JPH10303886A - Device and method for collating identification signal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve security by preventing random numbers from being continuously overlapped. SOLUTION: This device is composed of a device 1, which enciphers an identification signal, to be detected and a detection device 3 for collating the identification signal through deciphering. The detection device 3 has a random number generation part 13 for generating the random number to be used for enciphering and outputting it to the device 1 to be detected, a storage part 14 for storing the prescribed number of random numbers counted from the latest output among the generated random numbers, and a random number change part 20 for monitoring the generated random number and the random numbers in the storage part 14 and reloading the overlapped random number into different random number. The random number change part 20 has a compare means 21 for successively comparing the generated random number with the random numbers in the storage part 14 and an output control means 22 for repeatedly controlling the generation and output of random number while inhibiting the transmission to the device 1 to be detected to the random number generation part 13 until no coincident random number exists when the relevant means 21 detects the coincidence of random numbers. The random number change part 20 can be constituted so as to change such a random number into different random number through arithmetic processing as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an identification signal matching device and an identification signal matching method suitable for, for example, a keyless entry system.

[0002]

2. Description of the Related Art Conventionally, a key device as a portable terminal and a lock device as a main device installed on a control target side such as a door are constituted by a key device in which the operation of the key device by radio is registered in advance. There has been proposed a keyless entry system in which a locking device identifies whether or not the key is unlocked / unlocked.
In this conventional keyless entry system, an identification signal is transmitted from a key device to a lock device using infrared rays or radio waves to lock or unlock.

In such a conventional keyless entry system, since one-way communication in which the same identification signal is always transmitted from the key device side, when this communication is intercepted, the identification signal is easily stolen. There is. In particular, when the identification signal is transmitted using infrared rays, the identification signal can be easily copied according to the same principle as a so-called learning remote controller, which may be a social problem. Furthermore, the above-mentioned keyless entry system has a serious problem in terms of security such that a specific identification signal can be searched by trying various identification signals many times.

Therefore, a password signal indicating a password is transmitted from the portable device (key device) to the main device (lock device), and the main device receives its own password calculated in the operation processing of the password signal and the received password. A keyless entry system that determines a match with a numerical value has been previously proposed. In such a previously proposed keyless entry system, the main unit determines whether or not its own secret value calculated and registered in the arithmetic processing of the numerical signal and the received secret value match with each other. There is a high advantage.

[0005]

In such a keyless entry system, when generating an encrypted password in the arithmetic processing of a numeric signal, the numeric signal used in the arithmetic processing generally has randomness in the generated numeric value. In many cases, random numbers are used with emphasis on.

However, if this random number is generated completely at random, the same numerical value may appear twice or three times in succession with a certain probability. This is a factor that lowers the security of the keyless entry system. May get. For example, when an outsider who obtains identification code information used continuously intercepts a signal corresponding to the known identification code while the identification code is being transmitted while being encrypted. If the same random number is continuously used for encryption, this interception may be repeated several times, which may make it easier to analyze the arithmetic processing of encryption.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an identification signal collating apparatus and an identification signal having improved security by effectively preventing random numbers used for encrypting an identification code from being generated as continuous values. It is intended to provide a matching method.

[0008]

According to the present invention, there is provided an identification / verification apparatus for encrypting a first identification signal and transmitting the encrypted identification signal;
It is composed of two types of devices capable of mutually transmitting and receiving signals wirelessly, such as a detection device for determining whether the detected device is a registered device or not. The detection device,
A random number generator that generates a random number used for the encryption and outputs the random number signal to the device to be detected as a random number signal, decrypts the received first identification signal after the encryption, and obtains a code obtained by the decryption. The first identification signal before conversion is compared with a second identification signal stored in advance. The detection device includes a storage unit that stores a predetermined number of random numbers in a random number output from the random number generation unit and outputs a random number output from the random number generation unit and a random number output from the storage unit. And a random number changing unit that monitors the random numbers and, when a matching random number exists, replaces the matching random number with a different random number and transmits the replaced random number to the detected device.

Preferably, the random number changing unit in the present invention is a comparing unit that sequentially compares the random number output from the random number generating unit and the random number in the storage unit, and when the comparing unit determines that the random numbers match. And output control means for repeatedly controlling the generation and output of the random number while prohibiting the random number generation unit from transmitting to the detected device until the comparison means determines that there is no matched random number.

In another preferred configuration of the random number changing unit, a comparison unit for comparing the random number output from the random number generation unit with the latest random number in the storage unit, and the comparison unit determines whether the random numbers match. In such a case, there is provided an arithmetic processing means for performing predetermined arithmetic processing on the coincident random numbers and generating the different random numbers.

In the identification signal collating device having such a configuration,
For example, the random number generator generates a random number in response to a response request from the detected device. The generated random number is compared with a random number in a storage unit that stores a random number previously generated and used for encryption, and it is confirmed that the random number does not overlap with a predetermined number of random numbers output in the past. The signal is output to the detection device and is used for encrypting the first identification signal. At this time, if it is determined that the random numbers are duplicated, the generation of the random numbers is repeated until no more random numbers match, or a change is made so that a different random number is always output.

For this reason, the random numbers generated in the identification signal matching device are always different random numbers within a predetermined number of times used for the encryption, and the prevention of the duplication of the continuous random numbers is guaranteed.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of a keyless entry system for remotely controlling the opening and closing of a door according to the present invention. I do.

First Embodiment FIG. 1 is a block diagram showing a schematic configuration of an identification signal matching device (keyless entry system) according to this embodiment. The keyless entry system includes a portable key device 1 and a lock device 3 installed on the side of an object to be driven (for example, a door 2), which instructs opening and closing of the door 2 and performs locking / unlocking. . Usually, the key device 1 is assigned to each individual, and the lock device 3 is installed for each driven object. The key device 1 includes a switch unit 4 for instructing opening and closing of a door by a user operation, a signal processing unit 5 for performing various signal processing, a transmitting / receiving unit 6 for communicating with the lock device 3, and an owner of the key device 1. The key device 1 includes an ID memory 7 for storing an identification code unique to the key device 1 (hereinafter, a specific identification code IDS), and a battery 8 for supplying power to each of the units 5 to 7 of the key device 1.

The switch unit 4 is inserted in the middle of the power supply line of the battery 8 and includes an operation switch for instructing opening / closing of a door and locking / unlocking, a power switch of the key device 1, and the like.

The signal processing unit 5 generates a response request signal in response to the operation of the switch unit 4, and generates a specific identification code IDS
Is encrypted using a predetermined function and a random number, and is usually configured by, for example, a microcomputer.

The transmission / reception unit 6 transmits the response request signal and a signal indicating the encrypted specific identification code IDS (hereinafter, specific identification signal), and receives a random number signal used for encrypting the specific identification code IDS. And has the function of modulating these various signals into predetermined carrier waves and demodulating them.
There is no limitation to this modulation method, for example, a baseband method,
The ASK modulation method or the FSK modulation method is selected.
The baseband method has advantages that compared to modulation methods such as ASK and FSK, high-speed communication can be performed with low power consumption and the circuit configuration is simplified. Here, the predetermined carrier is
Any of infrared rays, light, radio waves, and ultrasonic waves may be used. Further, the transmission / reception unit 6 may be divided into a transmission unit and a reception unit.

When the signal processing section 5 is constituted by a microcomputer, the ID memory 7 may use its internal memory. In the case where the number of key devices 1 is small and the specific identification code IDS is simple, for example, the ID memory 7 may be omitted, and the specific identification code IDS such as a password may be received by key input in the switch unit 4. .

The locking device 3 includes a transmitting / receiving unit 9 for communicating with the key device 1, a driving device 10 for driving a door lock to perform locking / unlocking, a processing control unit 11, a registration ID memory 12,
A random number generation unit 13 that generates a random number and outputs it as a random number signal;
A random number memory 14; a battery 15 for supplying power to each of the components 9 to 14 of the lock device;
The power control unit 16 has a power supply control unit 16 for intermittently operating the power supply 15 and a timer 17 for giving a clock signal to the power supply control unit 16.

The transmission / reception unit 9 transmits a random number signal to the key device 1 and receives a specific identification signal. The transmission / reception unit 9 has the same function as the transmission / reception unit 6 on the key device side, and has a predetermined modulation method and carrier wave. (Infrared rays, light, radio waves or ultrasonic waves). The transmission / reception unit 9 may also be configured as a transmission unit and a reception unit.

The processing control unit 11 controls the output of the random number, the specific identification code IDS, and the identification code (hereinafter referred to as a registered identification code IDR) registered in advance to identify the specific person who is permitted to lock / unlock. It performs collation and various kinds of signal processing accompanying the collation, and controls the driving device 10 based on the collation result, and is usually composed of, for example, a microcomputer. The processing control unit 11
For example, as shown in FIG. 1, a decryption unit 18 that decrypts based on a received specific identification signal to obtain a specific identification code IDS before encryption, and registers a specific identification code IDS after decryption into a registration I
A collating unit 19 that collates with the registered identification code IDR from the D memory 12 and controls the driving device 10 according to the collation result;
And a random number changing unit 20 for controlling output of random numbers such as preventing overlapping with output random numbers in the past several times. Decryption unit 18
Is used to perform decryption using a decryption function and a random number used for encryption, and is connected so that a random number from the random number generation unit 13 can be input.

The registration ID memory 12 stores a number of registration identification codes IDR. As the memory 12, a built-in memory of a microcomputer can be used, and an external storage device or a portable recording medium can be used instead.

As the random number generator 13, for example, a binary counter having a predetermined number of bits can be used. in this case,
This is a pseudo random number in which the generation of the same random number is repeated periodically. As a random number generator that generates random numbers without periodicity,
Although not particularly shown, for example, a shift register and an adder (exc
There is a circuit for generating an M-sequence (Maximum Length Code) composed of a "lusive OR". In this circuit, a tap is appropriately provided in the middle of a shift register having a predetermined number of bits, and an empty input of an adder inserted in a feedback loop of the shift register is connected to the tap.

The random number memory 14 outputs a predetermined number of random numbers X used in the past to encrypt the specific identification code IDS by being output from the processing control unit 11 to the transmission / reception unit 9 from the latest one. Only memorized. The random number memory 14 is composed of, for example, a FIFO (First-In First-Out) memory, and the stored content is controlled and rewritten by the processing control unit 11 every time a random number is output from the processing control unit 11.

The power control unit 16 is usually provided inside a microcomputer constituting the processing control unit 11. In general, a microcomputer has a normal operation mode and a low power consumption mode in a standby state in which only a part of the microcomputer operates. However, the power supply control unit 16 can be a microcomputer part that operates even in the low power consumption mode. . On the other hand, the processing control unit 11 can be a microcomputer part which stops power supply in the low power consumption mode and operates only in the normal operation mode.

In the identification signal collating device, the lock device 3 is controlled by the power control unit 16 and operates intermittently. In the intermittent operation, if the operation of the key device 1 is optional and it is not known how long the response request will take, and if power is constantly supplied to each unit in the lock device 3, the power consumption is large and the battery 15 is greatly consumed. The operation (power supply) of the lock device 3 is performed intermittently at a predetermined cycle to reduce power consumption.
The power control unit 16 controls the lock device 3 as in the normal intermittent operation.
The power supply may be controlled so as to start or stop all the units 9 to 14 at the same time, but here, the start timing is changed. That is, when the power supply control unit 16 starts the power supply from the stop state in the intermittent operation,
Processing control unit 11, registration ID memory 12, random number generation unit 13
In addition, control is performed to start the power supply to the transmitting / receiving unit 9 (strictly, only the receiving unit) ahead of the start timing of the power supply to the random number memory 14 by a predetermined time. Details of the timing control of the intermittent operation will be described later.

The random number changing unit 20 in the present embodiment has a comparing unit 21 and an output control unit 22. Comparison means 2
1 compares the latest random number Xk from the random number generation unit 13 with the random numbers Xk-1, Xk-2,... The random number generator 13 and the random number memory 14
Is connected. The output control means 22 includes the random number generation unit 1
3 is provided in the middle of the output path of the transmission / reception unit 9 to prohibit the output of the random number Xk based on the comparison result of the comparison unit 21 or instruct the random number generation unit 13 to generate the random number again.
This is a means for controlling the output of k.

Next, referring to the timing chart of FIG. 3, an example in which the identification signal matching method of the present embodiment is applied to the above-described identification signal matching device will be described with reference to FIG.
Will be described along the flowchart of FIG. Now, the specific identification code IDS is stored in the ID memory 7 in the key device 1, and the registered identification code IDR is stored in the registered ID memory 12 in the lock device 3.
Is registered in advance. Although the number of bits of these identification codes IDS and IDR and the number of bits of the random number generated by the random number generation unit 13 are not limited, here, for convenience of explanation, it is assumed that each of them is a 24-bit code.

As described above, the lock device 3 performs the intermittent operation, and the start timing of the transition from the stop state to the operation state is set earlier by ΔT in the transmission / reception unit 9 than other parts. That is, the power control unit 16 controls the parts other than the transmission / reception unit 9 based on the time signal from the timer 17 with the operation time T1 and the stop time T2 as shown in FIG. As shown in the figure, the operation time (T1 + ΔT) and the stop time (T2−Δ
The intermittent operation is performed under the control of T).

During the intermittent operation, the user operates the key device 1
When the user operates the switch unit 4 and presses the switch, the electric power from the battery 8 is supplied to the respective units 5 to 6, and the user operates the switch unit 4 to open or close the door 2. Is issued, the operation signal is output to the signal processing unit 5 (step S1). Accordingly, the signal processing unit 5 generates a response request signal including a command to open or close the door, and for example, as shown in FIG.
The response request signal is continuously transmitted to the lock device 3 for 0 msec (step S2). The transmission period of the response request signal is set to be equal to or longer than the period of the intermittent operation (T1 + T2), so that the lock device 3 can receive the response request signal even when the switch of the key device 1 is turned on at any timing. ing.

When this response request signal is received by the lock device 3 (step S3, see FIG. 3D), the power supply control unit 16 determines that the response request signal is being transmitted. Supply power. When the transmission and reception unit 9 enters a state in which the transmission and reception unit 9 can stably receive after the elapse of the time ΔT, the power supply control unit 16
Starts power supply to the processing control unit 11. The power supply to the other parts 10 to 14 is started at the same time as the power supply to the processing control unit 11 or at an appropriate timing thereafter. This timing is arbitrary as long as the subsequent processing is not hindered, but preferably, power supply is started in the order of the processing, that is, the random number generator 13 and the random number memory 14, the registered ID memory 12, and the driving device 10 in this order.

When power supply to the processing control unit 11 is started, the processing control unit 11 detects that a response request signal is being transmitted, and controls the random number generation unit 13 to generate a 24-bit random number X. (Step S4). FIG. 4 is a flowchart showing the contents of random number generation (S4) in the present embodiment.

In the first step S 400, a random number Xk is generated by the random number generator 13 and input to the processing controller 11. In this random number generation, when the random number generation unit 13 is constituted by a 24-bit binary counter, for example, the binary counter is caused to perform a count operation by a predetermined clock signal unrelated to the communication between the transmission / reception units 6 and 9. For example, this is achieved by stopping the binary counter when a response request signal is received from the key device 1 and reading the value. On the other hand, when the random number generation unit 13 is configured by an M-sequence generation circuit, the shift register is operated by a predetermined clock signal irrelevant to the communication between the transmission / reception units 6 and 9 and, for example, the key device 1 The random number can be generated by reading a numerical sequence appearing in the output of the shift register within a predetermined period after receiving the response request signal.

In step S401, the comparison means 21 sequentially compares the generated random number Xk with the previous random numbers Xk-1, Xk-2,... In the random number memory 14. As a result of this comparison, if the latest random number Xk matches one of the previous random numbers Xk-1, Xk-2,..., The output control means 22 receiving this result prohibits the output of the random number Xk. (Step S404), generation of a random number Xk again (Step S400), comparison of random numbers (Step S401), determination (Step S402), and random number Xk so that duplicate random numbers do not always occur for a predetermined number of times.
(Step S404) is repeated. On the other hand, if all the previous random numbers in the random number memory 14 do not match ("No" in step S402), the output control means 22 receiving the result permits the output of the random number Xk (step S403). The random number generation processing S4 ends.

Returning to FIG. 2, in the next step S5, the random number X generated by the processing control section 11 is output to the transmitting / receiving section 9 for 30 msec, for example, as shown in FIG. Let the device 1 transmit. The control for preventing the duplication of the random numbers shown in FIG. 4 and described above is performed immediately after this step S5 in preparation for the next random number generation, and after checking the duplication with the previous random numbers in advance by the procedure of FIG. It is good also as a structure which performs. As shown in FIG. 2, in a serial process of generating a random number and transmitting a random number signal after receiving the response request, the response request is received because the random number generation may be continuously repeated. The time at which a random number signal is sent fluctuates. If the random numbers are stored in advance as described above, a means for storing the random numbers is necessary, but the random number is repeatedly generated during another processing period, so that the processing time varies. Therefore, there is an advantage that the timing design of the system is facilitated.

When the transmission / reception unit 6 of the key device 1 receives this random number signal (step S6, see FIG. 3B), the transmission / reception unit 6 extracts the random number X from the received random number signal and sends it to the signal processing unit 5. send. In the next step S7, the signal processing section 5 reads out the specific identification code IDS recorded in advance in the ID memory 7, and reads out a predetermined or arbitrarily selectable function f from another memory or the like. This function f
However, if a specific example is given here, when the corresponding two bits are the same “1” or “0”, the 2
It is possible to use a so-called exclusive-OR logical operation function in which both bits are set to "1" and when they are different, both bits are set to "0".

Then, in the following step S8, the read specific identification code IDS is encrypted (logically operated) using the random number X and the function f and scrambled. By this encryption, as shown in the example in the following table, the specific identification code ID
An encrypted code f (X, IDS) of S can be generated.

[Table 1]

The generated encrypted code f (X, IDS)
Is transmitted as an encrypted ID signal to the lock device 3 within a predetermined time of, for example, 30 msec, as shown in FIG. 3A (step S9).

When the lock device 3 receives this encrypted ID signal (step S10, see FIG. 3D), the encrypted ID signal is decrypted, and the encrypted code f
(X, IDS) is sent to the decoding unit 18 in the processing control unit 11, and decoding is performed in the subsequent step S11, that is, the original specific identification code IDS is derived by a logical operation or the like. More specifically, the decryption unit 18 reads in advance a decryption function f ^-1 corresponding to the function f from a predetermined memory, and uses the function f ^-1 and the previously transmitted random number X to input the decryption function. A logical operation is performed on the conversion code f (X, IDS) to obtain the original specific identification code IDS. In addition, as shown in the above [Table 1],
When a logical operation function f of exclusive OR is used for encryption,
If the exclusive OR operation is performed twice, it returns to the original state, so that the logical operation function f ^-1 for decryption is the same as the function f used for encryption here.

In step S12, the collating unit 19 in the processing control unit 11 sequentially collates the decrypted specific identification code IDS with a plurality of registered identification codes IDR stored in advance in the registered ID memory 12, and transmits the same. It is checked whether or not the specified identification code IDS has been registered.

The matching method of the identification code is such that all the registered identification codes IDR stored in the registered ID memory 12 are set to 1
A method of sequentially collating with the specific identification code IDS may be used from the first, but here, a more efficient collation method and a code record therefor will be described. FIG. 5 is an explanatory diagram showing a format configuration of the specific identification code IDS and the registered identification code IDR (hereinafter, both are simply referred to as “identification codes”). FIG. 6 is a diagram in which the identification codes are systematically arranged to facilitate the search for the identification codes. It is assumed that the identification code is 16 bits for convenience only in this format description. 24 as described above
For identification codes of other bit numbers such as bits,
The basic format configuration and collation method are the same as those described below.

The identification code illustrated in FIG. 5 is a main group ID composed of three sections, that is, upper 4 bits.
It comprises a code (MID), a subgroup ID code (SID) composed of the next 4 bits, and an individual ID code (IID) composed of the lower 8 bits.
For example, in a keyless entry system for an entrance door of an apartment house, MID corresponds to a residential building, SID corresponds to a floor, and IID corresponds to a code indicating each entrance door. Further, the systematic layout diagram illustrated in FIG. 6 is a so-called hierarchical layout structure, in which different codes (for example, SID0 and SID1) in the same hierarchy (section) on the higher side immediately lower in level. The same number of codes are repeatedly arranged in the same order (for example, the same individual codes IID0 to IID255 are repeatedly arranged immediately below SID0 and SID1 immediately below). In the registration ID memory 12, systematic code recording as shown in FIG. 6 is performed so that the recorded code can be searched systematically.
For example, if the 16-bit registered identification code IDR is recorded from the first address in the memory in ascending or descending order, the systematic arrangement as shown in FIG. 6 is realized naturally. Further, the SIDs may be arranged in ascending order of the number of MIDs.

FIG. 7 shows an example in which the registered identification code IDR is searched from the top to the bottom in FIG. 5 and is compared with the specific identification code IDS.
6 is a flowchart showing the procedure in detail. First, in step S120, the MI of both identification codes IDR and IDS is determined.
D0 are compared with each other, and it is determined in step 121 whether they match. If they do not match, the search target is shifted by one in step S122, and the matching of MIDm (m = 0 to 15) is repeated until they match. When it is determined in step S121 that the MIDs match, the SIDs (s = 0 to 15) are similarly collated (step S123), matched (step S124), and incremented s (step S121).
125) is repeated until it is determined that matching SIDs exist. Then, for IIDi (i = 0 to 225), the collation and the match determination are repeated in the same manner (steps S126 to S128). If all codes are searched and collated in each layer (section) and no match is found, the processing is terminated at that point and the operation control itself such as locking / unlocking is forcibly terminated. Then, the process returns to the same intermittent operation as before the response request.

By such an ID code collation method, efficient collation can be achieved without waste in retrieval. For example,
If a 4-bit microcomputer is used for the processing control unit 11 and the length of the identification code is defined as 16 bits by the system format, assuming that the time required for 4-bit code verification is 10 μsec, all the identification codes are Approximately 40 μsec ~
It takes 2.6 seconds. On the other hand, when collation is performed for each layer (section) in the identification code by the above-described method, it takes only about 40 μsec to 5.5 msec, and the time required for collation is greatly reduced.

FIGS. 5 and 6 merely illustrate the classification of the identification code and the hierarchical structure.
There are no limitations on the number of bits in each section, the number of codes that can be taken in each section, and the like. Further, there is no limitation on the arrangement of the hierarchies shown in FIG. 6. Further, the procedure of the collation is not limited, and it is generally preferable to sequentially perform the collation from the upper side having the smaller number of bits and the type of the code. For example, if the number of bits of the individual ID code IID is extremely small and the collation is easy, The collation may be performed first from the individual ID code IID.

As a result of this collation, if there is a registered identification code IDR that matches the decrypted specific identification code IDS, the processing control section 11 opens the door included in the previously transmitted response request signal. Alternatively, a door drive signal is output to the door 2 from, for example, the collation unit 19 in accordance with the “close” command signal. As a result, the door is opened and closed. Simultaneously with the opening / closing control of the door, when a drive signal of a lock for instructing unlocking to open the door and unlocking to close the door is output from the collating unit 19 to the drive device 10, for example, the drive signal is output. The door is unlocked or locked by the received drive device 10 (step S13).

In this example, each time the door is opened and closed, a random number X is generated by the lock device 3 and the specific identification code IDS is encrypted in the key device 1 using the received random number signal. Since f (X, IDS) is transmitted to the lock device 3, the signals spatially transmitted in both directions are always different signals, and even if a signal is intercepted during transmission, there is no danger of the specific identification code IDS being stolen. .

In this example, when the power supply control unit 11 controls the power supply start timing during the intermittent operation, the power supply to the transmission / reception unit 9 is controlled by the other parts 10-1.
4 and the reception state is quickly adjusted. For this reason, as in the conventional case, if power is supplied to all the parts at the same time, the processing control unit 11 and the like can perform processing, but it takes time to start up the transmission and reception unit 9 and wastes time. Nothing. As a result, the steady operation time for performing a series of process control for locking / unlocking is shortened by that much, and power saving can be achieved. In addition, the response is good.

In this example, the same random number is prevented from being used for encrypting the specific identification code IDS continuously for a predetermined number of times, and there is an advantage that a system with high security can be realized. In this case, the probability that the code of the signal coincides by chance does not change regardless of how many times it is performed. The probability that this code matches is always about 1 / 6.7 million when the signal is composed of, for example, a 24-bit code, and extremely high security can be easily realized.

Also, in this example, the systematic identification code ID
Since the registration of R is performed and the collation with the specific identification code IDS can be efficiently performed for each section, not only power saving is achieved, but also the time for actually performing the locking / unlocking operation after issuing the instruction. , Short response, high responsiveness, and good usability.

Second Embodiment FIG. 8 is a block diagram showing a schematic configuration of a lock device in a keyless entry system according to the present embodiment. In the present embodiment, the configuration of the random number changing unit in the lock device is different from that of the above-described first embodiment, and the other parts are the same. The same parts are denoted by the same reference numerals, and description thereof will be omitted. Specifically, the configuration and operation of the key device 1 (not shown) are not different from those of the first embodiment. As for the lock device 3, the transmission / reception unit 9, the drive device 10, the registration ID memory 12, the random number generation unit 13, the random number memory 14, the battery 1
5. The configurations and operations of the power control unit 16 and the timer 17 are the same as those of the first embodiment. Further, the entire processing procedure shown in FIG. 2 and the processing timing shown in FIG.
Are the same as those in the first embodiment.

In the lock device 30 of the present embodiment, having the random number changing unit 32 in the processing control unit 31
This is the same as the first embodiment. This random number changing unit 32 is different from the random number changing unit 20 of the first embodiment in that an arithmetic processing unit 33 for performing predetermined arithmetic processing is provided instead of the output control unit 22 in FIG. As this calculation processing,
Any arithmetic processing that can always generate a different random number may be used. For example, “0” and “1” of all bits constituting the random number Xk
Corresponds to the operation of inverting.

FIG. 9 is a flowchart showing the contents of random number generation (S4 in FIG. 2) in the lock device 30. In steps S410 to S412, similarly to steps S400 to S402 in the first embodiment (FIG. 4), the random number generation unit 13 generates the random number Xk (step S41).
0), the latest random number Xk and the previous random number X by the comparing means 24
., Xk-2,... (step S411) and determination (step S412). If the result of this determination is that the latest random number Xk matches one of the previous random numbers Xk-1, Xk-2,...
After performing a predetermined operation on the random number Xk to change the random number to a different random number, and outputting the changed random number as Xk (step S413), the random number generation processing S4 ends.

According to the second embodiment, similar to the first embodiment, the same random number is continuously generated a predetermined number of times by the specific identification code I.
It is possible to avoid being used for DS encryption and realize a system with high security. Also, in this example, two-way communication of different signals can be performed so that there is no danger of the identification code being stolen, there is no useless operation time associated with the intermittent operation, and efficient verification of the identification code is achieved. Thus, there is an advantage similar to that of the first embodiment, such as low power consumption and good responsiveness.

In particular, as an effect unique to the present embodiment, in the processing for preventing the duplication of random numbers (random number change processing), it is not necessary to check the duplication of random numbers in advance and stock them. A different random number can always be obtained by the arithmetic processing, and there is an advantage that the timing design for the random number processing of the system is easy.

[0056]

According to the identification signal matching apparatus and the identification signal matching method of the present invention, when a random number used for encryption is generated, the random number is duplicated with a predetermined number of random numbers output in the past and the latest. Even if the same random number is repeatedly generated until it no longer overlaps, or is always output as a different random number by arithmetic processing and used for encryption, it is possible to effectively prevent the same random number from being repeatedly transmitted within a predetermined number of times. You. For this reason, the randomness of the identification code encrypted by the random number is further increased, and the security is improved. For example, an outsider who has obtained identification code information transmitted continuously tries to extract the encryption procedure by intercepting the transmission signal, and it is difficult to extract the encryption procedure due to the high randomness of the transmission signal. Become.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of an identification signal matching device (keyless entry system) according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing the operation of the keyless entry system of FIG.

FIG. 3 is a timing chart showing transmission / reception and intermittent operation in the keyless entry system of FIG. 1;

FIG. 4 is a flowchart showing the contents of random number generation (S4 in FIG. 2).

FIG. 5 is an explanatory diagram showing a format configuration of an identification code.

FIG. 6 is a diagram in which identification codes are systematically arranged in order to facilitate retrieval of registered identification codes.

FIG. 7 is a flowchart showing a procedure of ID code comparison (step S12) in FIG. 2 in a case where a registered identification code is searched from the top to the bottom in FIG. 6 and compared with a specific identification code.

FIG. 8 is a block diagram illustrating a schematic configuration of a lock device of an identification signal matching device (keyless entry system) according to a second embodiment of the present invention.

9 is a flowchart showing the contents of random number generation (S4 in FIG. 2) in the keyless entry system in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Key device (detected device), 2 ... door, 3, 30 ... Lock device (detection device), 4 ... Switch part, 5 ... Signal processing part, 6 ...
Transmitting / receiving section, 7: ID memory, 8: battery, 9: transmitting / receiving section,
DESCRIPTION OF SYMBOLS 10 ... Drive device, 11, 31 ... Processing control part, 12 ... Registration ID memory (storage part), 13 ... Random number generation part, 14 ... Random number memory, 15 ... Battery, 16 ... Power supply control part, 17 ... Timer, 18 ... Decoding unit, 19: collating unit, 20, 32: random number changing unit, 21: comparing unit, 22: output control unit, 33: arithmetic processing unit, IDS: specific identification code, IDR: registration identification code, MID: main group ID Code, SID
... subgroup ID code, IID ... individual ID code,
X: random number.

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI H04Q 9/00 311 H04L 9/00 641

Claims (7)

[Claims] An apparatus for encrypting and transmitting a first identification signal can transmit and receive a signal wirelessly between the apparatus to be detected and the apparatus to be detected, and determines whether the apparatus to be detected is registered in advance. A detection device for identifying whether or not the detection device has a random number generation unit that generates a random number used for the encryption, and outputs the generated random number to the device to be detected as a random number signal. An identification signal matching device for decrypting a first identification signal and comparing a first identification signal before encryption obtained by the decryption with a second identification signal stored in advance, wherein the random number generation unit A random number output from the storage unit that stores a predetermined number of random numbers counted from the output in the newest order; and monitors the random number output from the random number generation unit and the random number in the storage unit, and there is a matching random number. When the match Wherein a random number replaced by the different random identification signal checking apparatus and a random number changing section for transmitting to the apparatus to be detected. 2. The random number changing section, comprising: comparing means for sequentially comparing the random number output from the random number generating section with the random number in the storage section; and when the comparing means determines that the random numbers match, the random number generating section generates the random number. 2. An output control unit for controlling a generation and an output of the random number repeatedly while prohibiting transmission to the device to be detected until the comparing unit determines that there is no coincident random number. Identification signal matching device. 3. The random number changing unit compares the random number output from the random number generation unit with the latest random number in the storage unit. When the comparison unit determines that the random numbers match, the random number changing unit matches the random number. The identification signal matching device according to claim 1, further comprising: an arithmetic processing unit configured to perform predetermined arithmetic processing on the random numbers and generate the different random numbers. 4. The arithmetic processing performed by the random number processing means,
The identification signal matching device according to claim 3, wherein the process is a process of inverting all bits of the binarized code of the matched random number. 5. A method for generating and outputting a random number, encrypting a first identification signal using the output random number, and transmitting the encrypted first identification signal;
The receiving side decrypts the transmitted first identification signal, reads out the first identification signal before encryption, and compares it with a second identification signal registered in advance. Of the random numbers used for the encryption, a predetermined number of random numbers are always stored by counting the output in the new order, and when outputting a new random number, the new random number and the stored random number are monitored. Then, when a matching random number exists, the matching random number is replaced with a different random number, and the identification signal matching method is used for the encryption. 6. The newly generated random number is compared with the stored random number. If there is a random number that matches according to the comparison result, the encryption is performed until the random number no longer matches. 6. The identification signal collating method according to claim 5, wherein the generation and output of the random number are repeatedly controlled while prohibiting an output for use in the identification signal. 7. A method for comparing the newly generated random number with the stored random number, and when there is a random number that matches according to the comparison result, performs a predetermined arithmetic process on the random number that matches. The identification signal matching method according to claim 5, wherein a different random number is generated.