JP2022178454A - Communication system and communication method - Google Patents

Abstract

To provide a communication system and a communication method that can reduce communication time.SOLUTION: A communication system 18 is used on an authentication system 3 that authenticates a terminal 1 by causing the terminal 1 to communicate with an operation target 2 and activates the operation target 2. When transmitting transmission data Sk from one of the terminal 1 and the operation target 2 to the other, a transmission processing unit 19 superimposes ranging signals St with the amplitude of the signals set to a specified value on at least a part of the transmission data Sk, and transmits the transmission data Sk. When the other one of the terminal 1 and the operation target 2 receives the transmission data Sk, a determination unit 20 determines whether the communication is correct based on the ranging signals St superimposed on the transmission data Sk.SELECTED DRAWING: Figure 1

Description

The present invention relates to a communication system and communication method for communicating between a terminal and an operation target.

Conventionally, an electronic key system that activates a vehicle by authenticating an electronic key through wireless communication is well known. By the way, in this type of electronic key system, for example, a terminal located far away from the vehicle is connected to the vehicle via a repeater for communication, and authentication is fraudulently established. In order to prevent this fraudulent act, for example, Japanese Patent Laid-Open No. 2002-200002 discloses a technique for determining whether communication is legitimate or fraudulent by transmitting and confirming a distance measurement signal during communication.

JP 2013-130031 A

However, in the case of the method of individually transmitting the distance measurement signals during communication, communication time is required for the communication of the distance measurement signals. Therefore, there was a concern that the communication time would become long.

A communication system for solving the above-mentioned problems is a configuration used for an authentication function that causes a terminal to communicate with an operation target to authenticate the terminal and activates the operation target, and a transmission processing unit that, when transmitting transmission data, superimposes a ranging signal having a signal amplitude set to a specified value on at least a part of the transmission data, and transmits the transmission data; a determination unit that determines whether communication is correct based on the ranging signal superimposed on the transmission data when the transmission data is received by the other of the objects.

A communication method for solving the above-mentioned problems is a method used for an authentication function that causes a terminal to communicate with an operation target to authenticate the terminal, and activates the operation target. when transmitting the transmission data, superimposing a ranging signal whose signal amplitude is set to a specified value on at least a part of the transmission data, and transmitting the transmission data; On the other hand, when the transmission data is received, the communication system for managing the communication between the terminal and the operation object determines whether the communication is correct based on the ranging signal superimposed on the transmission data. Let

According to the present invention, communication time can be reduced.

1 is a configuration diagram of a communication system according to one embodiment; FIG. 4A and 4B are data structure diagrams representing a binary code of transmission data; FIG. FIG. 4 is a data structure diagram showing a specific example of superimposition of ranging signals. Schematic diagram of communication performed between a terminal and a verification device. FIG. 4 is a data structure diagram showing a specific example of transmission data on which a ranging signal is superimposed; Schematic diagram showing an example of unauthorized communication. Explanatory drawing which shows the specific example of edge detection.

An embodiment of a communication system and communication method is described below.
As shown in FIG. 1, the operation target 2 of the terminal 1 has an authentication system 3 as an authentication function for authenticating the terminal 1 by wireless communication. The terminal 1 is preferably, for example, an electronic key 4 mainly having key functions. The operation target 2 is preferably a vehicle 5, for example. The authentication system 3 includes a smart system that authenticates the terminal 1 upon communication from the terminal 1 and controls the operation target 2 . A smart system is, for example, a system that authenticates the terminal 1 by automatically executing smart communication between the terminal 1 and the operation target 2 without imposing a user operation.

The authentication system 3 includes a verification device 7 that verifies the terminal 1 . The verification device 7 stores the ID information Did of the terminal 1 in a memory (not shown). The ID information Did includes, for example, a unique ID code possessed by each terminal 1, an authentication key used for encrypted communication, and the like. The verification device 7 is provided with a transmitter 8 that transmits radio waves to the terminal 1 and a receiver 9 that receives radio waves from the terminal 1 . The transmitter 8 transmits radio waves in the LF (Low Frequency) band, for example. The receiver 9 receives, for example, UHF (Ultra High Frequency) band radio waves.

The terminal 1 includes a terminal controller 11 that controls the operation of the terminal 1, a receiver 12 that receives radio waves, and a transmitter 13 that transmits radio waves. The terminal control unit 11 stores ID information Did assigned to each terminal 1 in a memory (not shown). The receiving unit 12 receives, for example, radio waves in the LF band. The transmitter 13 transmits, for example, radio waves in the UHF band.

A device 15 is connected to the collation device 7 via a communication line 14 . The communication line 14 is preferably CAN (Controller Area Network) or LIN (Local Interconnect Network), for example. The device 15 is, for example, a door lock device that controls locking/unlocking of doors, a steering lock device that switches whether the steering wheel can be operated or not, and an engine control device that controls the engine. The verification device 7 verifies the ID information Did of the terminal 1 by two-way communication of LF-UHF, and controls the device 15 based on the verification result.

The authentication system 3 has a communication function (communication system 18) that prevents unauthorized communication by determining whether the communication between the terminal 1 and the operation target 2 is correct. In this example, when transmission data Sk is transmitted in communication for authentication, the communication system 18 also transmits a ranging signal St for confirming the actual distance between the terminal 1 and the operation target 2. It has a distance measurement determination function that manages whether the communication is correct or not based on the distance measurement signal St. Further, the distance measurement determination function of this example is a function of executing communication determination by superimposing the distance measurement signal St on at least a part of the transmission data Sk and transmitting it to the other party. The ranging signal St is also data that can determine the validity of the transmission data Sk.

The communication system 18 includes a transmission processing unit 19 that superimposes the ranging signal St on the transmission data Sk communicated between the terminal 1 and the operation target 2 and transmits the transmission data Sk. In the case of this example, the transmission processing unit 19 is provided in the operation target 2 (verification device 7). For example, when the transmission data Sk is transmitted from the operation target 2 to the terminal 1, the transmission processing unit 19 superimposes the ranging signal St whose signal amplitude is set to a specified value on at least a part of the transmission data Sk. , to transmit the transmission data Sk.

In the case of data transmitted from the collation device 7, the transmission data Sk includes, for example, a wake signal for activating the terminal 1. FIG. The transmission data Sk also includes a challenge code used for authentication when performing challenge-response authentication between the terminal 1 and the verification device 7 .

As shown in FIGS. 2(a) and 2(b), the transmission data Sk is expressed as a binary code by combining Hi and Lo signals. As an example, as shown in FIG. 2(a), for example, the case where a Hi signal exists within one period is defined as one of bits "1" and "0", and the case where only a Lo signal exists within one period. A format in which the other of bits "1" and "0" is used. As another example, as shown in FIG. 2B, for example, when signals are arranged in the order of Hi signal and Lo signal in one cycle, one of bits "1" and "0" is set. , the arrangement order of the Lo signal and the Hi signal is the other of "1" and "0".

As shown in FIG. 3, the transmission processing unit 19 superimposes the ranging signal St on the transmission data Sk by defining the bit string of the transmission data Sk by amplitude level values and time intervals. In this example, the transmission processing unit 19 generates transmission data Sk superimposed with the ranging signal St by expressing a binary code in the signal of period T by combining the high-level signal Dh and the low-level signal Dl. do. Also, the ranging signal St is preferably superimposed on a portion of the transmission data Sk.

Specifically, as shown in the upper part of FIG. 3, bit "0" is a bit combination in which a high level signal Dh with a period T is switched to a low level signal Dl with a period T, or a low level signal Dl with a period T. is represented by a bit combination that changes to a high-level signal Dh with a period T. Further, as shown in the lower part of FIG. 3, bit "1" is represented by a bit combination of two high-level signals Dh of cycle T, or a bit combination of two low-level signals Dl of cycle T. there is

As shown in FIG. 1, the communication system 18 includes a determination unit 20 that determines whether or not the communication is fraudulent communication based on the ranging signal St included in the transmission data Sk. When the transmission data Sk is received by the other of the terminal 1 and the operation target 2, the determination unit 20 determines whether the communication is correct based on the ranging signal St superimposed on the transmission data Sk. In this example, the determination unit 20 is provided in the terminal 1 (terminal control unit 11). Thus, the determination of the ranging signal St is performed at the terminal 1 .

The determination unit 20 determines whether the communication is correct or not by checking the values of the high-level signal Dh and the low-level signal Dl representing the ranging signal St. If the determination unit 20 can confirm that the high-level signal Dh and the low-level signal Dl of the ranging signal St take prescribed values, the determination unit 20 determines that the communication currently being performed is normal communication, and permits the communication. On the other hand, when confirming that at least one of the high-level signal Dh and the low-level signal Dl of the ranging signal St does not take a prescribed value, the determination unit 20 determines that the communication currently being executed is unauthorized communication, is disabled and the communication is forcibly terminated.

Next, the operation of the communication system 18 and the transmission method of this embodiment will be described.
As shown in FIG. 4, the verification device 7 starts smart communication with the terminal 1 when the terminal 1 enters a communication area formed by LF band radio waves (for example, wake signals). In this example, the verification device 7 transmits transmission data Sk for authentication to the terminal 1 . The transmission data Sk includes, for example, a preamble used for signal synchronization and transmission information Sk1 following the preamble. The transmission information Sk1 includes, for example, a command for notifying what kind of signal the transmission data Sk is, a challenge code used in challenge-response authentication, and the like.

At this time, as shown in FIG. 5, the transmission processing unit 19 superimposes the distance measurement signal St on the transmission information Sk1 and causes the collation device 7 to transmit the transmission data Sk. The ranging signal St may be superimposed on any data string in the transmission information Sk1, for example. In the case of the example of FIG. 5, the location where the ranging signal St is superimposed on the transmission data Sk is such that the bit "1" is "high level, low level", the next bit "0" is "low level, high level", the next bit "0" is "low level, high level", the next bit "1" is "low level, low level", the next bit "0" is "high level, low level", the next is represented by a signal level combination of "high level, high level".

Upon receiving the transmission data Sk transmitted from the verification device 7, the terminal 1 reads the transmission data Sk. Specifically, the terminal control unit 11 reads "0" and "1" of the transmission data Sk and acquires the data content of the transmission data Sk. In particular, in the case of this example, the location where the ranging signal St is included in the transmission data Sk is the relative level value of the signal separated by the period T, that is, the combination of the high-level signal Dh and the low-level signal Dl. Decode the data Sk.

Specifically, when the signal group for two cycles of the signal with the cycle T is a combination of the high level signal Dh and the high level signal Dh, or when the signal group for two cycles of the cycle T is a combination of the low level signal Dl and the low level signal Dh. In the case of a combination of signals Dl, this is read as bit "1". Further, when the signal group for two cycles of the cycle T is a combination of the high level signal Dh and the low level signal Dl, or the signal group for two cycles of the cycle T is a combination of the low level signal Dl and the high level signal Dh. read as bit '0'. As described above, "0" and "1" of the transmission data Sk are read.

The terminal 1 reads the transmission data Sk and determines whether the communication is correct or not based on the ranging signal St superimposed on the transmission data Sk. In this example, the determination unit 20 determines whether the communication is legitimate communication or unauthorized communication by checking the level value (absolute level value) of the ranging signal St. Specifically, by confirming whether the level values of the high-level signal Dh and the low-level signal Dl representing the distance measurement signal St take prescribed values, it is possible to determine whether the communication is legitimate communication or unauthorized communication. determine whether

If the determination unit 20 can confirm that the level values of the high-level signal Dh and the low-level signal Dl of the ranging signal St both take the specified values, it determines that the communication is regular communication. Thereby, subsequent communication is continued. When the communication is normal communication, the terminal 1 transmits response data Sr (see FIG. 4) as a response to the transmission data Sk. The response data Sr includes, for example, ID information Did of the terminal 1 and a response code used in challenge-response authentication.

Upon receiving the response data Sr transmitted from the terminal 1, the verification device 7 authenticates the response data Sr. Authentication of the response data Sr includes, for example, collation of the ID information Did and confirmation of the response code. The verification device 7 permits the operation of the operation target 2 when the response data Sr is authenticated. At this time, when the operation target 2 is the vehicle 5, the locking/unlocking of the vehicle door is permitted or executed, or the engine starting is permitted. Therefore, an authorized user can get into the vehicle 5 and start the engine.

On the other hand, when confirming that at least one of the high-level signal Dh and the low-level signal Dl of the ranging signal St does not reach the specified value, the determination unit 20 determines that the communication is unauthorized communication. As a result, subsequent communication is disabled. Therefore, the terminal 1 forcibly terminates the communication or transmits the response data Sr indicating that the judgment is not established to the collation device 7, thereby preventing the subsequent communication from being executed.

Here, FIG. 6 shows an example of unauthorized communication using the repeater 23. As shown in FIG. As shown in the figure, for example, when a terminal 1 exists at a position far away from a vehicle 5 which is an operation target 2, a repeater 23 is interposed between the terminal 1 and the vehicle 5 to establish communication. The act of establishing illegally is regarded as a problem. In this case, the authentication of the terminal 1 is fraudulently established by a third party without the involvement of the user. Therefore, some countermeasures have been required to prevent damage such as vehicle theft.

By the way, when the radio wave is relayed by the repeater 23, there is a current situation in which the signal cannot be completely reproduced and transferred. Therefore, when the distance measurement determination function of this example is used, the transmission data Sk cannot be reproduced up to the intensity and transferred, so that the communication is determined to be unauthorized communication when the distance measurement signal St is confirmed. Therefore, since it is possible to detect unauthorized communication using the repeater 23 and prevent the communication from being established unauthorized, it is possible to improve security against unauthorized use.

In this example, the ranging signal St is superimposed on the transmission data Sk. Therefore, the transmission time can be shortened compared to the case where the ranging signal St is transmitted separately for the transmission data Sk. Therefore, it is also possible to shorten the time required for authentication communication.

Further, as shown in FIG. 7, the determination unit 20 may determine whether or not the communication is fraudulent by checking signal edges in the transmission data Sk on which the ranging signal St is superimposed. In this example, an edge occurs in the waveform when switching from the high level signal Dh to the low level signal Dl and when switching from the low level signal Dl to the high level signal Dh. Therefore, the determination unit 20 determines that the communication is legitimate communication when there is a signal edge at the location where the ranging signal St is superimposed on the transmission data Sk, and determines that the communication is unauthorized communication when there is no signal edge. I judge.

According to the communication system 18 and the communication method of the above embodiment, the following effects can be obtained.
(1) The authentication function (authentication system 3 ) is a function that allows the terminal 1 to communicate with the operation target 2 to authenticate the terminal 1 and activate the operation target 2 . The communication system 18 of this example is used for this authentication function. When transmission data Sk is transmitted from one of the terminal 1 and the operation target 2 to the other, the transmission processing unit 19 of the communication system 18 includes, in at least a part of the transmission data Sk, distance measurement data in which the amplitude of the signal is set to a specified value. The signal St is superimposed to transmit the transmission data Sk. When the transmission data Sk is received by the other of the terminal 1 and the operation target 2, the determination unit 20 of the communication system 18 determines whether the communication is correct based on the ranging signal St superimposed on the transmission data Sk.

According to the configuration of this example, when the transmission data Sk includes the ranging signal St to determine whether the communication is legitimate communication or unauthorized communication, the ranging signal St is superimposed on the transmission data Sk. It becomes unnecessary to transmit the ranging signal St individually for the data Sk. Therefore, communication time can be shortened.

(2) A location where the ranging signal St is superimposed on the transmission data Sk is represented by each binary code by a combination of the high level signal Dh and the low level signal Dl. According to this configuration, it is determined whether the communication is legitimate communication or unauthorized communication based on a plurality of types of signals having different level values, which contributes to an improvement in determination accuracy.

(3) The determination unit 20 determines whether the communication is correct or not by checking the values of the high level signal Dh and the low level signal Dl. According to this configuration, both the values of the high-level signal Dh and the low-level signal Dl are checked to determine whether the communication is legitimate communication or unauthorized communication. can be done.

(4) In the transmission data Sk, a binary code is represented by a combination of Hi signal and Lo signal at locations where the ranging signal St is not superimposed. According to this configuration, it is possible to appropriately set the data string of the transmission data Sk using a combination of the Hi signal and the Lo signal.

(5) The transmission data Sk includes a preamble used for signal synchronization and transmission information Sk1 following the preamble. The transmission processing unit 19 superimposes the ranging signal St on at least part of the transmission information Sk1. According to this configuration, the distance measurement signal St can be superimposed on the optimum data string in the transmission data Sk.

In addition, this embodiment can be changed and implemented as follows. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.
• Bit "1" may be used only in combination with, for example, two high level signals Dh. Similarly, bit '1' may only be used in combination with two low level signals Dl, for example.

- Bit "0" may be used only for signal combinations in which, for example, the high-level signal Dh and the low-level signal Dl are arranged in order. Similarly, bit '0' may only be used for signal combinations that are in sequence, for example, a low level signal Dl and a high level signal Dh.

- Bit "0" can be a set of two high level signals Dh or a set of two low level signals Dl. Bit "1" may be a combined signal of high level signal Dh and low level signal Dl.

- The transmission data Sk may be transmitted at any timing as long as it is data communicated between the terminal 1 and the operation target 2 .
- The transmission data Sk may be data transmitted from the terminal 1 .

- It is preferable that "2T", which is a value for two periods T, is one period of the transmission data Sk.
- The location where the ranging signal St is superimposed may be any location within the transmission data Sk.

- The location where the ranging signal St is superimposed may be changed for each transmission within the transmission data Sk.
- The authentication system 3 is not limited to a smart system.

- For communication between the terminal 1 and the operation target 2, various types of communication such as short-range wireless communication can be used. Examples of short-range wireless communication include Bluetooth (registered trademark), Wi-Fi (registered trademark), and UWB (Ultra Wide Band).

- The operation target 2 is not limited to the vehicle 5, and may be changed to another member.
- The communication system 18 is not limited to being used in the vehicle 5, and may be used in other systems and devices.

Each of the transmission processing unit 19 and the determination unit 20 may be configured by [1] one or more processors that operate according to a computer program (software), [2] such a processor and various processes It may be configured in combination with one or more dedicated hardware circuits such as an application specific integrated circuit (ASIC) that performs at least part of the processing. A processor includes a CPU and memory, such as RAM and ROM, which stores program code or instructions configured to cause the CPU to perform processes. Memory (computer-readable media) includes any available media that can be accessed by a general purpose or special purpose computer. Alternatively, instead of a computer including the above processor, a processing circuit configured by one or more dedicated hardware circuits that perform all of the various types of processing may be used.

- Each of the transmission processing unit 19 and the determination unit 20 may be configured by an independent processor, or may be configured by a processor with a shared function. Thus, the transmission processing unit 19 and the determination unit 20 are not limited to independent functional blocks, and may be configured from one functional block, or may be configured from a partially shared functional block.

- Although the present disclosure has been described with reference to examples, it is understood that the present disclosure is not limited to such examples or structures. The present disclosure also includes various modifications and modifications within the equivalent range. In addition, various combinations and configurations, as well as other combinations and configurations, including single elements, more, or less, are within the scope and spirit of this disclosure.

1 terminal 2 operation target 3 authentication system 18 communication system 19 transmission processing unit 20 determination unit Sk transmission data Sk1 transmission information St distance measurement signal Dh high level signal, Dl--Low level signal.

Claims (6)

A communication system used for an authentication function that causes a terminal to communicate with an operation target, authenticates the terminal, and activates the operation target,
When transmission data is transmitted from one of the terminal and the operation target to the other, the transmission data is transmitted by superimposing a ranging signal having a signal amplitude set to a specified value on at least a part of the transmission data. a transmission processing unit that causes
and a determination unit that determines whether communication is correct based on the ranging signal superimposed on the transmission data when the transmission data is received by the other of the terminal and the operation target. 2. The communication system according to claim 1, wherein each binary code is expressed by a combination of a high-level signal and a low-level signal at a location where the ranging signal is superimposed on the transmission data. 3. The communication system according to claim 2, wherein the determination unit determines whether the communication is correct or not by checking the values of the high level signal and the low level signal. 4. The transmission data according to any one of claims 1 to 3, wherein a binary code is expressed by a combination of a Hi signal and a Lo signal at a location where the distance measurement signal is not superimposed. Communications system. The transmission data includes a preamble used for signal synchronization and transmission information following the preamble,
The communication system according to any one of claims 1 to 4, wherein the transmission processing section superimposes the ranging signal on at least part of the transmission information. A communication method used for an authentication function that causes a terminal to communicate with an operation target to authenticate the terminal and activate the operation target,
When transmission data is transmitted from one of the terminal and the operation target to the other, the transmission data is transmitted by superimposing a ranging signal having a signal amplitude set to a specified value on at least a part of the transmission data. and
communication between the terminal and the operation target, wherein when the other of the terminal and the operation target receives the transmission data, the communication between the terminal and the operation target is determined based on the ranging signal superimposed on the transmission data. A communication method that is executed by a communication system that manages

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