FI ELD OF TH E I NVENTION

The present invention relates to a method and device for data transfer between a mobile device and a reader device. Specifically, the present invention relates to a method, a reader device, and a mobile system for data transfer between the mobile device and the reader device.

BACKG ROU N D OF TH E I NVENTION

Keyless entry systems have become widely used in applications ranging from vehicle entry systems and vehicle access control systems to building access control. For very close-range applications, a radio-freguency identification ( RFID) transponder (or tag) is often used, which has mostly replaced earlier magnetic stripe cards. Other current solutions use infra red systems or radio systems to transmit an authenticating signal from a user device to a vehicle security system or to a building access device. The authenticating can be initiated either by the user, for instance by pressing a button on the user device, or from the access device itself which periodically transmits reguest signals and awaits a response message.

These current systems involve specific devices for each type of access point, such that users are often reguired to carry several user devices to access their vehicle, their workplace building, their gym and other such access controlled areas. This makes the existing solu- tions of devices and systems inefficient and not very user friendly. As the communicating range between a user device and an access device increases, the convenience and ease-of-use increases, because the user device does not need to be placed in very close range, such as less than one centimeter. However as the range in creases, potential new security issues also arise. This is because, if there are several tran- 5 sponders in the vicinity of a reader device, in a situation such as a gueue, it can become unclear if is indeed the person at the front of the gueue who has the necessary authoriza tion when another authorized user is also within range. Approaches have been introduced to reduce the chance of granting entry to an unauthorized third party. In one approach the chosen freguency can limit the range, for example 1 3.56 M Hz High Freguency ( H F) has a o typical read range of between 1 cm and 1 m. Another approach involves using a technol ogy with a higher range and then evaluating the distance between the reader device and the transponder based on the signal path loss of the received signal. This does not allow a very precise distance measurement because of signal loss and interference due to surfaces, absorption due to air humidity, anisotropic antenna responses, and imprecisely calibrated5 devices.

The maximum allowable distance for authorizing access may be location specific, i.e. for a vehicle access system it might be larger than for an entry-way access system. However, relatively simple relay attacks using signal repeaters or amplifiers can fool the system into granting access, even when the user device and the access device are far apart. This has0 enabled unauthorized access and has left users and providers of access control devices with a need for higher security methods.

WO 201 7/1 55348 A1 describes a mobile device for adapting mobile, portable commu nications devices to security systems, in particular for the key-less activation of an entry system for vehicles, wherein a modular unit is configured such that a communication be tween the mobile device and the security system is possible.

WO 201 7/1 71 21 452 A1 describes a method for distance measurement based on a time difference between a challenge and a response message, wherein the challenge and re- sponse messages are transmitted by a transmission protocol in which the corresponding message is transmitted by a transformed spreading code.

S U M MARY OF TH E I NVENTION

It is an object of this invention to provide a method and device for data transfer between a mobile device and a reader device. In particular, it is an object of the present invention to provide a method and devices for the efficient and secure data transfer between a mobile device and a reader device.

According to the present invention, these objects are achieved through the features of the independent claims. In addition, further advantageous embodiments follow from the de pendent claims. According to the present invention, the above-mentioned objects are particularly achieved in a method of data transfer between a mobile device and a reader device, comprising transmitting, via an ultra-wideband transmission, from an ultra-wideband communica tions module to the reader device, a reguest value. The method further comprises deter mining, by the reader device, a distance between the ultra-wideband communications module and the reader device based on transmission properties of the ultra-wideband transmission. The method further comprises generating, by the reader device, a validation value, using the request value from the ultra-wideband communications module, and transmitting the validation value, via a wireless transmission, from the reader device to the mobile device, if the distance between the ultra-wideband module and the reader device is smaller than a predefined value. The method further comprises verifying, in the mobile device, the validation value using the request value. The method further comprises ena bling, in the mobile device, further data transfer between the mobile device and the reader device, upon affirmative verifying of the validation value.

Ultra-wideband ( UWB) is a communications technology which uses radio waves for short- range, high-bandwidth communications over a large portion of the radio spectrum. Infor- mation is transmitted by generating radio wave pulses at specific time intervals, as opposed to conventional radio systems which transmit information by varying a power level of the radio transmission, or modulating a frequency and/or phase of the transmission. Infor mation can also be modulated on ultra-wideband signals by varying an amplitude, encod ing a polarity, or using orthogonal pulses. In an embodiment the method further comprises transmitting the request value, via a wired or wireless transmission, from the ultra-wideband communications module to the mobile device or vice versa.

In another embodiment of the method, transmitting the request value further comprises determining a distance between the ultra-wideband communications module and the mo- bile device.

In another embodiment the method further comprises using two or more antennas to de termine two or more distances between the ultra-wideband communications module and one of the two or more antennas, respectively. The method further comprises determining whether the ultra-wideband communications module is outside an access controlled area or inside the access controlled area using the two or more distances. The method further comprises generating the validation value only if the ultra-wideband communications module is outside the access controlled area.

In another embodiment of the method, determining a distance uses transmission proper ties including a time difference, an amplitude difference, and /or a phase difference of the ultra-wideband transmission.

In another embodiment of the method, the reguest value and the validation value are dig- itally signed, and verifying the validation value further comprises authenticating the digi tally signed reguest value and the digitally signed validation value by verifying their digital signatures.

In another embodiment of the method, transmitting the validation value from the reader device to the mobile device comprises an ultra-wideband transmission from the reader de- vice to the ultra-wideband communications module and a wired or wireless transmission from the ultra-wideband communications module to the mobile device, and further data transfer between the mobile device and the reader device comprises a wired or wireless transmission between the mobile device and the ultra-wideband communications module, and an ultra-wideband transmission between the ultra-wideband communications module and the reader device.

In addition to the method of data transfer between a mobile device and a reader device, the present invention also relates to a reader device for data transfer with a mobile device. comprising an ultra-wideband transceiver configured to receive, via an ultra-wideband transmission from an ultra-wideband communications module, a reguest value. The device further comprises a processor configured to determine a distance between the ultra-wide band communications module and the reader device based on transmission properties of the ultra-wideband transmission, and to generate a validation value, if the distance be tween the ultra-wideband communications module and the reader device is smaller than a predefined value. The device further comprises a wireless communications module config ured to transmit the validation value to the mobile device, via a wireless transmission, en abling the mobile device to verify the validation value using the reguest value from the ul- tra-wideband communications module, priorto enabling further data transfer between the reader device and the mobile device, via wireless transmission.

In an embodiment the ultra-wideband transceiver further comprises two or more antennas. The processor is further configured to determine two or more distances between the ultra- wideband communications module and one of the antennas, respectively, based on trans- mission properties of the ultra-wideband transmission. The processor is further configured to determine whether the ultra-wideband communications module is outside an access controlled area or inside an access controlled area, using the two or more distances. The processor is further configured to generate a validation value, if the ultra-wideband com munications module is outside the access controlled area.

In an embodiment, the processor is configured to determine a distance using transmission properties including a time difference, an amplitude difference, and /or a phase difference of the ultra-wideband transmission. In another embodiment, the processor is configured to receive a digitally signed reguest value and to transmit a digitally signed validation value.

In another embodiment, the wireless communications module is configured for wireless transmission using Bluetooth ( BT), Bluetooth Low Energy ( BLE), a Wireless Local Area Net- 5 work (WLAN ), ZigBee, Radio Freguency Identification ( RFID), Z-Wave, and/or Near Field Communication ( NFC).

In another embodiment, the ultra-wideband transceiver is further configured to transmit the validation value to the mobile device, via an ultra-wideband transmission from the ul tra-wideband transceiver to the ultra-wideband communications module and a wired or o wireless transmission from the ultra-wideband communications module to the mobile de vice, and wherein the wireless communications module is further configured to enable fur ther data transfer between the reader device and the mobile device, via a transmission be tween the mobile device and an ultra-wideband communications module and an ultra- wideband transmission between the ultra-wideband communications module and the5 reader device.

In addition to a method and device of data transfer between a mobile device and a reader device, the present invention also relates to a mobile system for data transfer with a reader device, comprising an ultra-wideband communications module configured to transmit, via an ultra-wideband transmission, a reguest value to a reader device, enabling the reader0 device to determine a distance between the ultra-wideband communications module and the reader device based on transmission properties of the ultra-wideband transmission. The system further comprises a wireless communications module configured to receive, via a wireless transmission, a validation value from the reader device, transmitted by the reader device, if the distance between the ultra-wideband module and the reader device is smaller than a predefined value. The system further comprises a processor configured to verify the validation value using the reguest value, and upon affirmative verification of the validation value, to enable data transfer with the reader device. In an embodiment, the ultra-wideband communications module is further configured to receive the validation value, via an ultra-wideband transmission from the reader device to the mobile system, and wherein the processor is further configured to enable data transfer between the mobile system and the reader device via an ultra-wideband transmission.

BRI EF DESCRI PTION OF TH E DRAW I NGS The present invention will be explained in more detail, by way of example, with reference to the drawings in which:

Fig. 1 shows a flow diagram illustrating an exemplary seguence of steps for data transfer between a mobile device and a reader device;

Fig. 2 shows a flow diagram illustrating an exemplary seguence of steps for data transfer between a mobile device and a reader device;

Fig. 3 shows a block diagram illustrating schematically a data flow in a system for data transfer between a mobile device and a reader device;

Fig. 4 shows a block diagram illustrating schematically a data flow in a system for data transfer between a mobile device and a reader device; Fig. 5 shows a block diagram illustrating schematically a data flow in a system for data transfer between a mobile device and a reader device, wherein the mobile system comprises a separate ultra-wideband communications module and mobile device; and

5 Fig. 6 shows a block diagram illustrating schematically a data flow in a system for data transfer between a mobile device and a reader device, wherein the mobile system comprises a mobile device with an integrated ultra-wideband commu nications module.

Fig. 7 shows a diagram illustrating schematically a person with an ultra-wideband0 communications module situated, a reader device, and an access controlled area.

Fig. 8 shows a block diagram illustrating schematically a reader device with two an tennas, an ultra-wideband communications module, and an access controlled area. 5 DESCRI PTION OF TH E EM BODI M ENTS

Whenever possible, like reference numbers will be used to refer to like components or parts.

In Figures 1 to 5, reference numeral 3 refers to a mobile device. The mobile device 3 is a portable electronic system such as a smart phone, smart watch, tablet, laptop, or similar device. The mobile device 3 contains a processor 31 and a wireless communication module0 32. The wireless communications module 32 is configured for wireless transmission using Bluetooth ( BT), Bluetooth Low Energy ( BLE), a Wireless Local Area Network (WLAN), ZigBee, Radio Freguency Identification ( RFID), Z-Wave, and/or Near Field Communication ( NFC). The mobile device 3 also contains provisions for wired communication via a socket such as USB, Micro-USB, USB-C, Lightning, or 3.5 mm jack, for use in a wired communi- cation using an appropriate protocol for wired transmission.

In Figures 1 to 8, reference numeral 2 refers to a reader device. The reader device 2 may be fixedly mounted near an access point or specially designated area, such as on a wall or ceiling or in a door itself, or mounted onto a movable item such as a bicycle or vehicle. The reader device comprises an ultra-wideband transceiver 21 , a processor 22, and a wireless communications module 23.

In Figures 1 to 8, reference numeral 1 refers to an ultra-wideband communications module. The ultra-wideband communications module 1 is a hardware device which is either a standalone device not integrated into another device, or a module which is incorporated into a device. The ultra-wideband communications module 1 is comprised of an ultra- wideband transceiver 1 1 , and if embodied in a standalone device further comprises means of communicating with a mobile device, such means including: a wireless communications module 1 2, a cable for wired transmission, and/or a plug for establishing a pluggable con nection with a suitable socket on the mobile device 3. If the ultra-wideband communica tions module 1 is integrated into a mobile device 3, communication with other hardware modules of the mobile device 3 takes place via a wired data bus. The ultra-wideband com munications module 1 may be carried on a user, for example on a keychain, in a pocket of apparel, or in a bag, such that the user may be identified on the basis of their possession of the ultra-wideband communications module 1 . In an embodiment, the ultra-wideband communications module 1 further comprises a signal strength detector for determining a signal strength of a wireless transmission, to establish on the basis of the received signal strength a proximity to the mobile device 3.

In Figures 5 and 6, reference numeral 4 refers to a mobile system. The mobile system 4 comprises the mobile device 3 and the ultra-wideband communications module 1 . In an embodiment the mobile device 3 and the ultra-wideband communications module 1 are integrated into the same device, as outlined in Figure 6. In another embodiment the mobile device 3 and the ultra-wideband communications module 1 are separate devices in prox imity to each other, as outlined in Figure 5. In an embodiment where the ultra-wideband communications module 1 and the mobile system 4 are integrated into the same device, the communication between the mobile system 4 and the reader device 2 takes place via an ultra-wideband transmission T7 or another wireless transmission, as described above.

As shown in Figure 1 , in step S 1 , the ultra-wideband module 1 generates a reguest value. Subseguently, in step S2, the ultra-wideband communications module 1 transmits the re guest value to the mobile device 3. Alternatively, a reguest value is generated in the mobile device 3, as shown in step S 1 In the latter scenario, in step S2', the mobile device 3 sub seguently transmits the reguest value to the ultra-wideband communications module 1 . In both scenarios, the reguest value is generated from: cryptographic keys, hardware infor mation, serial numbers, user credentials, user access rights, and/or time-stamps. The transmission of the reguest value, in steps S2 or S2', takes place via a wireless or a wired transmission T2, T2', respectively.

In case of a wireless transmission, in an embodiment, the receiver of the transmission de termines a distance using a received signal strength. The determined distance is compared to a predefined value to establish whether the ultra-wideband communications module 1 and the mobile device 3 are within a predefined distance. The specific predefined value will depend on a use-case. For example, in the use-case of a user in an access control scenario, the predefined value indicates a relatively short distance, e.g. in a range of 50- 1 00 centi meters, such that it allows a determination of whether the ultra-wideband communica- tions module and the mobile device 3 are being carried by the same user. In the use-case of a vehicle in a parking garage access control scenario where the ultra-wideband commu nications module is integrated in the vehicle the predefined value indicates a greater dis tance, e.g. 3- 1 0 meters, such that it allows a determination of whether the user is situated inside, or close to, the vehicle. A wired transmission T2 or T2' is implemented via a cable, a direct pluggable connection, or via a data bus if the ultra-wideband communications module 1 and the mobile device 3 comprise a single device. In this wired scenario there is no need to determine a distance between the devices 1 and 3.

As illustrated in Figure 1 , in step S3, the reguest value is transmitted from the ultra-wide- band communications module 1 to the reader device 2 in an ultra-wideband transmission. The distance is determined in the reader device, in step S4, based on transmission proper ties of the ultra-wideband transmission T3. The transmission properties include a time dif ference, an amplitude difference, and/or a phase difference. The amplitude difference is the difference in signal amplitude between the signal transmitted by the ultra-wideband communications module 1 and the signal received by the reader device 2. By taking into consideration the attenuation of the signal, the distance between the ultra-wideband com munications module 1 and the reader device 2 is determined. The phase difference is the difference in signal phase between the signal transmitted by the ultra-wideband communications module 1 and the signal received by the reader device 2. By taking into consideration the change in signal phase, the distance between the ultra- wideband communications module 1 and the reader device 2 is determined. It is to be un- derstood that for the amplitude difference and phase difference, alternatively, the signal may also be transmitted by the reader device 2 and received by the ultra-wideband com munications device 1 . In a preferred embodiment, a time difference is used as a basis for determining the distance, as it is more secure against spoofing attacks, wherein a third party may use a radio relay device to gain unauthorized access to a location or system in a so-called "relay-attack". Depending on the embodiment, the time difference is a "one-way time-of-f light" time difference between the ultra-wideband communications module 1 sending the reguest value and the reader device 2 receiving the reguest value, or a "round- trip time-of-flight" time difference, in which a second transmission takes place from the reader device 2 to the ultra-wideband communications module 1 either prior to, or after, the first transmission of the reguest value. In the "one-way time-of-flight" scenario, the ultra-wide-band communications module 1 and the reader device 2 are provided with tightly synchronized clocks for accurately determining the distance. In the latter case of a "round-trip time-of-flight" calculation, there is stored, either in the reader device 2 or the ultra-wideband communications module 1 , an accurate representation of the processing time, i.e. the time it takes between the reception of an ultra-wideband transmission and the sending of a response ultra-wideband transmission, which processing time allows for accurately determining the distance.

In step S5, the reader device 2 generates a validation value, if the determined distance is smaller than a predefined value. The predefined value may be set during manufacture or during commissioning of the access system and adjusted or updated as necessary. In step S6, the validation value is then transmitted to the mobile device 3 via a wireless transmis sion T6, using one of the wireless technologies mentioned above. The mobile device 3 then verifies the validation value, using the reguest value in step S7. If the validation value is affirmatively verified, the mobile device 3 enables data transfer in step S8. In step S9, data transfer between the mobile device 3 and the reader device 2 takes place. This data transfer may comprise sending and /or receiving user credentials, access credentials, location infor mation, codes, passwords, and/or other data. In an access control scenario, this data transfer makes it possible to control and allow a user to gain access to a restricted access area or space or to gain authorization on further devices, appliances, and /or systems. In Figure 2, the seguence for data transfer between the mobile device 3 and the reader device 2 differs from the seguence of Figure 1 in that steps S6 and S9 are replaced by steps S6' and S9', respectively. In step S6' the validation value is transmitted from the reader device 2 to the mobile device 3 in two sub-steps. In a first sub-step S61 , the validation value is transmitted from the reader device 2 to the ultra-wideband communications mod- ule 1 via an ultra-wideband transmission T61 . In a second sub-step S62, the validation value is transmitted from the ultra-wideband communications module 1 to the mobile de vice 3 via a wireless transmission T62. Similarly, in step S9', the data transfer between the mobile device 3 and the reader device 2 takes place via the ultra-wideband communica tions module 1 . In a first sub-step S91 , data transfer between the mobile device 3 and the ultra-wideband communications module 1 occurs in a first transmission T91 , and in a sec ond sub-step S92, data transfer between the ultra-wideband communications module 1 and the reader device 2 occurs in a second transmission T92. This embodiment has the advantage that the reader device 2 does not reguire a wireless communications module

23. Figure 3 illustrates the data transmissions between the ultra-wideband communications module 1 , the reader device 2, and the mobile device 3. The request value is transmitted from the ultra-wideband communications module 1 to the mobile device 3, in transmission T2. In an alternate embodiment, the request value is instead transmitted from the mobile device 3 to the ultra-wideband communications module 1 , in transmission T2'. The request value is transmitted from the ultra-wideband communications module 1 to the reader de vice 2, in transmission T3. The reader device 2 determines the distance between the ultra- wideband communications module 1 and the reader device 2, as described above. If the distance is smaller than a predefined value, the reader device 2 transmits a validation value to the mobile device 3, in a transmission T6. The mobile device 3 then verifies the validation value using the request value as described above, and upon affirmative verification enables data transfer in transmission T9, between the mobile device 3 and the reader device 2.

In Figure 4, the data transmissions between the ultra-wideband communications module 1 , the reader device 2, and the mobile device 3 differ from Figure 3 in that transmissions T6 and T9 are replaced by the transmissions T61 , T62, and T91 , T91 , respectively. In this embodiment, the transmission of the validation value between the mobile device 3 and the reader device 2 takes place between the mobile device 3 and the ultra-wideband commu nications module 1 , in a first transmission T61 , and between the ultra-wideband commu nications module 1 and the reader device 2, in a second transmission T62. Similarly the data transfer between the mobile device 3 and the reader device 2 takes place between the mobile device 3 and the ultra-wideband communications module 1 , in a first transmis sion T91 , and between the ultra-wideband communications module 1 and the reader de vice 2, in a second transmission T92. In Figure 7, a person possessing an ultra-wideband communications module 1 is situated outside an access controlled area 6. A reader device 2 is installed close to the doorway 5. In this embodiment the reader device 2 comprises two antennas 21 1 and 21 2. The ultra- wideband communications module 1 transmits a reguest value in a transmission T3 which is received by both antennas 21 1 and 21 2. The reader device 2 determines two distances between the ultra-wideband communications module 1 and the antennas 21 1 and 21 2, respectively, as described above. The reader device determines whether one or both of the distances is smaller than a predefined value, as described above. The reader device 2 also determines a difference in the two determined distances between antenna 21 2 and the ultra-wideband communications module 1 , and antenna 21 1 and the ultra-wideband communications module 1 . The difference is used to determine whether the ultra-wide band communications module 1 , and therefore by extension the person possessing the ultra-wideband communications module 1 , is inside or outside the access controlled area 6. If the person is inside the access controlled area 6 it is advantageous that the reader device 2 not generate a validation value as it may inadvertently lead to unauthorized access of the access controlled area 6 by other persons. In this embodiment, if the difference is positive, the ultra-wideband communications module 1 is outside the access controlled area 6. If the difference is negative, the ultra-wideband communications module 1 is inside the access controlled area 6. If one or both of the determined distances is smaller than a predefined value and the ultra-wideband communications module 1 is outside the access controlled area 6, the reader device 2 generates a validation value and proceeds as de scribed above.

In further embodiments, arrangements involving three or more antennas can be used for the purposes of higher precision or for determining a spatial position of the ultra-wideband communications module 1 . The spatial position of the ultra-wideband communications module 1 is further used to decide whether or not the reader device 2 generates a valida tion value and proceeds as described above. For example, in combination with further in formation a bout the access controlled area and its surroundings, e.g. a floor plan of a build ing such as a hotel or the like, the spatial position is used to distinguish between positions of the ultra-wideband communications module 1 which are relevant for the reader device 2 to control access, e.g. outside the access controlled area 6 but in front of a door to the accessed controlled area 6, or which are not relevant of for the reader device 2 to control access, e.g. outside the access controlled area 6 but in another room without open access to the door of the accessed controlled area 6. In Figure 8, a reader device 2 is shown schematically comprising an ultra-wideband trans ceiver 21 and a processor 22. The ultra-wideband transceiver 21 further comprises two antennas 21 1 and 21 2. The antennas are arranged such that one antenna 21 2 is between the access controlled area 6 and the other antenna 21 1 . The distance between the anten nas 21 1 and 21 2 must be large enough that a precise difference may be determined, as reguired by desired decision criteria. An ultra-wideband communications module 1 com prises an ultra-wideband transceiver 1 1 which transmits a reguest value in a transmission T3 which is received by both antennas 21 1 and 21 2. The reader device is located next to an access controlled area 6.

It should be noted that, in the description, the seguence of the steps has been presented in a specific order, one skilled in the art will understand, however, that the order of at least some of the steps could be altered, without deviating from the scope of the invention. LIST OF REFERENCE N U M ERALS

1 Ultra-wideband communications module

2 Reader device

3 Mobile device

5 4 Mobile system

5 Doorway

6 Access controlled area

1 1 Ultra-wideband transceiver

1 2 Wireless communications module

0 21 Ultra-wideband transceiver

21 1 Antenna

21 2 Antenna

22 Processor

23 Wireless communications module

5 3 1 Processor

32 Wireless communications module

S 1 , S 1 ' Generate request value

S2, S2' Transmit request value

53 Transmit request value

0 54 Determine distance

55 Generate validation value

S6, S6' Transmit validation value

561 Validation value transfer between the mobile device and the ultra-wide band communications module

5 562 Validation value transfer between the ultra-wideband communications module and the reader device

57 Verifying a validation value

58 Enabling data transfer

S9, S9' Data transfer between the mobile device and the reader device

0 591 Data transfer between the mobile device and the ultra-wideband commu nications module

592 Data transfer between the ultra-wideband communications module and the reader device

T2, T2' Transmission of request value

5 T3 Transmission of request value

T6, T6' Transmission of validation value

T61 Transmission of validation value

T62 Transmission of validation value

T7 Transmission of validation value

0 T9, T9' Data transfer

T91 Data transfer

T92 Data transfer