WO2024061582A1 - Method for operating an authentication system, and authentication system having exactly one uwb module - Google Patents

Abstract

The invention relates to a method for operating an authentication system (1) of a vehicle (3) for authenticating a portable authentication device (2) to the vehicle (3) in order to release vehicle functions for an operator (4), wherein the authentication system (1) comprises the portable ID provider (2) and a vehicle-side authentication arrangement (5) connected to a control device (12) of the vehicle (3), wherein the authentication arrangement (5) comprises exactly one UWB module (11) with at least one UWB antenna (6), the method comprising at least the following steps: A) actuating the UWB antenna (6) to carry out UWB communication between the portable authentication device (2) and the authentication arrangement (5); B) carrying out the UWB communication between the portable authentication device (2) and the authentication arrangement (5); C) determining a distance from the UWB antenna (6) to the portable authentication device (2) in the UWB module (11); D) checking, in the UWB module (11), whether the distance is shorter than a predefined maximum distance, and transmitting the result of the check to the control device (12) or transmitting the distance to the control device (12) and checking, in the control device (12), whether the distance is shorter than the predefined maximum distance.

Description

Method for operating an authentication system and authentication system with exactly one UWB module

Description:

The invention relates to a method for operating an authentication system of a vehicle for authenticating a portable authentication device, in particular an ID transmitter, with exactly one UWB module with at least one UWB antenna being provided on the vehicle side. In particular, the invention relates to an authentication system with which an authentication of a portable authentication device, in particular an ID transmitter, can be carried out relative to the vehicle in order to release vehicle functions for an operator who carries the portable authentication device, i.e. in particular the ID transmitter, with him.

A wide variety of keyless entry systems are known from the prior art, which use both low-frequency (LF) and high-frequency systems. quent (HF) radio waves. The combination using LF/HF systems is also known from the prior art.

In radio-based authorization systems, security, especially against compromise of the radio communication carried out, is of crucial importance. As part of the release of a vehicle function using portable ID transmitters or portable authentication devices, the determination of a position, a distance or distance or a similar size, for example to check the plausibility of the bidirectional communication carried out, is known from the prior art.

For example, DE 10 2017 109 293 A1 or US 11,277,742 B2, which comes from the same patent family, teaches a method and an associated system in which radio communication takes place one after the other between the ID transmitter or portable authentication device and various UWB antennas and the Signal transit time is evaluated in a central control unit.

However, since, according to this teaching, several UWB antennas are used one after the other and the signal transit times are determined serially in a central control device, such a method is comparatively lengthy and error-prone.

It is therefore the object of the present invention to overcome the aforementioned disadvantages and to improve known authentication methods, particularly with regard to the communication between the authentication device and the vehicle, so that secure but at the same time fast authentication is made possible.

The object is achieved according to the invention by a method with the features of patent claim 1 and by an authentication system with the features of the independent patent claim. The method provides that an authentication system of a vehicle is operated in order to authenticate a portable authentication device and in particular a portable ID transmitter to the vehicle. The authentication serves the purpose of releasing a vehicle function for an operator who, in particular, is carrying the portable authentication device or the portable ID transmitter or is approaching it.

The authentication system includes the portable authentication device, which is designed in particular as a portable ID transmitter, and a vehicle-side authentication arrangement. The authentication arrangement includes exactly one UWB module with at least one UWB antenna, preferably exactly one UWB antenna. The authentication arrangement or the one UWB module is connected to a vehicle-side control device, which is in particular an ECU, which can be designed to control the authentication arrangement to carry out the method. Furthermore, the UWB module itself or a unit formed by the UWB module and the control device or the vehicle-side authentication arrangement can also be a control unit (ECU) or integrated into one. The procedure provides for at least the following steps:

A) controlling the UWB antenna to carry out UWB communication between the portable authentication device and the authentication arrangement, in particular without the UWB antenna or the UWB module to be controlled having to be previously determined separately, selected from a list or according to rules;

B) performing the UWB communications between the portable authentication device and the authentication device;

C) Determining a distance of the UWB antenna to the portable authentication device in the UWB module, in particular by detecting a Duration of a UWB signal of the UWB communication between the portable authentication device and the UWB antenna;

D) Checking in the UWB module whether the distance is less than a predetermined maximum distance and transmitting the result of the test to the control device (ECU of the vehicle).

Alternatively, step D) can be: transmitting the distance to the control device and checking in the control device whether the distance is smaller than the predetermined maximum distance.

A portable authentication device is preferably understood to mean that it can be moved relative to the vehicle-side authentication arrangement. Accordingly, the portable authentication device can be a key or "smart key", a mobile phone, a fob or "smart fob" but also a stationary transmitter, which, for example, is fixed, i.e. stationary, on or in a garage, a charging station or a petrol pump is installed.

Compared to the prior art, the present invention differs in particular in that exactly one UWB module is used, which does not have to be processed or used according to a preselection or according to a list. Rather, only exactly one UWB module of the authentication arrangement is used. Furthermore, at least the determination of the distance is not carried out centrally in a central control device, but rather decentrally in the UWB module.

Since the UWB module does not have to be selected according to a list or according to predetermined rules and does not have to be attempted several times, authentication is faster. The distance determination is also integrated into the UWB module, so that processing in the vehicle-side control device can be simplified accordingly. Since only a single UWB module or a single UWB antenna is used, the authentication arrangement requires comparatively little energy.

Another aspect of the method according to the invention is based on the use of ultra-wideband communication.

In principle, the use of ultra-wideband radio signals (UWB radio signals) for some applications is known from the prior art. However, market-ready transceivers have only recently become available for use.

Ultra-wideband technology is a short-range radio communication that is based on sending short signal pulses that cover a large number of frequencies within a wide frequency bandwidth. The breadth of the frequency ranges covered depends in particular on the regulatory requirements of the relevant territorial area.

A disadvantage of UWB communication in relation to established LF and/or HF communication is the comparatively high energy requirement of many currently available transceivers suitable for UWB communication, which in the present case is reduced accordingly by using only a single UWB module .

However, UWB communication has the fundamental advantage that, based on the emission of pulses, a distance determination is carried out using a transit time-based approach, which is often referred to as the time-of-flight method.

For example, the distance between the UWB antenna and the portable authentication device or the ID transmitter can be determined, by sending a UWB signal from the UWB antenna to the portable authentication device, a UWB transceiver of the portable authentication device answers this and a unit coupled to the UWB antenna in the UWB module, for example a control means, evaluates the detected response signal. This is done by evaluating the time elapsed between sending and receiving. The distance to the portable authentication device, the processing time within the portable authentication device and the distance from the portable authentication device to the UWB antenna are taken into account. If, as in this example, the transit time is evaluated on the vehicle side, only the processing time within the portable authentication device needs to be stored on the vehicle side, i.e. in particular in the UWB module, or be retrievable from the UWB module, so that a corresponding correction of the time measured on the vehicle side between sending the UWB signal and reception of the UWB response can be made.

Experience has shown that the accuracy of a UWB-based distance determination carried out in this way is significantly higher for the usual intended magnitudes of distances than is the case with other methods such as determining the signal strength of LF signals or the triangulation of LF signals. The accuracy of UWB-based distance determinations is often in the order of 10 to 20 cm.

Because the pure transit time of the UWB signal is relatively short compared to the processing time, additional processing of the signal, for example for manipulation of the signal as part of a relay station attack, would be necessary due to the unexpectedly long total time between sending out a UWB signal. Signal and arrival of the corresponding response can be recognized. Compromises, for example like this Relay station attacks are therefore only possible using very complex methods, if at all.

Another advantage of using UWB signals is that, due to the large number of frequencies used, shadowing of the signals is very unlikely. This is because there is a high probability that there will always be a line of sight between the transmitter and receiver for at least some of the frequencies used at the same time. One reason for this is that diffraction effects or reflections can be expected for some frequencies.

As described, the UWB antenna is part of a UWB module, which can in particular be a UWB transceiver. This allows for a compact structure and simple configuration.

If the distance or transit time of the UWB signal is smaller than a predetermined maximum distance or transit time, it can be assumed on the vehicle side that no extension of the bidirectional UWB communication carried out has been carried out. The maximum distance or transit time can, depending on security needs, be adjusted in such a way that, on the one hand, a sufficiently high accuracy of the distance determination is possible, and on the other hand it can be assumed that the UWB signal has been compromised within the recorded maximum distance or transit time can be excluded or largely excluded.

LF and/or HF and/or BLE signals can also be used to determine the distance, with the UWB module being assigned a corresponding interface, which can also be provided integrally in the UWB module. Another approach can, for example, be based on using data from a proximity sensor. For example, a proximity sensor already provided in the vehicle or a proximity sensor arranged on the vehicle specifically for this purpose can output a proximity signal when the operator approaches, which is detected by a control means coupled to the proximity sensor and preferably provided in the UWB module, whereupon the control means the associated UWB antenna of the UWB module.

Advantageous and/or preferred developments of the invention are also mentioned in the subclaims.

A further aspect of the invention relates to an authentication system of a vehicle for authenticating a portable authentication device or an ID transmitter relative to the vehicle for releasing vehicle functions for an operator who carries the portable authentication device or the ID transmitter. The authentication system is designed according to the independent claim and is intended in particular to carry out the method according to the invention.

The features disclosed above can be combined in any way, as long as this is technically possible and they do not contradict each other.

Other advantageous developments of the invention are characterized in the subclaims or are described in more detail below together with the description of the preferred embodiment of the invention with reference to the figures. They show:

Fig. 1 is a schematic representation of an authentication system;

2 shows a flowchart of an exemplary process sequence of the method according to the invention; Fig. 3 is a flowchart of an alternative process sequence of the method according to the invention.

The figures are exemplary schematic. The same reference numbers in the figures indicate the same functional and/or structural features.

1 shows an authentication system 1 with which the method according to the invention can be carried out. The authentication system 1 is used to authenticate a portable authentication device 2 designed as an ID transmitter against a vehicle 3. Fig.

I shows a situation in which the ID transmitter 2 is in the possession of an operator 4. With the method according to the invention, the portable ID transmitter 2 can be authenticated relative to the vehicle 3 so that the operator 4, who carries the portable ID transmitter 2 with him, can access vehicle functions, such as starting the vehicle 3 or a Opening one or more of the vehicle doors.

In addition to the portable ID transmitter 2, the authentication system 1 comprises a vehicle-side authentication arrangement 5. The authentication arrangement 5 has exactly one UWB module 11 with, for example, exactly one UWB antenna 6. In the embodiment shown, the UWB antenna 6 is provided as an integral element of the UWB module 11 designed as a UWB transceiver.

The authentication arrangement 5 also has an LF interface 8 with at least one LF antenna and a proximity sensor 10. Alternatively or additionally, an HF and/or a BLE interface could also be provided. The LF interface 8 is in the UWB module

II integrated, but could also be provided separately from this and only coupled to the UWB module 11 for signaling purposes. The proximity sensor 10 is, for example, on the vehicle roof Underbody assembly or arranged within a door handle of, for example, the left front vehicle door or the driver's door.

In the embodiment shown, the UWB module 11, designed as a UWB transceiver, and the LF interfaces 8 are designed integrally with one another and coupled to the proximity sensor 10 via a signal line. Furthermore, the UWB module 11 is coupled to a motor vehicle control device 12 (ECU). The motor vehicle control device 12 is suitable for controlling and monitoring a method according to the invention and its developments as a control means of the authentication arrangement.

In the exemplary process sequence of the method according to the invention, as shown in FIG. 2, a determination of specific UWB modules 11 for communication can be omitted, since the one existing UWB module 11 is used directly. The process sequence can, for example, take place in response to an actuation of a proximity sensor 10 or as a result of pollen, although this is of secondary importance for the basic functionality of the process sequence shown.

According to Figure 2, the UWB antenna 6 of the UWB module 11 is in a first step 203 immediately moved from a state not ready to send and / or receive into a state ready to send, by the UWB antenna 6 from the UWB module 11 and is controlled in particular by means of the central control device 12.

The UWB antenna 6 sends a UWB signal to the ID transmitter 2. The UWB signal is then received by a UWB transceiver of the ID transmitter 2 and answered with a UWB response signal. The signal is received by the UWB antenna 6 in step 204. Directly in the UWB module 11 and in particular without involving the vehicle-side control device 12, the distance or the transit time of the signal is determined, which the UWB signal on the way to the ID transmitter 2 and additionally the return path from the ID transmitter 2, whereby a corresponding calculation time within the ID transmitter 2 is known to the UWB module 11 or can be called up by the UWB module 11 at the control device 12 and can therefore be calculated out of the actually recorded time period .

In step 205, the distance or transit time is calculated by the UWB module 11 and, if necessary, passed on to the central control device 12.

In step 206, either the UWB module 11 or the central control device 12 checks directly whether the distance or transit time of the UWB signal is smaller than a predetermined maximum distance or transit time. If the test is carried out by the UWB module 11, the result is passed on to the control device 12. If the determined value is less than the maximum value, the ID transmitter 2 for the authentication system 1 is considered to be located within the room in which the vehicle function can be released (Secure Bubble). Furthermore, the signal is not considered to have been compromised, for example through a relay station attack. However, if it is determined in step 206 that the distance or transit time is greater than the predetermined maximum distance or transit time, the procedural sequence of steps 203 to 206 is repeated starting with step 203.

Steps 203 to 206 can be repeated several times, with an abort occurring at the latest when a predetermined number of repetitions has been reached or the ID transmitter 2 can be viewed as being within the predetermined space.

The process sequence shown in Fig. 3 differs from the process sequence shown in Fig. 2 in that in step 201 an approach of the operator 4 is detected by the proximity sensor 10. In step 202, the proximity sensor 10 outputs a proximity signal to the UWB module 11 or to the central control device 12, which then forwards it to the UWB module 11.

If the proximity sensor 10 is not already assigned directly to the UWB module 11, the control device 12 of the authentication arrangement 5 recognizes which of the proximity sensors 10 has detected the approach. In the sequence of procedures shown, the proximity sensor 10 has detected an approach, which is why steps 203 to 207 are carried out analogously to the procedure according to FIG. The implementation of the invention is not limited to the preferred exemplary embodiments given above. Rather, a number of variants are conceivable, which make use of the solution presented even in fundamentally different designs.

Claims

Claims Method for operating an authentication system (1) of a vehicle (3) for authenticating a portable authentication device, in particular a portable ID transmitter (2) towards the vehicle (3) to enable vehicle functions for an operator (4), which in particular carries the portable authentication device (2), the authentication system (1) comprising the portable authentication device (2) and a vehicle-side device connected to a control device (12) of the vehicle (3) or integrated into the control device (12). integrated authentication arrangement (5), wherein the authentication arrangement (5) comprises exactly one UWB module (11) with at least one UWB antenna (6), the method comprising at least the following steps: A) controlling the UWB antenna (6) to carry out UWB communication between the portable authentication device (2) and the authentication arrangement (5); B) carrying out the UWB communication between the portable authentication device (2) and the authentication arrangement (5); C) determining a distance of the UWB antenna (6) to the portable authentication device (2) in the UWB module (11); D) checking in the UWB module (11) whether the distance is smaller than a predetermined maximum distance, and transmitting the result of the test to the control device (12) or transmitting the distance to the control device (12) and Check in the control device (12) whether the distance is smaller than the specified maximum distance. Method according to Claim 1, wherein the distance is determined by detecting a transit time of a UWB signal of the UWB communication between the portable authentication device (2) and the UWB antenna (6). Method according to one of claims 1 or 2, wherein the authentication arrangement (5) in the UWB module (11) has an LF interface (8) which is assigned to the UWB antenna (6), wherein LF communication with a LF signal is carried out between the portable authentication device (2) and the LF interface (8), the portable authentication device (2) detecting a signal strength of the LF signal and sending the signal strength to the UWB module (11) of the authentication arrangement (5 ) is transmitted, with the UWB module (11) determining the distance from the signal strength. Method according to one of the preceding claims, wherein the authentication arrangement (5) in the UWB module (11) has an HF interface which is assigned to the UWB antenna (6), wherein HF communication with an HF signal between the portable authentication device (2) and the HF interface, the portable authentication device (2) detecting a signal strength of the HF signal and transmitting the signal strength to the UWB module (11) of the authentication arrangement (5), whereby the UWB module (11) determines the distance from the signal strength. 5. The method according to any one of the preceding claims, wherein the authentication arrangement (5) in the UWB module (11) has a BLE interface which is assigned to the UWB antenna (6), wherein BLE communication with a BLE signal between the portable authentication device (2) and the BLE interface, the portable authentication device (2) detecting a signal strength of the BLE signal and transmitting the signal strength to the UWB module (11) of the authentication arrangement (5), the UWB module (11) determines the distance from the signal strength. 6. The method according to any one of the preceding claims, wherein the authentication arrangement (5) has at least one proximity sensor (10), which is assigned to the UWB module (11), wherein when the respective proximity sensor (10) detects an approach by the operator (4 ) detected, this proximity sensor (10) outputs a proximity signal identifying the proximity sensor (10), and that the UWB module (11), when it detects the proximity signal, controls the UWB antenna (6) to carry out UWB communication between the portable authentication device (2) and the authentication arrangement (5) prepared according to step A). 7. The method according to any one of the preceding claims, wherein carrying out the UWB communication at least temporarily takes place in parallel with carrying out LF communication and/or HF communication and/or BLE communication. Method according to one of the preceding claims, wherein UWB signal transit times between the UWB antenna (6) of the UWB module (11) and the portable authentication device (2) recorded to enable vehicle functions are considered valid for a minimum period of time, and that during the Minimum period of time, no UWB communication from the UWB module (11) or only UWB communication is carried out to reset the minimum period of time and thereby extend the validity. Authentication system (1) of a vehicle (3) for authenticating a portable authentication device, in particular an ID transmitter (2), to the vehicle (3) for releasing vehicle functions for an operator (4) who carries the portable authentication device (2). , wherein the authentication system (1) has the portable authentication device (2) and a vehicle-side authentication arrangement (5), wherein the portable authentication device (2) has at least one authentication device-UWB interface with an authentication device-UWB antenna and the authentication arrangement (5 ) has exactly one UWB module (11) with at least one UWB antenna (6), and wherein the authentication device UWB interface and the UWB module (11) are set up for UWB communication with one another, the UWB module ( 11) of the authentication arrangement (5) is set up, a method according to one of the preceding applications to carry out sayings.