JPH08228390A - Method and system for remote control - Google Patents

Abstract

PURPOSE: To disable a user from releasing arming by copy of a remote control signal. CONSTITUTION: In a remote control unit, a cyclic code generator 3b generates the cyclic code, which is shifted from the preceding cyclic code by random numbers generated by a random data generator 3g, by the key operation, and a computing element 3d generates a secret code corresponding to the cyclic code and the secret code is added to the command code outputted from a command code generation part 3e in accordance with the operation key, and the remote control signal is sent from a transmission part 5. When receiving the signal, a security device generates one cyclic code and compares it with the cyclic code decoded by the secret code in the reception signal and executes the operation corresponding to the command code in the case of equality but successively generates the cyclic code in the case of inequality. When equality is attained before a prescribed number of cyclic codes are generated, the operation corresponding to the command code is executed; but if it is not attained regardless of generation of the prescribed number of cyclic codes, this operation is not executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote control method and its control system, and more particularly to a remote control method and its control system which cannot be abused even if a remote control signal is intercepted and analyzed.

[0002]

2. Description of the Related Art In recent years, vehicle mischief and theft cases have frequently occurred due to the deterioration of public safety, and car security systems for countering these cases have been rapidly spread. The car security system can lock (arming) and unlock (disarming) the door with a hand-held operation device (remote control unit) owned by the driver, and at the same time, activates a security device installed in the vehicle to bring it into a security operation state. It is a thing. When someone opens the door or shakes the vehicle to steal the car or mischief the car during security operations, these are detected by sensors and an alarm is sounded or the headlights blink. Or repel thieves. Also, when a legal driver operates the disarming key of the remote control unit to get in the car, the security operation is automatically stopped and the lock is released.

That is, the car security system is
When the driver gets out of the vehicle, closes the door, and presses the arming key of the remote control unit, the remote control unit modulates a carrier wave with a digital remote control signal including an individual code and an arming code (command code) and emits a radio wave. . The security device installed in the vehicle receives the radio wave emitted from the remote control unit and demodulates it, and then compares the individual code included in the received signal with the individual code set in the device in advance, and matches them. Arming code (locking operation) based on the arming code
And the car security operation is started.

In this anti-theft state (arming state), the car security device monitors the occurrence of an abnormality based on the outputs of various sensors such as a door opening / closing sensor, a motion sensor and a shock sensor. For this reason, for example, during arming, when a thief steals the vehicle or moves into the vehicle in order to move the vehicle, the motion sensor detects this, sounds an alarm, and turns on the headlights. Flash or repel thieves.

On the other hand, when the driver returning to the vehicle depresses the disarming key of the remote control unit, the remote control unit will display the individual code, as in the case of the arming key.
A carrier wave is modulated by a digital remote control signal including a disarming code (command code) and a radio wave is emitted. The security device installed in the vehicle receives and demodulates the radio waves emitted from the remote control unit, and after that,
The individual code included in the received signal is compared with the individual code preset in the device, and if they match, the antitheft state is released, and the disarming operation (unlocking operation) is executed.

As described above, the car security system has the convenience of being able to simply lock and unlock the door with a remote controller, and in addition, a thief can try to move the vehicle, lift the vehicle, shake the vehicle, close the door, It has an excellent function of issuing an alarm and repelling when the trunk is opened or the glass is broken.

Further, the car security system has an advantage that arming and disarming cannot be performed unless the remote control unit has the same individual code as the individual code registered in advance in the in-vehicle security device.

[0008]

However, in the conventional car security system that executes arming / disarming only by matching individual codes, a malicious third party who tries to invade or steal an automobile is attempted. There was a defenseless side. For example, a device is commercially available that can copy a radio wave of a predetermined radio frequency as it is for a certain period of time and retransmit it. If a wireless signal (remote control signal) at the time of disarming is copied using such a device, a third party can emit the copied remote control signal from the device to cancel the car security operation even when the car security operation is in progress. Can easily break into a car.

In order to solve the above problem, the secret code added to the command code, that is, the cyclic code is changed every time the command code is transmitted, and the remote control signal in the previous operation is copied. A method has been developed to improve security performance by making the cyclic code of the copy signal not match the cyclic code sent by the next key operation, but when considering the near future, analysis that is familiar with information theory etc. It is expected that a person or the like will appear, and when the person acquires a code for several consecutive times, the lock itself that generates the secret code may be analyzed. Further, when the computer and the code transmitter / receiver are combined by using this lock, there is a possibility that the lock may be unlocked. This is because the generated code has a certain degree of regularity and therefore has the possibility of analysis.

In view of the above, the object of the present invention is to prevent the vehicle from being disarmed during the security operation even if the remote control signal is copied or the secret code is analyzed, thereby preventing the theft or theft of the vehicle. A remote control method and its system are provided. Still another object of the present invention is to provide a remote control method, a remote control system, and a remote control by the remote control unit, in which a controlled device cannot be remotely controlled only by copying and firing a remote control signal or analyzing a secret code. To provide a controlled device.

[0011]

According to the present invention, there is provided a remote control unit for transmitting a command code according to the operated key, the remote control unit having a key for remotely controlling the device, and transmitting from the remote control unit. In a remote control method in a remote control system including a controlled device that executes an operation according to the command code, a cyclic code generator that generates cyclic codes in the same order is provided to both the remote control unit and the controlled device. When a key is operated, the remote control unit generates one cyclic code, which is a random number advanced from the cyclic code generated last time, from the cyclic code generator, and generates the cyclic code or a code corresponding to the cyclic code as a secret code. As a code, it is sent by adding it to the command code corresponding to the operation key. Upon receiving a signal from the unit,
One cyclic code is generated from the cyclic code generator, a cyclic code is obtained from the secret code in the received signal, the cyclic code on the remote control unit side is compared with the cyclic code generated on the controlled device side, and they match. If there is a mismatch, the operation according to the command code sent from the remote control unit is executed, and if they do not match, a cyclic code is sequentially generated, and it is checked whether the cyclic code matches the cyclic code on the remote control unit side, and the predetermined When a match is obtained before the number of cyclic codes is generated, the operation according to the command code is executed, and when the match is not generated even when the predetermined number of cyclic codes is generated, the operation according to the command code is not executed. This can be solved by taking a characteristic remote control method.

In the preceding paragraph, the individual code is stored in both the remote control unit and the controlled device, and the remote control unit applies the individual code to the cyclic code generated by the cyclic code generator to create a secret code. ,
The controlled device can solve the problem by causing the individual code held by itself to act on the secret code to decode the cyclic code on the remote control unit side.

Further, in the preceding two paragraphs, the above-mentioned problem is that the individual code is stored in both the remote control unit and the controlled device, and the remote control unit applies the individual code to the cyclic code generated by the cyclic code generator. To create a secret code, add the secret code and the individual code to the command code and send it, the controlled device applies the individual code held by itself to the secret code to decode the cyclic code on the remote control unit side, When the received individual code matches the individual code held by itself, and when the decoded cyclic code and the cyclic code generated on the controlled device side match, it is solved by executing the operation according to the command code. be able to.

Further, the above-mentioned problem is to provide a remote control unit which is provided with a key for remotely controlling the apparatus and which sends a command code according to the operated key, and an operation according to the command code sent from the remote control unit. In a remote control method in a remote control system having a controlled device for executing, the remote control unit includes a memory for storing a cyclic code generated last time and a random data generator for generating a random number when a key is operated. A cyclic code generator for generating one cyclic code advanced by a random number generated from the random data generator with reference to a previously generated cyclic code stored in a memory when a key is operated; A secret code is generated using the cyclic code output from the generator. The controlled device includes a let code generation unit, a remote control signal generation unit that generates a remote control signal including a command code and a secret code according to the operated key, and a remote control signal transmission unit that transmits the remote control signal, and the controlled device includes: A cyclic code generator that generates cyclic codes in the same order as the cyclic code generator provided in the remote control unit, and a cyclic code reproduction unit that reproduces the cyclic code from the secret code included in the remote control signal sent from the remote control unit. A comparing unit that compares the cyclic code generated from the cyclic code generator by receiving the remote control signal from the remote control unit with the cyclic code on the remote control unit side;
When they match, the operation according to the command code sent from the remote control unit is executed, and when they do not match, the cyclic code generator sequentially generates the cyclic code, and the comparison unit determines that the cyclic code is remote control. If it matches with the cyclic code on the unit side, and if there is a match before the predetermined number of cyclic codes is generated, the operation according to the command code is executed, and if the predetermined number of cyclic codes are generated, no match is found. Can be solved by using a remote control system having an operation control unit that does not execute an operation according to the command code.

[0015]

When the key is operated, the remote control unit causes the cyclic code generator to generate a cyclic code shifted by a random number generated from the random data generator, and to generate the cyclic code or a code corresponding to the cyclic code as a secret code. When a signal is received from the remote control unit, the controlled device generates one cyclic code from the cyclic code generator and sends it as a secret code in the received signal. The cyclic code is further decoded, the decoded cyclic code on the remote control unit side is compared with the cyclic code generated on the controlled device side, and if they match, the operation according to the command code sent from the remote control unit is performed. If it does not match, the cyclic code is sequentially generated, and the cyclic code is the cyclic code on the remote control unit side. Checks for a match.When a match is obtained before the predetermined number of cyclic codes are generated, the operation according to the command code is executed. No action is taken.
By doing this, the secret code (cyclic code) added to the code changes randomly each time the command code is transmitted, so even if the remote control signal at the time of the previous disarming is copied or analyzed. , A matching cyclic code cannot be obtained. Therefore, a malicious third party cannot cancel the arming, the security performance can be improved, and the intrusion and theft into the automobile can be effectively prevented.

The remote control unit applies the individual code to the cyclic code generated by the cyclic code generator to create a secret code, adds the secret code and the individual code to the command code, and sends the command code. Applies the individual code held by itself to the secret code to decode the cyclic code on the remote control unit side, and the received individual code matches the individual code held by itself,
When the decoded cyclic code matches the cyclic code generated on the controlled device side, the operation corresponding to the command code is executed. By doing so, the security performance can be further improved.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention proposes a method and system in which analysis is not possible by eliminating the regularity of the transmitting side, and FIG. 2 shows an overall configuration diagram of a car security system according to the present invention. In the figure, 1 is a remote control unit,
Reference numeral 2 is an operating section provided with an arming key 2a, disarming key 2b and the like, 3 is a remote control signal generating circuit for creating and outputting a 1-frame remote control signal including a command code corresponding to the operated key, 4 is a remote control signal A modulation circuit 5 for modulating a carrier wave according to a predetermined modulation method such as ASK modulation, FSK modulation, etc. on the basis of is a transmission circuit for inputting a modulation signal, further performing frequency conversion and power amplification, and transmitting from the antenna 6.

The remote control signal generation circuit 3 includes a cyclic code generator 3b for generating a cyclic code, and when a key is operated, one cyclic code is generated from the cyclic code generator 3b together with a random data generator described later. , The cyclic code or a code corresponding to the cyclic code is generated as a secret code. Then, the secret code is added to the command code corresponding to the operation key to generate and output a digital remote control signal.

Reference numeral 10 is an in-car security device, 15 is a receiving antenna, 16 is a receiving circuit for performing high frequency amplification and frequency conversion of the received signal, 18 is a demodulation circuit for demodulating a digital remote control signal from the received signal, 20 Is a security controller that executes security control based on a remote control signal, 21 is a door sensor, 22 is a door lock device, 23 is a siren drive circuit, 24 is a headlamp blink circuit, 25 is a motion sensor, 26 is a shock sensor, and 27 is glass. It is a sensor.

The security controller 20 is provided with a cyclic code generator 20e for generating a cyclic code, and when receiving a remote control signal from the remote control unit 1, generates a cyclic code from the cyclic code generator 20e and at the same time receives the received signal. The cyclic code is decoded from the secret code, and the decoded cyclic code on the remote control unit side and the cyclic code generated on the controlled device side are compared. If they match, the command sent from the remote control unit 1 The operation according to the code is executed, and if it does not match, it is controlled not to be executed. When the arming is instructed, the security controller 20 starts arming, starts the security operation, and opens the door to steal the car by another person (thief) or perform mischief during the security operation. When it shakes, these are detected by a sensor, an alarm is sounded, or a headlamp blinks to repel it.

FIG. 1 is a detailed configuration diagram of the remote control unit, and the same portions as those in FIG. 2 are designated by the same reference numerals. In the remote control signal generation circuit 3, reference numeral 3a denotes an individual (ID) code generator 3b which stores an individual code in a ROM and generates the code appropriately.
Is 1 together with the random data generator described below
A cyclic code generation unit for generating a cyclic code, 3c is a cyclic code memory for storing the previously generated cyclic code, 3d is a secret for executing a predetermined operation using the cyclic code and the individual code to generate a secret code SCD. Code generator (arithmetic unit), 3e is a command code CM corresponding to an operated key such as an arming key or a disarming key.
A command code generation unit 3f for generating a CD is a remote control signal generation unit for generating and outputting a remote control signal of one frame by adding an individual code and a secret code to the command code.

Reference numeral 3g is a random data generator, and each time a command code generator 3e generates a command code by operating a key such as an arming key or a disarming key, it is relatively small, for example, about 1, 2 or 3. A random positive integer is randomly generated and sent to the cyclic code generator 3b.

FIG. 3 is a frame configuration diagram of a remote control signal, which is composed of idling data, frame synchronization data, an individual code, a command code, and a secret code. The idling data changes the microcomputer operation from the sleep mode to the high speed operation mode. When the idling data is received, the microcomputer which was in the sleep state shifts to the high speed mode.

FIG. 4 is a block diagram of the cyclic code generator 3b, showing n stages (n = 16) of flip-flops FF _{01 to} FF.
₁₆ and (n-1) exclusive OR circuits EXOR _{01 to} EX
A switch section S for inputting the output of OR ₁₅ and the final stage flip-flop FF ₁₆ to predetermined EXOR ₀₁ to EXOR _15.
The cyclic code can be changed depending on which exclusive OR circuit the output of the flip-flop FF ₁₆ is input to. Cyclic code generator 3b is predetermined trigger signal, proceeds e.g. key operation signal and the contents of the flip-flop FF ₀₁ to ff ₁₆ by the output signal of the random data generator (cyclic code) one or more, each flip-flop FF
_A predetermined cyclic code is output from _{01 to} FF ₁₆ . The cycle of the cyclic code is tens of thousands, and once every tens of thousands,
The same cyclic code appears.

FIG. 5 is a block diagram of the cyclic code generator used in the present invention. The output of the flip-flop FF _{16 at} the final stage is connected to the exclusive OR circuits EXOR ₀₃ , EXOR ₁₂ , EXOR.
₁₄ has the configuration returned to. This cyclic code generator shifts the content to 1001 0010 1110 0000 when a key operation signal is generated when the content is 1010 0100 1101 0001, and outputs the content as a cyclic code. Thereafter, the contents are shifted each time a key operation signal or the like is generated, and the cyclic codes are sequentially output one by one.

FIG. 6 is a block diagram of the security controller 20 in the security device 10. 20 in the figure
Reference numeral a denotes a synchronization detection / data separation unit that receives the demodulated signal output from the demodulation circuit 18 in FIG. 1 and detects the synchronization to separate the command code, the individual code, and the secret code. Reference numeral 20b is an individual code generator for registering a plurality of individual codes in advance so as to correspond to a plurality of remote control units and outputting a predetermined individual code as appropriate, and is provided with a ROM for storing the individual codes. Reference numeral 20c is an individual code collating unit for checking whether the individual code sent from the remote control unit matches one individual code registered in the ROM of the individual code generating unit. 20
Reference numeral d is a cyclic code decoding unit that decodes the cyclic code on the remote control unit side by applying an individual code to the secret code sent from the remote control unit.

Reference numeral 20e is a cyclic code generator, which has the same configuration as the cyclic code generator (FIG. 5) on the remote control unit side and outputs the cyclic code in the same order. Reference numeral 20f denotes a cyclic code collation code memory, which stores the latest cyclic code output from the cyclic code generator 20f for collation in association with each individual code. 20g is a cyclic code C on the remote control unit side output from the cyclic code decoding unit 20d.
A comparing unit for collating the cyclic code CCD _U output from the CD _R and the cyclic code generator 20e. Reference numeral 20h is an operation control unit that executes an operation according to a command sent from the remote control unit when the individual codes match and the cyclic codes match.

Next, the overall operation will be described. When a predetermined operation key of the remote control unit 1, for example, a disarming key is operated, the cyclic code generation unit 3b reads the cyclic code generated last time from the cyclic code memory 3c and sets it in each flip-flop FF _{01 to} FF ₁₆ (FIG. 5). To do.

The random data generator 3g randomly generates a positive integer of about 1 to 3 in response to a key operation and sends it to the cyclic code generator 3b. Then, the cyclic code generation unit 3b advances the content by the sent random number to generate a cyclic code CCD _R , inputs the cyclic code to the secret code generator 3d, and stores it in the cyclic code memory 3c.

The secret code generator 3d executes a predetermined operation using the cyclic code CCD _R and a preset individual code to generate a secret code SCD. After that, the remote control signal generator 3f outputs the command code corresponding to the operation key output from the command code generator 3e, in this case, the disarming code CMCD, the individual code ICD and the secret code S.
A CD is added to create a remote control signal having the frame structure shown in FIG. The modulator 4 modulates the carrier wave with the remote control signal and frequency-converts it, and the transmitter 5 amplifies the power and radiates it from the antenna 6.

Receiving circuit 1 of vehicle-mounted security device 10
Reference numeral 6 applies high frequency processing such as high frequency amplification and frequency conversion to the transmission signal from the remote control unit captured by the antenna 15, and the demodulation circuit 18 demodulates digital remote control data and inputs it to the security controller 20.

In the security controller 20,
The synchronization detection / data separation unit 20a (FIG. 6) performs synchronization detection based on the synchronization data included in the demodulated remote control data, and outputs a command code (disarming code).
FCD, individual code ICD, secret code SCD
Is output separately.

The individual code collation unit 20c receives the received individual code and the individual code generation unit 20b ROM (not shown).
It is checked whether or not it matches a predetermined code registered in advance, and the result of matching or mismatching is notified to the operation control unit 20h. In the case of a match, the cyclic code is stored in the memory corresponding to the individual code.

Since the cyclic code CCD _R on the remote control unit side is advanced by the random number generated by the random data generator 3g to generate the cyclic code CCD _R as described above, the comparison results do not match. Absent.

Therefore, by the processing as shown in the flowchart of FIG. 7, the cyclic codes are made to match when the operation is performed with the proper remote control unit. The cyclic code decoding unit 20d applies the individual code ICD 'output from the individual code generating unit 20b to the secret code SCD to perform a predetermined operation to decode the cyclic code CCD _R (step 101). On the other hand, the cyclic code generator 20e makes the cyclic code matching memory 2 correspond to the input individual code.
The latest collation cyclic code (cyclic code used for the previous collation) stored in 0f is read out and set in the built-in flip-flops FF _{01 to} FF ₁₆ , and N is initialized to 0 (step 102). Then, the cyclic code generator 20e shifts the content by one to generate the next cyclic code CCD _U (step 103), and inputs the cyclic code CCD _U to the comparison unit 20g.

The comparator 20g compares the decoded cyclic code CCD _R on the remote control unit side with the cyclic code CCD _U output from the cyclic code generator 20e (step 10).
4) Input the match / mismatch to the operation control unit 20h.

If they match, the cyclic code is stored in the memory 20f (step 104 ') and the fact is notified to the operation control section 20h to end the comparison operation. If they do not match, N is incremented ( N + 1 → N, step 105), and then it is checked whether N exceeds a set value, for example, 100 (step 106), and if it exceeds 100, it is considered that the remote controller is not properly used, and the process ends. But,
If N ≦ 100, the process returns to step 103 and the subsequent processing is repeated.

The operation control unit 20h has the same individual code,
If the cyclic codes match, the command code (disarming code) CMCD is recognized as a valid remote control operation and stored in the memory 20f corresponding to the individual code, that is, the disarming record. Based on the above, the security operation is released, and then the door lock is released. On the other hand, if the individual codes do not match, or if the cyclic codes do not match, it is recognized as an illegal remote control operation and the operation corresponding to the command code CMCD is not executed. That is, the security operation is not canceled and the lock is not released. Also, the memory 20f is not rewritten.

With the above arrangement, every time the command code is transmitted by the key operation, the secret code (cyclic code) added to the code changes randomly.
Even if the remote control signal at the time of the previous key operation is copied, the cyclic code of the copy signal does not match the cyclic code to be sent by the next key operation, and the code for several consecutive times is acquired and the secret code is obtained. It is also impossible to analyze the lock itself that generates the code.

Next, consider a case where the user erroneously presses (blanks) a key of the remote control unit in an area where the security device 10 cannot receive radio waves from the remote control unit 1. Even in such a case, the present invention can be dealt with by the contents described above. That is, if the number of blank hits is within a predetermined number of times, the operation explained in the flowchart of FIG. 7 is performed, and when the valid remote control unit is operated, the operation is instructed so that the cyclic codes match. You can

In this case, the security device 10 side sets the upper limit of the number of shifts to be collated in order to secure the blank ejection permissible value, (minimum blank ejection permissible value) × (random shift number upper limit value).
= By setting the number of collation shifts, it becomes possible to cope with both normal use and blank driving.

With the above arrangement, the security device 1
Even if the key of the remote control unit 1 is idled a predetermined number of times outside the receivable area of 0, if a key operation is performed within the reception area, a predetermined operation corresponding to the key can be executed. In this case, since the cycle of the cyclic code is tens of thousands, even if a predetermined number of cyclic codes are generated, they do not match the cyclic code included in the copy signal transmitted by the malicious third party.

The random data generator 3g may be composed of a counter that rotates only while a key is pressed.

[0044]

As described above, according to the present invention, every time a command code is transmitted, the secret code (cyclic code) added to the code is changed without any regularity.
Even if you copy the remote control signal at the time of the previous operation, or if you try to analyze the lock itself that generates the secret code by acquiring the code for several consecutive times,
Since it becomes impossible to match the cyclic codes and the arming cannot be released, the security performance can be improved and the intrusion into the automobile, theft, etc. can be effectively prevented.

Further, according to the present invention, when the cyclic codes on the remote control unit side and the controlled device side do not match, the cyclic code on the controlled device side can be advanced up to a predetermined number of times. As a result, even if the cyclic code on the remote control unit side is ahead of the cyclic code on the controlled device side, the key on the remote control unit is pressed a predetermined number of times outside the reception area of the controlled device (blank strike), and the operation is performed within the reception area. In this case, the cyclic code of the controlled device can be matched with the cyclic code on the remote control unit side, and the remote control can be controlled as instructed. In this case, since the cycle of the cyclic code is tens of thousands, even if a predetermined number of cyclic codes are generated, the cyclic code does not match the cyclic code included in the copy signal transmitted by the malicious third party. Intrusion, theft, etc. can be effectively prevented.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a remote control unit of a car security system of the present invention.

FIG. 2 is an overall configuration diagram of a car security system of the present invention.

FIG. 3 is a frame configuration diagram of remote control data.

FIG. 4 is a configuration diagram of a cyclic code generator.

FIG. 5 is a block diagram of a cyclic code generator used in the present invention.

FIG. 6 is a configuration diagram of a security controller.

FIG. 7 is a processing flowchart of a security controller on the receiving side.

[Explanation of symbols]

 1 Remote Control Unit 2 Operation Section 3 Remote Control Signal Generation Circuit 3a ID Code Generation Section 3b Cyclic Code Generator 3c Cyclic Code Memory 3d Secret Code Generator 3e Command Code Generation Section 3g Random Data Generator 3f Remote Control Signal Generation Section 10 Security Device 20 Security Controller 20e Cyclic code generator

Claims (4)

[Claims] 1. A key for remotely controlling the device,
A remote control method in a remote control system comprising a remote control unit for transmitting a command code according to an operated key and a controlled device for executing an operation according to the command code transmitted from the remote control unit, the remote control unit comprising: A cyclic code generator that generates cyclic codes in the same order is provided in both controlled devices, and when a key is operated, the remote control unit cyclically moves one cyclic code advanced by a random number from the previously generated cyclic code. Generated from the code generator, the cyclic code or a code corresponding to the cyclic code is added as a secret code to the command code corresponding to the operation key and transmitted, and the controlled device receives a signal from the remote control unit, Generates one cyclic code from the cyclic code generator and The cyclic code is obtained from the secret code inside, the cyclic code on the remote control unit side is compared with the cyclic code generated on the controlled device side, and if they match, the operation according to the command code sent from the remote control unit. If there is a mismatch, the cyclic code is sequentially generated, and it is checked whether the cyclic code matches the cyclic code on the remote control unit side. A remote control method characterized by executing an operation according to a command code and not performing an operation according to a command code when a match cannot be obtained even if a predetermined number of cyclic codes are generated. 2. An individual code is stored in both the remote control unit and the controlled device, and the remote control unit applies the individual code to the cyclic code generated by the cyclic code generator to create a secret code, which is controlled. 2. The remote control method according to claim 1, wherein the device applies an individual code held by itself to the secret code to decode the cyclic code on the remote control unit side. 3. The individual code is stored in both the remote control unit and the controlled device, and the remote control unit applies the individual code to the cyclic code generated by the cyclic code generator to create a secret code, and the secret code is generated. The code and the individual code are added to the command code and transmitted, and the controlled device applies the individual code held by itself to the secret code to decode the cyclic code on the remote control unit side, and holds the received individual code and itself The remote control according to claim 1, wherein when the individual codes match and the decoded cyclic code and the cyclic code generated on the controlled device side match, an operation according to the command code is executed. Method. 4. A key for remotely controlling the device,
In a remote control method in a remote control system including a remote control unit that sends out a command code according to an operated key and a controlled device that executes an operation according to the command code sent out from the remote control unit, the remote control unit comprises: , A memory that stores the previously generated cyclic code, a random data generator that generates a random number when the key is operated, and a previously generated cyclic code that is stored in the memory when the key is operated. A cyclic code generator for generating one cyclic code advanced by a random number generated from the random data generator, and a secret code generator for generating a secret code using the cyclic code output from the cyclic code generator. , Command code according to the operated key, seek A remote control signal generation unit for generating a remote control signal including a remote control signal and a remote control signal transmission unit for transmitting the remote control signal, wherein the controlled device has a cyclic code in the same order as a cyclic code generator provided in the remote control unit. And a cyclic code generator that reproduces the cyclic code from the secret code included in the remote control signal sent from the remote control unit,
A comparison unit that compares the cyclic code generated from the cyclic code generator by receiving the remote control signal from the remote control unit with the cyclic code on the remote control unit side, and if they match, the command code sent from the remote control unit In the case of non-coincidence, the cyclic code generator sequentially generates cyclic codes, and the comparison unit checks whether the cyclic code matches the cyclic code on the remote control unit side and generates a predetermined number of cyclic codes. When a match is obtained before, an operation according to the command code is executed, and when a match cannot be obtained even if a predetermined number of cyclic codes are generated, an operation control unit is not executed. A remote control system characterized by that.