visitors visible on the image of an access zone. It is then possible to use this information, for example, to detect visitors without access rights, and/or to authorize access to visitors holding such access rights.

[0014] This method does not require visitors to use dedicated equipment, but only mobile equipment such as a smartphone or a smartwatch, the majority of which are equipped anyway.

[0015] A specific software application (“app”) can be loaded into the mobile equipment in order to determine its position on the basis of the Bluetooth signals received from the various beacons.

[0016] The method may comprise a step of determining at least one unauthorized visitor whose position determined with said image does not correspond to a position received, or at least one unauthorized visitor who does not have access rights. access to the controlled access area.

[0017] A visitor is considered unauthorized if he is in the access zone but, for example: he has no mobile equipment, or his mobile equipment is stopped; he has not installed or started the dedicated software application; he has not started the required Bluetooth services in his mobile device; he cannot prove that he has valid access rights to the controlled area.

[0018] It is thus possible to automatically determine the presence of such an unauthorized visitor in the access zone, and to act appropriately.

[0019] The reaction to the presence of an unauthorized visitor may include capturing an image of this unauthorized visitor using an additional camera. This image can be displayed on the terminal of a supervisor who can for example intercept the unauthorized visitor, and deny him access to the controlled area, or sell him access.

[0020] The method may include tagging an image portion including said unauthorized visitor. This allows the supervisor to easily determine which visitor, among a group of visitors or in a queue, is unauthorized.

[0021] The position of mobile equipment can be determined by each mobile equipment and sent to a server. This makes it possible to distribute the computing power and simultaneously locate a large number of users present simultaneously near the portal

[0022] Each mobile device can determine its position using the Bluetooth AOD (Angle of Departure) method using Bluetooth signals emitted by said beacons.

[0023] The beacons may consist of antennas transmitting a Bluetooth Low Energy signal.

[0024] The beacons can be divided into several groups or anchors on said gantry. The beacons are closer to at least one antenna of the same group than to the most pocket antenna of another group.

[0025] Each group of beacons may comprise several beacons arranged in a matrix. Each matrix can have at least N=1 row and M>1 column. The different beacons of a group can be mounted on the same conductive plate, for example a PCB board.

[0026] All beacons within each group can be linked to a common Bluetooth transmitter.

[0027] All beacons can be connected to a common Bluetooth transmitter.

[0028] The beacons within each group can transmit in turn.

The beacons can transmit successively in several different Bluetooth channels. This minimizes the influence of noise caused, for example, by reflections from Bluetooth signals.

The beacons are preferably mounted on the same substrate, for example the same printed circuit board. This makes it possible to guarantee precise relative positioning of the beacons, in the factory.

The substrate can then be mounted on the gantry.

[0032] The gate can be placed above the access area, so that visitors must pass under the gate to access the controlled area.

The Bluetooth signals emitted by said beacons are preferably generated by the same transmitter.

The first camera is preferably a distance measurement camera. This makes it easier to single out the different visitors on an image, by differentiating between the different shots. This also makes it possible to determine the position of each visitor in two dimensions and to have information on its size.

The first camera is advantageously mounted on the gantry. This ensures precise and stable relative positioning between the beacons and the first camera. This positioning facilitates the correspondence between the positions of the visitors singled out on the image and the positions determined by the mobile equipment.

The invention also relates to a visitor control system in an access zone inside a leisure park, for example a ski area or an amusement park, comprising: A gate; Beacons mounted on the gantry; A transmitter connected to said beacons so that these beacons emit Bluetooth signals towards the access area; A first camera looking down to film the access area, so as to generate a fixed or animated image of the access area seen from above; A software module for singling out at least one visitor in said image; A software module for receiving the position of a mobile device, for example a smartphone or a smartwatch, determined by this mobile device; A software module for checking whether a position received from a mobile device corresponds to the position of a singled out visitor; A software module to verify the right of access of said singled out visitor.

[0037] The system may include an additional camera to capture a frontal image of unauthorized visitors in the access area.

Brief description of figures

Examples of implementation of the invention are indicated in the description illustrated by the appended figures in which: FIG. 1 illustrates a schematic view of an example of a system for implementing the invention. • Figure 2 shows an image of an access area viewed from above. • Figure 3 shows an image of an access area viewed from the front. • Figure 4 illustrates an example of a flowchart of a method according to the invention.

Example(s) of embodiment of the invention

An example of a system according to the present invention is illustrated schematically in Figure 1. It is intended to control the access rights of visitors Vi in a leisure park, for example a ski area or an amusement park. The system can be used to control the main access to the leisure park, for example in order to let in only visitors who have acquired a valid entry ticket, or to control access to attractions or ski lifts once the visitors are inside this leisure park, for example in order to invoice these accesses, to count the number of visitors, to manage the flow of visitors, etc.

In this example, the system is deployed on a ski area as an example of a leisure park in order to control the access of visitors, for example skiers, to a ski lift of this station. Other amusement parks including amusement parks, vacation clubs, outdoor festivals, etc. may implement the system.

The leisure park has several facilities, here ski lifts. Visitor access Vià each installation is controlled by a gate 3 above the access zone 7, and/or a terminal next to this access zone. Access control may involve controlling the opening of a gate, for example a turnstile or a door, giving access to the installation. In a preferred embodiment, at least some installations can be accessed without going through a gate. Access control then aims to control which visitor has accessed which facility at which time, and/or to transmit an indication when a visitor without access rights is near the controlled access zone. In this case, the access control terminal can for example be used to detect and identify unauthorized visitors who are, for example, in a queue.

[0042]Visitors must be equipped with mobile equipment 2, for example a smartphone, a smartwatch, etc., in order to prove their right of access. Additional access control means, for example an RFID card reader, can be provided to control visitors without such mobile equipment or when the battery of their equipment is discharged. A software application (“app”) dedicated to access control must be installed in the mobile equipment 2, and executed at the time of access control.

The gantry 3 is provided with several beacons 30 which emit Bluetooth signals. Optionally, at least some of the beacons can be mounted on a terminal at the height of the participants. The position of the various beacons is known. In one embodiment, the beacons are spaced apart by a distance less than or equal to λ/2, for example a distance equal to λ/3, λ being the wavelength of the Bluetooth signal (approximately 12.5 cm to 2.4GHz). This arrangement allows a high resolution of the precision measurement with a given number of beacons. The desired high resolution is also obtained thanks to a judicious arrangement of the beacons, for example an arrangement in a line, in a matrix or in a circle, and thanks to a sufficient number of beacons.

The beacons 30 are advantageously mounted on a single printed circuit board, fixed to the gantry, which makes it possible to guarantee the precise positioning of the beacons in the factory. It is also possible to provide several printed circuit boards with several tags 30 on each board. Each printed circuit board, called an anchor, carries a group of 30 tags.

The signal emitted by the different beacons 30 is generated by a single common electronic transmitter, for example a Bluetooth Low Energy 5.1 or higher version radio. The use of a single transmitter makes it possible to guarantee a phase shift which depends only on the position of the various beacons. The transmitter can be connected to the different beacons by alternately open analog switches, so that the different beacons transmit in turn. To achieve positioning at time „t“, a single Bluetooth message can be used, which can be divided into different parts (as many as there are beacons) which are each sent by a beacon.

The position of each mobile device 2 can be determined by this mobile device and sent to the server 5. This makes it possible to distribute the computing power necessary for this location, and thus to simultaneously locate a large number of users present simultaneously near of the porch.

For this purpose, the starting angle of the Bluetooth signals emitted by the various beacons 30 is advantageously determined by each mobile device 2 which receives them, and used by this mobile device to determine its position by triangulation.

It is also possible to use the angle of arrival of the signals received by the mobile equipment to determine their position. It is also possible to calculate the position of the mobile equipment 2 in the server, or in the cloud.

The beacons can be divided into several groups (called anchors) on the same gantry 3. Each beacon is closer to at least one antenna of the same group than to the nearest antenna of another group. The distance between two neighboring beacons of the same group is preferably less than 20 centimeters, for example less than 10 centimeters. The distance between two groups is preferably greater than 30 centimeters. The different groups can be spaced from each other in a direction perpendicular to the crossing direction of the gantry.

Each group can comprise a matrix of tags, each matrix comprising at least N=1 row and M>1 column.

All tags 30 within each group can be mounted on the same plate, for example the same PCB.

[0052] All beacons 30 within each group can be connected to a common Bluetooth transmitter. The beacons can be connected via a demultiplexer which sends the Bluetooth signal in turn to the different beacons in the group. Within each group, the beacons therefore transmit in turn, cyclically.

[0053] All the beacons of the different groups can be connected to a common Bluetooth transmitter, via a demultiplexer.

The beacons can transmit successively in several different Bluetooth channels. This minimizes the influence of noise caused, for example, by reflections from Bluetooth signals.

It is for example possible to switch from one Bluetooth channel to another Bluetooth channel each time the Bluetooth signal is switched from one beacon 30 to another.

It is possible to provide for a beacon to transmit successively on several different channels, in order to minimize the influence of noise.

At least one camera 31 films the access area. The relative position of the camera 31 is fixed with respect to the beacons 30. The camera 31 can be mounted on the gantry 3 and fix the access zone 7 from above. Camera 31 may be mounted on the same printed circuit board as beacons 30, or mounted in a fixed position relative to the printed circuit board.

The camera 31 can be an RGB camera for filming in the visible range. It can also be an infrared camera in order to film an image less dependent on shadows or reflections. In an advantageous embodiment, the camera 31 is a distance measurement camera (depth-of-field) which measures the distance to the objects and to the people filmed in the access zone 7. It is also possible to use several cameras, for example two stereoscopic cameras, to film the access zone 7 from different directions.

A terminal provided with one or more front cameras 4 can be provided in order to film visitors Vi on the access zone in front view (from the front).

The camera 31 and the optional camera 4 send images or image sequences to a server 5. The server can be mounted on the gantry 3, or be installed remotely and accessed via a network, for example the Internet, a cellular network, Wi-Fi, etc. The server 5 can also be in the cloud, or include several machines connected to each other.

A software module executed on the server 5 makes it possible to analyze the sequence of images from above taken by the camera 31. An example of such an image is illustrated in FIG. 2; we see several visitors V1, Vi, Vn, here skiers, as well as equipment of the access zone 7, for example barriers 70 to channel visitors. The software module performs image pre-processing in order to crop it, correct contrast, brightness, sharpness, etc. in a second step, the software module makes it possible to single out the different visitors, that is to say to determine which portions of the 2D or 2.5D image correspond to a visitor. The singularization can be based on an image analysis. An artificial intelligence system makes it possible to classify the portions of the foreground (which can be determined using distance measurement and/or by contrast detection, for example if the ground is white) and to determine which belong to a visitor. The image analysis advantageously makes it possible to distinguish between two visitors side by side, the shape of the whole not corresponding to that of an individual visitor. The distinction between visitors can also be based on the measurement of distance, for example by determining the maximum local heights, corresponding to the tops of the skull or the helmet of each visitor. In the case where the access zone is filmed by several cameras 31, for example stereoscopic cameras, the analysis can also include a 3D reconstruction of the scene on the access zone in order to single out the different visitors even better.

[0062] The software module preferably carries out a follow-up (“tracking”) of the singularized visitors on several successive images, in order to reduce the computing power necessary for each image and to improve the reliability of the singularization. This monitoring makes it possible to obtain the trajectory of the center of gravity and the volume of each visitor.

The software module also determines the center of gravity CG1, in 2D or 3D, of each visitor V1.

The visitors' mobile equipment 2 receives via their Bluetooth interface the phase-shifted signals emitted by the various beacons 30 and determines their relative position in several successive instants. This position is then transmitted to the server 5 in a message, for example a sequence of messages or a data stream.

In an alternative embodiment, the visitors' mobile equipment 2 receives via their Bluetooth interface the phase-shifted signals emitted by the various beacons 30, measures their phase shift and transmits these phase shifts to the server 5 which determines the relative position of the moving equipment 2.

The software module receives this or these messages, and checks whether a message is received from a mobile device 2 indicating a position which corresponds to the position CG of one of the singled out visitors.

[0067] In the event of a match, the server 5 then checks whether the visitor Vi has a valid access right. To do this, he can ask the visitor for a message, preferably signed electronically, indicating his access rights. This message can also be included in the message indicating the position of the visitor. The access verification can also involve a “challenge-response” mechanism during which the server 5 poses a question (the challenge) to the mobile equipment 2 of the singled out visitor, to which this mobile equipment can only respond correctly. if he has access rights.

If no mobile equipment transmits a position corresponding to a single visitor, or if a mobile equipment 2 corresponding to the position of a visitor cannot prove that it has access rights, this visitor present on the picture 8 is not allowed. It can be marked as such on image 8 if this image is displayed on the terminal of a human monitor. It is also possible to use this information to block the opening of an access control gate. If such a gate is provided.

In a preferred embodiment, the front camera hangs a static or animated image 9 of the access area 7 as seen in Figure 3, and marks on this image with a marking 301 the unauthorized visitor Vi . The marking may for example comprise the framing of the image area comprising the unauthorized visitor, the highlighting of this area, etc. The image 9 thus marked is displayed on the terminal 6 of a human supervisor who can thus intercept the unauthorized visitor and ask him for another ticket for example. It is also possible to display, and optionally to mark, on the supervisor's terminal the image 8 taken by the first camera 31.

An example of a method according to the invention will be described in more detail in relation to FIG. 4. The first column of this figure is a flow diagram of the operations executed by the beacons 30. The second column is a diagram flow of operations executed by the overhead camera 31 and the associated transmission electronics. The third column is a flowchart of the operations executed by each mobile device 2 whose application is activated. The fourth column is a flow diagram of the operations performed by server 5.

[0071] During step 100, the beacons 30 on the gate 3 emit Bluetooth signals in the direction of the access zone 7. The beacons 30 have no other actions to perform and therefore have no no need to be connected to the server 5; however, they can be activated or deactivated.

[0072] During step 105, the camera 31 captures a still or moving image 8 of the access zone 7 seen from above. This image is then sent to the server 5 during step 106, for example through a cellular, Wi-Fi or other interface. The sequence is repeated so as to generate a video stream or a sequence of still images.

In another embodiment, a computer is directly connected to the cameras 31 and 4. This computer controls the cameras, carries out the image processing, and sends to the server 5 the access requests and the visitor information. .

[0074] During step 110, the mobile equipment 2 of each visitor in the access area having activated Bluetooth receives the Bluetooth signals emitted by the beacons 30.

[0075] During step 112, a software application executed by at least some of these mobile devices 2 determines the position of this mobile device from the phase differences between the signals received from the different beacons, which allows it to determine the starting angle of these signals and hence the relative position of the mobile equipment 2 with respect to the beacons 30. This relative position is sent to the server 5 during step 114, for example in the form of a message , writing to server 5, etc.

[0076] During step 116, the application of at least some mobile equipment communicates its access rights to the controlled area to the server 5. This step can be performed spontaneously, or on demand; for example, the mobile application can send a response to a challenge received from the server 5 in order to prove its access rights.

The communications from the mobile equipment 2 to the server 5 are preferably electronically signed so as to allow the server 5 to ensure that the positions and access rights received do indeed come from the mobile equipment 2 provided, and preventing another mobile device from impersonating.

During step 120, the software module in the server 5 receives an image 8 or a video stream from the camera 31. During step 122, this software module performs a preprocessing of the image 8 received, then singles out the various visitors Virrepresented in the image. This singularization can be performed by image processing and/or based on the depth information given by the distance measurement sensor of the camera 31.

[0079] During step 124, the software module determines the individual position of each visitor singled out on the image 8, for example the position of their center of mass CG1. The position can be determined in 2D or preferably in 3D thanks to the distance measurement camera 31.

[0080] During step 126, the server 5 receives the position of each piece of equipment that communicated it to it. This reception can occur at any time and repeatedly.

[0081] During step 128, the software module of the server 5 verifies the access rights of each device that communicated them. This verification can be carried out following the reception of a message from this mobile equipment, or at the request of the server. In one embodiment, the verification comprises an identification or an authentication of the mobile equipment 2, with an identification or authentication protocol, then the verification of the access rights of the identified or authenticated visitor in a database accessed by the server.

[0082] During step 130, the server software module 5 checks for each visitor singled out during step 122 whether the position of this visitor in the access zone 7, determined from the images of the camera 31 during step 124, corresponds to the position of a mobile device 2 received during step 126.

A correspondence is established for example if the distance between the center of gravity CG, of the visitor V1, determined from the image 8, and the position of a mobile device received during step 124 n' does not exceed a threshold value, for example 50 cm. Distance can be measured in 3D; it is indeed unlikely that a visitor carries his mobile equipment close to the ground, or above his head for example. Alternatively, a correspondence can be established if the position transmitted by the mobile equipment 2 corresponds to a 2D or 3D portion of the singularized visitor.

If no mobile device 2 indicates a position corresponding to a singled out visitor Vi, the method continues at step 134. Otherwise, when the singled out visitor Vi has a mobile device provided with the application which emits a position corresponding to that of the visitor on image 8, the method continues at step 132 during which a decision is made according to the access rights of this visitor.

If the access rights are valid and the visitor is authorized to access the controlled area, the method returns to step 120. In a variant, the visitor is counted. It is also possible to debit a monetary account linked to this visitor to charge him for access. The method may also include the opening of an optional gate to allow passage of the authorized visitor.

[0086] Otherwise, that is to say if the visingularized visitor does not have access rights to the controlled area, the method continues at step 134. During this step, a photo still or animated by the visitor is taken by the front camera. The unauthorized visitor can be marked on this image by means of a marking 301. The image thus captured is transmitted to the terminal of a nearby human supervisor, in order for example to block the passage of this unauthorized visitor, to sell a ticket, or ask him to prove his right of access in some other way.

[0087] Instead of, or in addition to step 134, other reactions can be taken during step 136 in order to react to the presence of an unauthorized visitor in the access zone 7. For example, it is possible to block an optional gate, to emit an audible and/or visual alarm (for example the display of a message on a screen visible from the reception area), or to send a message on the mobile equipment of this visitor in order to allow him to buy an access right, or to ask him to leave the access zone 7.

Reference numbers used in the figures

[0088] V Visitor 2 Mobile equipment 3 Gate 30 Beacons 31 Camera linked to the gate. 4 Front camera 5 Server 6 Access controller terminal 7 Access area 70 Barriers 8 Top image of the access area, captured with camera 31 linked to the gate 9 Front image of the access area, captured with the front camera 4 100 Emission of Bluetooth signals by the beacons 30 105 Capture an overhead image 8 of the access area 7 106 Send the overhead image 8 of the access area to the server 5 110 Receive signals from the beacons 30 112 Determine the position of the mobile equipment 114 Send a message with the position of the mobile equipment and its access rights 120 Receive in the server 5 the top image of the access zone 7 122 Processing of image and singling out of visitors View the top image. 124 Determine the position of singled out visitors from the top image 8 126 Receive messages from Vi visitors with the position of their mobile equipment 128 Check the access rights of Vi130 visitors For each singled out visitor, check whether a message received indicates a position of the mobile equipment corresponding to the position of the visitor determined from the image 8 132 For each singled out visitor, check the access rights of the mobile equipment 2 to the corresponding position 134 Capture or save a frontal photo 9 of a singled out but unauthorized visitor 136 Other reaction to the presence of a singled out but unauthorized visitor 201 Marking of a visitor on the image 200 301 Marking of a visitor on the image 300

Claims (15)

1. Method for controlling visitors (V) in an access zone (7) inside a leisure park, for example a ski area or an amusement park, comprising: Transmit (100) Bluetooth signals towards the access area with several beacons (30) mounted on a common gantry (3), the relative position of the beacons being known; Filming (105) said access area using a first camera (31) looking down, so as to generate a fixed or animated image (8) of the access area seen from above; Singularize (122) at least one visitor in said image; Obtaining (126) in a server (5) the position of a mobile device, for example a smartphone or a smartwatch, determined using said Bluetooth signals; Checking (130) if a position received from a mobile device corresponds to the position of said singled out visitor; Check (132) the right of access of said singled out visitor. 2. Method according to claim 1, the position of said mobile equipment being determined by said mobile equipment and received by said server. 3. The method of one of claims 1 or 2, comprising a step of determining at least one unauthorized visitor whose position determined with said image (8) does not correspond to a position received, or of at least an unauthorized visitor who does not have access rights to the controlled access area. 4. The method of claim 3, comprising capturing (134) an image (9) of said unauthorized visitor using an additional camera (4). 5. The method of one of claims 1 to 4, comprising the marking (301) of an image portion (9) comprising said unauthorized visitor. 6. The method of one of claims 2 to 5, wherein said mobile equipment (2) determines its position using the Bluetooth AOD (Angle of Departure) method. 7. The method of claim 6, wherein Bluetooth signals are transmitted by said several beacons (30) distributed in several groups on said portal, the antennas of each group being arranged in a matrix. 8. The method of one of claims 6 or 7, wherein a Bluetooth transmitter sends a signal successively to several beacons via a demultiplexer. 9. The method of one of claims 6 to 8, wherein a Bluetooth signal is emitted from said beacons (30) successively in several different channels. 10. The method of one of claims 6 to 9, wherein a Bluetooth signal is emitted successively from several beacons (30) successively in several different channels. 11. The method of one of claims 7 to 10, said beacons (30) of each group being mounted on the same substrate, for example the same printed circuit board, on said gantry. 12. The method of one of claims 1 to 11, said first camera (31) being a distance measurement camera. 13. The method of one of claims 1 to 12, said first camera (31) being mounted on said gantry (3). 14. Visitor control system (V) in an access zone (7) inside a leisure park, for example a ski area or an amusement park, comprising: A gate (3) Beacons (30) mounted on the gantry (3); A transmitter connected to said beacons so that these beacons emit Bluetooth signals towards the access area (7); A first camera (31) looking down to film the access area (7), so as to generate a fixed or animated image (8) of the access area seen from above; A software module for singling out at least one visitor in said image (8); A software module for receiving the position of a mobile device, for example a smartphone or a smartwatch, determined by this mobile device; A software module for checking whether a position received from a mobile device corresponds to the position of a singled out visitor; A software module to verify the right of access of said singled out visitor. 15. The system of claim 14, comprising an additional camera (4) for capturing a frontal image of unauthorized visitors in the access area.