JPH08114050A - Remote control device - Google Patents

Abstract

PURPOSE: To restrain the possibility of decoding data being intercepted, small without narrowing the range over which equipment to be controlled can be controlled, by making the transmission outputs of control data high and those of the decoding data low. CONSTITUTION: A transmitter 1 is provided with a control signal transmitting part which transmits control data used to control the action of equipment 15 to be controlled and with a decoding signal transmitting part which transmits decoding data used to decode control signals. A receiver 10 receives and stores the decoding data from the transmitter 1, and receives and decodes the control data according to the decoding data stored, thus controlling the action of the equipment 15 to be controlled. The transmitter 1 of this device is provided with a transmission output control, and transmission outputs are made high during the transmission of the control data and low during the transmission of the decoding data. Therefore, the range of the control data is extended, while the range of the decoding data is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a remote control device composed of a transmitter and a receiver, and more particularly to a remote control device effective for preventing unauthorized operation.

[0002]

2. Description of the Related Art Conventionally, many remote control devices have been used for remote control using radio waves or infrared rays.
For example, it is also used as a key substitute for lock control of automobile doors. In particular, in the case of such a usage method, in order to prevent malfunction by another remote control device, an identification code for identifying the remote control device is added to the transmission signal in the remote control device, and this identification code is Remote control devices that prevent remote control unless they match are in widespread use. However, even in such a remote control device, the remote control device may be abused by a person other than the authorized user by intercepting the transmission signal, storing it, and then transmitting the same signal.

For this reason, there has been proposed a code-variable type remote control device which sequentially transmits a control signal, an identification code and the like for each transmission. In this method, it is necessary to register the decoded data for decoding the control signal, the identification code, etc. on the transmitter side and the receiver side respectively. For example, when changing the identification code in a predetermined order, it is necessary to register the order of the identification code transmitted from the transmitter (registered in the transmitter) also in the receiver side.

As a method therefor, there is a method of mounting a memory (ROM) in which decoded data is written in advance in a receiver. Further, there is a method in which a write mode is provided in the transmitter and the receiver so that the decrypted data is sent from the transmitter, the decrypted data is received by the receiver side, and is registered in a memory (eg, EEPROM) on the receiver side.

[0005]

However, in the former method of mounting the memory, when the transmitter fails, is damaged, or is lost, the memory on the receiver must be replaced with a memory corresponding to the new transmitter. Therefore, the maintainability is poor, and in the case where the function that can be operated by a plurality of transmitters is added, the number of memories becomes large and problems in mounting (area, circuit pattern, connector, etc.) occur.

In the latter case, although the number of times of transmission is small, since unencrypted decrypted data is transmitted, interception of the decrypted data reduces the security of the remote control device. The present invention solves such a problem, and an object of the present invention is to provide a remote control device having high maintainability and crime prevention.

[0007]

In order to achieve the above object, the present invention provides a control signal transmitting section for transmitting control data for controlling the operation of a controlled device, and a control signal transmitting section for decoding the control signal. A transmitter having a decryption signal transmission unit for transmitting decryption data, and receiving and storing the signal decryption data from the transmitter, receiving the control data from the transmitter, and transmitting the control data based on the stored decryption data. In a remote control device consisting of a receiver that decodes control data and controls the operation of controlled equipment, the transmission output is made high when sending control data to the transmitter, and made low when sending decoded data. A transmission output control unit is provided.

[0008]

According to the present invention by the above means, the transmission output becomes high when the control data is sent to the receiver, and the transmission output becomes low when the decoded data is sent to the receiver. It becomes longer and the distance of decrypted data becomes shorter. Therefore, it is possible to reduce the possibility of intercepting decoded data without narrowing the controllable range of the controlled device.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention, showing a remote control device for controlling a door lock of an automobile. Reference numeral 1 denotes a transmitter of the remote control device, which operates the transmission switch 7 to transmit control data or decoded data stored in the memory 3 from the antenna 2.

A memory 3 includes data for identifying the transmitter 1 and data for operating the door lock device, and is necessary for decrypting the encrypted control data and the encrypted control data. The decrypted data and the program of the microcomputer 4 are stored. A microcomputer 4 controls peripheral devices according to the operated switches.

Reference numeral 5 is a transmission circuit, the operation of which is controlled by a control signal from the microcomputer 4, and the carrier wave is modulated by control data and decoding data input from the microcomputer 4 and transmitted from the antenna 2 as a radio wave. . Reference numeral 6 denotes a mode switch, and the microcomputer 4 changes the mode from the normal mode to the writing mode for a predetermined time after the mode switch 6 is operated.

Reference numeral 7 denotes a transmission switch, and when the transmission switch is operated, the microcomputer 4 outputs the data to be transmitted to the transmission circuit 5 according to the mode and the transmission circuit 5
Control the output level of. Specifically, if the transmission switch 7 is operated in the normal mode, encrypted control data for controlling the door lock is transmitted with high power, and if the transmission switch is operated in the writing mode, the encryption is encrypted. Decrypted data for decrypting the converted control data is transmitted with low power.

Next, 10 is a receiver of the remote control device, which receives the radio wave transmitted from the transmitter 1 and controls the controlled device 15. Reference numeral 11 is an antenna for receiving a radio wave from the transmitter 1. A reception circuit 12 demodulates and amplifies the radio wave from the transmitter 1 received by the antenna 11 and outputs the demodulated and amplified radio wave to the microcomputer 13.

Reference numeral 13 denotes a microcomputer, which controls a door lock device 15 which is a controlled device via an interface 14 according to an output signal from the receiving circuit 12. Specifically, the microcomputer 13 writes the decoded data in the memory 16 if the output signal from the receiving circuit 12 is the decoded data, and writes it in the memory 16 if the output signal from the receiving circuit 12 is the control data. The control data is decrypted using the written decryption data, it is determined whether the control data is legitimate, and if it is legitimate, the door lock device 1
5 control, for example, door lock open control is performed.

Reference numeral 16 denotes a memory, which stores the decoded data transmitted from the transmitter 1, the program of the microcomputer 13, and the like. The door lock device 15 controls the lock (lock) of the door of the automobile, and is a remote control device (receiver 1
The door lock is opened and closed according to the control signal from 0).
FIG. 2 is a diagram showing a communicable area of the remote control device.

Since the control data of the remote control device has a high transmission output, it is possible to communicate even when the transmitter 1 and the receiver 10 are relatively apart (within ab), and the communicable area is wide. On the other hand, because the transmitted output of decrypted data is low,
Transmitter 1 and receiver 10 are relatively close (within a-c)
Otherwise, communication is not possible and the communication area is small.
Therefore, the range in which the decrypted data can be intercepted is narrowed, and the security of the remote control device can be enhanced. Since the communicable range of the control data is not narrowed, the operability does not deteriorate as long as the regular transmitter 1 is used.

Next, the operation method will be described. When controlling the door lock device 15, the transmission switch 7 is operated within the controllable area. Then, the control data is transmitted from the transmitter 1 with a relatively high output, and the receiver 10 receives the control data to control the door lock device 15. When writing the decrypted data, the mode switch 6 is operated within the decrypted data communicable area (near the receiver b), and then the transmission switch 7 is operated within a predetermined time. Then, the decoded data is transmitted from the transmitter 1 at a low output, and then the receiver 1
The 0 receives the decrypted data and the decrypted data is written to the memory 16.

Next, the processing performed by the microcomputer 4 of the transmitter 1 will be described with reference to the flowchart of FIG. Microcomputer 4
Starts processing when power is supplied (when a battery is connected). In step S1, it is determined whether or not the transmission switch 7 is operated. If it is operated, the process proceeds to step S2, and if it is not operated, the determination in step S1 is repeated.

In step S2, it is determined whether or not the writing mode is set. If the writing mode is set, step S3 follows. If it is not writing mode, step S4 follows. The write mode is set only for a certain period of time (for example, 5 seconds) after the mode switch 6 is operated, and is canceled (returns to the normal mode) after the certain period of time elapses. It is realized by an interrupt process triggered by.

In step S3, the transmission circuit 5 is controlled so that the transmission output becomes a predetermined low output, and the decoded data for decoding the control data is output to the transmission circuit 5, and the decoded data is transmitted from the transmission circuit 5. Then, the process ends (return to step S1). In step S4, the control data is encrypted based on the decrypted data, and the process proceeds to step S5.
Then, in step S5, the transmission circuit 5 is controlled so that the transmission output is high, and the encrypted control data is output to the transmission circuit 5, and the control data is transmitted from the transmission circuit 5 to end the processing ( Return to step S1).

Next, the processing performed by the microcomputer 13 of the receiver 10 will be described with reference to the flowchart of FIG. The microcomputer 13 on the receiver side also starts processing when power is supplied (when a battery is connected). In step S11, it is determined whether or not the data is received. If the data is received, the process proceeds to step S12. If not, the step S11 is performed.
Is repeated.

This determination can be made based on whether or not any data is output from the receiving circuit 12. Step S1
In step 2, the data is decrypted and the process proceeds to step S13. In step S13, it is determined whether the decrypted data is data from the legitimate transmitter 1, and if it is data from the legitimate transmitter 1, the process proceeds to step S14, and if not, the process returns to step S11.

In step S14, it is determined whether or not the data is control data. If the data is control data, the process proceeds to step S15, a signal for controlling the door lock device 15 is output to the door lock device 15, and the process ends, and step S11 Return to. If it is determined in step S14 that the data is not control data, that is, if the data is decrypted data, the process proceeds to step S16, the decrypted data stored in the memory 16 is rewritten, and then the process ends and the process proceeds to step S11. Return.

Next, an example of the decrypted data and the control data will be described. For example, the transmitter 1 changes the control data each time the transmission switch 7 is operated once, and transmits the control data. Then, the change rule of the control data is stored in the memory 3 as the decrypted data, and the transmitter 1 changes the control data to be transmitted according to the decrypted data.

Then, the receiver 10 previously receives the decoded data from the transmitter 1 and stores it in the memory 16, and every time the control data from the legitimate transmitter 1 is received, the received control data is The comparison data is updated to determine whether the data is from the legitimate transmitter 1. For example, it is assumed that the decryption data is stored such that the control data is changed in the order of A, B, and C (in the case of a pair of regular transmitter 1 and receiver 10, the same decryption data is stored. ing). Then, when the transmission switch 7 is operated, the transmitter 1 transmits A as control data for the first time according to the decoded data, and transmits the control data to be transmitted next to B.
And set. If the received control data is A according to the decoded data, the receiver 10 processes it as the control data from the legitimate transmitter 1, and the control data to be judged next as the control data from the legitimate transmitter 1 is B. And set. Thereafter, this processing is continued, and the control data transmitted by the transmitter 1 side and the control data determined by the receiver 10 side as the regular control data change in synchronization.

The deciphered data includes the deciphering data and the identification code having a relatively large number of digits which is set in common to the transmitter 1 and the receiver 10 forming a legitimate pair, and is received. The machine 10 rewrites the decrypted data written in the memory 16 when the identification code included in the decrypted data matches its own identification code. The encryption method is not limited to the above method, and various methods can be used.

As described in detail above, according to the remote control device of this embodiment, the control data is transmitted at a high output, and the decoded data for decoding the control data is transmitted at a low output. , The possibility of intercepting decrypted data is low, and the security of the remote control device is high. or,
Since the control data is transmitted with high output, the controllable area does not become narrow, and the operability and crime prevention of the remote control device can both be achieved.

[0028]

As described above, according to the present invention, when the control data is sent to the receiver, the transmission output becomes high, and when the decoded data is sent to the receiver, the transmission output becomes low. It becomes longer and the distance of decrypted data becomes shorter. Therefore, the possibility of intercepting decrypted data can be reduced without narrowing the controllable range of the controlled device, and the maintainability is high and the crime prevention is high.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention.

FIG. 2 is a diagram showing a communicable area of a transmitter.

FIG. 3 is a flowchart showing a microcomputer operation of a transmitter.

FIG. 4 is a flowchart showing a microcomputer operation of a receiver.

[Explanation of symbols]

 1 ・ ・ Transmitter 2 ・ ・ ・ ・ ・ ・ Antenna 3 ・ ・ ・ ・ ・ ・ ・ ・ Memory 4 ・ ・ ・ ・ ・ ・ Microcomputer

Claims (1)

[Claims] 1. A transmitter having a control signal transmitting section for transmitting control data for controlling the operation of a controlled device, and a decoding signal transmitting section for transmitting decoding data for decoding the control signal, A receiver for receiving and storing signal decoding data from the transmitter, receiving the control data from the transmitter, decoding the control data based on the stored decoding data, and controlling the operation of the controlled device. The remote control device according to claim 1, wherein the transmitter is provided with a transmission output control unit for increasing the transmission output when transmitting the control data and decreasing the transmission output when transmitting the decoded data.