DE10315845B4 - System, system components and method for processing a hermetically validatable data transfer - Google Patents

Abstract

Method for processing a data transfer between a master system (encoder) and a slave system (receiver) based on capacitive interaction effects in which a signal event is emitted by the master system into a receiving area of the slave system and a pilot sequence is emitted by the master system and during the input of the Pilot sequence the input impedance of the slave system is modulated in accordance with a data pattern,
whereby the modulated change of the input impedance of the slave system is detected by the master system, and
wherein a data set is generated from the modulation pattern of the input impedance of the slave system detected by the master system and this data record is authoritative for the information content or for the permissibility of a continuation of the data transfer from the master system to the slave system.

Description

Territory of invention

The The invention relates to a system whose system components and a method for handling a data transfer in one in terms of validity a sender and / or receiver tested way. Furthermore, the invention is concerned with a quasi-unidirectional Dialogue system for processing a data transmission, in particular via the human body or at least the proximity environment of a user.

background the invention

In the case of radio-based data transmission systems, there is the problem that due to the propagation of the radio waves, unauthorized persons with suitable receivers can record and misuse data (see FIG. 1 ).

In particular, systems including electromagnetic transponders can be misused, even if the transponder is far away from a recognizing reader. For this purpose, the transponder is stimulated to transmit, and transmits the data detected by radio to a "transponder simulator" approximated to the reader, which pretends to the reader that the real transponder is located nearby.This makes possible data sequences for unauthorized access The principle of such coverage bridging is in 2 illustrated.

To avoid these problems, so-called challenge / response solutions were developed. In this case, bidirectional keywords are exchanged between a data transmitter and a reaction device. In addition to a complex procedure (protocol), which makes this possible, both data transmitter and reaction device must be provided with transmitting and receiving devices and be operated alternately with a controller. (S. 3 ).

Has been the data transmission earlier initiated with a push of a button (for example, the radio car key), which shows Technology today so-called keyless access systems, where it is sufficient with a transceiver to enter the radio range of a reaction device. But that occurs Again, the problem of range bridging on.

For challenge / response systems also results the problem that a strong, radiated from a jammer carrier at the same frequency, the system can prevent it from transmitting data. This Circumstance allows it, abusive to prevent a user-intended door closing operation, so that an owner of a motor vehicle away from this Believing that it is closed because he is either from the Keyless access detection area removed or a closing button of its Car door remote control operated. A thief equipped with a suitable hand-held transmitter that emits a permanent carrier, can the closing process from a distance, prevent objects from being removed steal the vehicle. The damaged owner may be opposite to his Insurance does not prove that the vehicle was locked. As a special problem could also find that other electronic systems, a user or uninvolved persons by the constant radio wave exposure impaired in health become.

Around to reduce the effort and comfort of a remote-controlled data transmission raises the technology solutions ready to transfer the data over the human body to a contact or approach sensitive Transmit the recipient.

Out EP 0 843 425 A2 Dialogue system is known for handling a data transfer between a user-guided identification circuit and a receiving system based on field-electrical interaction effects. In this dialog system, a time information signal is taken into account in the handling of the data exchange for manipulation prevention on the encoder and receiver sides. This ensures that a suitable signal transmitter is located near the receiver at the time of data transmission. The receiver thus works synchronously with the encoder, thereby ensuring that the code can not be illegally copied in the past and used at a later time at the receiver (timestamp).

Out WO 99/37044 A1 is a data transmission system for transmission information from the area of a borehole bottom to a above-ground monitoring system known. This system uses data from an electrically conductive drill pipe transmitted from a near-the-bore measuring system to that aboveground monitoring system. The data transfer is accomplished by placing in the area of the drill head by an electronic circuit to the electrical connection one opposite the drill pipe isolated, but otherwise grounded section is modulated. The thereby changed effective change the earthing of the drill string can be in the area of the surveillance system detected as an impedance change become. Since the impedance is corresponding to the side of the drill electronic circuit modulated electrical connection with the isolated section changes, will it be possible based on the aboveground detectable impedance change the modulation pattern to recognize the drill near the circuit arranged and from this To gain data.

Out DE 44 30 360 C1 An anti-theft system for a motor vehicle is known. This system comprises a portable transponder carrying code information and a stationary resonant circuit. The stationary resonant circuit is modulated with the code information when the transponder is in the vicinity of the resonant circuit. If, on the part of the stationary oscillating circuit, no desired code information can be obtained from the signal provided by the transponder, the excitation or resonance frequency of the oscillating circuit is changed in a defined manner.

Out US Pat. No. 6,388,575 B1 For example, an addressable underground location system is known which serves to detect underground objects, eg cables above ground. The underground location system comprises an electronic circuit which has a resonant circuit which is provided with a coil which can be acted on by a B-field generated above ground by a search system. In the resonant circuit, a circuit section is integrated, which makes it possible to change the impedance of the resonant circuit in accordance with a data set this impedance change can be detected aboveground and be and allows extraction of the data set.

Out US 3 427 614 A a telemetry system is known, which serves to enable a signal transmission from a transmitter system to a receiver system. The signal transmission is accomplished in this telemetry system by transmitter and receiver each have resonant circuits which interact inductively, or capacitively with each other. Due to the extent existing coupling of the resonant circuits, it is possible to detect changes in properties of the transmitter-side resonant circuit in the region of the receiver-side resonant circuit and thereby transmit signals from the transmitter-side resonant circuit to the receiver-side resonant circuit.

Task of invention

Of the Invention is based on the object, a system, system components the same and a procedure for settling one's way through one high security against tampering, to create data transfers.

Inventive solution

The Previously stated object is achieved by a system according to claim 1.

Of the Invention is based on the approach, a data transfer between to handle a master system and a slave system in a way which makes it possible In the area of the master system information about the slave system based on to gain the signal recording properties of the same. Especially the invention shows a solution on, in which a data transfer between the master system and the slave system takes place capacitively, wherein the input impedance of the slave system in accordance with a defined data pattern is modulated and this data pattern in the area of the master system during the signal transmission is detected.

Thereby is it possible in an advantageous manner Information in particular in the form of a key data sequence in a quasi-hermetic Shielded way to a master or transmitting system due and this key data sequence one for the further data transfer or data exchange authoritative Signal generation and / or signal validation basis.

Under the term master system is understood in context to mean a system which is capable of a signal sequence directed to an addressee leave. The term slave system in the context is a system to be able to understand one part of the master system to capture the provided data sequence. It may be enough the master or the slave system with a respect to its input impedance equip modulatable receiving device. In vote on the particular application, it is possible circuit technology or more complex circuit structures in terms of data processing to relocate to the area of the master or slave system.

in the Area of the master system are advantageously made of the, data obtained from the recording behavior of the slave system based on which an encryption of the part of the slave system further transmitted data takes place.

in the Area of the slave system can be advantageously generated of for the modulation of the input impedance relevant data pattern a time value considered become.

Preferably be in the range of the slave system for the modulation of the input impedance Information content of the signals generated by the master system considered. Especially the invention shows a solution on, in which a data transfer between the master system and the slave system takes place capacitively, wherein the input impedance of the slave system in accordance with a defined data pattern is modulated and this data pattern in the area of the master system during the signal transmission is detected.

Thereby is it possible in an advantageous manner Information in particular in the form of a key data sequence in a quasi-hermetic Shielded way to a master or transmitting system due and this key data sequence one for the further data transfer or data exchange authoritative Signal generation and / or signal validation basis.

Under the term master system is understood in context to mean a system which is capable of a signal sequence directed to an addressee leave. The term slave system in the context is a system to be able to understand one part of the master system to capture the provided data sequence. It may be enough the master or the slave system with a respect to its input impedance equip modulatable receiving device. In vote on the particular application, it is possible circuit technology or more complex circuit structures in terms of data processing to relocate to the area of the master or slave system.

in the With regard to the concrete handling of the data transfer, the solved at the beginning of the task by a method for handling a data transfer between a master system (encoder) and a slave system (receiver) which on the part of the master system a signal event in a reception area of the slave system and the reception pickup properties of the slave system defined modulated and on the part of the master system be recognized and evaluated.

Of the Data transfer is preferably based on capacitive interaction effects settled.

Preferably is emitted by the master system a pilot sequence and during the Input of the pilot sequence the input impedance of the slave system in accordance with a data pattern is modulated.

by of the master system is preferably the modulated change the input impedance of the slave system detected.

Out the modulation pattern of the input impedance detected by the master system of the slave system, a record is generated in an advantageous manner and this dataset is authoritative for the Information content or for the admissibility a continuation of the data transfer from the master system to the Slavesystem considered.

in the Area of the master system are advantageously made of the, data obtained from the recording behavior of the slave system based on which an encryption of the part of the slave system further transmitted data takes place.

in the Area of the slave system can be advantageously generated of for the modulation of the input impedance relevant data pattern a time value considered become.

Preferably be in the range of the slave system for the modulation of the input impedance Information content of the signals generated by the master system considered.

The Modulation of the input impedance of the slave system is preferably carried out with recourse to an encryption procedure.

The on the part of the slave system to provide the for the modulation the input impedance relevant Data pattern used encryption procedure, can be advantageously based on information content the signal sequence output by the master system or be voted on.

In Advantageously, a congruence analysis takes place in the context of the dialogue recording first based on a low level of encryption, the encryption level subsequently is raised.

The for the raised encryption level authoritative Information content can at least initially at lower encryption level be transported.

About the Master system can advantageously one, as an authorization identifier evaluated signal sequence depending on the application permanently, pulsed or selectively dispensed.

It is possible, To design the master system in such a way that it changes the configuration of the master system allows the signals obtained by impedance modulation.

Of the Data transfer between the master system and the slave system can in an advantageous manner for processing a number, posting, value-added or proof of access.

Of the Data transfer between the master system and the slave system can also for carrying out a process for changing the locking state a motor vehicle are used.

Of the Data transfer between the master system and the slave system can in a further advantageous manner also for the function release of equipment be used.

According to one particular aspect of the present invention, the data transfer between the master system and the slave system for performing a presence analysis be used to determine the equipment scope or the entrance or exit self-identifying articles.

The The invention also relates to a system for handling a Data transfers with a master system component (encoder) and a Slave system component (receiver), wherein the master system component is designed such that it is suitable, a signal event in a receiving area of the slave system component into it, and the slave system component is formed is that this makes it possible to define the reception receiving properties of the same modulated taking precautions in the area of the master system component are the changes to detect the reception characteristics of the slave system component and based on this detection, the further data transfer determine.

Farther The invention also includes a master system component for an above specified system, which has a signal output device as a surface electrode is trained.

These Master system component preferably comprises an electronic signal processing device, wherein the signal processing device preferably access to a key data storage device Has.

The Master system component can be accommodated in an advantageous manner in a check card-shaped main body be.

The Master system component may be part of a vehicle key system form.

The invention is also directed to a slave system component for a system of the above mentioned type, having a receiving device for receiving input events on the basis of capacitive interaction effects.

The Slave system component advantageously comprises a receiving device in the area of a cash register system, a person passage area, a sales system or equipment, for example for activation the same is arranged.

The Slave system component may also be part of a vehicle door locking system form.

The The invention is also directed to a method of modification the locking state of a motor vehicle under settlement a data transfer between a master system (encoder / key) and a Slave system (receiver / vehicle-side Circuit component) in which part of the master system Signal event in a receiving area of the slave system inside is released and the reception recording properties of the slave system Defined modulated and recognized and evaluated by the master system become.

The Task distribution or assignment of the master system and the slave system can also be inverted. The invention thus also includes a procedure for change the locking state of a motor vehicle under settlement a data transfer between a master system (key device) and a slave system (vehicle-side circuit component) which on the part of the slave system a signal event in a reception area of the master system and the reception recording properties the master system defines modulated and on the part of the slave system be recognized and evaluated

Of the Data transfer is advantageously based on capacitive Interaction effects settled.

Further Details of the invention will become apparent from the following description in conjunction with the drawing. It shows:

1 a per se known, a transmitter and a receiver comprehensive data transmission system, as well as a provided listening system that allows an inadmissible information picking;

2 a per se known electromagnetic transponder system in which a data transfer between the transponder and a reader is accomplished by improper interposition of a snooping system;

3 a schematic representation for explaining a Challenge / Response system;

4 a schematic representation for explaining a system according to the invention for carrying out a hermetic signal feedback by modulation of the receiving impedance in the region of the receiver;

5 a schematic representation for a more detailed explanation of the system 4 ;

6 a diagram explaining the activity sequence in the area of the master system (encoder) and the slave system (receiver).

In the following, a method is presented which easily implements a dialog system that can solve the above-mentioned problems. This is a capacitive transfer of data, preferably via the skin of a user. Since this is in principle an AC circuit, a change in the (eg ohmic) load of the receiver input stage can be determined on the transmitter side. This change can be made in a determinable rhythm (so-called load telegram BT s. 4 ).

• 1. das er sich in der Nähe eines Empfängers befindet
• 2. um welchen Empfänger es sich handelt, wenn das BT eine Kennung enthält
• 3. auf welche Weise (Frequenz, Code, Schlüssel etc.) bestimmte Daten übertragen werden sollen
• 4. ob die Übertragung gestört wird, BT aufgrund eines Störträgers nicht korrekt lesbar

The encoder first generates a short (eg 1ms) pilot tone at irregular intervals (repetitive), eg 5 times per second. When approaching the capacitive coupling point, this frequency is detected by the receiver, which then immediately generates a load telegram (BT). The donor (transmitter) can "recognize" this:

• 1. that he is near a receiver
• 2. Which recipient it is, if the BT contains an identifier
• 3. in which way (frequency, code, key, etc.) certain data should be transmitted
• 4. if the transmission is disturbed, BT not correctly readable due to a fault carrier

A "listener" would only the pilot tones can detect because he forms his own burden circle to the donor (Not however to the receiver). On by the receiver remote location could anyway, only the repetitive pilot tones are "bugged", due to the missing load telegram "recognizes" the donor, he is not near the recipient and drives continue to output the pilot tone cyclically.

Of the Receiver changes each pilot tone its load telegram. He "recognizes" a sturgeon carrier at the excess length (permanent carrier) disorder cyclic, as the pilot tones, so could due to the irregular output the "real" pilot tones always one or the other "slip through." A detected disorder can to trigger an alarm or e.g. a closure be initiated or otherwise signaled. There on a pilot tone from the encoder an ID number encrypted by the load telegram must be issued, the recipient may be the failure of such also notice.

principle of operation

An oscillator (which can also be designed as a VCO) generates the transmission fundamental frequency (typically some 100 kHz). A controller ensures that the pilot tones are initially output via a mixer (ASK / FSK or similar) selectively or cyclically if necessary at irregular intervals. When approaching a receiver this generates a load telegram (eg by short circuit of Rb), which has alternating voltage drops at the resistor Rx of the encoder result. These can be supplied via a differential amplifier of the controller, for example. This decodes the load telegram and encrypts the encoder code to be transmitted accordingly. The result is again output via the mixer, amplified by the receiver, decoded and fed to a code evaluation. At the receiver, components or components may remain in a low power state until a pilot tone is received. Thus, a comfortable and secure dialogue system with many advantages can be realized in a simple manner and with little effort (s. 5 ). The load of the AC circuit can be done by turning on or off an ohmic resistance and / or a capacitance and / or an inductance. The switching process itself can be done by a transistor, FET, CMOS switch etc; An optocoupler can also be used.

A first preferred embodiment

• 1. Absicht eines, mit mindestens einem Codegeber ausgestatteten Benutzers, eine identifizierbare Handlung auszuführen (z.B. das Öffnen einer verschlossenen Tür).
• 2. Annäherung (z.B. mit der Hand) an die Koppelfläche eines Empfängers, damit Aufbau eines Wechselstromkreises; die Rückführung erfolgt über parasitäre Kapazitäten.
• 3. Empfänger „erkennt" die unregelmäßigen Pilottöne
• 4. Er erzeugt ein Belastungstelegramm durch Impedanz-Änderung der Eingangstufe in einem zufälligen jedoch sinnvollen Rhythmus.
• 5. Der Geber dekodiert aus dem Belastungstelegramm BT eine Handlungsanweisung
• 6. Damit verschlüsselt er seine Identifizierungsdaten, und wählt z.B. eine Übertragungsfrequenz, Baudrate und Übertragungsverfahren aus (z.B. ASK, FSK usw.) (s. 6)
• 7. Der Geber gibt die verschlüsselten Signale aus und erzeugt anschließend wieder einen Pilotton
• 8. Der Empfänger verstärkt, dekodiert und entschlüsselt die Gebersignale
• 9. Bei Übereinstimmung einer bestimmten Codefolge wird ein Impuls ausgegeben, z.B. zum Öffnen eines Verschlussmechanismus (evtl. über ein Steuergerät).
• 10. Beim nächsten Pilotton gibt er dem Empfänger eine „OK"-Meldung und weitere Informationen über ein neues Belastungstelegramm. In dem Belastungstelegramm können Informationen enthalten sein, die vom Codegeber stammen oder durch diesen veranlasst wurden.
• 11. Wenn sich der Benutzer entfernt, bricht der Dialog ab. Der Geber generiert dann nur noch Pilottöne und der Empfänger meldet die Entfernung (z.B. Schließbefehl).
• 12. Zwischendurch „untersuchen" Geber und Empfänger ständig Ihre Umgebung nach Störungen.

Wherever a secure identification within an action is to take place (action-integrated identification), one or more encoders can be accommodated by a user close to the body. This can be done in many ways, for example, smart cards or key chains, jewelry or clothing or other items carried (purses, wallets) donors included. When approaching a user eg with his hand to a receiver, the quasi-bidirectional dialogue takes place because an AC circuit with capacitive coupling surfaces arises. Upon transmission of identifying data, the receiver, upon agreement, may output a signal which, for example, causes an electromechanical locking device to open a (door) shutter. While the action to be identified takes place, a new dialogue with different load telegrams is constantly conducted in the rhythm of the pilot tones. A distance from the receiver causes the latter to automatically issue a closing pulse which can be used internally and externally. Keyless access systems thus receive a new quality because the capacitive method works between two approaching surfaces and does not require a (audible) radio range. In addition, the rule of thumb is that if an encoder can recognize and decode a load telegram, the quality of service of the capacitive coupling surface is sufficient for secure encoder-side data transmission. We call this process "sensitive intelligence." On this basis, an action-integrated identification can be redefined:

• 1. Intention of a user equipped with at least one encoder to perform an identifiable action (eg opening a locked door).
• 2. approach (eg by hand) to the coupling surface of a receiver, so that construction of an AC circuit; the feedback takes place via parasitic capacitances.
• 3. Receiver "recognizes" the irregular pilot tones
• 4. It generates a load telegram by impedance-changing the input stage in a random but meaningful rhythm.
• 5. The encoder decodes an instruction from the load telegram BT
• 6. Encrypts his identification data, and selects, for example, a transmission frequency, baud rate and transmission method (eg ASK, FSK, etc.) (s. 6 )
• 7. The encoder outputs the encrypted signals and then generates a pilot tone again
• 8. The receiver amplifies, decodes and decrypts the encoder signals
• 9. If a certain code sequence matches, a pulse is output, eg to open a shutter mechanism (possibly via a control unit).
• 10. At the next pilot tone, he gives the receiver an "OK" message and further information about a new load telegram.The load telegram may contain information originating from or caused by the code transmitter.
• 11. When the user leaves, the dialogue aborts. The encoder then only generates pilot tones and the receiver reports the distance (eg closing command).
• 12. In between, the transmitter and receiver constantly "investigate" your environment for faults.

By the irregular output of pilot tones Collisions should be largely avoided when using multiple encoders become. Here is the distance of the frequency output (burst) from a fixed and at least one random Time portion that do not exceed a certain duration may (so-called dirty burst).

Example of generating "dirty bursts" in the programming language "C", assuming that the encoder fulfills its functions by means of a microcontroller (or a similar logic):

Further exemplary applications

In addition to identifying information can be detected by sensors Transfer data to the receiver become. For example, in medical technology it is possible to have bioelectrical data (EEG, EMG, ECG, etc.) as well as pulse, temperature (s), respiration, pressures (blood, Swelling, etc.) and in the transmitter e.g. cache (Logger). When approaching to a receiver can this over the BT e.g. Select sensors or read the buffer (flush). The dealer can as one Art be designed electronic patch, which on a too examining body site is glued. The recipient can over his load telegram also stimulation (eg electrical stimuli) trigger. An impairment the patient by radio waves does not occur. The data transmission over the skin, not the body and its cells.

electrical firing weapons can user-dependent function (so-called Smartguns), if such a weapon with a receiver equipped is. In the load telegram also information about the ammunition content (e.g., by digitizing the spring tension of the magazine) and the usability be included. The weapon only works if the user has one authoritative donor. and holding the weapon in his own hands. This can cause accidents (e.g. with children) or abuse.

Another useful application could be that of an electronic ticket. In this case, the donor can store in a non-volatile memory data that provide information about, for example, the use (validity, price range, seat rank, etc.). When entering a chargeable institution (cinema, theater, sports or recreational facility, public transport, etc.) debits can be made via the debit telegram of a recipient attached to the entrance (eg with coupling foil in the floor), guiding information (eg Show seat etc.), or other information is transmitted.

The virtually unidirectional dialogue system is everywhere because comfortable and cost-effective where other wireless technologies (radio, transponder, IR light, etc.) were used, and either on a dialogue waived and / or only with considerable effort and / or security risks could be realized. A combination of different Technologies is possible e.g. to make it safer or more comfortable.

By an easy-to-implement rhythmic change in input impedance the recipient receives the donor Information. This is possible only in an AC circuit, such as it preferably arises in capacitive data transmission. A dialogue can take place because of the encoder with its frequent pilot signal the carrier for the Load telegram of the receiver provides what in principle represents an amplitude modulation. at constant output level, the pilot tone is not charged, but rather the rhythmic load in the parasitic feedback loop must be detected. This in turn makes unauthorized listening to the load telegram more difficult BT.

The Invention simplifies and reduces bidirectional data transmission systems and allow one action-integrated identification of a user. So that can the system prefers in "Personal Area Networks (PAN) are used. Besides, there may be existing technologies to complement comfort and / or safety factors.

Claims (23)

Method for processing a data transfer between a master system (encoder) and a slave system (receiver) Basis of capacitive interaction effects on which side of the master system a signal event in a reception area of Slavesystems is discharged into it and where by the master system a pilot sequence is emitted and during the input of the pilot sequence modulates the input impedance of the slave system in accordance with a data pattern becomes, whereby on the part of the master system the modulated change the input impedance of the slave system is detected and in which from the modulation pattern detected by the master system Input impedance of the slave system, a record is generated and this dataset is authoritative is for the information content or for the admissibility a continuation of the data transfer from the master system to the Slave system. Method according to claim 1, wherein in the area of the master system from the, from the modulated recording behavior of the slave system obtained signals are obtained on the basis of encryption the data transmitted further by the slave system takes place. Method according to claim 2, characterized in that that in the area of the slave system in the generation of the for the modulation the input impedance relevant data pattern is considered a time value. Method according to at least one of claims 1 to 3, wherein in the region of the slave system for the modulation of the input impedance Information content of the signals generated by the master system considered become. Method according to at least one of claims 1 to 4, wherein the modulation of the input impedance of the slave system under Recourse acquisition to an encryption procedure he follows. A method according to claim 5, wherein the part of Slave system for providing the modulation of the input impedance authoritative Data pattern consulted encryption procedure on the basis of information content on the part of the master system output signal sequence is configured or influenced. Method according to at least one of claims 1 to 6, whereby a congruence analysis initially takes place during the dialogue recording Based on a low encryption level, and that the encryption level subsequently is raised. The method of claim 7, wherein the raised encryption level authoritative Information content, at least initially at a lower encryption level be transported. Method according to at least one of claims 1 to 8, where about the master system is a signal sequence rated as an authorization identifier is selectively deliverable. Method according to at least one of claims 1 to 9, being over the signal due to impedance modulation of the slave system a configuration change of the master system developable is. Method according to at least one of claims 1 to 10, wherein the data transfer between the master system and the slave system for the settlement of a number, booking, value date or proof of receipt transaction is used. Method according to at least one of claims 1 to 11, wherein the data transfer between the master system and the slave system for carrying out a process for changing the locking state a motor vehicle is used. Method according to at least one of claims 1 to 12, wherein the data transfer between the master system and the slave system for the function release of equipment is used. Method according to at least one of claims 1 to 13, wherein the data transfer between the master system and the slave system to carry out a presence analysis is used. System for processing a data transfer with: one Master system component (encoder) and a slave system component (Receiver) in which the master system component is designed such that it is suitable is a signal event based on field-electrical interaction effects into a receiving area of the slave system component, and the slave system component is designed such that this makes it possible to define the reception receiving properties of the same modulated in which made arrangements in the area of the master system component are the changes to detect the reception characteristics of the slave system component and based on this detection, the further data transfer determine, the master system component continues to be so is designed that this from detected modulation patterns of Input impedance of the slave system generates a data record and this dataset is authoritative is for the information content or for the admissibility a continuation of the data transfer from the master system to the Slave system. Master system component for a system according to claim 15, which has a signal output device as the surface electrode is trained. The master system component of claim 16, wherein said an electronic signal processing device comprises. The master system component of claim 17, wherein the Signal processing device Access to a key data storage device Has. Master system component according to at least one of claims 15 to 18, these being taken in a check card-shaped body is. Master system component according to at least one of claims 15-19, which forms part of a vehicle key system. Slave system component for a system according to claim 15, which has a receiving device for receiving Input events based on capacitive interaction effects. The slave system component of claim 21, wherein said Receiving device in the area of a cash register system, a person passage area, a sales system or a device is arranged. A slave system component according to claim 21, which is part of a vehicle door locking system forms.