KR20160033506A - Device for collecting the side channel and method of side channel analysis system having the device - Google Patents

Abstract

Disclosed is a technology for collecting side channel signals of a contactless device. According to an aspect of the present invention, an apparatus for collecting side channel signals includes: a reader which supplies power to the contactless device placed apart from the reader at a certain distance and transmits a carrier signal; a signal extraction unit which extracts a side channel signal from a signal generated to correspond to the carrier signal in the contactless device which operates by receiving the power; and a signal collection unit which synchronizes the extracted side channel signal with a trigger signal generated by the reader and performs sampling of the side channel signal. The signal extraction unit receives the signal, generated in the contactless device, in a predetermined location according to intensity of the carrier signal received from the reader. The purpose of the present invention is to provide a technology which can minimize the carrier signal and efficiently collect the side channel signal of the contactless device.

Description

[0001] The present invention relates to a subchannel signal collecting apparatus and a subchannel analyzing system including the same,

[0001] The present invention relates to a key leakage security verification technique of a non-contact type device, and more particularly to a technique for collecting a sub-channel signal of a non-contact type device.

Even a mathematically secure cryptographic algorithm, the side channel analysis technique that finds important data such as cryptographic keys using timing information, power consumption, electromagnetic wave, etc. leaked in the calculation process is the most powerful analysis technique of cryptographic algorithm safety analysis It is acknowledged. Among them, the subchannel analysis technique using a power signal or an electromagnetic wave signal uses a characteristic that the static / dynamic power consumption of a general-purpose processor or a hardware processor in which a cryptographic algorithm is performed varies depending on input data.

In particular, security devices such as smart cards have become a necessity for subchannel analysis to verify key leak safety. In this case, in order to apply the subchannel analysis technique to a real secure device rather than a simulation, a subchannel signal such as a power signal or an electromagnetic wave signal generated during the execution of the encryption algorithm must be collected.

Here, the smart card, which is a noncontact type device, is a card that operates by receiving power from the card reader for RF operation of the card. For this purpose, the card reader communicates with the smart card using a carrier signal having relatively higher signal strength than the signal generated from the smart card. In this case, in order to improve the accuracy of the key leakage security verification for the smart card, statistical processing should be performed using the sub-channel signal generated from the smart card, except for the carrier signal. However, the carrier signal generated in the card reader makes it difficult to extract the sub-channel signal generated in the smart card.

In addition, Near Field Communication (NFC) devices use the same interface as a smart card. Depending on the operating environment, the NFC device operates by receiving power from an NFC reader, such as a smart card, or by using an internal power supply. As described above, even in the case of the NFC device, the signal transmitted from the NFC reader makes it difficult to analyze the key leak of the NFC device even though the operating environment is different from that of the smart card.

An object of the present invention is to provide a technical solution for efficiently collecting subchannel signals of a noncontact device while minimizing a carrier signal generated from a reader.

According to an aspect of the present invention, there is provided a subchannel signal collecting apparatus including a reader for supplying power to a contactless device separated by a predetermined distance, a reader for transmitting a carrier signal, A signal extracting unit for extracting a subchannel signal from a signal generated corresponding to the carrier signal and a signal collecting unit for sampling the extracted subchannel signal in synchronization with a trigger signal generated by the reader, And receives a signal generated at the contactless device at a predetermined position according to the intensity of the carrier signal received from the reader.

According to another aspect of the present invention, there is provided a subchannel signal collecting method using a subchannel analyzing system including a subchannel signal collecting apparatus, the method comprising the steps of: receiving from a reader transmitting a carrier signal to a non- Searching for a position of the signal extracting unit in accordance with the intensity of the carrier signal to be received, and collecting the subchannel signal received from the contactless device at the signal extracting unit of the searched position.

According to an embodiment of the present invention, a subchannel signal can be efficiently collected at a position where a carrier signal generated in a reader communicating with a noncontact device is minimized and a subchannel signal generated in a contactless device is maximized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall configuration diagram of a subchannel analysis system including a subchannel signal collecting apparatus according to an embodiment of the present invention; FIG.
2 is a diagram illustrating a configuration of a reader of a subchannel signal collecting apparatus according to an embodiment of the present invention.
3 is a diagram illustrating a configuration of a signal extracting unit and a signal collecting unit of a subchannel signal collecting apparatus according to an embodiment of the present invention.
4 is a view illustrating a measurement coil of a signal extracting unit of a subchannel signal collecting apparatus according to an embodiment of the present invention;
5 is a diagram illustrating a configuration of a filter circuit of a signal extracting unit of a subchannel signal collecting apparatus according to an embodiment of the present invention.
FIG. 6 is a first diagram illustrating a jig for fixing a position of a signal extracting unit of a subchannel signal collecting apparatus according to an embodiment of the present invention; FIG.
7 is a second diagram illustrating a jig for fixing a position of a signal extracting unit of a subchannel signal collecting apparatus according to an embodiment of the present invention;
FIG. 8 is a flowchart illustrating a method of searching for a position of a subchannel signal collecting device in a subchannel analysis system according to an embodiment of the present invention. FIG.
9 is a flow chart of a method for collecting subchannel signals in a subchannel analysis system according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. And is provided to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the claims. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In the present specification, the singular form includes plural forms unless otherwise specified in the specification. It is noted that " comprises, " or "comprising," as used herein, means the presence or absence of one or more other components, steps, operations, and / Do not exclude the addition.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, like reference numerals refer to like elements throughout. In the drawings, like reference numerals are used to denote like elements, and in the description of the present invention, In the following description, a detailed description of the present invention will be omitted.

The subchannel analysis system of the noncontact type device according to the embodiment of the present invention collects the subchannel signals of the noncontact type device for the key leakage safety analysis using the subchannel signal collecting device. To this end, the subchannel analysis system first searches for the location of the subchannel signal acquisition device from which subchannel signals are well collected from the contactless device. At this time, the position of the subchannel signal collecting device in which the waveform of the subchannel signal is well collected can be searched according to the strength of the carrier signal received from the reader communicating with the contactless device. For example, the subchannel signal collecting apparatus is a position at which the intensity of the carrier signal received from the reader is minimized.

The subchannel analysis system then receives the subchannel signal of the contactless device, which is collected by the subchannel signal acquisition device at the searched location. The received subchannel signal is used for key leak safety analysis of the contactless device.

1 is an overall configuration diagram of a subchannel analysis system including a subchannel signal collecting apparatus according to an embodiment of the present invention. 1, the subchannel analysis system 10 includes a subchannel signal acquisition device 100, a noncontact device 200, and a subchannel signal analysis device 300. [

The contactless device 200 is a device that converts plain text data input from an external device (e.g., the reader 110 or the like into ciphertext data and stores the ciphertext data or decrypts the stored ciphertext data into plain text data and outputs the decrypted data.) Although not shown, The memory 200 may include a nonvolatile memory device for storing data, a block encryption chip for decrypting the encrypted data using the master key, a volatile memory for storing the master key or for storing the encrypted data, and the like. For example, the contactless device 200 may be a smart card such as a Java card, an NFC tag, or the like.

The sub-channel signal analysis apparatus 300 controls the overall operation of the sub-channel analysis system 10, and may be a computer (PC). For example, the subchannel signal analyzer 300 may transmit a control signal to the subchannel signal collecting apparatus 100 for key leakage safety analysis. Here, the transmitted control signal may include a signal (command) for operation of the subchannel signal collecting apparatus 100 and the contactless device 200.

Also, the sub-channel signal analyzer 300 can receive the response data and the sub-channel signal according to the cryptographic operation of the contactless device 200 through the sub-channel signal collector 100. The received data and subchannel signals are used for key leak stability analysis. For example, the subchannel signal analyzer 300 may obtain the signal generated by repeatedly performing the same cryptographic operation on the noncontact device 200, and detect the fine change of the obtained signals to find the cryptographic key.

The subchannel signal collecting apparatus 100 supplies power to the noncontact type device 200 according to a control signal of the subchannel signal analyzing apparatus 300 and transmits data and subchannel signals And transmits it to the subchannel signal analyzing apparatus 300.

A subchannel signal collecting apparatus 100 according to an embodiment of the present invention includes a reader 110, a signal extracting unit 120, and a signal collecting unit 130.

The reader 110 supplies power to the noncontact type device 200 spaced apart by a predetermined distance to transmit and receive data. For example, when the reader 110 receives a control signal (command) from the sub-channel signal analysis apparatus 300, it transmits a command (for example, APDU (Application Protocol Data Unit) command) And transmits the carrier signal (RF signal) including the signal to the noncontact type device 200. Here, the APDU command is a unit of data exchanged between application entities in the application layer, and may include application protocol (application) control information and application layer user data.

The reader 110 processes the response data transmitted from the non-contact type device 200 in response to a command included in the carrier signal, and transmits the response data to the sub-channel signal analysis apparatus 300. 2, the reader 110 includes a PC communication module 111, a board control CPU 112, an RF processing processor 113, a power module 114, an RF antenna 115, an RF matching Circuitry 116 and a trigger signal measurement module 117. FIG.

The power module 114 supplies power necessary for driving the reader 110.

The PC communication module 111 is for data transmission / reception with the sub-channel signal analysis device 300 and provides wired communication or wireless communication. The reader 110 may receive a control signal (command) from the sub-channel signal analysis apparatus 300 through the PC communication module 111. [ In addition, the reader 110 can transmit data received from the non-contact type device 200 to the sub-channel signal analysis device 300 through the PC communication module 111.

The reader 110 can transmit and receive data to and from the contactless device 200 through the RF antenna 115 and the RF matching circuit 116.

The RF processor 113 is for processing data for communication with the contactless device 200 and can process data using the protocol according to the type of the contactless device 200. As an example, when the contactless device 200 is a smart card such as a Java card, the RF processing processor 113 may support the ISO 7816 protocol. As another example, if the non-contact device 200 is an NFC tag, the RF processor 113 may support the ISO 18092 protocol.

The board control CPU 112 controls the overall operation of the reader 110. For example, the board control CPU 112 may transmit control signals received from the subchannel signal analysis apparatus 300 to the contactless device 200 by processing (modulating or demodulating) the signals and data, And transmits the received response to the sub-channel signal analysis apparatus 300. In addition, the board control CPU 112 generates a trigger signal for the signal measurement reference signal of the subchannel signal collecting apparatus 100.

The trigger signal measurement module 117 outputs the trigger signal generated by the board control CPU 112 to the signal collector 130. The trigger signal thus outputted becomes a synchronization reference of the subchannel signal in the signal collecting unit 130. [

The signal extracting unit 120 extracts a sub-channel signal from a signal generated in the non-contact type device 200. To this end, the signal extracting unit 120 includes a measuring coil 121 and a filter circuit 122, as shown in FIG.

The measurement coil 121 has a shape corresponding to the antenna pattern of the noncontact type device 200. At this time, the measurement coil 121 is formed as close as possible to the noncontact type device 200.

For example, when the noncontact type device 200 is a smart card, the appearance or pattern of most of the smart cards is a shape of a small square surrounded by the shape of the smart card as shown in FIG. 4 (a). In this case, the measurement coil 121_1 may be implemented as a square similar to the antenna pattern of the smart card as shown in FIG. 4B.

As another example, when the noncontact type device 200 is an NFC card, the antenna pattern of the NFC card varies, and the antenna of most NFC cards is composed of an antenna coil smaller than the antenna of the smart card. Accordingly, when the noncontact type device 200 is an NFC card, the measurement coil 121_2 may have a circular (or square) shape as shown in FIG. 4C so as to measure the signal of the NFC card as much as possible.

The filter circuit 122 extracts a signal having a predetermined frequency or less from the signal measured by the measuring coil 121 as a sub-channel signal. For example, the filter circuit 122 removes a carrier signal generated by the reader 110 and extracts a sub-channel signal generated in the non-contact type device 200. To this end, the filter circuit 122 includes a matching circuit 122_1, a rectifying circuit 122_2, and a low pass filter (LPF) circuit 122_3 as shown in FIG. 5A.

The matching circuit 122_1 is a circuit for impedance matching signals received from the non-contact type device 200 and the reader 110. [ The matching circuit 122_1 selects an appropriate capacitor value so that the signal of the noncontact type device 200 can be measured as much as possible without interfering with the communication between the reader 110 and the noncontact type device 200. [

The rectifying circuit 122_2 is a circuit for full-wave rectifying a signal of a sinusoidal waveform transmitted from the matching circuit 122_1. At this time, the rectifying circuit 122_2 may be a bridge rectifying circuit. This is because the sub-channel signal generated from the noncontact type device 200 is transmitted from the reader 110 even when the measurement coil 121 is configured to collect the signal generated from the noncontact type device 200 as much as possible, It is buried in (mixed) with the measurement.

If the signal measured by the measuring coil 121 is weak, an amplifying circuit 122_4 is provided between the matching circuit 122_1 and the rectifying circuit 122_2 of the filter circuit 122, as shown in Fig. 5 (b) Can be added and configured.

The low-pass filter circuit 122_3 is for passing only the frequency signal of the carrier frequency of the reader 110 (for example, 13.56 MHz) or less, to the signal rectified by the rectifying circuit 122_2. At this time, the signal having passed through the low-pass filter circuit 122_3 can be extracted as a sub-channel signal.

Here, the signal rectified by the rectifying circuit 122_2 may be filtered to several tens of KHz to several KHz or less depending on the value of each element included in the low-pass filter circuit 122_3. At this time, each device value may be configured differently according to RF characteristics of the noncontact type device 200. Through this process, the signal extracting unit 120 can extract a sub-channel signal from a signal generated in the non-contact type device 200.

The signal extracting unit 120 receives a signal from the contactless device 200 at a predetermined position according to the intensity of a signal (carrier signal) received from the reader 110. [ At this time, the signal extracting unit 120 can receive a signal from the contactless device 200 at a position where the strength of the carrier signal received from the reader 110 is minimized.

For example, the signal extracting unit 120 receives a signal around the interface between the reader 110 and the non-contact type device 200. At this time, the communicable area varies depending on the characteristics of the non-contact type device 200, and the position of the signal extraction part 120 and the non-contact type device 200 closely attached thereto can be varied to find a point where the signal is good .

The relative positions of the signal extracting unit 120 and the reader 110 may be changed by the separate jigs 140 and 140 '. The signal extracting unit 120 and the reader 110 can be fixed at positions where the carrier signals received by the signal extracting unit 120 are minimized by the jigs 140 and 140 '. At this time, the jigs 140 and 140 'are realized by a material such as acrylic which does not affect RF communication.

The jig 140 includes a signal extraction unit 120 and a contactless device 200 and a reader 110 on both sides of a body 140_1 having a hexahedron shape or a rectangular parallelepiped shape as shown in FIG. A plurality of slots 140_2 may be stacked. As shown in FIG. 6 (b), the side surface of the jig 140 may have a plurality of slots 140_2 stacked.

The reader 110, the signal extracting unit 120 and the contactless device 200 may be located in any one of a plurality of slots 140_2 of the jig 140, as shown in FIG. 6 (c) . For example, the reader 110 is fixed to the first slot 140_3 of the jig 140, and the signal extracting unit 120 extracts a signal having a minimum strength of a carrier signal received from the reader 110 of the jig 140 And is fixed to the second slot 140_4. At this time, since the noncontact type device 200 is in close contact with the signal extraction unit 120, it is fixed to the same slot (second slot 140_4).

The signal extracting unit 120 and the contactless device 200 are connected to the reader 110 and the vertical (z) direction according to the slot by the jig 140 as shown in FIGS. 6 (a) and 6 (b) The relative distance of the axes may become farther or closer. Also, the relative distance between the signal extracting unit 120 and the reader 110 may be increased or decreased along the horizontal (x) axis depending on the degree of insertion into the slot.

If the reader 110 does not fit in the slot (not mounted), the jig 140 may be placed (raised) on the reader 110.

As another example, the jig 140 'may include a leader jig 140'_2 that fixes the leader 110 on the body 140'_1, a leader jig 140'_2 that fixes the leader jig 140'_2, And a signal extracting unit jig 140'_3 that moves in three axial directions with reference to the signal extracting unit 120 and fixes the signal extracting unit 120. [ The signal extracting unit jig 140'_3 includes a fixing plate for mounting the signal extracting unit 120 and the noncontact type device 200, a horizontal arm for moving the fixing plate up and down along the column, A moving plate. The signal extracting unit 120 can be moved in the y axis direction according to the position on the fixing plate with respect to the reader 110 and can be moved in the z axis direction according to the vertical movement of the horizontal arm, Axis direction, as shown in FIG. Accordingly, the signal extracting unit 120 can change its position relative to the reader 1110 in three axial directions.

The signal collecting unit 130 samples the subchannel signal extracted by the signal extracting unit 120 in synchronization with a trigger signal generated by the reader 110. At this time, the signal collecting unit 130 may be an oscilloscope physically separated from the signal extracting unit 120. For example, the signal collecting unit 130 may be an oscilloscope having a sampling rate and a bandwidth of several hundreds of megahertz.

The sampled signal is transmitted to the subchannel signal analyzer 300 and can be used for key leak safety analysis of the noncontact device 200.

Meanwhile, the subchannel analysis system 10 collects waveforms of subchannel signals for key leakage safety analysis of the noncontact device 200 through a position search process of the subchannel signal collecting device 100 and a subchannel signal collecting process . First, the subchannel analysis system 10 calculates a position at which the strength of a carrier signal received from the reader 110 by the subchannel signal collecting apparatus 100 is minimized while the cryptographic operation is being performed in the contactless device 200 Search. The subchannel analysis system 10 then analyzes the key leakage security of the contactless device 200 using the subchannel signals collected by the subchannel signal acquisition device 100 at the searched location.

Hereinafter, the position search process of the sub-channel signal analysis apparatus 300 will be described in detail with reference to the operation flow chart of FIG.

In step S810, the subchannel analysis system 10 powers on the carrier signal of the reader 110. Accordingly, the reader 110 is activated by the control signal output from the sub-channel signal analysis apparatus 300, and turns on the power of the carrier signal. At this time, the carrier signal can be transmitted from the reader 110 to the contactless device 200.

In step S820, the subchannel analysis system 10 selects an application to operate in the contactless device 200. [ For example, the subchannel signal analyzer 300 may transmit an identifier (Application Identifier) of an application to be operated in the contactless device 200 to the reader 110 along with a control signal to select an application. Here, AID is a data element that identifies an application in the contactless device 200. At this time, depending on the type of the noncontact type device 200 (e.g., when the noncontact type device 200 performs only one application), step S820 may be omitted.

In step S830, the contactless device 200 of the subchannel analysis system 10 performs a cryptographic operation operation for an application corresponding to the AID information received from the reader 110 together with the carrier signal. The contactless device 200 can perform a cryptographic operation in accordance with a command word (APDU command) included in the carrier signal received from the reader 110, and transmit the resultant value to the reader 110. At this time, in the non-contact type device 200, a sub-channel signal may be generated due to the cryptographic operation being performed.

On the other hand, there is a case where a power source required for performing the process of performing an application selection process in step S820 and a cryptographic operation process in step S830 is different. If the supplied power is too low or too high, the application selection process and the cryptographic operation may not operate normally. At this time, the subchannel analysis system 10 can adjust the antenna power of the reader 110 by changing the RF processor set value of the reader 110.

Generally, the process of selecting an application requires a relatively higher power than the process of performing a cryptographic operation. In this case, the subchannel analysis system 10 increases the antenna power of the reader 110 before performing step S820, and then performs an application selection process. Before performing step S830, The cryptographic computation operation can be performed.

In step S840, the subchannel analysis system 10 adjusts the positions of the noncontact device 200 and the signal extraction unit 120. [ At this time, the noncontact type device 200 and the signal extraction unit 120 can be adjusted in position around the interface between the reader 110 and the noncontact device 200 by the jig 140 or 140 '.

In step S850, the subchannel analysis system 10 observes the waveform of the signal generated in the noncontact device 200 to confirm that the signal is good. At this time, the signal is a sub-channel signal and is collected by the sub-channel signal collecting apparatus 100. The subchannel signal analyzer 300 determines whether the intensity of the carrier signal received from the reader 110 is minimized while the predetermined waveform pattern predetermined according to the application is collected by the subchannel signal collecting apparatus 100, Is good. At this time, the subchannel analysis system 10 can search for a position where a good signal is collected while changing the position of the subchannel signal collecting apparatus 100. At this time, the subchannel analysis system 10 may change the relative positions of the signal extracting unit 120 and the reader 110 of the subchannel signal collecting apparatus 100.

As a result of checking in step S850, if the signal is good, the subchannel analysis system 10 stores the setting information of the noncontact device 200 and the subchannel signal collecting apparatus 100. [ For example, the setting information includes position information of the noncontact device 200, position information of the signal extractor 120, environment of the signal collecting unit 130 (e.g., oscilloscope setting value), and the like based on the reader 110 .

Through this process, the subchannel analysis system 10 can search for the position of the subchannel signal collecting apparatus 100.

When the position searching process of the subchannel signal collecting apparatus 100 is completed, the subchannel analyzing system 10 may perform a process of collecting subchannel signals for key leakage safety analysis.

Hereinafter, the subchannel signal collecting process will be described in detail using the operation flowchart of FIG.

In step S910, the subchannel analysis system 10 sets the number (N) of waveforms to be collected. Here, the number of waveforms to be collected may be set differently according to the application, and may be set to be equal to or greater than the minimum number of waveforms required for key leak safety analysis.

In step S920, the subchannel analysis system 10 turns on the power of the carrier signal of the reader 110. [ For example, the sub-channel signal analyzer 300 transmits a control signal to the reader 110, and the reader 11 receiving the control signal is activated to turn on the power of the carrier signal. Accordingly, the carrier signal can be transmitted from the reader 110 to the contactless device 200. [ At this time, the subchannel signal collecting apparatus 100 communicates with the contactless device 200 at the position searched in the previous position search process.

In step S930, the subchannel analysis system 10 selects an application to be operated in the contactless device 200, and in step S940, the contactless device 200 performs a cryptographic operation process corresponding to the operation application.

At this time, there is a case where the power source required for performing the process of performing the cryptographic operation in step S940 and the application selection process in step S930 are different. . In this case, the subchannel analysis system 10 increases the antenna power of the reader 110 before performing step S930, and then performs an application selection process. Before performing step S940, The cryptographic computation operation can be performed.

In step S950, the subchannel analysis system 10 stores the plaintext and the ciphertext used for the waveform and cryptographic operation of the subchannel signal. This is because a sub-channel signal generated from the non-contact type device 200 for analyzing the key leakage security as well as a plain text and a cipher text used for the cryptographic operation of the contactless type device 200 are required. At this time, the sub-channel signal analyzing apparatus 300 can receive the plaintext and the ciphertext from the reader 110 of the subchannel signal collecting apparatus 100. In addition, the sub-channel signal analyzing apparatus 300 receives the sub-channel signal extracted by the signal extracting unit 120 in synchronization with the trigger signal output from the reader 110, and samples the sampled signal through the signal collecting unit 130 can do.

If an error occurs in receiving and storing the waveform of the subchannel signal and the plaintext and the cipher text in step S950, the subchannel analysis system 10 turns off the power of the carrier signal of the reader 110, The process moves to step S920 to perform again the operation of turning on the power of the carrier signal.

In step S960, the subchannel analysis system 10 confirms the number of traces (waveforms, plain text, and ciphertexts) stored through the iterative execution of steps S940 and S950.

If it is determined in step S960 that the number of stored traces is a predetermined number (N), the subchannel analysis system 10 ends the subchannel signal collecting operation.

Through this process, the subchannel analysis system 10 can collect subchannel signals for key leakage safety analysis.

As described above, according to the embodiment of the present invention, the subchannel signal generated by the reader communicating with the noncontact device can be efficiently collected at the position where the carrier signal is minimum and the subchannel signal generated in the contactless device is the maximum.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is to be understood that the invention may be embodied in other specific forms. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the scope of the claims and their equivalents shall be construed as being included within the scope of the present invention.

110: reader 120: signal extracting unit
130: signal collecting unit 140, 140 ': jig
200: contactless device 300: subchannel signal analyzer

Claims (13)

A reader for supplying power to the noncontact type device spaced apart by a predetermined distance and transmitting a carrier signal;
A signal extracting unit for extracting a subchannel signal from a signal generated corresponding to the carrier signal in the noncontact type device operating with the power supply; And
And a signal collecting unit for sampling the extracted sub-channel signal in synchronization with a trigger signal generated by the reader,
The signal extracting unit may receive a signal generated at the contactless device at a predetermined position according to the intensity of the carrier signal received from the reader
Channel signal acquisition device of a non-contact device.
The signal extracting apparatus according to claim 1,
Receiving a signal generated at the non-contact type device at a position where the intensity of the carrier signal received from the reader is minimized
Channel signal acquisition device of a non-contact device.
The signal extracting apparatus according to claim 1,
A measuring coil having a shape corresponding to the antenna pattern of the noncontact type device; And
And a filter circuit for extracting, from the signal received through the measurement coil, a signal having a predetermined frequency or less as a subchannel signal
Channel signal acquisition device of a non-contact device.
The filter circuit according to claim 3,
A matching circuit for impedance matching signals received from the contactless device and the reader;
A rectifying circuit for full-wave rectifying a sine wave signal transmitted from the matching circuit; And
And a low pass filter (LPF) circuit for filtering the frequency of the carrier signal or less to extract a sub-channel signal
Channel signal acquisition device of a non-contact device.
The method according to claim 1,
A signal extracting unit for extracting a signal from the signal extracted by the signal extracting unit,
Further comprising: means for generating a signal from the sub-channel signal.
6. The apparatus according to claim 5,
Body; And
And a plurality of slots formed on both sides of the body for fixing the signal extractor and the reader,
The reader is fixed to a first slot of the jig,
Wherein the signal extracting unit is fixed in a second slot in which the strength of a carrier signal received from the reader is minimized
Channel signal acquisition device of a non-contact device.
6. The apparatus according to claim 5,
Body;
A reader jig for fixing the reader on the body; And
And a signal extraction unit jig that moves in three axial directions with respect to the reader jig and fixes the signal extraction unit
Channel signal acquisition device of a non-contact device.
A subchannel signal acquisition method by a subchannel analysis system including a subchannel signal acquisition device,
Searching for a position of the signal extracting unit in accordance with the strength of a carrier signal received from a reader that transmits a carrier signal to a contactless device that is separated by a predetermined distance; And
Collecting subchannel signals received from the contactless device at the signal extractor of the searched location;
/ RTI >
9. The method of claim 8, wherein the searching comprises:
Selecting an application to be performed in the contactless device;
Observing a waveform of a subchannel signal received from the noncontact type device during a cryptographic computation operation in the noncontact type device according to execution of the application; And
Storing the setting information of the position of the signal extracting unit when the waveform pattern of the sub-channel signal is received in response to the application;
Channel signal.
10. The method of claim 9,
Transmitting an application identifier (AID) information to the subchannel signal collecting device together with a control signal to select the application to be performed in the contactless device
In subchannel signal acquisition method.
10. The method of claim 9,
Storing the setting information of the position of the signal extracting unit in which the intensity of the carrier signal received from the reader is minimized
In subchannel signal acquisition method.
9. The method of claim 8,
Turning on a power of a carrier signal transmitted to the noncontact type device;
Selecting an application to be performed in the contactless device;
Storing a waveform of a subchannel signal generated during a cryptographic computation operation in the contactless device and plain text data and ciphertext data used in the cryptographic computation according to execution of the application; And
Terminating the operation of collecting the subchannel signal when the waveform of the stored subchannel signal, the plaintext data, and the ciphertext data are stored by a predetermined number;
Channel signal.
13. The method of claim 12,
When a failure occurs in storing the waveform of the sub-channel signal, the plaintext data and the ciphertext data, the power of the carrier signal transmitted to the non-contact type device is turned off, ;
Wherein the subchannel signal further includes a subchannel signal.

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