Method for operating an authentication system, and authentication system having a plurality of UWB antennas
Patent Information
- Application Number
- EP2023751625
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-09-21
- Filing Date
- 2023-08-02
- Publication Date
- 2025-02-05
AI Technical Summary
Existing authentication systems using multiple UWB antennas are lengthy and error-prone due to serial processing of signal transit times in a central control unit, which compromises security and efficiency.
A method utilizing a large number of UWB modules with decentralized distance determination, where all available modules are used simultaneously according to predetermined rules, eliminating the need for preselection based on signal strengths, and integrating distance determination within each module for parallel processing.
This approach results in faster, more secure, and reliable authentication by simplifying processing in the vehicle-side control device, enhancing fault tolerance and resilience, while maintaining high accuracy in distance determination.
Smart Images
Figure 1.1
Abstract
Description
[0001] Marquardt GmbH
[0002] P 059 PCT
[0003] Method for operating an authentication system and authentication system with a plurality of UWB antennas
[0004] Description:
[0005] 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, wherein a plurality of UWB modules, each with at least one UWB antenna, is provided on the vehicle. In particular, the invention relates to an authentication system with which a portable authentication device, in particular an ID transmitter, can be authenticated to the vehicle in order to enable vehicle functions for an operator who carries the portable authentication device, in particular the ID transmitter.
[0006] REVISED SHEET (RULE 91) ISA / EP A wide variety of keyless entry systems are known from the state of the art, which can use both low-frequency (LF) and high-frequency (HF) radio waves. Combining LF / HF systems is also known from the state of the art.
[0007] In radio-based authorization systems, security is of crucial importance, especially against compromise of the radio communication being carried out. When enabling a vehicle function using portable ID transmitters or portable authentication devices, the determination of a position, a distance, or a similar value, for example, to verify the plausibility of the bidirectional communication being carried out, is known from the state of the art.
[0008] For example, DE 10 2017 109293 A1 and US 11,277,742 B2, which comes from the same patent family, teach a method and an associated system in which radio communication takes place successively between an ID transmitter or portable authentication device and various UWB antennas and the signal propagation time is evaluated in a central control unit.
[0009] However, since according to this teaching several UWB antennas are used one after the other and the signal propagation times are determined serially in a central control device, such a method is comparatively lengthy and error-prone.
[0010] The object of the present invention is therefore to overcome the aforementioned disadvantages and to improve known authentication methods, particularly with regard to communication between the authentication device and the vehicle, thus enabling secure yet rapid authentication. This object is achieved according to the invention by a method having the features of patent claim 1 and by an authentication system having the features of the independent patent claim.
[0011] The method provides for operating an authentication system of a vehicle to authenticate a portable authentication device, and in particular a portable ID transmitter, to the vehicle. The authentication serves the purpose of enabling a vehicle function for an operator who, in particular, carries the portable authentication device or the portable ID transmitter with them or approaches them.
[0012] The authentication system comprises the portable authentication device, which is particularly designed as a portable ID transmitter, and a vehicle-mounted authentication arrangement. The authentication arrangement comprises a plurality of UWB modules, each with at least one, and preferably precisely one, UWB antenna. The authentication arrangement or UWB modules are connected to a vehicle-mounted control device, which is particularly an ECU, which can be configured to control the authentication arrangement to execute the method. Furthermore, the UWB module itself or a unit formed by the UWB module and the control device, or the vehicle-mounted authentication arrangement, can be a control unit (ECU) or integrated into one. The method provides at least the following steps:
[0013] A) controlling all UWB antennas to perform one or more UWB communications between the portable authentication device and the authentication arrangement or controlling a plurality of predetermined UWB antennas to perform one or more UWB communications between the portable authentication device and the authentication arrangement;
[0014] B) performing UWB communications between the portable authentication device and the authentication arrangement;
[0015] C) determining a respective distance of the respective UWB antenna to the portable authentication device in each UWB module, in particular by detecting a propagation time of a UWB signal of the UWB communication between the portable authentication device and the respective UWB antenna;
[0016] D) Check in each UWB module whether the respective distance is less than a specified maximum distance and transmit the result of the check to the control unit (ECU of the vehicle).
[0017] A portable authentication device is preferably understood to be movable relative to the vehicle-mounted authentication arrangement. Accordingly, the portable authentication device can be a key or "smart key," a mobile phone, a fob or "smart fob," or even a stationary transmitter, which is, for example, permanently installed (i.e., stationary) on or in a garage, a charging station, or a gas pump.
[0018] The present invention differs from the prior art in particular in that a plurality of UWB modules, each with at least one UWB antenna, are used. However, these modules are not processed or used according to a preselection or according to a list that has yet to be determined. Rather, all available or existing UWB modules of the authentication arrangement are used, or multiple UWB modules are used according to predetermined and immutable rules, for which it is not necessary to consider signal strengths or the like before the actual communication. Furthermore, at least the determination of the distance is then carried out not centrally in a central control device, but decentrally in each of the UWB modules.
[0019] Since the UWB modules do not have to be selected according to a yet-to-be-determined list or according to yet-to-be-determined signal strengths, and therefore multiple communication attempts are not required, authentication is faster. Furthermore, distance determination is integrated into the respective UWB module, so that the distances can be determined in parallel and do not have to be performed slowly one after the other or in parallel with enormous computational effort in a central control unit. This simplifies processing in the vehicle-side control unit. The simultaneous use of a large number of UWB modules also results in increased reliability and thus fault tolerance and resilience.
[0020] If the method is carried out or the above steps are run through multiple times, different UWB modules can be used in each run depending on the predetermined and fixed rules or lists. With three UWB modules, for example, a first and second UWB module can be used in a first run, the first and third UWB modules in a second run, and the second and third UWB modules in a third run. In a fourth run, for example, all three UWB modules can be used. In the subsequent three runs, for example, one of the UWB modules could be used each time. The assignment of which UWB module is used in which run is in particular fixed or determined by the fixed list or the fixed rules. A further aspect of the method according to the invention is based on the use of ultra-wideband communication.
[0021] In principle, the use of ultra-wideband (UWB) radio signals for some applications is well known from the state of the art. However, commercially available transceivers for such applications have only recently become available.
[0022] Ultra-wideband technology is a short-range radio communication technology based on the transmission of short signal pulses, covering a wide range of frequencies within a wide frequency bandwidth. The width of the covered frequency ranges depends primarily on the regulatory requirements of the respective territorial area.
[0023] A disadvantage of UWB communication compared to established LF and / or HF communication is the comparatively high energy consumption of many currently available transceivers suitable for UWB communication.
[0024] However, UWB communication has the fundamental advantage that, due to the transmission of pulses, a distance determination is carried out using a time-of-flight-based approach, which is often referred to as the time-of-flight method.
[0025] For example, the distance between a respective UWB antenna and the portable authentication device or the ID transmitter can be determined by sending a UWB signal from the respective UWB antenna to the portable authentication device, a UWB transceiver of the portable authentication device responds to this signal, and a unit coupled to the UWB antenna in the respective UWB module, for example a control device, evaluates the detected response signal. This is done by evaluating the time elapsed between transmission and reception. The distance to the authentication device, the processing time within the authentication device, and the distance from the authentication device to the respective UWB antenna are taken into account. If, as in this example, the propagation time is evaluated on the vehicle side, only the processing time within the authentication device on the vehicle side, i.e.In particular, it must be stored in each UWB module or be accessible by each UWB module so that the time measured on the vehicle side between transmission of the UWB signal and reception of the UWB response can be corrected accordingly.
[0026] Experience has shown that the accuracy of such a UWB-based distance determination is significantly higher for the typically intended ranges than is the case with other methods, such as signal strength determination of low-frequency signals or triangulation of low-frequency signals. The accuracy of UWB-based distance determinations is often on the order of 10 to 20 cm.
[0027] Because the pure propagation time of the UWB signal is relatively short compared to the processing time, any additional processing of the signal, for example, for manipulation of the signal as part of a relay station attack, would be detected due to the unexpectedly long total time between the transmission of a UWB signal and the arrival of the corresponding response. Compromises, for example, in the form of relay station attacks, are therefore only possible, if at all, with very complex methods.
[0028] Another advantage of using UWB signals is that, due to the large number of frequencies used, signal shadowing is very unlikely. This is because, for at least some of the frequencies used simultaneously, there is a high probability that there will always be a line of sight between the transmitter and receiver. One reason for this is that diffraction effects or reflections can be expected for some frequencies.
[0029] As described, each UWB antenna is part of a respective UWB module, which can in particular be a UWB transceiver. This allows for a compact design and simple configuration.
[0030] If the distance or propagation time of the UWB signal is less than a specified maximum distance or propagation time, the vehicle can assume that the bidirectional UWB communication has not been extended. Depending on security requirements, the maximum distance or propagation time can be adjusted to ensure a sufficiently high degree of distance determination accuracy, while also assuming that compromise of the UWB signal can be ruled out or largely ruled out within the detected maximum distance or propagation time.
[0031] LF and / or HF and / or BLE signals can also be used to determine the distance, whereby, for example, a part of the UWB modules and preferably each UWB module is assigned a corresponding interface, which can also be provided integrally in the respective UWB module.
[0032] Another approach can, for example, be based on using data from one or more proximity sensors. For example, a proximity sensor already provided in the vehicle or a proximity sensor arranged on the vehicle specifically for this purpose can emit a proximity signal when the operator approaches. This signal is detected by a control means coupled to the proximity sensor and preferably provided in at least one of the UWB modules. The control means then controls the associated UWB antenna of the respective UWB module.
[0033] A proximity sensor can also be coupled to multiple UWB modules. Multiple proximity sensors can each be assigned to one UWB module or to multiple UWB modules.
[0034] Advantageous and / or preferred developments of the invention are also mentioned in the subclaims.
[0035] A further aspect of the invention relates to a vehicle authentication system for authenticating a portable authentication device or ID transmitter to the vehicle for enabling vehicle functions for an operator carrying the portable authentication device or ID transmitter. The authentication system is designed according to the independent claim and is intended in particular for implementing the method according to the invention.
[0036] The features disclosed above can be combined as desired, as long as this is technically possible and they do not contradict each other.
[0037] Other advantageous developments of the invention are characterized in the subclaims or are presented in more detail below, together with the description of the preferred embodiment of the invention, with reference to the figures. They show:
[0038] Fig. 1 is a schematic diagram of an authentication system;
[0039] Fig. 2 is 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.
[0040] The figures are schematic examples. Identical reference numerals in the figures indicate identical functional and / or structural features.
[0041] Fig. 1 shows an authentication system 1 with which the method according to the invention can be carried out. The authentication system 1 serves to authenticate a portable authentication device 2 designed as an ID transmitter to a vehicle 3. Fig.
[0042] I shows a situation in which the ID transmitter 2 is in the possession of an operator 4. The method according to the invention can be used to authenticate the portable ID transmitter 2 to the vehicle 3 so that the operator 4, who carries the portable ID transmitter 2, can access vehicle functions, such as starting the vehicle 3 or opening one or more of the vehicle doors.
[0043] The authentication system 1 comprises, in addition to the portable ID transmitter 2, a vehicle-mounted authentication arrangement 5. The authentication arrangement 5 has a plurality of UWB modules 11, in this case two UWB modules 11, each with, for example, exactly one UWB antenna 6. In the embodiment shown, the UWB antenna 6 is designed as an integral element of the respective UWB module embodied as a UWB transceiver.
[0044] II is provided.
[0045] The authentication arrangement 5 further comprises, for each UWB module 11, an LF interface 8 with at least one LF antenna and a proximity sensor 10, for example. Alternatively or additionally, an HF and / or a BLE interface could also be provided. The LF interface 8 is integrated into the associated UWB module 11, but could also be provided separately and only signal-coupled to the respective UWB module 11. The proximity sensor 10 is arranged, for example, on the vehicle roof, on an underbody assembly, or within a door handle of, for example, the left front vehicle door or the driver's door.
[0046] In the embodiment shown, the UWB modules 11 designed as UWB transceivers and the LF interfaces 8 are formed integrally with each other and coupled to the proximity sensor 10 via a signal line.
[0047] In this case, each UWB module 11 can be coupled to a respective proximity sensor 10. As shown, alternatively, a proximity sensor 10 can also be coupled to all or at least several UWB modules 11. If multiple proximity sensors 10 are provided, they can communicate with each other and with the UWB modules 11, for example, via a bus. Furthermore, the UWB modules 11 are coupled to a motor vehicle control unit 12 (ECU), which in turn can be implemented via a single signal line or a bus system. The motor vehicle control unit 12 is suitable for controlling and monitoring a method according to the invention and its further developments as the control means of the authentication arrangement.
[0048] 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 all or at least those UWB modules 11 provided according to the fixed list or the fixed rules are used directly. The process sequence can, for example, occur in response to an actuation of a proximity sensor 10 or as a result of polling, although this is of secondary importance for the basic functioning of the process sequence shown.
[0049] According to Figure 2, as predetermined by a fixed list, in a first step 203 both the UWB antenna 6, for example of the left-hand UWB module 11 in Figure 1, and the UWB antenna 6, for example of the right-hand UWB module 11 in Figure 1, are immediately switched from a non-transmitting and / or non-receiving state to a transmitting state by controlling the UWB antennas 6 from the respective UWB module 11 and in particular by means of the central control device 12.
[0050] The UWB antennas 6 transmit a respective UWB signal to the ID transmitter 2 simultaneously or with a minimal time delay. The respective UWB signal is then received by a UWB transceiver of the ID transmitter 2 and each responded to with a UWB response signal. The signals are received by the respective UWB antennas 6 in step 204. Directly in the respective UWB module 11 and in particular without involving the vehicle-side control device 12, the distance or the propagation time of the signal required by the respective UWB signal on the outward path to the ID transmitter 2 and additionally on the return path from the ID transmitter 2 is determined, wherein a corresponding calculation time within the ID transmitter 2 is known to the respective UWB module 11 or can be retrieved by the respective UWB module 11 from the control device 12 and can thus be deducted from the actually recorded time period.
[0051] In step 205, the respective distance or the respective travel time is calculated by the respective UWB module 11 and optionally passed on to the central control device 12.
[0052] In step 206, the respective UWB module 11 checks directly whether the respective distance or the propagation time of the UWB signal is less than a predetermined maximum distance or propagation time. The result is then passed on to the control device 12. If the determined value is less than the maximum value, the ID transmitter 2 is considered by the authentication system 1 to be located within the space in which release of the vehicle function is possible (secure bubble). Furthermore, compromise of the signal, for example by a relay station attack, is considered not to have occurred. If, on the other hand, it is determined in step 206 that the distance or propagation time for each UWB module 11 in particular is greater than the predetermined maximum distance or propagation time, the process sequence of steps 203 to 206 is repeated, beginning with step 203, wherein other UWB modules 11 oronly individual UWB modules 11 can be controlled.
[0053] Steps 203 to 206 are repeated, in particular, according to the predetermined list or the predetermined rules for the respective UWB antennas 6 or UWB modules 11 provided. Termination occurs at the latest when this is provided for according to the list or the rules or when the ID transmitter 2 is considered to be within the specified area.
[0054] 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 at least one and preferably both UWB modules 11 or to the central control device 12, which then forwards this signal to at least one and preferably both UWB modules 11.
[0055] If the proximity sensor 10 is not already directly assigned to one of the UWB modules 11, the control device 12 of the authentication arrangement 5 or the UWB modules 11 themselves detect which of the proximity sensors 10 has detected the approach. In the process sequence shown, the proximity sensor 10 has detected an approach, which is why steps 203 to 207 are performed analogously to the procedure according to Figure 2.
[0056] The invention is not limited to the preferred embodiments described above. Rather, a number of variants are conceivable that utilize the presented solution even in fundamentally different embodiments.
Claims
Patent 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), with the vehicle (3) for enabling vehicle functions for an operator (4) who, in particular, carries the portable authentication device ID-(2), wherein the authentication system (1) comprises the portable authentication device (2) and an authentication arrangement (5) on the vehicle side connected to a control device (12) of the vehicle (3) or integrated into the control device (12), wherein the authentication arrangement (5) comprises a plurality of UWB modules (11), each having at least one UWB antenna (6), wherein the method comprises at least the following steps: A) controlling all UWB antennas (6) to carry out one UWB communication or several UWB communications between the portable authentication device (2) and the authentication arrangement (5) or controlling several predetermined UWB antennas (6) to carry out one UWB communication or several UWB communications between the portable authentication device (2) and the authentication arrangement (5); B) performing the UWB communications between the portable authentication device ID transmitter (2) and the authentication arrangement (5); C) Determining a respective distance of the respective UWB Antenna (6) to the portable authentication device (2) in each UWB module (11); D) Checking in each UWB module (11) whether the respective distance is smaller than a predetermined maximum distance, and transmitting the result of the check to the control device (12). Method according to claim 1, wherein the respective distance is determined by detecting a propagation time of a UWB signal of the UWB communication between the portable authentication device (2) and the respective UWB antenna (6). Method according to claim 1 or 2, wherein it is determined according to a predetermined and fixed list and / or predetermined and fixed rules which of the UWB modules (11) of the plurality of UWB modules (11) are used for steps A) to D), wherein the list and / or the rules are stored in particular in the UWB modules (11) or can be retrieved by them.The method according to claim 3, wherein steps A) to D) are performed several times consecutively during operation of the vehicle (3), and wherein the list and / or rules determine which of the UWB modules (11) are used for a respective run. The method according to one of the preceding claims, wherein the authentication arrangement (5) in each UWB module (11) has an LF interface (8) assigned to the respective UWB antenna (6). wherein a respective LF communication is carried out with an LF signal between the portable authentication device (2) and each LF interface (8), wherein the portable authentication device (2) detects a respective signal strength of the LF signals and transmits the respective signal strength to the respective UWB module (11) of the authentication arrangement (5), wherein each UWB module (11) determines a respective distance from the respective signal strength.Method according to one of the preceding claims, wherein the authentication arrangement (5) in each UWB module (11) has an RF interface which is assigned to the respective UWB antenna (6), wherein a respective RF communication with an RF signal is carried out between the portable authentication device (2) and each RF interface, wherein the portable authentication device (2) detects a respective signal strength of the RF signals and transmits the respective signal strength to the respective UWB module (11) of the authentication arrangement (5), wherein each UWB module (11) determines the respective distance from the signal strength.Method according to one of the preceding claims, wherein the authentication arrangement (5) in each UWB module (11) has a BLE interface which is assigned to the respective UWB antenna (6), wherein a respective BLE communication is carried out with a BLE signal between the portable authentication device (2) and each BLE interface. wherein the portable authentication device (2) detects a respective signal strength of the BLE signals and transmits the respective signal strength to the respective UWB module (11) of the authentication arrangement (5), wherein each UWB module (11) determines the respective distance from the signal strength.
8. The method according to one of the preceding claims, wherein the authentication arrangement (5) has at least one proximity sensor (10), which is assigned to at least one of the UWB modules (11), and in particular each UWB module (11) has a proximity sensor (10), which is assigned to exactly one of the UWB modules (11), wherein, when the respective proximity sensor (10) detects an approach of the operator (4), this proximity sensor (10) outputs a proximity signal identifying the proximity sensor, and in that the assigned UWB module (11), when it detects the proximity signal, initiates the control of the UWB antenna (6) to carry out UWB communication between the portable authentication device (2) and the authentication arrangement (5) according to step A).
9. Method according to one of the preceding claims, wherein the UWB communication is carried out at least temporarily in parallel with the carrying out of an LF communication and / or an HF communication and / or a BLE communication.
10. Method according to one of the preceding claims, wherein for enabling vehicle functions, detected UWB signal propagation times between the respective UWB antenna (6) of the UWB modules (11) and the portable authentication device (2) for a a minimum period of time is considered valid, and that during the minimum period of time, no UWB communication is carried out by the respective 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 enabling vehicle functions for an operator (4) carrying the portable authentication device (2), wherein the authentication system (1) comprises 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 a plurality of UWB modules (11), each with at least one UWB antenna (6), and wherein the authentication device UWB interface and the UWB modules (11) are configured for UWB communication with each other, wherein the UWB modules (11) of the authentication arrangement (5) are configured to carry out a method according to one of the preceding claims.