SYSTEM COMPRISING A DOOR, A DOOR LOCK AND A RADIO KEY

Abstract

The invention relates to a system comprising a door, in particular of a vehicle, having a door lock, a door control module that has a transmission/reception unit at the door side or is connected thereto, and having a key that is associated with the door lock and that has a transmission/reception unit at the key side, wherein the transmission/reception unit at the door side and the transmission/reception unit at the key side are configured for radio communication. The time of flight of a radio signal transmitted by the transmission/reception unit at the door side and reflected by the transmission/reception unit at the key side can be determined by means of the transmission/reception unit at the door side. Alternatively, the time of flight of a radio signal transmitted by the transmission/reception unit at the key side and reflected by the transmission/reception unit at the door side can be determined by means of the transmission/reception unit at the key side.

Claims

1.-15. (canceled)

16. A system comprising a door having a door lock; a door control module that has or is connected to a transmission/reception unit at the door side; and a key that is associated with the door lock and that has a transmission/reception unit at the key side, wherein the transmission/reception unit at the door side and the transmission/reception unit at the key side are configured for radio communication, wherein the time of flight of a radio signal transmitted by the transmission/reception unit at the door side and reflected by the transmission/reception unit at the key side can be determined by the transmission/reception unit at the door side; or wherein the time of flight of a radio signal transmitted by the transmission/reception unit at the key side and reflected by the transmission/reception unit at the door side can be determined by the transmission/reception unit at the key side.

17. The system in accordance with claim 16, wherein the door is a vehicle door.

18. The system in accordance with claim 16, wherein the transmission/reception unit determining the time of flight of a reflected radio signal activates a comfort function when the time of flight of the reflected radio signal falls below a predefined first threshold value or when the time of flight of the reflected radio signal exceeds a predefined second threshold value.

19. The system in accordance with claim 18, wherein the activation of the comfort function comprises at least one function selected from the group of members consisting of the door being automatically opened or automatically closed and locked; a vehicle top being automatically opened or closed; a retracted door handle being traveled out or traveled in; a signal generator being switched on for position determination; an acoustic and/or visual signal generator being switched on for position determination; at least one light being switched on for position determination; a welcome lighting being switched on; a window regulator being actuated; a ventilation being switched on; a seat heating being switched on; an independent vehicle heater being switched on; and combinations of the foregoing.

20. The system in accordance with claim 18, wherein the first threshold value and the second threshold value are the same.

21. The system in accordance with claim 18, wherein different threshold values are provided for different comfort functions.

22. The system in accordance with claim 18, wherein threshold valve each threshold value can be individually set by a user at the door side and/or at the key side.

23. The system in accordance with claim 18, wherein a comfort function is only actuable during a predefined time window.

24. The system in accordance with claim 16, wherein the transmission/reception unit determining the time of flight of a reflected radio signal only transmits radio signals during a predefined time window.

25. The system in accordance with claim 24, wherein the time window at the door side and/or at the key side can be individually set by a user.

26. The system in accordance with claim 16, wherein the transmission/reception unit determining the time of flight of a reflected radio signal transmits radio signals repeatedly and detects whether they are reflected by a transmission/reception unit at the key side.

27. The system in accordance with claim 26, wherein the transmission/reception unit transmits radio signals repeatedly at regular time intervals.

28. The system in accordance with claim 16, wherein the reflecting transmission/reception unit always automatically reflects a radio signal received from the transmission/reception unit determining the time of flight of a reflected radio signal back to it.

29. The system in accordance with claim 16, wherein the reflecting transmission/reception unit only reflects a radio signal received from the transmission/reception unit determining the time of flight of a reflected radio signal back to it when a user has previously carried out a predefined release action.

30. The system in accordance with claim 16, wherein the radio signal transmitted by the transmission/reception unit determining the time of flight of a reflected radio signal is an encrypted digital signal.

31. The system in accordance with claim 16, wherein the reflecting transmission/reception unit modifies a radio signal received from the transmission/reception unit determining the time of flight of a reflected radio signal before transmitting it back to it.

32. The system in accordance with claim 31, wherein the reflecting transmission/reception unit modifies the radio signal received from the transmission/reception unit determining the time of flight of a reflected radio signal by providing it with an authentication code.

33. The system in accordance with claim 16, wherein the transmission/reception unit at the door side initiates an automatic closing of the door and/or a locking of the door lock if it does not receive any reflected radio signal.

Description

[0027] The invention will be described in the following purely by way of example with reference to a possible embodiment and to the enclosed drawing. There are shown:

[0028] FIG. 1 a vehicle and a radio key that is associated with the vehicle and that is located outside the range of a radio connection between the vehicle and the radio key;

[0029] FIG. 2 the vehicle and the radio key of FIG. 1, with the radio key being located within the range of the radio connection between the vehicle and the radio key, but still at a large distance from the vehicle;

[0030] FIG. 3 the vehicle and the radio key of FIG. 1, with the radio key being located within the range of the radio connection between the vehicle and the radio key, but at an intermediate distance from the vehicle; and

[0031] FIG. 4 the vehicle and the radio key of FIG. 1, with the radio key being located within the range of the radio connection between the vehicle and the radio key at such a small distance from the vehicle that a tailgate of the vehicle is automatically opened.

[0032] A vehicle 10 is shown in the Figures with which a radio key 12 is associated which can communicate in a manner known per se by means of radio with a door control module, here in the form of a central locking, of the vehicle 10. The radio key 12 has a first button 14 on whose actuation the radio key 12 transmits an unlocking signal to the central locking of the vehicle 10 and a second button 16 on whose actuation the radio key 12 transmits a locking signal to the central locking of the vehicle 10.

[0033] In addition, the radio key 12 has a third key 18 on whose single actuation the radio key 12 transmits a signal to the central locking that effects an unlocking and opening only of a tailgate 20 of the vehicle 10 provided that the radio key 12 is located within the range of the radio connection between the vehicle 10 and the radio key 12. A multiple actuation, for example a threefold actuation, of the third button 18 in contrast actuates a transmission/reception unit of the radio key 12, i.e. a transmission/reception unit at the key side, and indeed even if the radio key 12 is outside the range of the radio connection.

[0034] The vehicle 10 comprises a corresponding transmission/reception unit at the vehicle side, also called a transmission/reception unit at the door side in this context, that is integrated into the central locking in the present embodiment, but can generally also be formed separately therefrom. The transmission/reception unit at the door side is connected either indirectly via the central locking or directly to a drive, for example an electric motor drive, for unlocking and opening the tailgate 20.

[0035] The transmission/reception unit at the vehicle side has a plurality of antennas arranged at different points of the vehicle 10 and transmits radio signal 22 via then into the environment of the vehicle 10 at regular time intervals. These radio signals 22 are encrypted digital signals.

[0036] The radio signals 22 transmitted by the transmission/reception unit at the vehicle side are received by the activated transmission/reception unit at the key side as soon as the radio key 12 is within the range of the radio connection between the vehicle 10 and the radio key 12. The received radio signals 22 are provided with an authentication code by the transmission/reception unit at the key side and are sent back to the transmission/reception unit at the vehicle side as reflected radio signals 24. The radio signals 22 transmitted by the transmission/reception unit at the vehicle side are therefore so-to-say reflected back from the radio key 12.

[0037] The authentication codes of the reflected radio signals 24 are checked in the transmission/reception unit at the vehicle side. In addition, the times of flight of the reflected radio signals 24 are determined, i.e. the times are therefore measured that elapse from the irradiation of the radio signals 22 up to the reception of the corresponding reflected radio signals 24. The transmission/reception unit at the vehicle side is provided with or connected to a suitable measurement module for this purpose. Since the radio signals 22, 24 generally propagate at the speed of light, the distance between the transmission/reception unit at the vehicle side and the transmission/reception unit at the key side can be calculated from the time of flight of a radio signal 22, 24, i.e. a conclusion can therefore be drawn on the distance of the radio key 12 from the vehicle 10.

[0038] If the radio key 12 approaches the vehicle 10, the times of flight of the reflected radio signals 24 decrease. As soon as the time of flight of a reflected radio signal 24 falls below a predefined first threshold value, i.e. the radio key 12 therefore falls below a predefined distance from the vehicle 10, and as soon as the authentication of the reflected radio signal 24 is positive, the transmission/reception unit at the vehicle side activates the drive of the tailgate 20 to automatically unlock and open it.

[0039] If the radio key 12 subsequently again moves away from the vehicle 10, the times of flight of the reflected radio signals 24 increase again. As soon as the time of flight of a reflected radio signal 24 exceeds a predefined second threshold value, i.e. the radio key 12 therefore exceeds a predefined distance from the vehicle 10, the transmission/reception unit at the vehicle side controls the drive of the tailgate 20 such that it is again closed and locked.

[0040] The first threshold value and the second threshold value can generally be selected as the same. In practice, it has, however, proven advantageous if the automatic opening of the tailgate 20 is already initiated when a user carrying the radio key 12 with him has already approached the vehicle 10 up to 3 m, for example, whereas the automatic closing of the tailgate 20 can be started when the radio key 12 has reached a distance of 1.5 m from the tailgate 20.

[0041] The threshold values at which the automatic opening and closing of the tailgate 20 is triggered can ideally be individually set by a user, for example by means of a touchscreen which is provided in the vehicle 10 and via which the corresponding parameters can be input into the central locking and thus ultimately into the transmission/reception unit at the vehicle side.

REFERENCE NUMERAL LIST

[0042] 10 vehicle

[0043] 12 radio key

[0044] 14 first button

[0045] 16 second button

[0046] 18 third button

[0047] 20 tailgate

[0048] 22 transmitted radio signal

[0049] 24 reflected radio signal