GB2592851A

GB2592851A - Key fob

Info

Publication number: GB2592851A
Application number: GB1912153.2A
Authority: GB
Inventors: John Thompson Martin; Richard Alan Hawkes Ian
Original assignee: ZF Friedrichshafen AG
Current assignee: ZF Friedrichshafen AG
Priority date: 2019-08-23
Filing date: 2019-08-23
Publication date: 2021-09-15
Also published as: GB201912153D0

Abstract

A key fob signal modification system 100 and method of using the same; the system having a key fob 102 which transmits a key fob signal 106, and a target; wherein when the key fob is in a detectable range of the target the key fob signal is modified. The key fob has a transmitter 114, detector 110 and controller 112; the transmitter being able to transmit a key fob signal, the detector being able to provide a detection signal to the controller when a target is in a detectable range, and the controller being able to cause suppression or modification of the key fob signal when the detection signal is provided by the detector. Communication between the key fob and target may be via NFC, with the target containing an NFC tag 116 detectable by the detector, such as an NFC sticker. The key fob may be configured for use with a vehicle and the key fob signal modifiable to disable functions such as unlock or start-up of the vehicle. Modification of the key fob signal may include alteration of a message conveyed by the signal, while suppression may include the signal not being transmitted.

Description

KEY FOB

The present invention relates to key fob suppression or modification systems and key fobs for use therein, the system and key fob being particularly but not exclusively for use with a vehicle such as a motor vehicle. The invention also relates to methods of suppressing or modifying a key fob signal Remote locking is well-known in the art, especially within the field of motor vehicles, and has been for many years. Here, a signal is transmitted to a vehicle using, for example, short-distance radio transmission from a key fob and the vehicle can therefore be unlocked without physical interaction between a key and a lock. The signal is usually triggered by a button press on the key fob by a user.

More recently, keyless entry, exit, and start-up have become commonplace in the industry. In such a system, no action at all is required by the user in order to unlock the vehicle, with the vehicle automatically unlocking based on the proximity of a key fob to a vehicle. Such systems rely on communication between the vehicle and the key fob. For example, the key fob will receive a signal from the vehicle when it is in the vicinity of the vehicle, which will then result in a response signal to be issued automatically from the key fob in response. The vehicle verifies this signal and unlocks the vehicle accordingly. in many vehicles with these systems, the vehicle can then be started by simply pressing a "start" button on the dashboard of the vehicle. No physical contact between the vehicle and key is ever required.

Unfortunately, such systems are liable to be hacked by nefarious persons seeking to steal vehicles. So-called "man in the middle" attacks can be achieved by using radio equipment to boost the signals between the key and vehicle. For example, one transceiver can be placed at the front door of a house, near to which is placed the key, and another transceiver can be placed near to the vehicle to which the key belongs.

Such a system may fool the vehicle into thinking that the key is proximate to the vehicle, resulting in completion of the signal exchange and unlocking and starting of the vehicle. Other, simpler, systems may simply boost the signal transmitted from the key to the vehicle, with the same overall effect.

Once started, safety concerns prevent the vehicle being switched off even once the key fob is again out of range of the vehicle, thus the vehicle can be driven away successfully by a thief It is desirable to prevent or limit the success of such attacks or other methods of attack that take advantage of inherent vulnerabilities in keyless entry systems, whether or not they are related to vehicles.

According to a first aspect, there is provided a key fob signal suppress on or modification system, comprising: a key fob including a transmitter, a detector, and a controller, the transmitter being configured to transmit a key fob signal and the detector being configured to provide a detection signal to the controller when a target is within a detectable range; and wherein the controller is configured to cause suppression or modification of the key fob signal when the detection signal is provided by the detector.

The key fob may therefore transmit the key fob signal as usual when the target is not within the detectable range, whilst the controller suppresses or modified the key fob signal when the target is within the detectable range. Therefore the signal provided by the key fob is dependent on a separation between the key fob and the target.

The detectable rage of the target may be 100 min or less, or may be 40 mm or less.

By providing a detectable range that is relatively small, it can be ensured that the key fob signal is only modified or suppressed when it is in dose proximity to the target.

The communication between the key fob and the target may be via near-field communication (NFC).

NFC provides the required detectable range and does not require power to be provided to both the key fob and the target.

The target may comprise an NFC tag that is detectable by the detector. Use of a tag allows the adaptation of an object of the choice of the user into a target for use in the present system. The NEC tag may be an NEC sticker, i.e. an adhesive tag with an embedded or surface-mounted NEC device.

When the key fob is configured for use with a vehicle, such as a motor vehicle, the key fob signal may be modifiable to enable or disable one or more functions of the vehicle. Some functions may therefore be allowed to continue even when the key fob is in the vicinity of the target whilst others are prevented. For example, the vehicle may be allowed to be unlocked but may be prevented from being started up, in order to prevent theft.

The one or more functions may include complete unlock, i.e. unlock of every door of the vehicle, partial unlock, i.e. unlock of one or more doors of the vehicle, such as only the boot, or start-up of the vehicle.

The target may be a key tray or other receptacle.

Modification of the key fob signal may include alteration of a message conveyed by the key fob signal. The message conveyed by the signal may be conveyed in any known manner of wireless communication, which will be known to those skilled in the art. For example, the message may change from a "unlock and enable start" message to an "unlock only" message.

Suppression of the key fob signal may include the key fob signal not being transmitted, e.g. the transmitter may be inoperable whilst the target is within the detectable range of the key fob.

The key fob signal before modification or suppression may be an unlock signal.

Receipt of the unlock signal at the vehicle will therefore result in unlocking of the vehicle.

The detector may be configured to poll for the target at set intervals, the suppression or modification of the key fob signal being constant between the set intervals.

By polling at set intervals, power can be saved by not continuously checking for the target. As the key fob signal is kept constant between polls, the security of the system can be maintained.

Each set interval may be 20 second or substantially 20 seconds. Alternatively, each set internal may be, or may be substantially, s seconds, 10 seconds, 30 seconds. 40 seconds, 50 seconds, or 60 seconds.

After each set interval, the controller may be configured to reset the key fob signal if the detection signal is no longer provided by the detector. Thus, moving the key fob away from the target will result in the key fob resuming normal working operation.

By reset, it is meant that the key fob signal may be re-enabled if suppressed or may be returned to its former state if modified.

The target may be passive, i.e. may be unpowered. A power supply for the target will therefore not be required, and the only power required by the system may be that provided by the key fob.

According to a second aspect, there is provided a key fob comprising: a transmitter configured to transmit a key fob signal; and a detector configured to provide a detection signal to a controller when a target is within a detectable range; wherein wherein the controller is configured to cause suppression or modification of the key fob signal when the detection signal is provided by the detector.

The detectable rage of the target may be 100 mm or less, or may be 40 mm or less.

By providing a detectable range that is relatively small, it can be ensured that the key fob signal is only modified or suppressed when it is in close proximity to the target.

The target may comprise an NFC tag that is detectable by the detector. Use of a tag allows the adaptation of an object of the choice of the user into a target for use in the present system. The NFC tag may be an NFC sticker, i.e. an adhesive tag with an embedded or surface-mounted NFC device.

The target may be a key tray or other receptacle.

The key fob signal before modification or suppression may be an unlock signal. Receipt of the unlock signal at the vehicle will therefore result in unlocking of the vehicle.

Each set interval may be 20 second or substantially 20 seconds. Alternatively, each set internal may be, or may be substantially, 5 seconds, 10 seconds, 30 seconds, 40 seconds, 50 seconds, or 60 seconds.

According to a third aspect, there is provided a method of suppressing or modifying a key fob signal, comprising: providing a detection signal to a controller when a target is within a detectable 20 range and suppressing or modifying a key fob signal transmitted by a key fob when the detection signal is provided.

The target may be detected using NFC.

The key fob may be configured for use with a vehicle, the modifying of the key fob signal including enabling or disabling one or more functions of the vehicle.

The one or more functions may include complete unlock, partial unlock, or start-up of the vehicle.

Modifying the key fob signal may include altering a message conveyed by the key fob signal.

Suppressing the key fob signal may include not transmitting the key fob signal.

The method may further comprise polling for the target at set intervals, the suppressing or modifying of the key fob signal being constant between the set intervals.

The method may further comprise resetting the key fob signal if the detection signal is no longer provided.

The target may be passive, i.e. may be unpowered.

The method may include any of the features of the first or second aspects.

According to a fourth aspect, there is provided a key fob signal modification system, comprising: a key fob including a transmitter configured to transmit a key fob signal and a target configured such that, when the key fob is in a detectable range of the target, the key fob signal is modified.

Modifying the key fob signal can change the message conveyed by the key fob such that it has a different effect on the device on which it acts.

The system may further comprise a controller that causes a modification of the key fob signal when the key fob is in the detectable range of the target.

The key fob may comprise the controfler. the controller instructing the transmitter to modify the key fob signal The key fob may comprise a target detector configured to detect the target, the target detector being configured to instruct the controller to modify the key fob signal when the target is detected.

The key fob may therefore be a self-contained unit including the necessary circuitry to provide the modification within itself.

The target may comprise a tag.

The tag may include a sticker.

The tag may include an NFC tag.

Use of a tag allows the adaptation of an object of the choice of the user into a target for use in the present system. The NFC tag may be an NFC sticker, i.e. an adhesive tag with an embedded or surface-mounted NFC device The target may comprise the controller, the controller being configured to communicate with the key fob to cause the transmitter to modify the key fob signal.

The target may further comprise a key fob detector configured to detect the key fob, the key fob detector being configured to instruct the controller to modify the key fob signal when the key fob is detected.

By providing the controller and/or key fob detector within the target, the key fob may be prevented from requiring similar circuitry within itself, which may allow it to be smaller and/or more compact.

The key fob detector may be configured to detect a tag associated with the key fob.

The tag may include a key ring or sticker. The tag may therefore be arranged to be attached to the key fob without necessarily being internal to the key fob.

The tag may include an NFC tag.

According to a fifth aspect, there is provided a method of modifying a key fob signal, corn p ri sing: modifying a key fob signal transmitted by a key fob when the key fob is in a detectable range of a target.

The modifying of the key fob may be caused by a controller.

The key fob may comprise the controller, the controller instructing a transmitter to modify the key fob signal.

The target may comprise the controller, the controller communicating with the key fob to cause a transmitter to modify the key fob signal.

The method may further comprise detecting the key fob with a key fob detector, the key fob detector instructing the controller to modify the key fob signal when the key fob is detected.

The method may further comprise detecting a tag associated with the key fob.

The tag may include a key ring or sticker.

The tag may include an NFC tag.

The method may further comprise any of the features of the fourth aspect.

The present invention will now be described in detail with reference to the accompanying drawings, in which: Figure 1 is a schematic view of a key fob and vehicle; Figure 2 is a schematic view of the key fob and vehicle of Figure 1, with the key fob in the vicinity of a key tray; Figure 3 is a schematic view of the key fob and key tray of Figure 2; Figure 4 is a flow chart of a method of modifying or suppressing a key fob signal; and Figure 5 is a schematic view of a second embodiment of a key fob and key tray.

Referring firstly to Figure 1, there is shown a key fob 102 and a vehicle 104. As is commonplace in the art, the key fob 102 communicates with the vehicle 104 in order to provide an unlock signal to the vehicle 104. This signal may be provided in many ways, of which the skilled person will be knowledgeable. In the present case, the signal is provided as a two-way communication between the key fob 102 and the vehicle 104. The vehicle 104 is configured to emit a first signal which initiates a response, hereinafter referred to as a key fob signal 106, from the key fob 102 when the key fob 102 is within range. The key fob signal 106 initiates the unlocking of the vehicle 104 and allows the vehicle 104 to be started up using a start/stop button on the dashboard of the vehicle 104. Whilst this is the standard method of communication, other methods of operation are also applicable to the presently described invention and the invention is therefore not intended to be limited to the described method.

In Figure 2, the key fob 102 has been placed on a target 108, which in the present embodiment is a key tray. The target 108 may take the form of any object and the key fob 102 may be placed on or near to the target 108, as preferred. The target 108 may therefore be a key tray, a mat, a box, or any other object. The key fob 102 and target 108 may be considered to be a key fob signal suppression or modification system 100.

When the key fob 102 and target 104 are within a predetermined distance of each other, the key fob 102 is caused to suppress or modify the key fob signal 106. The modified key fob signal 106a is shown in Figure 2. In the depicted embodiment, the key fob 102 and target 108 communicate in order to cause the suppression or modification of the key fob signal 106. Although termed "communication", in the embodiment of Figures 1 to 3 the key fob 102 acts to detect the target 108 without the target 108 being powered.

The suppression or modification of the key fob signal 106 may take any one of a number of different forms. In one example, the presence of the target 108 may cause the key fob 102 to cease sending any key fob signal 106 at all, i.e. the key fob signal 106 may be suppressed. in other examples, the key fob signal 106 may be modified such that its message is interpreted differently or not detected at all by the vehicle 104. Any form of modification may be used and will be well known to the person skilled in the art, including a change in the content of the message conveyed by the key fob signal 106 or a change in the frequency or modulation pattern of the key fob signal 106.

In sonic embodiments, the modification of the key fob signal 106 may change the content of the message conveyed by the key fob signal 106 such that it has a different effect on the vehicle 104. For example, the key fob signal 106 emitted with the key fob 102 close to the target 108, i.e. within the detectable range, may still cause the vehicle 104 to be unlocked but may not allow the vehicle 104 to be started. As such, theft of the vehicle 104 will be prevented. Alternatively, the key fob signal 106 may allow one door to be opened, such as the boot or trunk, whilst simultaneously preventing the opening of other doors, such as the passenger doors. Other options for modification of the key fob signal 106 may also be provided, depending on the specific requirements of the user.

The specific workings of the key fob 102 and target 108 are shown in Figure 3. The key fob 102 includes a detector 110, a controller 112, and a transceiver 114. The transceiver 114 is used to emit the key fob signal 106 and also to receive transmissions from the vehicle 104, due to the two-way communication required to unlock the vehicle 104 in the present embodiment.

The controller 112 operates the transceiver 114 in order to control the key fob signal 106 output by the transceiver 114. In order to do so, the controller 112 receives a signal from the detector 110 as to whether or not the target 108 is within a detectable range of the detector 110. Although described as a -detectable range", the signal may indicate either that the target 108 is not detected or. where the detector 110 is capable of detecting a distance 110 between the detector 110 and the target 108, where the target is further than a predetermined distance away from the detector 110.

In the present embodiment, the target 108 includes an NFC tag 116, which is detectable by the detector 110. When the NFC tag 116 is within the detectable range of the detector 110, for example when the key fob 102 is placed on or in the immediate vicinity of the target 108, the detector 110 will detect the NFC tag 116 and will output a detection signal to the controller 112. in turn, the controller 112 will effect a modification or suppression of the key fob signal 106 emitted by the transceiver I 14.

In the present embodiment, the NFC tag 116 and detector 110 provide a short detectable range that is considered to be advantageous as the key fob 102 must be placed close to or on the target 108 in order to cause suppression or modification of the key fob signal 106. This ensures that the presence of the target 108, for example close to the front door of a house or other dwelling, does not hinder the operation of the key fob 102 when desired to be used to unlock a vehicle 104 parked close to the house. The NFC communication may provide a detectable range of 100 mm or less or preferably a detectable range of 40 mm or less. However, where desired, the key fob 102 and target 108 may be configured to provide any desired detectable range.

Whilst the detector 110 of the key fob 102 may continuously search for the target 108, it may be desirable to limit the power usage of the detector 110. As the key fob 102 is powered by a battery 118, operating the detector 110 such that it only attempts to detect, or polls for, the target 108 at predefined intervals will save power and allow the key fob 102 to have a longer battery life. In the present embodiment, the detector is configured to poll for the target every 20 seconds, but any suitable interval may be provided. The polling interval may be selected to provide an acceptable compromise between prolongation of the battery life of the key fob 102 and ensuring that the detector 110 updates the controller 112 as to whether or not the key fob 102 is in the vicinity of the target 108 at frequent enough intervals that the key fob 102 is not prevented from unlocking the vehicle 104 at a time at which the user wants to unlock the vehicle 104.

In some embodiments, it may be desirable to alter the polling interval based on a sensor input to the key fob. For example, an accelerometer may be included within the controller that senses movement of the key fob, such as when a user picks the key fob off a surface, and increases the frequency of the polling. Other sensors or inputs could also be used that alter the frequency of the polling interval.

The controller 112 controls the transceiver 114 such that between polling intervals of the detector 110, the key fob signal 106 emitted by the transceiver 114 is maintained. For example, if the detector 110 determines at a first polling time that the target 108 is not within the detectable range of the detector 110, then the transceiver 114 will continue to emit the key fob signal 106 without suppression or modification. If the target 108 is detected, the controller 112 will cause the transceiver 114 to emit a modified or suppressed key fob signal 106a. as necessary, until such a time as the detector 110 polls for the target 108 and fails to detect it.

A flow chart showing each step of the operation of the system 100 as thus far described is shown in Figure 4.

Though the system 100 thus far has been described as being for the suppression or modification of the key fob signal 106, systems may be provided that either modify or suppress the key fob signal or systems may be provided that modify the key fob signal in one situation and suppress the signal in another. For example, multiple targets 108 may be provided, such that the detector 110 provides a different detection signal based on which target 108 is detected. A first target 108 may completely suppress the key fob signal 106 whilst a second target 108 may modify the signal 106. Any number of different targets 108 may be provided, and the user may place the key fob 102 next to or on each target 108 depending on their particular requirements at any given time.

A second embodiment of a system 200 including a key fob 202 and target 208 is shown in Figure 5, in the second embodiment, the target 208 is active rather than passive, i.e. it includes its own power supply, here in the form of a battery 220, although alternative power supplies could also be used, such as a mains power supply, solar panel, or alternative The system of Figure 5 can therefore have a different arrangement, as shown in Figure 5, the target 208, which again is in the form of a key tray or mat, although it may take any other form, includes the detector 210. The detector 210 is configured to detect the key fob 202. The key fob 202 therefore includes an NFC tag 216, which can be detected by the detector 210 of the target 208. Contrastingly from the first embodiment, in the present embodiment, the controller 212 is also housed within the target 208 and receives the detection signal from the detector 210. In response, the controller 212 communicates with a receiver 222 of the key fob 202 in order to cause modification or suppression of the key fob signal 206 transmitted by the transceiver 214. The key fob is includes a battery 218. The remainder of the operation of the system 200 of the second embodiment is the same as the operation of the system 100 of the first embodiment, except where necessary due to difference in position of some of the features. By providing the detector 210 and controller 212 in the target 208, the key fob 202 may be prevented from including any unnecessary parts that could add complexity or size.

While in this embodiment the controller 212 of the target 208 communicates with a receiver 222 of the key fob 202, the receiver 222 may provide additional processing of and therefore be termed a secondary controller.

Claims

CLAIMSA key fob signal suppression or modification system, comprising: a key fob including a transmitter, a detector, and a controller, the transmitter being configured to transmit a key fob signal and the detector being configured to provide a detection signal to the controller when a target is within a detectable range; and wherein the controller is configured to cause suppression or modification of the key fob signal when the detection signal is provided by the detector.
2. A key fob signal suppression or modification system according to claim 1, wherein the detectable range of the target is 100 mm or less or 40 mm or less.
A key fob signal suppression or modification system according to claim 1 or claim 2, wherein communication between the key fob and the target is via NFC, optionally wherein the target comprises an NFC tag that is detectable by the detector, for example an NFC sticker.
4 A key fob signal suppression or modification system according to any preceding claim, wherein, when the key fob is configured for use with a vehicle, the key fob signal being modifiable to enable or disable one or more functions of the vehicle, optionally wherein the one or more functions include complete unlock, partial unlock, or start-up of the vehicle.
5 A key fob signal suppression or modification system according to any preceding claim, wherein modification of the key fob signal includes alteration of a message conveyed by the key fob signal and/or wherein suppression of the key fob signal includes the key fob signal not being transmitted
6. A key fob signal suppression or modification system according to any preceding claim, wherein the key fob signal before modification or suppression is an unlock signal.
7. A key fob signal suppression or modification system according to any preceding claim, wherein the detector is configured to poll for the target at set intervals, the suppression or modification of the key fob signal being constant between the set intervals, optionally wherein each set inten;a1 is 20 seconds or substantially 20 seconds.
8. A key fob signal suppression or modification system according to claim 7, wherein, after each set interval, the controller is configured to reset the key fob signal if the detection signal is no longer provided by the detector.
9. A key fob signal suppression or modification system according to any preceding claim, wherein the target is passive.
10. A key fob comprising: a transmitter, a detector, and a controller, wherein: the transmitter is configured to transmit a key fob signal; the detector is configured to provide a detection signal to the controller when a target is within a detectable range; and the controller is configured to cause suppression or modification of the key fob signal when the detection signal is provided by the detector.
11. A method of suppressing or modifying a key fob signal, comprising: providing a detection signal to a controller when a target is within a detectable range and suppressing or modifying a key fob signal transmitted by a key fob when the detection signal is provided.
12. A method according to claim 11, wherein the target is detected using NEC.
13. A method according to claim 11 or claim 12, wherein the key fob is configured for use with a vehicle, the modifying of the key fob signal including enabling or disabling one or more functions of the vehicle, optionally wherein the one or more functions include complete unlock, partial unlock, or start-up of the vehicle.
14. A method according to any of claims 11 to 13, wherein modifying the key fob signal includes altering a message conveyed by the key fob signal and/or wherein suppressing the key fob signal includes not transmitting the key fob signal.
15. A method according to any of claims 11 to 14, further comprising polling for the target at set intervals, the suppressing or modifying of the key fob signal being constant between the set intervals, optionally wherein each set interval is 20 seconds or substantially 20 seconds.
16. A method according to claim 15, further comprising resetting the key fob signal if the detection signal is no longer provided.
17. A method according to any of claims 11 to 16, wherein the target is passive.
18. A key fob signal modification system, comprising: a key fob including a transmitter configured to transmit a key fob signal; and a target configured such that, when the key fob is in a detectable range of the target, the key fob signal is modified.
19. A key fob signal modification system according to claim 18, further comprising a controller that causes a modification of the key fob signal when the key fob is in the detectable range of the target.
20. A key fob signal modification system according to claim 18 or claim 19, wherein the key fob comprises the controller, the controller instructing the transmitter to modify the key fob signal.
21. A key fob signal modification system according to claim 20, wherein the key fob comprises a target detector configured to detect the target, the target detector being configured to instruct the controller to modify the key fob signal when the target is detected, optionally wherein the target comprises a tag, which may include a sticker and/or an NFC tag.
22. A key fob signal modification system according to claim 18 or claim 19, wherein the target comprises the controller, the controller being configured to communicate with the key fob to cause the transmitter to modify the key fob signal.
23. A key fob signal modification system according to claim 22, wherein the target further comprises a key fob detector configured to detect the key fob, the key fob detector being configured to instruct the controller to modify the key fob signal when the key fob is detected, optionally wherein the key fob detector is configured to detect a tag associated with the key fob, which may include a key ring or sticker and/or may include an NFC tag.
24. A method of modifying a key fob signal, comprising: modifying a key fob signal transmitted by a key fob when the key fob is in a detectable range of a target.
25. A method according to claim 24, wherein the modifying of the key fob signal is caused by a controller.
26. A method according to claim 25, wherein the key fob comprises the controller, the controller instructing a transmitter to modify the key fob signal.
27. A method according to claim 25, wherein the target comprises the controller, the controller communicating with the key fob to cause a transmitter to modify the key fob signal.
28. A method according to any of claims 24 to 27, further comprising detecting the key fob with a key fob detector, the key fob detector instructing the controller to modify the key fob signal when the key fob is detected.
29. A method according to any of claims 24 to 28, further comprising detecting a tag associated with the key fob, which may include a key ring or sticker, and/or may include an NFC tag.