DE102011050160A1 - Identification transmitter i.e. check card, for use in locking system of motor car to identify authorized person to unlock car, has receiving unit switched-off when motion sensor senses immobility of transmitter during minimum time duration - Google Patents

Abstract

The transmitter (1) has a receiving unit (10) for receiving a transmitting signal, which is sent from a transmission receiving module to a vehicle. A microcontroller (11) controls the receiving unit. An energy storage unit (12) i.e. button cell battery, provides power supply to the receiving unit and the microcontroller. A motion sensor (13) senses a movement of the transmitter. The receiving unit is switched-off by the microcontroller when the motion sensor senses an immobility of the transmitter during minimum time duration. An independent claim is also included for a method for operating a locking system of a vehicle using an identification transmitter.

Description

The present invention relates to an identification transmitter of a locking system of a vehicle, designed to identify an authorized person to unlock the vehicle and / or start. The identification transmitter comprises a receiving unit which is designed to receive a transmission signal which can be emitted by a transceiver module in the vehicle, wherein a microcontroller is provided for controlling the receiving unit, wherein the identification transmitter further comprises an energy store for supplying power to at least the receiving unit and the microcontroller , Furthermore, a motion sensor is provided in the identification transmitter, which is designed to sense a movement of the identification transmitter, according to the preamble of claim 1.

STATE OF THE ART

From the DE 199 27 253 C2 an identification transmitter of a locking system of a vehicle is known, which has a motion sensor to sense a movement of the identification transmitter. If the identification transmitter is not moved over a predetermined period of time, communication with the transceiver module in the vehicle is disabled. This ensures that an authorization check for unlocking the locking system of the vehicle and / or for starting the vehicle can only take place if the identification transmitter has been moved within a certain time interval before the authorization check. The transmission of an identity code can only be released upon fulfillment of this criterion. Thus, in the authorization check, whether a person is allowed to unlock and / or start the vehicle is examined as an additional criterion as to whether the identification transmitter has been moved within a time interval of, for example, 10 seconds to 30 seconds before the authorization check. In this case, the fact is used that an authorized person has usually gone immediately before carrying out the authorization check to the vehicle or immediately before sitting on the vehicle seat, so that the user-carried identification transmitter movements, accelerations or shocks was exposed. So that so-called relay station attack attacks can be counteracted, in which the presence of the identification transmitter is simulated in the vicinity of the vehicle with the aid of technical means, and so that the vehicle can be unlocked without the knowledge of the authorized person by an unauthorized person or even started. If such an unauthorized remote inquiry is attempted, then the probability is quite high that the identification transmitter has not been moved immediately prior to the authorization request, for example if it has been filed in the living space of the authorized person.

Such mobile identification transmitter have a power supply in the form of a battery, which is preferably designed as a button cell. In order for the identification transmitter to emit an authentication signal to the transceiver module in the vehicle, the identification transmitter must first receive an LF signal (for example, 125 kHz), which is transmitted by the transceiver module in the vehicle. The field strength with which the transceiver module transmits the LF signal is designed so weak that the reception by the identification transmitter can only take place in the vicinity of the vehicle. If the LF signal is received by the receiving unit in the identification transmitter, the signal is analyzed by the microcontroller and by an RF module in the identification transmitter, the authentication signal is sent back from the identification transmitter to the transceiver module in the vehicle. Only upon receipt of the authentication signal from the identification transmitter is the proof of the authorization of a person to unlock the vehicle and / or start.

In order to create a permanent readiness to receive the identification transmitter, in particular the receiving unit in the identification transmitter, a quiescent current is required, with which the energy store feeds the receiving unit and / or the microcontroller. This quiescent current flows permanently, so that the life of the energy storage, for example, the button cell in the identification transmitter, is limited.

Frequently, the vehicle manufacturer requires lifetimes for the energy store in the identification transmitter, which can not be achieved due to the required supply with a quiescent current.

It is therefore the object of the present invention to provide an identification transmitter of a locking system of a vehicle, which overcomes the disadvantages of the prior art referred to above, and in particular the object of the present invention to provide an identification transmitter with a reduced power consumption.

This object is achieved on the basis of an identification transmitter for a vehicle according to the preamble of claim 1 in conjunction with the characterizing features. Advantageous developments of the invention are specified in the dependent claims.

The invention includes the technical teaching that at least the receiving unit can be switched off by the microcontroller when the motion sensor senses a motionlessness of the identification transmitter during a minimum period of time.

The invention is based on the idea of at least reducing the power requirement from the energy store by switching off the receiving unit by the microcontroller. If the identification transmitter has not been moved for a long time, then it can be assumed that it has been discarded, thus obviating the need for the vehicle to be unlocked and / or started by the authorized person without first having at least briefly moved the identification transmitter , The power consumption can be reduced so much that only the motion sensor remains activated. The main part of the energy demand in the idle state of the identification transmitter is justified by the receiving unit, and when this is turned off, accounts for a large part of the energy demand. During operation of a vehicle, over the useful life of the vehicle there is a considerable proportion of rest periods over which the vehicle is parked and over which the identification transmitter is also not in use. This non-use is sensed by the motion sensor, and thus the power supply of the receiving unit is resumed only when the microcontroller in conjunction with the motion sensor senses the use of the identification transmitter. The identification transmitter can be integrated, for example, in the key of the vehicle. The inventive shutdown of the receiving unit by the microcontroller, when the motion sensor senses a motionlessness of the identification transmitter during a minimum period of time, leads to the advantage that the energy storage has a significantly extended life. The often as a battery, especially as a button cell, running energy storage can supply up to 5 years or more the identification transmitter with electricity, whereby a significant extension of the life of the energy storage is achieved, as in identification encoders in which the receiving unit is permanently on standby.

Advantageously, the shutdown of the receiving unit may comprise at least one non-functional setting of the receiving unit, in particular that the shutdown leads to a reduction of the current consumption of the identification transmitter to a maximum of 2 uA, in particular to a maximum of 0.4 uA. Due to the inoperative setting of the receiving unit, the solution according to the invention simultaneously achieves the advantage that relay station attack attacks are no longer possible, so that the motion sensor in the identification transmitter leads both to the advantage of reducing the power consumption in the identification transmitter, and further to that Advantage leads to be able to ward off relay station Attack attacks, since the receiving unit with stored identification transmitter, which was not moved for a minimum period of time, does not respond to an LF signal of the transceiver module in the vehicle. This leaves the reaction of the identification transmitter to the LF signal, which is given for example by a relay station module on the identification transmitter. If the current consumption is only 0.4 μA, so that a state of the identification transmitter can be described, which is energized only the motion sensor as a means for monitoring a movement of the identification transmitter. If the current consumption of the identification transmitter is still 6μA when the receiver unit is activated, the current consumption can be reduced by a factor of 15 with a maximum current consumption of 0.4 μA.

With further advantage, the identification transmitter can comprise an HF module for communication with the transceiver module in the vehicle, the communication comprising a query as to whether the identification transmitter is located inside or outside the vehicle. In the vehicle LF antennas may be present, which can communicate with the receiving unit of the identification transmitter. Thus, the information can be transmitted to the identification transmitter, whether this is inside or outside the vehicle.

If the identification transmitter is in the vehicle, the minimum period of time for switching off the receiver unit by the microcontroller can be at least 30 minutes, preferably at least 1 hour and more preferably at least 2 hours. If the identification transmitter is located outside the vehicle, the minimum time duration for switching off the receiver unit by the microcontroller can be at most 10 minutes, preferably at most 5 minutes and particularly preferably at most 2 minutes. The identification transmitter can be stored in the vehicle, for example in the jacket of the authorized person. If the authorized person wants to start the vehicle by the authorized person, for example, presses the start button to start the engine, there is a communication of the in-vehicle identification transmitter with the transceiver module in the vehicle instead. It can be assumed that the vehicle is already unlocked, and even over a longer period, for example, up to 2 hours, was already unlocked. If the authorized person now actuates the start button for starting the engine of the vehicle, the identification transmitter can be interrogated by the transceiver module in the vehicle even after a relatively long time. Has the minimum time period been exceeded, within If the identification transmitter is located in the vehicle, the authorized person can be requested via a display means in the vehicle to move the identification transmitter so that the receiving unit in the identification transmitter is reactivated by the motion sensor in conjunction with the microcontroller.

If the identification transmitter is located outside the vehicle, then it is to be assumed that when the motion sensor no longer senses any movement of the identification transmitter over a minimum period of time, it has been stored. To increase security against a relay station attack attack and to better reduce the power consumption of the ID transmitter, the minimum period of time may be reduced to, for example, 2 minutes when the ID transmitter is outside the vehicle.

In particular, the information as to whether the identification transmitter is located inside or outside the vehicle can be stored in the identification transmitter. Furthermore, the information can be transmitted to the identification transmitter at each opening and closing of a flap of the vehicle, whether it is inside or outside the vehicle.

With further advantage, the receiving unit for the periodic query of the reception of the transmission signal from the transceiver module can be formed in the vehicle. The method, also referred to as "pollen or polling", leads to a further reduction in the power consumption of the identification transmitter. If the identification transmitter in the vehicle has not been moved for a long time, the request can be made via the display means to move the key once.

According to a further advantageous measure of the present invention, the microcontroller of the identification transmitter can be designed for the diagnosis of the motion sensor, such that a defect of the motion sensor can be diagnosed by means of the microcontroller. The diagnosis can be made, for example, such that when a switching means present on the identification transmitter is manually actuated by the authorized person, the motion sensor must also sense a movement of the identification transmitter. If there is no sensing of the movement of the identification transmitter during the manual actuation of the switching means, then the defect of the motion sensor can be assumed. If the motion sensor is defective, the receiving unit can be kept in permanent readiness. For example, an information signal can be transmitted to the transceiver module in the vehicle, so that the defect of the motion sensor can be read out via a corresponding interface in the vehicle by a specialist workshop.

Advantageously, the microcontroller can be designed such that it can be brought into an intermediate state in which the supply current of the microcontroller through the energy store is less than 1 μA, in particular less than 0.4 μA. In this switching state, the motion sensor and the manually operable switching means can be active on the identification transmitter, the receiving unit and a timer present in the microcontroller and the microcontroller itself being switched off. In this state, the current consumption from the energy store can be, for example, 0.4 μA. In particular, the microcontroller can be brought into a further intermediate state in which the motion sensor, the manually operable switching means and a timer present in the microcontroller are actively switched, and the receiving unit and the microcontroller itself are switched off. In this intermediate state, the supply current provided by the energy store can be, for example, 2 μA.

The object of the present invention is further achieved by a method for operating a locking system for a vehicle having an identification transmitter for identifying an authorized person to unlock the vehicle and / or start, with a receiving unit for receiving a transmission signal from a transceiver module in Vehicle, a microcontroller for controlling the receiving unit, an energy storage device for powering at least the receiving unit and the microcontroller, a motion sensor by which a movement of the identification transmitter is sensed, wherein the method at least provides that determines a period of time by the microcontroller in conjunction with the motion sensor is whether the identification transmitter is immobile over the period of time, wherein a further comparison of the duration of immobility with a minimum period of time takes place and a shutdown of the receiving unit by the microcontroller is then provided if dur ch the motion sensor is sensed on reaching the minimum period of immobility of the identification transmitter.

According to an advantageous development of the method can be queried by the identification transmitter by means of a communication with the transceiver module in the vehicle, whether the identification transmitter is inside or outside the vehicle. If the identification transmitter is located in the vehicle, the minimum period of time for switching off the receiver unit by the microcontroller can be at least 30 minutes, preferably at least 1 hour and more preferably at least 2 hours. Is the Identification transmitter outside the vehicle, the minimum period of time for switching off the receiving unit by the microcontroller can be at most 10 minutes, preferably at most 5 minutes and more preferably at most 2 minutes.

With further advantage, the vehicle may have a display means by which the authorized person may be requested to move the identification transmitter, in particular if the identification transmitter is in the vehicle and has not been moved over the minimum period of time and in particular the intention is signaled by the authorized person, to start the vehicle.

PREFERRED EMBODIMENT FOR CARRYING OUT THE INVENTION

Further, measures improving the invention will be described in more detail below together with the description of a preferred embodiment of the invention with reference to FIGS. Show it:

1 a schematic view of an identification transmitter with the features of the present invention and

2 a flowchart for operating an identification transmitter according to the present invention.

1 shows an identification transmitter 1 a locking system of a vehicle, and the identification transmitter 1 can be performed for example in the form of a check card, or the identification transmitter 1 is executed integrated in the key of the vehicle.

The identification transmitter 1 is part of a locking system of the vehicle and is designed to identify an authorized person to unlock the vehicle and / or allowed to start.

The identification transmitter 1 has a receiving unit 10 on, which is designed to receive a transmission signal which can be emitted by a transceiver module in the vehicle. The receiving unit 10 can receive coils 17 in particular, three receiving coils 17 in a mutually orthogonal arrangement in the identification transmitter 1 be provided. Thus, the transmission signal from the transceiver module regardless of the spatial position of the receiving unit 10 be received. The transmission signal is designed in particular as an LF signal and forms an H field with an alternating frequency of, for example, 125 kHz. As a result, in at least one receiving coil 17 a current can be induced by the microprocessor 11 can be sensed. The receiving unit 10 thus becomes part of the microcontroller 11 together with the receiver coils 17 educated.

The identification transmitter 1 is still with an energy storage 12 executed, which is to power at least the receiving unit 10 and the microcontroller 11 , but especially for the power supply of the motion sensor 13 serves. Furthermore, it is located in the identification transmitter 1 an RF module 14 that has an antenna 15 an identification signal to the transceiver module in the vehicle can send back, for example, the authorized person in possession of the identification transmitter 1 is to authenticate.

The motion sensor 13 is in connection with the microcontroller 11 shown, which is then switched off according to the invention, when the motion sensor 13 for a minimum period of time, a motionlessness of the identification transmitter 1 sensed.

With shutdown of the receiving unit 10 can prolong the life of the energy store 12 be achieved, both the microcontroller 11 with the receiving unit 10 as well as the RF module 14 powered. The quiescent current from the microcontroller 11 and from the receiving unit 10 from the energy store 12 can, in the on state of the receiving unit 10 be about 6 uA. Switches the microcontroller 11 the receiving unit 10 off when the motion sensor 13 no movement of the identification transmitter over a minimum period of time 1 senses more, so can the quiescent current when the receiver unit is switched off 10 be lowered to 0.4 uA.

Only when through the motion sensor 13 again a movement of the identification transmitter 1 is sensed, for example, if the authorized person the identification transmitter 1 takes in hand, and / or if on the the identification transmitter 1 existing switching means 16 is operated manually by the authorized person, the receiving unit 10 through the microcontroller 11 be activated again. The switching means 16 For example, are designed as a button to unlock the vehicle with this lock, or to open or close only a particular flap on the vehicle, for example. Senses the microcontroller 11 an actuation of at least one switching means 16 , then so can the receiving unit 10 be converted back into the activated state.

2 shows a flowchart of a method for operating the locking system for the vehicle with an identification transmitter 1 the in 1 described type. In switching state A, the receiving unit 10 as well as the switching means 16 be activated. Furthermore, in the microcontroller 11 a timer may be present which serves to determine the time until the minimum duration is reached and which may also be activated.

If the minimum period of time is determined in the query X, after the reception unit has failed 10 a transmission signal was received nor a switching means 16 has been pressed, so when reaching the minimum period of time, the state of the identification transmitter 1 be converted to the intermediate state D, marked with "YES". If the minimum time is not reached by switching means before the minimum time has elapsed 16 is pressed or the receiving unit 10 receives a transmission signal, the state of the identification transmitter remains 1 in state A, marked "NO".

The switching state D describes a state of the identification transmitter 1 in which both the motion sensor 13 , as well as the switching means 16 , the receiving unit 10 , the timer in the microcontroller 11 and the microcontroller 11 themselves are active. In this case, both the time period that is measured by the timer until the minimum time duration is reached, as well as the period of time after which the switching means 16 last reset, be reset. Reaches the switching state D of the identification transmitter 1 the minimum period of time, the switching state D is transferred to the intermediate state B, marked with "YES". If the minimum duration is not reached, then after the reset of the motion sensor 13 and the switching means 16 the switching state D of the identification transmitter 1 be returned to the switching state A, marked with "NO". In this case, the query of reaching the minimum period of time is marked by Y.

The intermediate state B describes a state of the identification transmitter 1 in which the motion sensor 13 and the switching means 16 are active, the receiving unit 10 , the timer in the microcontroller 11 and the microcontroller 11 yourself are disabled. In this case, a quiescent current of only 0.4 μA sufficient, the energy storage 12 must be provided.

The receiving unit 10 may also be formed for the periodic query of the reception of the transmission signal from the transceiver module in the vehicle, wherein the periodic polling of the reception is also referred to as polling. If a polling takes place, then the intermediate state C can be reached, in which the motion sensor 13 and the switching means are active, and the receiving unit 10 and the microcontroller 11 are disabled. However, the timer is in the microcontroller 11 active to operate the polling.

Finds a movement of the identification transmitter 1 instead, so can the motion sensor 13 emit a corresponding signal or it may be a switching means 16 be actuated, represented by the query Z. Senses the motion sensor movement of the identification transmitter 1 , and / or becomes a switching means 16 at the identification transmitter 1 actuated, the intermediate state B or intermediate state C can be converted back into the switching state D, marked with "YES". Remains the identification transmitter 1 in the intermediate state B or in the intermediate state C, the query Z is marked with "NO".

The invention is not limited in its execution to the above-mentioned preferred embodiment. Rather, a number of variants is conceivable, which makes use of the illustrated solution even with fundamentally different types of use. Any features and / or advantages resulting from the claims, the description or the drawings, including constructive details, spatial arrangements and method steps, can be essential to the invention, both individually and in the most diverse combinations.

LIST OF REFERENCE NUMBERS

1

identification transmitter

10

receiver unit

11

microcontroller

12

energy storage

13

motion sensor

14

RF module

15

antenna

16

switching means

17

receiving coil

A

switching status

B

intermediate state

C

intermediate state

D

switching status

X

Query Reach Minimum period of time in switching state A

Y

Query Reach Minimum period of time in switching state D

Z

Query movement sensor and / or switching means

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19927253 C2 [0002]

Claims (11)

Identification transmitter ( 1 ) a locking system of a vehicle, designed to identify an authorized person to unlock the vehicle and / or to start, with - a receiving unit ( 10 ), which is designed to receive a transmission signal that can be transmitted by a transceiver module in the vehicle, - a microcontroller ( 11 ) for controlling the receiving unit ( 10 ), and with - an energy store ( 12 ) for supplying energy to at least the receiving unit ( 10 ) and the microcontroller ( 11 ), - a motion sensor ( 13 ) used to sense a movement of the identification transmitter ( 1 ), characterized in that - at least the receiving unit ( 10 ) through the microcontroller ( 11 ) can be switched off, - if the motion sensor ( 13 ) for a minimum period of time a motionlessness of the identification transmitter ( 1 ) senses. Identification transmitter ( 1 ) according to claim 1, characterized in that the shutdown of the receiving unit ( 10 ) at least one non-functional setting of the receiving unit ( 10 ), in particular that the shutdown leads to a reduction of the current consumption of the identification transmitter ( 1 ) leads to a maximum of 2μA, in particular to a maximum of 0.4μA. Identification transmitter ( 1 ) according to claim 1 or 2, further comprising an RF module ( 14 ) for communication with the transceiver module in the vehicle, the communication comprising a query as to whether the identification transmitter ( 1 ) located inside or outside the vehicle. Identification transmitter ( 1 ) according to claim 1 to 3, characterized in that the receiving unit ( 10 ) is designed for periodic polling of the reception of the transmission signal from the transceiver module in the vehicle. Identification transmitter ( 1 ) according to one of the preceding claims, characterized in that the microcontroller ( 11 ) for the diagnosis of the motion sensor ( 13 ) is formed such that by means of the microcontroller ( 11 ) a defect of the motion sensor ( 13 ) is diagnosable. Identification transmitter ( 1 ) according to one of the preceding claims, characterized in that the microcontroller ( 11 ) can be brought into an intermediate state (B), in which the supply current of the microcontroller ( 11 ) through the energy store ( 12 ) is less than 1μA, especially less than 0.4μA. Method for operating a locking system for a vehicle with an identification transmitter ( 1 ) for identifying an authorized person to unlock the vehicle and / or to start, with - a receiving unit ( 10 ) for receiving a transmission signal from a transceiver module in the vehicle, - a microcontroller ( 11 ) for controlling the receiving unit ( 10 ), - an energy store ( 12 ) for supplying energy to at least the receiving unit ( 10 ) and the microcontroller ( 11 ), - a motion sensor ( 13 ), by which a movement of the identification transmitter ( 1 ) is characterized, characterized by at least the following method steps: - determining a period of time by the microcontroller ( 11 ) in conjunction with the motion sensor ( 13 ), whether the identification transmitter ( 1 ) is unmoved over the period of time, - comparison of the duration of immobility with a minimum period of time and Procedure ( 1 ) according to claim 7, characterized in that by the identification transmitter ( 1 ) is queried by means of a communication with the transceiver module in the vehicle, whether the identification transmitter ( 1 ) located inside or outside the vehicle. Procedure ( 1 ) according to claim 8, characterized in that when the identification transmitter ( 1 ) is in the vehicle, the minimum period of time for switching off the receiving unit ( 10 ) through the microcontroller ( 11 ) at least 30 minutes, preferably at least 1 hour. and more preferably at least 2 hours. Procedure ( 1 ) according to claim 7, characterized in that when the identification transmitter ( 1 ) is outside the vehicle, the minimum time for switching off the receiving unit ( 10 ) through the microcontroller ( 11 ) at most 10 minutes, preferably at most 5 minutes. and more preferably at most 2 minutes. is. Procedure ( 1 ) according to one of claims 7 to 10, characterized in that the vehicle has a display means, via which the authorized person is requested, the identification transmitter ( 1 ), in particular if the identification transmitter ( 1 ) is in the vehicle and has not been moved over the minimum period of time and in particular by the authorized person the intention is signaled to start the vehicle.

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