DE102004027462B4 - A method for teaching a portable ID transmitter with an immobilizer secret from an immobilizer system in a vehicle, as well as immobilizer system - Google Patents

Abstract

Method for teaching a portable ID transmitter (3) with an immobilizer secret from an immobilizer system (2) in a vehicle (1),
- wherein the ID transmitter (3) via suitable communication means (6, 7) can communicate wirelessly with the immobilizer system (2),
- wherein the ID transmitter (3) both a microcontroller (5) as part of a keyless-entry-keyless-go system,
- As well as a transponder (4) for a manual operation of the immobilizer system (2), characterized in that
- The microcontroller (5) is pre-programmed with pre-learning data with already known data, wherein
- Read a transponder ID from the transponder (4) of the ID transmitter (3) during pre-programming and in the microcontroller (5) of the same ID transmitter (3) is written, wherein
- Subsequently, a data communication between the immobilizer system (2) and the transponder (4) takes place, wherein read out within an at least partially cryptic data communication, the transponder ID of the immobilizer system (2) and the immobilizer secret of Immobilizer system (2) is written in the transponder (4), wherein
- An unambiguous assignment between the immobilizer system (2) and the transponder (4) is made by the transponder ID, wherein
- In a subsequent step of the microcontroller (5) by the previously made clear assignment between transponder (4) and immobilizer system (2) is also clearly assigned, and
- The immobilizer system (2) transmits the immobilizer secret in the case of a clear assignment to the microcontroller (5).

Description

STATE OF THE ART

The present invention relates to a method for teaching a portable ID transmitter with an immobilizer secret from an immobilizer system in a vehicle according to the preamble of claim 1, as well as an immobilizer system according to the preamble of claim 9.

ID encoders are used in particular in the field of vehicle technology, for example in connection with immobilizers and door locking systems. In this case, the ID transmitter is a portable unit that can communicate wirelessly with an immobilizer system in the vehicle, for example, an immobilizer and / or a door lock mechanism can be controlled in a suitable manner.

Now different driving strategies are known with which the communication between the base and the ID transmitter can be realized. One strategy has become known as the "keyless-entry-keyless-go" system. In principle, the user does not have to participate actively in the authentication process between the immobilizer system and the ID transmitter. The ID transmitter contains a so-called microcontroller (μC), which can enter, for example by touching a door handle of the vehicle in a wireless communication with the immobilizer system. If the microcontroller has an immobilizer secret (WFS secret) corresponding to the immobilizer system, the immobilizer is disabled. The WFS secret is advantageously a 7-byte long data sequence.

In another strategy, the user must actively actuate a transponder in the ID transmitter, for example by a button, to initiate communication between the ID transmitter and the immobilizer system. Again, the immobilizer can be disabled, provided that the transponder can transmit the correct WFS secret.

It is now also known to combine both systems in one ID transmitter, the transponder being provided merely as a replacement system for the microcontroller for the keyless entry keyless go system. The transponder, for example, should only be used in the event that the battery of the microcontroller is empty. However, it is by no means impossible to use the transponder in parallel with the microcontroller.

From the publication DE 100 04 615 C2 An ID transmitter with a transponder and a microcontroller is known. Other, prior art disclosing publications are the publications DE 197 37 874 C1 . DE 196 17 251 C2 . DE 101 12 573 C2 . DE 195 33197 A1 and EP 1 325 848 A2 ,

The problem, however, is that the WFS secret, which is basically stored in the immobilizer system of the vehicle, must be written both in the transponder and in the microcontroller. On the other hand, the immobilizer system of the vehicle, the identification data of the transponder, the so-called transponder ID, and the identification data of the microcontroller must be announced.

A method for teaching a portable ID transmitter is basically also from the document DE 100 04 615 C2 known. However, details of how to do the method of teaching the portable ID transmitter are not given. In particular, the document does not describe how the two components of the ID transmitter, the transponder and the microcontroller are taught, so that both immobilizer secrecy is known.

Accordingly, it is first object of the present invention to provide a method by which the WFS secret of the immobilizer system can be written in a straightforward manner both in the transponder and in the microcontroller.

ADVANTAGES OF THE INVENTION

According to the invention the object is achieved by a method having the characterizing features of claim 1. The proposed method makes it particularly easy and with a high degree of process reliability to implement the teaching of an ID transmitter with a separate transponder and microcontroller for a keyless entry keyless go system.

It also advantageously lends itself to the fact that the immobilizer secret is a 7-byte long data sequence. This can ensure a high level of security.

For safe control of the microcontroller may further advantageously be provided that the microcontroller by means of a wake-up signal (WUP) can be awakened, the wake-up signal (WUP) is generated from the transponder ID.

It may also be advantageously provided that a bidirectional data Communication comprising an uplink data stream and a downlink data stream between the immobilizer system and the ID transmitter via the communication devices.

As advantageous embodiments of the communication devices can be provided that the uplink data stream is transmitted through an LF read coil and the downlink data stream through a UHF system or that the uplink data stream through an LF vehicle interior antenna and the downlink data stream through a UHF System is transmitted. It can also advantageously be provided that both the uplink data stream and the downlink data stream are transmitted by an LF read coil, or that both the uplink data stream and the downlink data stream are transmitted by a UHF system.

Another object of the present invention is to provide an immobilizer system for a motor vehicle having an ID transmitter comprising a transponder and a microcontroller, wherein the ID transmitter can be easily learned with immobilizer secrecy.

According to the invention this object is achieved by an immobilizer system with the characterizing features of claim 9.

list of figures

• 1 eine schematische Darstellung der Komponenten eines erfindungsgemäßen Wegfahrsperrensystems.

Further features and advantages of the present invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings. Show in it

• 1 a schematic representation of the components of an immobilizer system according to the invention.

DESCRIPTION OF THE EMBODIMENTS

An immobilizer system 2 for a vehicle 1 is an ID donor 3 associated with transmitting and receiving devices 6 . 7 are provided to a wireless bidirectional data communication between the immobilizer system 2 and the ID transmitter 3 to enable.

The portable ID transmitter 3 essentially comprises a transponder 4 with a transponder ID and a microcontroller 5 , where the microcontroller 5 is suitable for controlling a keyless-entry-keyless-go system, which basically in the immobilizer system 2 can be integrated.

Basically, the ID transmitter 3 both via the transponder 4 as well as the microcontroller 5 for controlling the immobilizer system 2 suitable. While the control via the transponder 4 manually, for example via a button on the ID transmitter 3 done, the immobilizer system can 2 together with the microcontroller 5 be controlled via a keyless-entry-keyless-go system. Within the scope of this activation no active contribution of the user is necessary. The keyless-entry-keyless-go system may be triggered, for example, by a door handle proximity sensor.

Preferably, the transponder 4 designed as a backup system. This is to ensure that the immobilizer system 2 continue via the ID transmitter 3 can be controlled, even if the microcontroller 5 , for example due to a defective battery, should fail.

A prerequisite for both activation methods is a so-called immobilizer secret, which takes the form of a preferably seven-byte long code in the immobilizer system 2 present, wherein the ID transmitter 3 must be "trained" with the immobilizer secret, thus a secure authentication between the immobilizer system 2 and the assigned ID transmitter 3 can take place.

For teaching the ID transmitter 3 Now according to the invention the following method is provided.

Teaching is basically divided into two process steps.

First, a preprogramming takes place. In this, the immobilizer secrecy of the immobilizer system must 2 both in the transponder 4 as well as in the microcontroller 5 to be written. For this purpose, the ID transmitter 3 pre-programmed with various previously known data before the actual teach-in process. During this preprogramming, the transponder ID is removed from the transponder 4 of the ID transmitter 3 read out and into the microcontroller 5 of the same ID transmitter 3 written.

For the actual learning process, the transponder is first 4 of the ID transmitter 3 learned. For this purpose, the transponder ID is read out within a partly cryptic communication and essentially the immobilizer secret in the transponder 4 written. Below is the microcontroller 5 learned. This can be clearly addressed, since the system via the previously learned transponder ID a unique assignment to the still learning microcontroller 5 Has. The identification now takes place via the preprogrammed transponder ID, which is read out and learned by the system. The vehicle 1 or the immobilizer system 2 gives the immobilizer secret to the microcontroller 5 from.

It can also be provided that the microcontroller 5 can be aroused in a safe and unambiguous way. For this purpose, the microcontroller is awakened by means of a wake-up signal (WUP). To avoid having another microcontroller 5 Nearby affects the communication, the wake-up signal must be unique. To solve this problem, the wake-up signal for the learning process is generated from the transponder ID so that it is unique. The transponder ID was during pre-programming from the associated transponder 4 transfer.

In addition, different transmission options for biddirektiohale data communication to the microcontroller 5 conceivable. Basically, bidirectional data communication includes an uplink data stream and a downlink data stream, where the uplink data stream may be transmitted through an LF read coil and the downlink data stream through a UHF system.

It is also conceivable that the uplink data stream is transmitted through an LF vehicle interior antenna and the downlink data stream through a UHF system.

Furthermore, it is provided in a technically favorable variant that both the uplink data stream and the downlink data stream are transmitted through an LF read coil.

Furthermore, it can also be provided that both the uplink data stream and the downlink data stream are transmitted by a UHF system. Due to the generally higher range of the UHF signal compared to the LF signal, precautions must be taken, for example, if several production lines are next to each other.

Claims (9)

A method for teaching a portable ID transmitter (3) with an immobilizer secret from an immobilizer system (2) in a vehicle (1), - wherein the ID transmitter (3) via wireless communication devices (6, 7) with the immobilizer system (2 ) - wherein the ID transmitter (3) comprises both a microcontroller (5) as part of a keyless-entry-keyless-go system, - and a transponder (4) for manual actuation of the immobilizer system (2), characterized in that - the microcontroller (5) is preprogrammed prior to the learning process with already known data, wherein - read a transponder ID from the transponder (4) of the ID transmitter (3) during pre-programming and into the microcontroller (5) the same ID transmitter (3) is written, wherein - then a data communication between the immobilizer system (2) and the transponder (4) takes place, wherein within an at least partially cryptic Datenkommunikati the immobilizer secret of the immobilizer system (2) is written to the transponder (4), whereby - an unambiguous association between the immobilizer system (2) and the transponder (4) by the transponder ID is carried out, wherein - in a subsequent method step, the microcontroller (5) is also uniquely assigned by the previously made unique assignment between transponder (4) and immobilizer system (2), and - the immobilizer system (2) the immobilizer secret in case of a unique assignment transmits to the microcontroller (5). Method according to Claim 1 , characterized in that the immobilizer secret is a 7 byte long data sequence. Method according to one of Claims 1 or 2 , characterized in that the microcontroller (5) can be woken up by means of a wake-up signal (WUP), wherein the wake-up signal (WUP) is generated from the transponder ID. Method according to one of Claims 1 to 3 , characterized in that a bidirectional data communication comprising an uplink data stream and a downlink data stream between the immobilizer system (2) and the ID transmitter (3) via the communication means (6, 7) takes place. Method according to Claim 4 , characterized in that the uplink data stream is transmitted through an LF read coil and the downlink data stream through a UHF system. Method according to Claim 4 , characterized in that the uplink data stream is transmitted through an LF vehicle interior antenna and the downlink data stream through a UHF system. Method according to Claim 4 , characterized in that both the uplink data stream and the downlink data stream are transmitted through an LF read coil. Method according to Claim 4 , characterized in that both the uplink data stream and the downlink data stream are transmitted through a UHF system. Immobilizer system (2) for a motor vehicle (1), - having an immobilizer system (2) suitable for wireless communication with a portable ID transmitter (3), wherein - the ID transmitter (3) is connected via a transponder (4) and a microcontroller (5) for a keyless entry keyless go system, wherein - the transponder (4) is assigned a unique transponder ID, wherein - the immobilizer system (2) has an immobilizer secret, characterized in that the ID transmitter (3) by a method according to at least one of Claims 1 to 8th is programmed with the immobilizer secret.

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