Method and apparatus for protecting reading device for data medium in form of card from unauthorised evaluation or copying of magnetically encoded data of data medium in form of card. RU patent 2504836.

FIELD: information technology.

SUBSTANCE: disclosed is a method of protecting the reading device for data medium in form of a card from unauthorised evaluation or copying of magnetically encoded data which are recorded on the reading device for the data medium in form of a card. A magnetic interference field is generated using an interference field coil. The arrangement of at least one interference field coil is such that an authorised magnetic reading head when reading magnetically encoded data on the data medium in form of a card is also under the effect of the interference field of the interference field coil. An output or resultant signal of the authorised magnetic reading head formed by the useful signal of the data medium in form of a card and the effect of the interference field is detected. The effect of the interference field of the interference field coil on the output or resultant signal of the authorised magnetic reading head is compensated for or filtered, or the useful signal is selectively filtered off from the output or resultant signal of the authorised magnetic reading head.

EFFECT: preventing unauthorised recording of magnetically encoded data on data media in form of a card in the zone of reading devices.

29 cl, 8 dwg

The invention relates to a method and device for the protection from unauthorized and discreet assessment, or copying of the information stored on data carriers in the form of a card, as outlined in paragraphs 1, 14, 24 and 26.

In particular, in connection with payment cards often happens that payment machines or similar machines service provision with necessary reading devices for such payment cards by unauthorized third parties with fraudulent intentions subjected to such manipulation, that in the case of justified the application of these machines bona fide user of the data recorded on the magnetic strip data carrier in the form of a card, quietly read with criminal intentions. With this purpose, for example, in front of the hole to enter magnetic card discreetly installed additional playback head, which then when the cart card invisibly logs data stored on it. These data are stored and then unlawfully used for the manufacture of copies of cards with identical data. The required PIN if required then usually when you type in the health service terminal is observed or recorded. This information is then fraudulently used by criminal elements in connection with the copy of the map.

Therefore, readers on payment machines are provided in some cases, positive measures in the field of nests card reader, in particular the speakers in front of a slot card reader, or costly and expensive control device, which hinder the successful placement together readers. These measures, however, only conditionally satisfactory.

In addition, DE 20 2005 021 134 U1 known execution, which in the area of holes for inserting the card reader of cards is generated magnetic the field, so that obstructing the registration card data through unlawfully established in this zone the read head. Therefore, the joint reading, recording and reproduction of the data does not lead to adequate and suitable for use copies of the original map. According to this well-known form of execution in the area of the input reader of cards placed a magnetic coil, which is powered from the corresponding generator frequency, so in the zone before receiving a hole card reader is formed magnetic field, which interfered illegally installed valves reading. The disadvantage of this famous implementation is primarily the fact that the magnetic the field of the coil creates interference not only valves reader installed with fraudulent purposes in front of the adoptive hole card reader, but proper valves actually read the card reader. In practice, this problem is solved by the fact that apply card readers with a relatively large constructive depth at which the read head inside the card reader properly removed from the entrance of the hole card reader. In addition, field is switched off as soon as you entered the card is fully seated in the card reader, and thus will be out of the registration of head reading, illegally installed externally on the reader cards. However, these measures are only possible to a limited choice of card readers with a sufficiently large constructive depth, in particular in cards in which this card is completely disappears in the output bore the reader, before the magnetic stripe of the card reaches the internal or good head read. First of all, in cards, preferred access systems, with a short constructive depth in which the internal or good read head is placed relatively close to the sink hole card reader, such solutions are not possible. In particular, readers by inserting cards or readers by pulling cards these measures are unsuccessful.

The present invention is the creation of methods and devices by which unauthorized registration of magnetically encoded data on the media data in the form of a map in area of readers for these data carrier can be prevented reliable manner and with a high degree of protection against manipulation.

Regardless of the objective of the invention is to create such an implementation, in which the influence of interfering field cannot be filtered simple means of output or total signal illegal head reading, performing joint reading.

Separately from the above-mentioned tasks independent objective of the invention is to propose measures that fraudulent manipulation in the near zone of a reader are reliably detected.

First called the objective of the invention is solved signs of paragraphs 1 or 14.

At that, preferably, operated, or employed in this method, the reader provides increased protection against fraudulent manipulations. Including field is no longer required to disable a service, while the magnetic storage medium is about internal or authorized magnetic read head of the reading device. In particular, field and during the phase of reading, contained on the media data, information or data may remain active, because the effect of interfering field at any point in time is compensated signal-technical way. Thus, the use of interfering electromagnetic fields are also possible in the case of readers with a relatively short constructive depth. In particular, the data carrier data can be read when the plot of the data carrier in the form of cards even speaks of a reader and, thus, there is illegally installed valves reading. This means that the invention countermeasures can be applied also in the case of readers with short automated by moving the media data in the form of the card readers by inserting cards or readers by pulling cards manual feed or relative positioning of the data carrier. Illegally installed read head at any relevant time intensive, field, and for illegally installed head read there is no possibility of signal technical compensation, so that the unauthorised registration, evaluation and copying relevant to the use of data reliably prevented.

Activities according to item 2 of the claims is preferable, that the useful signal with compensated obstacle, which is derived from the magnetic field of the media data in the form of a card is restored computing by or by digital signal processing, so that can be achieved especially fast and reliable or accurate reconstruction of the useful signal. Further, it is essential to using the signal-technical model can calculate the effect of interfering fields for each of arbitrary characteristic of interfering field or arbitrary and quasi-random characteristics of interfering control signal powering the coil of interfering field. Otherwise than in the application of periodic interfering signal according to the level of technology, the application of interfering signal control is impossible, exclusively from the signal of the illegally installed head reading, to reconstruct the components of the useful signal with compensated hindrance. Abolished then fraudulent manipulation and attempts to register, the more that will not generate relevant data or information cards.

At the expense of measures pursuant to paragraph 3 of the claims guaranteed that the effect of the interfering magnetic fields is also recognized in the output signal authorized magnetic read head, and you by this can be interpreted as the existence of the principle of interfering field, and its possible changes.

According to their preferred option for implementation in accordance with paragraph 4 of the claims is provided by the use stochastic, that is, a random control signal or field with random time characteristic. While the actual impact of periodic interfering signal illegally installed head reading relatively simply can re-filtered and thus free from interference alarm information can again be restored, this is not possible when using interfering control signal.

At the expense of measures pursuant to paragraph 5 of the claims practical way is generated control signal, which has strong stochastic properties. In this way, even by long-term registration of the signal received by illegally installed head reading, performing joint reading, which is formed by the additive superposition of interfering field and the payload, the longer have the applicable signals or information or data, and use their unlawful way to make a copy of the map.

At the expense of measures pursuant to paragraph 6 of the claims the possibility of using stochastic noise and interference control signals or interfering fields, and again to compensate for these based on the randomness of interfering influence exclusively by integral signal processing by the reading device. For or illegal magnetic heads reading takes place, on the contrary, mixed form of interfering field and magnetic field data carrier, and the division or Department of the corresponding signal components, without the knowledge of the process of change stochastic interfering signal cannot be carried out.

Due to the measures under paragraphs 7 or 8 of the claims is preferred that you can almost calculate in advance how it will look or change emitted control signal after the transfer on the plot transmission and after his recovery. Thus it is possible to generate any form of signal transfer on a site transfer and then calculate the components of the interfering signal, or effect of interfering signal control and reconstruct the useful signal, which corresponds to the signal, which had been registered without the influence of interfering field. In particular, due to the distortion of the signal in the output or total signal of the internal or proper magnetic head reading may be excluded, and if passed complex, in particular, stochastic interfering signals.

At the expense of measures pursuant to paragraph 9 of the claims can also be a particularly complex transmission characteristics. The essential is that the filter model can accurately be consistent with the transfer function, and that its output is thus almost the same signal that the output authorized magnetic head reading, or as the corresponding series of samples of the output subsequent analog-to-digital Converter, and if no media data in the form of a card not read, that is only field effects authorized magnetic read head. Therefore, by simple subtraction can remove signal from the total or total signal magnetic read head, and the remaining signal is further processed as the reconstructed signal.

At the expense of measures pursuant to paragraph 10 of the claims or any time there is no risk that are relevant to the use of signals or data carrier data will be recorded unlawful manner. In particular there is no time frame in which it would be possible to get practically net output signal from the data carrier magnetic-coded data. Due to this, fraud or illegal manipulation improves in a high degree.

At the expense of measures pursuant to paragraph 11 of the claims is preferred that a fraudulent manipulation or time-dependent or associated with ageing of defects can automatically recognized. The advantage of this solution, among other things, is that when the fraudulent adding, deleting, or changing magnetic and/or conductive parts in the zone of influence of the coil of interfering field magnetic lines of force and the transfer function of the coil of interfering field relative to the internal magnetic valves reading reader change. However, simultaneously with the signal-technical model is available comparative parameter for the initial or a specified state. This means that due to unlawfully placed in the zone of the reader or coil of interfering field, modified or deleted from this zone magnetic operating units, a previously defined signal technical model is consistent with real or actually manifested terms of transfer. This deviation, starting from a certain extent, can be evaluated as a sign of fraudulent manipulation, and a card reader or other peripheral unit, in particular them equipped with automatic, may be removed from operation, and, if necessary, can generate an alarm. Appropriate true in the case of a simple technical defect, which modifies the action or property transfer section. This may, for example, occur when modifying the characteristics of the coil of interfering field or authorized internal magnetic head read. Also with the help of these measures can automatically recognized technical defect magnetic head, reader reader, and may be issued an alert.

At the expense of measures pursuant to paragraph 13 of the claims is preferable that the reconstruction of the useful signal, the signal-based illegally installed magnetic head reading additionally difficult. In particular, these additional signal components of discernment or the selection by the signal processing of the signal, which originated from the data carrier can be difficult. Therefore, unauthorized attempts to register that during the processing of the registered signal aim to identify specific standard forms of signal, reliably prevented.

The task of the invention can be solved using the device according to paragraph 14 of the claims.

Benefits or outcomes for this device, is correlated, in essence, with the benefits or results of the events in the method according to paragraph 1, of the claims. In particular, this provides that the influence of the coil of interfering magnetic field on the read head of the card reader in any moment of time can be compensated for and thus only useful signal that comes from the entered data media in the form of a card can be extracted reliably. Due to this, you may receive comprehensive interfering magnetic fields, as well as more sophisticated noise and interference control signals and design more compact readers. Provided with particularly high degree of protection from manipulation or fraud equipped thus the reader may easiest way to be added to the existing readers. In particular possible, essentially without any problems upgrading or retrofitting existing readers. The inner authorized compensation of interfering field is especially functionally reliable and applicable also for complex or data-intensive signals, when this does not occur higher latencies or processing times.

At the expense of measures pursuant to paragraph 15 of the claims guaranteed, without knowledge of the characteristics of interfering control signal is no longer possible to allocate the actual signal. Thus, a pseudo-random control signal complicates the registration of the applicable useful information and addresses aimed at this unlawful interference. It may additionally complicated by repeated device, in particular, by duplicating a configuration coils of interfering fields with the corresponding linearly independent signals.

In a variant of the implementation of paragraph 16 of the claims is preferred that by limiting or concentration bandwidth of interfering control signal in a typical useful signal area, the total capacity of interfering control signal in relation to the action or efficiency in the frequency range of the useful signal can be reduced. Back this means that with a constant or a specific output power of interfering field can be achieved greater efficiency in the spectral range of the useful signal. Design stages of amplifiers, as well as designing a coil of interfering field can thus be counting on less power, so that, as a rule, provide the possibility for a more compact design and more energy-efficient mode of operation.

The embodiment under item 17 of the claims is preferred that a significant part of the signal processing is carried in digital form. In particular, through the processor signals calculated or created on the basis of the model signal is simply deducted from the total signal output or magnetic read head, and the rest of the useful signal or through a digital-to-analogue Converter is converted back into an analog signal and is available for further processing, or the assessment of the useful signal is done by the software already in the processor signals. Thus, it provides a cost-effective solution in General, or the corresponding generator the invention of interfering field is integrated in the control electronics, and evaluation of the card reader.

In a variant of the implementation of paragraph 18 of the claims effect of interfering fields with reasonable accuracy is precomputed. Implementation of the easiest way may be software and implemented with the help of a signal processor. This digital filter can be characterized by a set of filter coefficients, which can be determined by the exact course of changes in the frequency and phase filter. Also the preferred is that such a signal technical model through a simple reprogramming or re-calibration can simply and quickly respond to the changing ratio or legitimate changes or condition, and if necessary even in the process.

In a variant of the implementation of paragraph 20 of the claims is preferred that provides a set of supporting factors, which describes the transfer characteristic of the right, which is not subject to manipulation state of the reader. The filter coefficients of the model may be calibrated at least once configured in such a way that the transfer function of signal technical model corresponds to the real path of the signal through the coil of interfering field.

In a variant of the implementation of paragraph 21 of the claims is preferable that the saved settings models serve as a comparative values for the adoption of a decision on the presence of manipulation or defects reader. In this case, not remaining are not fully compensated signal is applied as a sign of manipulation or defect and deviation of the continuously or periodically calibrated model parameters relative to the initially defined and stored parameters is evaluated as an indicator of manipulation or defect. For example, this ensures automatic detection of fraudulent manipulation near the position of the read data carrier in the form of maps, in particular in the gaps for the input data carrier in the form of a card. So, for example, automatically recognized by the criminal attempts to bypass in the form of electromagnetic screens or displacement coil of interfering field, which should reduce or eliminate the impact of the coil of interfering field on unlawfully set the read head. Also due to this automatically detected defect or focused disabling the coil of interfering field.

In a variant of implementation, paragraph 22 of the claims creates multichannel field, due to which the opportunities to reengineer the useful signal according to the map of signal unlawfully placed the head reading even more reduced. In particular, this improves the protection against wrongful manipulation of such a reader.

In a variant of the implementation of paragraph 23 of the claims, at relatively low technological tolerance can be guaranteed to be quite a permanent transfer function and well replicated influence of interfering field. Because of this, signal technical model, which is provided to compensate for the effects of interfering fields, for all or many instances of readers can be performed in a uniform way. Thus, the initial adaptation or setting the parameters of the model can in many cases be unnecessary.

An implementation option under item 24 of the claims provides the reader, which provides special protection against manipulation and prevent fraudulent manipulation considerably.

By the preferred option of the implementation of paragraph 25 of the claims automatically prevents the fact that the media data in the form of a map from the proper owner or user is entered, if there are unusual or indicate manipulation of the situation. Especially due to this, you can avoid the fact that between the carrier of the data in the form of maps and unlawfully placed read head is relative movement.

Finally, running under paragraph 26 of the formula of the invention is preferred because it makes the machines providing banking services, such as ATM machines or for transfers of cash or access control systems that provide a high degree of protection against manipulation and fraud.

Benefits are also provided by additional measures in accordance with paragraph 27, as the expense of the protected data from the magnetic strip or any time not feature in reader and not be at the transfer to the upstream electronic unit so that they could intercepted or read by fraudulently installed electronic circuits or through modifications of the original hardware or software.

In addition, activities under paragraph 28 of the claims provide the advantage of relatively low cost hardware is achieved comprehensive protection from fraud or manipulation. In particular, the encrypts data from the magnetic strip in the same block as the compensation of interfering field. This is a relatively small, relatively well-protected from the very beginning of the area to which you can access with particularly high costs or only with special professional knowledge.

The invention further explained in more detail on the examples of implementation with reference to the drawings, which in highly simplified form schematically presented the following:

Figure 1 - approximate reader type of reader with input cards for media data in chart form, corresponding to the level of equipment;

Figure 2 - card reader on figure 1, in the state of manipulation with the fraudulent purposes, and such manipulations often remain unnoticed by a bona fide user of the device of reading;

Figure 3 - the device with the corresponding invention protected against fraud, in which a system is established with the fraudulent purposes additional read head figure 2 respectively;

Fig 4 - further development of scenarios according to figure 3, containing more than one coil of interfering field;

Figure 5 is a block diagram of the unit of signal processing that can used for realization of the invention;

6 - advanced signal processing unit, containing adaptive signal technical model;

Fig.7. - further development of signal processing, containing repetitive use of adaptive signal technical models and additional integral blocks assessment, and management interfaces and communications;

Fig.8 - technical further development of protected from fraud reader.

First, it should be noted that the described various forms of performance similar items are similar reference positions or similar designations of the component contained in the entire description of disclosure within the meaning can be transferred into equal parts with the same reference positions or similar designations components. Also adopted in the description of the indication of the position, such as top, bottom, sides and etc, are directly described and depicted, drawing, and they are changing the position is transferred by the sense and to the new location. Moreover, some of the signs or combinations and the multitude of signs shown and described various options for implementation may be of independent, relevant to the invention the solution.

Figure 1 shows the normal reader 1 for media 2 data in the form of a card, on which information or data to be written at least magnetically. In particular, the reader 1 holds capable of processing 3 magnetic cards with at least one magnetic stripe 4 and/or smart cards with at least one magnetic stripe 4. This magnetic stripe 4 saved, as it is known, relevant to the use or protection of data that can be read in automatically by the reading device 1 and/or may be changed or updated. In the case of such magnetic media 2 data in the form of a card is usually referred, in particular, the Bank or payment cards, as well as the maps, certifying powers, for authentication of the right to access or use certain devices. That is, the specified reader 1 is often used in banking or other machines the provision of services or access control systems.

Such readers 1 usually have the following components: building 5, at least one device 6 input or receiver card reader for submission and subsequent reception of the magnetic media 2 data, at least one transport rollers 7, 7' with motor drive for automatic retracting and pull filed media 2 data, if necessary rollers 8, 8' back-pressure and/or guiding elements 9, at least one magnetic head 10 reading touch Desk stored on the media 2 data magnetically coded information and diagram 11 assessment and management relevant for the scanning process, the functions of the reader device 1, and to decode the signal, received from the magnetic head 10 read and/or set of clamping elements for contact with a chip card and/or contactless reader box, or RFID. Figure 11 assessment and management is, for the most part, also for transformation of received signals to the appropriate digital information and to make this information available through appropriate interface 12 signals or data. Interface data may represent an interface for bidirectional communication, such as the serial interface (RS 232, RS 485, Ethernet or USB interface. Interface 12 signals or data may consist of one or more lines 13 States or signals through which signaled a certain state. For example, this line 13 States or signals can be provided to unlock the front door, if you entered media 2 data is recognized as a valid and eligible.

In the image of figure 1 is a schematic representation of magnetic cards reader, which partially implemented magnetic card 3 magnetic stripe 4. Figure 11 assessment and management for greater clarity presents outside of the hull reader 5 1. However, the scheme 11 assessment and management, as a rule, together with the mechanical and electrical components is integrated into the housing reader 5 1.

Other commonly available, but not necessarily required to represent the ideas of the invention of the mechanical, electrical, and Electromechanical components card reader, such as, for example, lockable valve or damper on the receiving hole card reader, spring-loaded elements pressing and guiding elements, the source of the supply voltage sensors to identify and define the position entered media 2 data, memory elements for the conservation and call data and programs via the CPU, DSP CPU), as well as various signal-technical relations, for illustrative purposes, are not represented in the drawings. In addition, these items are well known in the art and may be without any problems implemented.

Figure 2 shows the reader 1, in particular regular reader of magnetic cards, as in figure 1, in which, however, the criminal element prior to actually receiving hole card reader, or in front of the hole 6 input for media 2 data in the form of a card with the fraudulent purposes an additional magnetic head 14 read in such a way that when applying a magnetic card 3 information on the or data together to read and can be used for further fraudulent playback similar according to a magnetic card. Due to the generally very compact and disguised constructive implementation of additional magnetic read head is usually not recognized, and unauthorized registration card information may be unobservable for the lawful owner of the card.

Signal additionally placed by fraudulent purposes magnetic head 14 read, as it is known, that later illegally logged criminal elements using secretly located recording instrument 15. Then the resulting data can fraudulently be used to make unauthorized copies of maps.

Figure 3 shows the corresponding invention reader 1, in particular magnetic card reader with relevant invention of a device to protect against fraud or relevant to the invention generator 16 interfering field. On the inner side of the suction reader or holes 6 input installed on at least one magnetic current coil 17 interfering fields that are loaded preferably stochastic control signal. Preferably stochastic control signal produces the coil 17 interfering magnetic fields field 18, which also affects placed before adoptive hole with fraudulent purposes magnetic head 14 read and induces in it signal that the additive is superimposed on the signal, which arises due to moving past the magnetic card 3. Due to this overlay the useful signal cards stochastic interfering control signal generator 16 interfering field or interfering field them coils 17 interfering field prevents the registration of the actual map data and unauthorized duplication of the data card. In addition, field 18 similarly acts on the actually relevant for the work of the magnetic head 10 reading reader 1. In particular field coil 18 17 interfering field can be quite intense, or coil 17 interfering fields and which is authorized or proper magnetic head 10 reading can be positioned so close together that field 18 accordingly affects the magnetic head 10 read and influence its signal mode or the result of the reading.

Coil 17 interfering fields, figure 3 shows how placed inside the reception of the hole card reader or within the housing 5. However coil 17 interfering field can, in principle, also be positioned before receiving a hole card reader that is outside their own card reader. The coil 17 interfering field can be performed according to the type of the additional module.

It is essential that the positioning of the coil 17 interfering field and/or the choice of capacity of radiation, in particular the field strength or the characteristics of radiation, in particular characteristics of the field coil 17 interfering field, or select the receive sensitivity authorized appropriate proper magnetic head 10 reading is that the field coil 18 17 interfering field at least during scanning magnetic encoded data carrier 2 data affects hosted by fraudulent purposes magnetic head 14 reading, as well as enabling the appropriate authorized magnetic head 10 read and influence its output or total signal.

Generator 16 interfering field are presented as a separate building block, which is the preferred way can be run as an optional or additional or secondary module to normal, the existing scheme, 11 assessment and management for the reader 1. First of all, in new construction readers 1 generator 16 interfering field can constitute an integral constituent part of the control electronics, in particular schema 11 assessment and management.

Processing of the signal generator 16 interfering field is implemented as a digital system for the taking of samples with analog-digital and converters 19-19' on transitions to analog signals. For approval of the appropriate level of analogue inputs and outputs analog-to-digital and digital-to-analogue converters 19-19' provided cascades 20-20' amplifier and coordination, which usually include low pass filter (the filter of the noise suppression overlay) etc. In addition, the scheme of the generator 16 interfering field contains digital computing unit, preferably digital block signal processor 21 (DSP), which with a magnetic head 10 reading reader 1, coil 17 interfering field reader 1 and with scheme 11 assessment and management of the reading device 1 is conductive. Alternatively, this electronics assessment can be implemented, at least partially, through block signal processor 21, as described in more detail below.

Generator 16 interfering field powered electric coil 17 interfering field stochastic control signal, due to what is generated stochastic field 18. Electric output or total signal of the magnetic head 10 reading reader 1, which also affects field 18, when this is not directly on the electronics of the evaluation, that is, not directly on the chart 11 assessment and management of the reading device 1, and the first on the DSP unit 21 generator 16 interfering field that calculates or filters out all signal components, correlated with control signal. Adjusted unit signal processor 21 or exempt from interference signal, i.e. the useful signal chart 11 assessment and management and is estimated in the usual way. Alternatively, it would also be possible to estimate released from jamming signal, i.e. the useful signal is made through a block signal processor 21 and the latter used to control processes reader 1 or peripherals, as explained below.

Binding reader 1 to the superior management instruments, such as the management of payment machines, the drawings shown is only a simplistic way, namely as a common interface to 12 signals or data transmission or routing information from magnetic card 3. Actually receiver data for illustrative purposes only, is not presented.

Generator 16 interfering fields can also have different control inputs and control outputs. For example, generator 16 interfering field may include the input or output interfaces for managed activate and deactivate interfering field of 18, to initiate the initial calibration together with the subsequent preservation of the coefficients in the model signal transmission or behavior of the signal, to initiate the reset hardware and/or to signal an unacceptably large variances between the saved signal model (desired state) and actually arising ratios (actual status). The last named interface generator 16 interfering field could also give an indication of the unauthorized manipulation of the reading device 1.

The functionality described inputs and outputs can, of course, be provided through a more complex communication interface, which is provided for connection with the higher a Manager of a calculator. This is a more complicated interface can be made, for example, as a serial interface RS 232 or RS 485, Ethernet interface or USB interface.

In addition, there generator 16 interfering field is made as an integral component of the Central figure 11, evaluation and control reader 1. In this case, output or total signal of the good or authorized magnetic head 10 reading in the digital block signal processor 21 exempt from interference, that is extracted components, correlated with both signals. Accordingly exempt from interference with the signal, that is, the reconstructed signal magnetic head 10 read, then directly decoded digital block signal processor 21, and extracted data is routed in senior management tool devices, in particular, through the interface 12 signals and data. Digital block signal processor 21 accepts in this case, the drive control conveyor rollers 7, 7' reader 1, as well as manage existing, if necessary, are not shown for reasons of clarity components such as a controlled flap to the receiving of the hole card reader, or an assessment of various sensors to determine the position of the imposed magnetic card 2.

Figure 5 shows in the form of a flowchart implemented in the digital block signal processor 21 digital signal processing for a relatively simple form generator 16 interfering fields, for example, for realization of the invention by the reading device 1 on figure 3.

The starting point for the formation of stochastic control signal is digital generator 23 pseudorandom numbers. This generator generates at least pseudo-random numbers. Produced by the generator 23 pseudo-random number sequence of random numbers corresponds to at least approximately, white noise with at least uniform spectral power density in the whole discrete frequency range of digital system of taking samples.

The preferred way the sequence of white noise generator 23 pseudorandom numbers through a digital band-pass filter 24 limited bandwidth, which typically includes at least the part of those frequencies that occur in the useful signal magnetic head 10 read when reading magnetic card 3 (figure 3). Power or bandwidth of interfering control signal focuses thereby on those frequencies, which are essential for the distortion of the signal outside or fraudulent magnetic valves read 14 (3) and who also may not be excluded simple band-pass filter without removing thereby constituting a useful signal. Limited by the bandwidth of the output sequence is served on not shown analogue Converter and converts the analog the control signal for the coil control 17 interfering field (figure 3).

Besides, the same sequence of random numbers generator 23 pseudorandom numbers or as a dotted lines, signal output bandpass filter 24 is served on the signal-technical model 25, in particular, digital filter model 25A. Digital filter 25A model here presented formally as FIR filter in normal form. Design, implementation and properties of such a FIR filter is described in the relevant literature relating to this area. The filter coefficients 25A model is chosen so that thereby all the transfer function of the real sector from the generator 23 pseudorandom numbers through a band-pass filter 24, coil 17 interfering field and a magnetic head 10 readout displays the signal-technical way. The preferred way the filter coefficients 25A models describe the signal transfer characteristic only of the transmission path between the generator 23 pseudo-random numbers and provided a fictitious point 26 summation, which is made between the signal of the coil 10 of the magnetic field (Fig 3) and the output signal digital filter model 25A. The coefficients of the digital filter model 25A characterize thus the signal transfer characteristic of the area between the generator 23 pseudorandom numbers, band-pass filter 245 and presented on figure 3 for an example elements: Converter 19', cascade 20' amplifier or approval coil 17 interfering field, a magnetic head 10 read, waterfall 20 amplifier or approval and analog-to-digital Converter 19 back to point 26 summation. As mentioned above, this section of signal transmission between the generator 23 pseudorandom numbers and returnable tract 27, which,based on the magnetic head read 10 (3), passes to the point 26 summation, also host the other components that define the signal transfer characteristic or affecting the. Other factors of influence on this area of signal transmission are best displayed with the help of coefficients of the filter or filter model 25A. The essential thing is that through the filter coefficients is formed signal technical model 25, which quite accurately reflects actual signal transfer characteristic for the above plot of signal transmission. In this simple form generator 16 interfering field is provided by the one-time and fixed determination of the coefficients of the filter, in particular, in the factory. Determination of the coefficients of the filter may, in particular, already in the factory carried out after assembling all of the reading device 1 and, for example, introduced through the calibration process.

In point 26 summation calculated sequence influence of interfering field is subtracted from the real output or total signal of the magnetic head 10 reading of it digitized sequence of discrete values. A real signal of a magnetic head read 10 (3) through a symbolic return path 27 is served in point 26 summation. In point 26 summation then component in the output or total signal of the magnetic head 10 reading is eliminated, and thus contains no interference or exempt from interference signal is reconstructed for further processing. This interference-free signal is available in the tract total of 28 points 26 summation.

The above processes or connection should be understood as a model. Their implementation is managed software programmable block signal processor 21. In particular, the above signal technical model 25 is implemented via the signal processor 21.

Fig.6 shows the expanded version of the signal processing generator 16 interfering field, which in contrast to the basic version according to figure 5, an additional or permanent and/or activated by the needs of adaptation filter 25A model to a real transfer characteristic. Therefore, in the software signal processor implemented the corresponding algorithm 28 adaptation. Known algorithm 28 adaptation is called an algorithm of least medium-sized squares (LMS) (see, for example, work Widrow Stearns). Adaptation can be performed in the time domain, and with the use of fast Fourier transform (FFT) in the frequency domain.

Fig.7 shows further improved version of the signal processing generator 16 interfering field signal technical model of 25, especially for the reader device 1 on figure 4. In contrast option on 6 there are formed two uncorrelated sequence interfering signals for the control of two coils 17, 22 interfering fields (figure 4). Thus, there emerges field. For each of the two interfering channels provided individual filter 25A, 25' model, which simulates the impact of the relevant interfering signal is on the magnetic head 10 reading reader 1. Filters 25A, 25' model may 6, be adaptive, and thus consistent with the permanently changing transfer functions. Accordingly duplicate go repeatedly implemented functional elements or components of the keypad signal processor 21 are marked with the corresponding reference positions with an optional apostrophe.

Additionally according to Fig.7 also performs decoding of the useful signal from proper magnetic head 10 reading from the reader device 1 by means of the keypad signal processor 21. To do so, in the signal processor 21 is based on the software of the unit 31 evaluation. According to the block diagram on Fig.7 is, in addition, the drive control device for transportation card reader 1 (figure 4) via the signal processor 21, in particular through implemented in it management 32 drive. In addition, at least stored magnetically map data, in particular, at least relevant or necessary part of these data are available through the corresponding interface 33 parent controls devices.

Next to the forms of execution on 3-7 describes the preferred event method or procedure for functioning of the invention. These describe the way or structures related to the invention, can be transferred to different forms of execution on the same parts with the same reference positions.

In accordance with the above examples execution is also built generator 16 interfering field, which interacts to or associated with the signal-technical model 25. Using this signal technical model 25 signal transfer function, proceeding from the coil 17 interfering field, shown or described in relation to an internal magnetic valves 10 reading reader 1. Using alarm-technical model 25 calculates the effect of interfering field 18 of the output signal of a magnetic head 10 read or characteristic of interfering field 18. In particular output or total signal of the magnetic head 10 read, which is composed of the useful signal carrier 2 data in the form of a card and of interfering control signal or interfering field of 18, is adjusted by subtracting the calculated impact of interfering field. The impact of the interfering field of 18 on the magnetic head 10 read fully or almost fully compensated. After subtracting the calculated impact of interfering fields remaining signal or useful signal contains only those elements that are formed by moving past the magnetic head 10 magnetic strip reading 4 magnetic card 3. That is computed signal corresponds to the useful signal, as if he was checking in without additional impact of interfering field 18.

Signal-technical model 25 for preliminary calculations of the influence of interfering field preferred way is implemented through a digital filter 25A or 25' model, which, in particular, can be formed by FIR filter. Digital filter 25A or 25' models may be performed programmatically-technically and implemented block signal processor 21. Such a filter 25A, 25' model has a set of filter coefficients, by which the frequency and phase response of the filter can fairly accurately set. FIR filter (finite impulse response) preferably formed implemented in digital form filter. In principle it would be possible to implement a suitable signal technical model of the 25 in analogue devices and apply for carrying out the invention. That is the essential part of the described signal processing can be performed in analog technology.

The above events provide a number of substantial improvements and these activities are the starting point for many of preferred options for implementation: first, field 18 should not be disabled, while the magnetic card 3 passes by internal or authorized magnetic head 10 reading reader 1, then the impact of the interfering field of 18 at any time signal technically compensated, and not containing useful signal interference due to data from the magnetic strip is restored by calculations. Thus it is possible to use the interfering magnetic fields 18 and in case readers 1 short constructive depth - in respect of an input device, magnetic card 3. That is described generator 16 interfering field may be applied readers 1, in which the map data already read, while part of the magnetic card 3 more acts of a reading device 1, and thus still be available for the installed with the fraudulent purposes or with the objectives of espionage magnetic head 14 read. Generator 16 interfering field can also be implemented in the case of readers 1 with a short depth and constructive be permanently activated or activated during scanning magnetic data-encoded magnetic card 3. Thus installed with the fraudulent purposes magnetic head 14 read in any relevant point in time is loaded with a field of 18, and there is no possibility of signal technical interference compensation component of the output signal installed with the fraudulent purposes magnetic head 14 read.

Using alarm-technical model 25 the effect of interfering fields for each of arbitrary characteristic actions interfering field of 18 or for each characteristic of the interfering signal control powering the coil 17 interfering field of 18, can be computed. In contrast to the known from the prior art implementation, which uses a generator of interfering field, which produces a periodic signal in the case of the invention can also be used stochastic, that is, a random control signal or field 18. While the influence of periodic interfering signal is on the set with the fraudulent purposes magnetic head 14 reading can be quite easily filtered and thus may be restored not containing interference signal information, the application of accidental interfering control signal is no longer possible from the signal of the installed optional or with the purposes of espionage magnetic head 14 read reconstruct not contain interference signal components or the components of the useful signal.

To monitor the functioning and status of interfering field of 18, alternatively, the output signal of a magnetic head 10 reading can also be applied signal from not shown touch the coil, which is possible only with the purpose of control of interfering field of 18 or otherwise does not register any other useful signal. The establishment is not subjected to manipulation of the initial condition and the likelihood of subsequent manipulation is then in a similar manner as in the case of an output or total signal of the magnetic head 10 read, but without further processing of the reconstructed useful signal.

Forms of performance and representation in this document belong mainly to the reading devices type 1 for the readers with the input, that is, to the reading devices 1 motor-driven self-retracting and transportation carried out magnetic card 3. Invention is valid, however, and to various other applicable constructive forms of readers, magnetic stripe cards, as, for example, for hand-held readers with the holding of the card or the simple with inset maps.

Preferred embodiment, the further development of the embodiments of the invention described below. Preferred, among other things, is the implementation of these measures through a block signal processor 21. Using such a block signal processor 21 may, among other things, calculated broadband stochastic, in particular pseudo control signal. The preferred way control signal is painted a noise or filtered band-pass filter and therefore spectral limited noise, which respectively representation in figure 5 first is generated using a generator 23 pseudorandom numbers and filtered using a bandpass filter 24 and accordingly views on figure 3 is issued through a digital to analog Converter 19' and cascade 20' amplifier or approval for coil control 17 interfering field. In addition, output or total signal of the magnetic head 10 read, subjected to the influence of interfering control signal or interfering field of 18, is served through a cascade of 20 amplifier or approval of the analog-to-digital Converter 19 and then the kernel signal processor unit signal processor 21. In the block signal processor 21 simulated signal technical model 25 (figure 5, 6, 7) for the above plot in the form of digital filter model 25A, for example, type FIR filter. Filter 25A model displays its output in the same or almost the same signal sequence, as it gives an analog-to-digital Converter 19 (3) as a result of the output signal of a magnetic head 10 reading if no magnetic card 3 is not loaded, and only field 18 affects the magnetic head 10 reading. In the block signal processor 21 computed signal is subtracted from the total signal output or the magnetic head 10 read, and the residual or the resulting signal or via a digital / analogue Converter 19” (figure 3) is converted back into an analog signal and served on a chart 11 assessment and management to decode the data map (figure 3), or it decoding is already in the block signal processor 21 using the appropriate algorithms and software modules (figure 4). It is essential that the effect of interfering field coil 18 17 interfering fields on the output or total signal of the magnetic head 10 read offset or filtered, or is selective useful signal from the output or total signal authorized magnetic head 10 reading. Assessment or further processing of the useful signal can be accessed from inside reader 1 or peripheral electronic blocks.

For this generator 16 interfering field includes the signal-technical model of 25, which is designed to simulate the effects of interfering field 18 of the output or total signal of the authorized magnetic head 10 reading. This simulation is to offset the impact of interfering field 18 of the output or total signal of the authorized magnetic head 10 read, thereby, for the reconstruction of the useful signal dependent entered media 2 data in the form of a card of output or total signal authorized magnetic head 10 reading.

Is favourable, if the sampling frequency and frequency processing of the above discrete system of taking of samples or signal processing twice the maximum frequency components of the useful signal in the signal magnetic head 10 read when reading the magnetic media 2 data. Thus, it provides a full and unequivocal definition of the information contained in the useful signal.

Is preferred if the filter 25A model is made adaptive, and in block signal processor 21 algorithms or software modules, by which the filter coefficients for the filter model 25A at least once during calibration automatically aligned in such a way that the transfer function or mode of action of signal-technical model 25 corresponds to the transfer characteristic of the real tract signal through the coil 17 interfering field. Defined in the method of calibration coefficients of the filter preferably stored non-volatile manner ZU 30 (6), so that when you run the generator 16 interfering field re-calibration process becomes unnecessary. Besides, due to the preservation of filter coefficients with a set of supporting factors, which describes the transfer characteristic of the original and is not subject to manipulation status reader 1. To determine the appropriate filter coefficients suitable different, partly well-known algorithms and methods according to the level of equipment, for example LMS-algorithms.

Due to the individual instrument for adaptation of the filter model 25A becomes unnecessary to use fixed or permanently remaining the same signal-technical model 25 for all instances of devices or all readers 1. By this individual devices for adaptation of the mode of action of signal technical model 25 the preferred way, you can avoid or at least greatly reduce the problems in the current work, reader 1, especially due to tolerances of the components and manufacturing, as well as the changing influences due to variable situations installation.

Preferred is, if the digital filter model 25A also after the initial process calibration further adapted with a reduced speed of adaptation, that is, the filter coefficients signal technical model 25 configured on slowly changing the transfer characteristic. Without interventions for manipulating minor changes may occur in the transfer characteristic, for example, due caused by temperature or aging changes in the settings of the components. Through a continuous adaptation of the filter model 25A guaranteed that the influence of interfering field on the magnetic head 10 reading reader 1 and with minor changes in transfer characteristics offset by an optimal way. Despite the continuous or periodic adaptation, is preferable to provide an initial calibration, in which the parameters of the model for the transfer characteristic of the original state of the device are specified and saved volatile way. These saved parameters of the model are, on the one hand, as initial values at power for the signal and technical model 25, so that the compensation of interfering field works quite well and immediately after inclusion reader 1. On the other hand, the saved parameters of the model can serve as a comparative values for decision-making on the availability of manipulation or defects reader 1. In this case, as a sign of recognition for manipulation or defect preferably applied not the remaining are not fully refundable signal, and the deviation of the continuously calibrated model parameters in relation to the initially defined and stored parameters of the model.

In accordance with the preferred implementation provides that the adjusted on the effect of interfering field output signal authorized magnetic head 10 read those phases where no magnetic carrier 2 data is not inserted in the card reader 1, monitored to determine, exceeded a certain full or spectral output. And if so, then the corresponding status information or errors shall be available to the parent controls the device, if it is an indicator interventions to be manipulated.

According preferred to the further development, stochastic control signal additionally superimposed deterministic signal component. This deterministic signal component is similar to the essential properties of the useful signal when reading magnetic card 3. However, the deterministic signal component does not represent any valid data. Due to this event additionally hampered reconstruction of disturbance-free signal or determination of the useful signal from the signal established for manipulation of magnetic heads 14 read. This additional signal component can also contain variables, in particular, random characteristics that make it more difficult for discernment, or performed the technical methods of signal processing separation from any of the signal that comes from the magnetic card 3.

The preferred execution according to figure 4 provides for the application of at least one additional coil 22 interfering field, which at the place of dissociated from the first coil 17 interfering field, or his orientation of the magnetic field oriented with the deviation, or on its geometry of the magnetic field is done with a deviation. This second coil 22 interfering field is operated on the second, also stochastic control signal, which linearly independent from interfering signal for the first coil 17 interfering field. This means that the interfering signals for different coils 17, 22 interfering fields are not correlated with each other. The most popular way is formed multi-channel field 18, due to what the opportunity again to reconstruct from the noisy signal established for manipulation of magnetic heads 14 read relevant useful signal representing the data card, even more reduced, due to which protection against manipulation again improves.

According preferred the further development of the above device for fraud protection reader 1 or equipped with them the machine can run for automatic locking holes 6 input reader 1, if you installed the manipulation generator 16 interfering field is not functioning, or a section of the signal processing device for protection from fraud is inactive.

If the foregoing description on «signals» was considered in the context of the digital system of the taking of samples, i.e. in respect of the keypad signal processor 21, below is the first case of a sequence of digital sample values.

On Fig.8 shows the preferred further development reader 1 or device for protection from fraud, and for already described parts used the same reference position and the previous description of the meaning can be transferred to similar parts with the same reference positions. View on Fig.8 shows the technical development of performance according to figure 4, and, of course, also possible to apply this development for the variant of a running figure 3.

Accordingly preferred the further development of the reconstructed signal inside reader 1 or by using the device 11 assessment and management is encrypted. This is normal algorithm 34 encryption or decryption for information and technical encryption and/or decryption of signals or data. As a suitable way encryption and decryption can be used, for example, DES, TripleDES, RSA etc.

Accordingly encrypted signal, which is based on magnetically encoded data entered media 2 data then available or transmitted through the interface 12 data or through at least one line 13 status or signal to the upstream or peripheral electronic unit, for example, to a machine for the provision of services. In such authorized electronic unit, you decrypt the received encrypted signal through adequate algorithm 35 encryption or decryption, which can then be estimated or further processing of the useful signal, this data.

It is appropriate, if the encryption is useful signal from the carrier of 3 data, this data is undertaken by means of block 21 signal processor, which in addition is made with the ability to compensate or eliminate the influence of interfering coil field 17 of interfering field. Similarly, decryption is preferably through evaluation unit peripheral unit, which is normally formed by an industrial PC with appropriate software.

Similarly, when writing data on the magnetic stripe 4 may be encryption algorithm by 35 encryption or decryption in the industrial PC and decryption algorithm by 34 encryption or decryption device 11 assessment and management, in particular, by means of the keypad signal processor 21.

Due to this the preferred further development even in the case when made interference with the objectives of manipulation inside reader 1, longer have the applicable useful signals or data media 2 data. Using the above activities can be in many cases refuse relatively reliable and expensive placement in the case of the reading device for the protection from unlawful manipulation. To be protected, relevant to the security of the region is bounded by a chip or a smaller area of some zones inside reader 1. It provides, in the relevant guarantee against the risk, comprehensive protection against fraud or manipulation at relatively low cost.

The task which lies in the basis of independent, relevant to the invention solutions can be understood from the description.

First of all, separate shown in figure 3, 4, 5, 6, 7, 8 variants of implementation may be the subject of independent relevant to the invention solutions. Relating to the invention of tasks and decisions follow from the detailed descriptions of these drawings.

List of signs reference position

2 the data carrier in the form of a card

3 magnetic card

4 magnetic stripe

6 hole input

7,7' transport rollers

8,8' back-pressure rollers

10 magnetic read head (authorized)

11 a framework for the assessment and management

12 interface signals and data

13 line status or signal

14 magnetic read head (rogue)

15 recording device

16 generator of interfering field

17 coil interfering field

18 field

19-19” analog to digital/digital to analog converters

20-20” stage of the amplifier or approval

21 digital block signal processor

22 coil of interfering field (second)

23 pseudorandom-number generator

24 bandpass filter

25 signal technical model

25A,25' filter model (digital)

26 point of summation

27 the return path

28 the algorithm of adaptation

29 management line

30 of the law of Ukraine

31 assessment unit

32 drive control

33 Interface

34 algorithm for encryption or decryption

35 the decryption algorithm and encryption.

1. Way to protect reader (1) for the media data in the form of a card from unauthorized assessment, or copy magnetically encoded data recorded on the reading device (1) medium (2) data in the form of a card, and through the coil (17) of interfering field, which is located in near zone holes (6) input input media (2) the data in chart form or in a zone of good or authorized magnetic head (10) reading the reader (1), formed magnetic field (18)to use this field to interfere with or to impact on the set, the circumstances with spyware or fraudulent purposes magnetic head (14) read the magnetic field of the media (2) the data in chart form, characterized in that implement or post at least one spool (17) of interfering fields such that authorized magnetic head (10) readings when reading of magnetically encoded data carrier (2) data in the form of card also has the effect of interfering field (18) coil (17) of interfering field, register educated useful signal carrier (2) data in the form of a card and the influence of interfering field (18) output or total signal of the authorized magnetic head (10) reading, compensate or filtered influence of interfering field (18) coil (17) of interfering field in the output or total signal authorized magnetic head (10) read or selectively allocate filtering useful signal from the output or total signal authorized magnetic head (10) read, evaluate or further process the useful signal to the reading device (1) or in peripheral electronic blocks.

2. The method according to claim 1, characterized estimated compensation of interfering influence of interfering field (18) with respect to the output or by the total signal authorized magnetic head (10) read through the block signal processor (21), and with the help of a block signal processor (21) including realize signal technical model (25), through which displays the influence of interfering control signal in relation to the generated them field (18) on the output or total signal of the authorized magnetic head (10) reading.

3. The method according to claim 1, characterized positioning of the coil (17) of interfering field and/or choice of the field strength or the characteristics of the field coil (17) of interfering field and/or selecting a receive sensitivity authorized appropriate proper magnetic head (10) read in such a way that field (18) coil (17) of interfering field at least during scanning magnetic encoded data carrier (2) data in the form of a card has impact on the set with the fraudulent purposes magnetic head (14) reads and also affects the lawful appropriate authorized magnetic head (10) reading and affects its output or total signal.

7. The method according to claim 1, wherein the definition of the transfer characteristic of the transmission path, on the basis of the emitted interfering control signal to the registered output or total signal authorized magnetic valves (10) reading, and using a specific transfer characteristics to offset the impact of interfering field (18).

8. The method according to claim 1, wherein the definition of discrete transfer characteristics of the transmission path from a sequence of samples, corresponding to the initial light control signal to a sequence of samples that are relevant to the adopted output signal authorized magnetic valves (10) reading, and using a specific transfer characteristic for the payment of compensation of the influence of interfering field (18).

9. The method according to item 8, wherein the displaying of the transfer characteristic of the transmission path of the digital filter (25A) model, which is described by a set of numerical filter coefficients.

10. The method according to claim 1, characterized by formation of interfering field (18) at the time of registration of magnetically encoded data carrier (2) data in the form of card magnetic head (10) reading.

11. The method according to claim 1, characterized in that the output signal of an authorized magnetic head (10) reading, adjusted on the effect of interfering field (18), on those phases where no media (2) data in the form of a card is not inserted into the reader (1)controlled by the fact exceeded a certain full or spectral capacity, and if so, on his tool control devices provided with relevant information about the status or error message.

12. The method of claim 9, wherein the digital filter (25A) model in the current operating mode either permanently or with repeated at intervals consistent with the actual transfer function of the real plot of signal transmission, which contains at least coil (17) of interfering field and a magnetic head (10) reading from the reader device (1).

13. The method of claim 2, characterized in that the control signal at least at times imposed additional control signal, which is essentially similar to the properties of the signal that is received as a useful signal when reading the magnetic stripe data carrier in the form of a map of the magnetic head (10) reading.

14. The method according to claim 1, characterized encryption useful signal relative to its data the reading device (1), routing encrypted useful signal or data and decryption of the useful signal or data in the authorized peripherally located electronic unit.

15. The method according to paragraph 14, different encryption of the useful signal or data via the signal processor (21), which, moreover, made with the possibility of compensation or eliminate the influence of interfering field (18) coil (17) of interfering field.

16. Device fraud protection for application with the reading device (1) for authorized registration information stored magnetically on the media (2) data in the form of a card reader (1) contains the first appropriate authorized magnetic head (10) reader to scan the media (2) the data in chart form, and schema (11) assessment and management for the evaluation of the output signal authorized magnetic head (10) read and to convert the information contained in the output signal, the digital data set, with the generator (16) of interfering field, which forms field (18), which provided for interfering impact on established under the circumstances, in the near zone of the reader (1) with fraudulent purposes second relevant unauthorized magnetic head (14) reading, wherein the generator (16) of interfering field contains the signal-technical model (25), which is made with the possibility of modeling the impact of interfering field (18) on the output or total signal of the authorized magnetic head (10) reading, and this modeling is carried out with the possibility of compensation of the influence of interfering field (18) on a weekend or total signal of the authorized magnetic head (10) reading and thereby reverse engineering dependent entered media (2) data in the form of a card of the useful signal from the output or total signal authorized magnetic head (10) reading.

17. The device is protected from fraud by item 16, wherein the generator (16) of interfering field contains at least one spool (17) of interfering field, which is positioned in the near zone holes (6) entry for the media (2) data in the form of a card, and is powered non-recurring charge stochastic, especially pseudo-random, control signal.

19. The device is protected from fraud by item 16, wherein the essential parts for signal processing, in particular signal technical model (25) to offset the impact of interfering fields, formed a discrete system of taking samples, which includes at least the processor, in particular the DSP unit (21), analog-to-digital Converter (19) and digital to analog Converter (19').

20. The device is protected from fraud by item 16, wherein the signal-technical model (25) formed digital filter (25A) models, particularly FIR filter.

21. The device is protected from fraud by item 16, wherein the generator (16) of interfering field contains a non-volatile memory to save at least one set of filter's parameters of digital filter (25A) model.

22. The device is protected from fraud by item 21, wherein at least one set filter parameters specifies the filter (25A) model, which simulates the transfer characteristic for the emitted by jamming coil (17) and then re-registered authorized magnetic head (10) reading of interfering control signal in not manipulation fully operational condition of the reading device (1).

23. The device is protected from fraud by article 22, wherein the filter (25A) model while you work continuously or at regular intervals and continuously adapts consistent with the changing of the transfer characteristic of the real site, and at least one set of stored settings of the filter at least re is compared with a set filter parameters for the adaptive filter (25A) model, and the device fraud protection in the case of qualified deviations done with the possibility of delivery of information about the status or error parent controls devices.

24. The device is protected from fraud by item 16, wherein installed on at least one additional coil (22) of interfering field, and coil (17, 22) interfering field are executed with the possibility of various spatial distribution, or of a different orientation, or variable geometry of the magnetic field and especially located near holes (6) entry for the media (2) data in the form of card and supplied uncorrelated between the stochastic signals.

25. The device is protected from fraud by item 16, wherein the coil (17) of interfering fields and magnetic coil (10) read unified in a common building block.

26. Reader for authorized registration information stored magnetically on the media (2) the data in chart form, wherein the reader (1) contains the device of protection against fraud by item 16.

27. Reader on .26, wherein the device of protection against fraud configured to automatically lock holes (6) entry for the media (2) data in the form of a card, if by means of a generator (16) of interfering field reader (1) set to an invalid operation or manipulation.

28. Machine for the provision of banking services, wherein the machine for the provision of banking services contains the reader on .26.

29. Access control system, wherein the access control system contains the reader on .26.