JP5139962B2 - Power transmission wireless communication system - Google Patents

Description

  The present invention relates to a power transmission type wireless communication system in which a communication terminal is activated by a driving radio wave transmitted from a communication master to perform wireless communication.

In recent years, wireless communication is used for communication of various information between devices in many devices. For example, a technique using a communication standard of RFID (Radio Frequency IDentification) (see, for example, Patent Document 1) is widely used as a kind of this type of wireless communication system. RFID communication is a type of short-range wireless communication that uses a small IC tag (Integrated Circuit tag) that records various types of information. Because the tag is small in size, it tends to be widely used in various devices and devices. is there. In addition, there is a passive type in which an IC tag is activated by a driving radio wave received from a communication partner. In this case, there is no need to place a battery (power supply) on the IC tag, so it is mounted on a small device that cannot be increased in size. There are many opportunities.
JP 2006-311415 A

  By the way, in recent years, various types of wireless communication are used for exchanging various types of information in many devices and apparatuses, and therefore there are various radio waves (floating radio waves) flying in the space. Therefore, some of these stray radio waves have a frequency band that adversely affects RFID communication.When radio waves in this band are generated under the execution of RFID communication, this affects the device as noise, for example, There is no denying the possibility that RFID communication will not be established due to the cancellation of regular radio waves due to noise. In this case, re-execution of RFID communication is imposed on the user, which leads to a problem that makes the user feel stressed.

  An object of the present invention is to provide a power transmission wireless communication system capable of improving the noise resistance of the wireless communication on the configuration that can start the communication terminal with the driving radio wave transmitted from the communication master. .

In order to solve the above problem, in the present invention, when the communication master performs wireless communication with the communication terminal, the transmission data that conveys the contents of the data is transmitted together with the driving radio wave that is the power of the communication terminal. Thus, in the power transmission type wireless communication system that performs the wireless communication by causing the communication terminal to operate based on the transmission data while operating the communication terminal with the driving radio wave, noise in the communication environment of the wireless communication Noise monitoring means for monitoring the presence or absence of noise in the communication master, and a master-side transmission channel that switches data transmission of the transmission data to another channel that is not affected by the noise when the noise monitoring means determines that there is noise and a switching means, the master-side outgoing channel switching means, when said noise monitoring means determines that there is noise The transmission data is transmitted from a signal transmission unit capable of transmitting a wireless signal of a channel that is not affected by the noise, and the driving radio wave is transmitted from a signal transmission unit that transmits a wireless signal of the channel affected by the noise. The gist is to keep it as it is.

  According to this configuration, when the communication master performs wireless communication with the communication terminal, the communication master generates drive radio waves used as power of the communication terminal and transmission data as data contents that the communication master wants to transmit to the communication terminal. Called. When the communication terminal receives the drive radio wave transmitted from the communication master, the communication terminal starts up using the drive radio wave as power. Then, the activated communication terminal receives the transmission data transmitted from the communication master following this driving radio wave, and operates based on this data. Therefore, if the wireless communication system is a power transmission type in this way, it is not necessary to mount a power source such as a battery in the communication terminal, so that it is possible to reduce the size and cost of the communication terminal accordingly. Become.

In addition, in a communication environment where the communication master performs wireless communication with the communication terminal, whether or not noise that may affect this communication is generated is monitored by the noise monitoring means. When the noise monitoring means detects that noise is generated in this communication environment, the outgoing data transmission channel is switched to a channel that is not affected by the noise, and the outgoing data is transmitted from the communication master through this channel. Called. Therefore, if the wireless communication system is a multi-channel system that switches the transmission channel according to the presence or absence of noise in this way, even if noise occurs in the communication environment of wireless communication, communication of outgoing data transmitted from the communication master is performed. It can be transmitted to the terminal. As described above, it is possible to reduce the size of the communication terminal and improve the noise resistance of the wireless communication.
According to this configuration, when noise is generated in the communication environment, the communication terminal starts up using this noise as power, but even if this noise occurs intermittently, The power supply is filled with driving radio waves. For this reason, since it becomes possible to always provide electric power to the communication terminal, it is possible to support stable power supply to the communication terminal. At this time, since the transmission of the transmission data is not affected by the transmission of the driving radio wave, the transmission data can be transmitted immediately, for example, and the transmission time of the transmission data can be shortened. .

  In the present invention, the communication terminal is provided with terminal-side transmission channel switching means for setting a transmission channel of reply data transmitted by the communication terminal in response to the transmission data as a transmission channel of the transmission data. This is the gist.

  According to this configuration, when the communication terminal transmits the reply data to the communication master in response to the transmission data received from the communication master, the reply data is transmitted on the same channel as the transmission data received from the communication master. By the way, the fact that the communication terminal has been able to receive the transmission data transmitted from the communication master can be considered that noise that affects the channel of the transmission data has not occurred in the communication environment of wireless communication. Therefore, if reply data transmitted from the communication terminal to the communication master is sent back through the channel at the time of data reception, the reply data can be transmitted to the communication master more reliably.

  In the present invention, an electronic key that transmits a unique key code by wireless communication is used as the communication terminal, and when the communication master receives the key code transmitted from the electronic key, The gist of the present invention is that the present invention is applied to an electronic key system that performs key collation in comparison.

  According to this configuration, since the power transmission type wireless communication system of this configuration is applied to the electronic key system, it is possible to provide an electronic key system with a small electronic key and high noise resistance.

  According to the present invention, the noise resistance of the wireless communication can be improved on the configuration in which the communication terminal can be activated by the driving radio wave transmitted from the communication master.

Hereinafter, an embodiment of an electric power transmission type electronic key system embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, the vehicle 1 includes an electronic key system 3 that performs key verification using a key code with an electronic key 2 that is used as a vehicle key, and a vehicle door (including a seat door and a luggage door). A door lock system 4 that locks and unlocks the door lock, and an engine system 5 that manages the power state (power position) and engine start / stop of the vehicle 1 are provided. The electronic key 2 is capable of narrow-range wireless communication with the vehicle 1, and transmits an ID code inherent to the electronic key 2 to the vehicle 1 by wireless communication to cause the vehicle 1 to perform key verification. A key that can be used. The vehicle 1 corresponds to a communication master, the electronic key 2 corresponds to a communication terminal, and the electronic key system 3 corresponds to a power transmission wireless communication system.

  The electronic key system 3 includes a key operation free system 6 that does not require individual key operations when the electronic key 2 transmits an ID code. The key operation free system 6 includes a smart entry system as a function that does not require a key operation at the time of door lock locking / unlocking operation. In this smart entry system, the vehicle 1 is provided with a verification ECU (Electronic Control Unit) 7 that performs key verification (ID verification) with the electronic key 2. The verification ECU 7 includes, for example, an external transmitter 8 installed in a vehicle door or the like to transmit an RF band (Radio Frequency: about 312 MHz) signal to the outside of the vehicle, an interior floor or the like to transmit the same RF band signal to the interior of the vehicle Is connected to an in-vehicle transmitter 9 and a tuner 10 capable of receiving an RF band signal. The verification ECU 7 is connected to the door lock system 4 and the engine system 5 via an in-vehicle LAN (Local Area Network) 11 that is one network in the vehicle.

  Further, the electronic key 2 is provided with a communication control unit (control IC: Integrated Circuit) 12 that performs overall control of various operations of the electronic key 2. The communication control unit 12 includes various devices such as a CPU (Central Processing Unit) 13 and a memory 14, and an ID code is registered in the memory 14 as a unique key code of the electronic key 2. The communication control unit 12 is connected to a key receiver 15 capable of receiving an RF band radio signal and a key transmitter 16 capable of transmitting an RF band radio signal. The communication control unit 12 sequentially monitors which type of radio signal is received by the key receiver 15 and manages the operation of signal transmission from the key transmitter 16.

  When the vehicle 1 is in a parked state, the verification ECU 7 intermittently transmits an RF band request signal Srq from the vehicle transmitter 8 to form a vehicle communication area for the request signal Srq around the vehicle, thereby narrow-band wireless communication ( Hereinafter, the establishment of smart communication) is attempted. When the electronic key 2 enters the outside communication area and receives the request signal Srq, the electronic key 2 responds to the request signal Srq and sends the ID signal Sid carrying the ID code registered in its own memory 14 to the RF band. Reply with the signal. When the tuner 10 receives the ID signal Sid and the smart communication is established, the verification ECU 7 compares the ID code registered in its own memory 17 with the ID code of the electronic key 2, so-called smart verification (outside the vehicle). Verification). The verification ECU 7 permits or executes the door lock locking / unlocking operation by the door lock system 4 when confirming that this external verification is established. The ID signal Sid corresponds to reply data.

  In addition, the key operation free system 6 has a function that can start and stop an engine (not shown) by a simple switch operation without requiring an actual vehicle key operation at the time of engine start and stop operation. There is a push engine start system. In this one-push engine start system, for example, when the driver enters the vehicle by a courtesy switch (not shown), the verification ECU 7 does not start from the previous external transmitter 8 but this time from the internal transmitter 9. A request signal Srq is transmitted to form an in-vehicle communication area throughout the vehicle. When the tuner 10 receives the ID signal Sid returned by the electronic key 2 entering the in-vehicle communication area, the verification ECU 7 compares the ID code registered in the electronic key 2 with the ID code of the electronic key 2, So-called smart verification (in-vehicle verification) is performed. When the verification ECU 7 confirms that the in-vehicle verification has been established, the verification ECU 7 permits the engine system 5 to switch the power supply state.

  As a result, when the push momentary engine switch (not shown) is pushed while the brake pedal is depressed while the engine is in the stopped state, the engine that has been in the stopped state is switched to the activated state. When the engine is in a movable state, if the engine switch is pushed while the range position of the select lever is in the parking position (P range), the engine is now switched to a stopped state. Furthermore, when the engine is stopped and the brake pedal is not depressed and only the engine switch is pushed, the power state is repeatedly switched in the order of power off → ACC on → IG on each time this push operation is performed.

  In addition, the electronic key system 3 of this example operates the electronic key 2 without a battery by transmitting a driving radio wave Svv from the vehicle 1 to the electronic key 2 and performing power transmission during wireless communication for key verification. The communication format conforming to the wireless power transmission system to be used is adopted. In this case, the external transmitter 8 (in-vehicle transmitter 9) is provided with a power transmission processing unit 18 that adds a power radio wave to the request signal Srq and transmits the request signal Srq. When transmitting the request signal Srq to the electronic key 2, the power transmission processing unit 18 first transmits the driving radio wave Svv as a power radio wave that can activate the electronic key 2 that does not have a battery. A request code Src which is the main data of the signal Srq is transmitted. For example, RFID is adopted as the communication standard for power transmission. The request code Src corresponds to outgoing data.

  When the key receiver 15 receives the drive radio wave Svv transmitted from the vehicle 1, it outputs this to the communication control unit 12. When the communication control unit 12 receives a voltage (startup voltage) based on the drive radio wave Svv from the key receiver 15, the operation state is switched from the standby state until then to the start-up state, and subsequently transmitted after the drive radio wave Svv. The incoming request code Src is accepted. The communication control unit 12 operates in accordance with the request code Src so as to transmit the ID signal Sid from the key transmitter 16 to the vehicle 1 as an operation in response to the request.

  Furthermore, as shown in FIGS. 2 to 5, the electronic key system 3 sets the communication frequency to a frequency (channel) that is not affected by noise even if noise occurs in the communication environment for key verification. A communication format conforming to a multi-channel system corresponding to noise by switching is adopted. The multi-channel of this example uses the frequency of channel 1 (hereinafter referred to as CH1) as the frequency (channel) that is normally used, and the frequency used when CH1 noise occurs in the communication environment of the electronic key system 3 Is switched to channel 2 (hereinafter referred to as CH2).

  As shown in FIGS. 2 and 3, the tuner 10 is provided with a noise monitoring unit 19 that monitors the presence or absence of noise that affects the request signal Srq. The noise monitoring unit 19 of this example monitors the presence or absence of noise that affects CH1, which is the normal transmission frequency of the request signal Srq. By the way, as shown in FIG. 4 and FIG. 5, for example, the tuner 10 prepares for reception to search which frequency radio signal exists in the communication environment as the first reception operation executed when receiving the radio signal. The operation is repeatedly executed at a predetermined polling cycle. This polling cycle is set to several hundred ms, for example. When the electronic key system 3 is a multi-channel system, this type of tuner 10 performs a CH1 reception preparation operation for searching for the presence / absence of reception of the CH1 radio signal and the reception of the CH2 radio signal as the reception preparation operation described above. The CH2 reception preparation operation for searching for presence / absence is continuously executed. When the tuner 10 receives the CH1 radio signal during the CH1 reception preparation operation, the tuner 10 enters an operation for capturing the CH1 radio signal. On the other hand, when the tuner 10 receives the CH2 radio signal during the CH2 reception preparation operation, The operation for capturing a radio signal is started. The noise monitoring unit 19 corresponds to noise monitoring means.

  When the noise monitoring unit 19 receives the CH1 radio signal during the CH1 reception preparation operation, the noise monitoring unit 19 cannot accept the CH1 radio signal normally and the reception time is up, or the received signal format is different. When it is confirmed, it is determined that the noise of the pair CH1 is generated in the communication environment. The noise monitoring unit 19 sequentially executes the noise monitoring and outputs the noise monitoring result to the verification ECU 7. Although the tuner 10 shares one receiving antenna, it has two receiving circuits, that is, a receiving circuit for CH1 and a receiving circuit for CH2, and one of these circuits selectively operates, so that CH1 and CH2 One radio signal can be received.

  As shown in FIGS. 2 and 3, the verification ECU 7 sets the transmission frequency of the request signal Srq (request code Src) to a channel that is not affected by noise based on the monitoring result of the noise monitoring unit 19. A transmission frequency setting unit 20 is provided. The vehicle-side transmission frequency setting unit 20 of this example performs signal transmission on the channel on the side that does not receive noise among CH1 and CH2. For example, when the vehicle-side transmission frequency setting unit 20 obtains a noise-free notification from the noise monitoring unit 19, for example, the vehicle-side transmission frequency setting unit 20 performs communication at the frequency of the channel CH1 without changing the transmission frequency of the request signal Srq. Further, when the vehicle-side transmission frequency setting unit 20 obtains a notification of noise from the noise monitoring unit 19, the transmission frequency of the request signal Srq is switched to CH2 that is not affected by noise (CH1 in this example), and communication is performed. Let it run. Here, since the electronic key 2 of this example is activated by noise having the band of CH1 or the driving radio wave Svv, even if the driving radio wave Svv is transmitted from the vehicle 1 by CH1, there is nothing regarding power supply to the electronic key 2. no problem. Therefore, the drive radio wave Svv is transmitted as it is on CH1, and only the request code Src is transmitted with the transmission frequency switched to CH2. The vehicle-side transmission frequency setting unit 20 corresponds to a master-side transmission channel switching unit.

  A plurality (two in this example) of outside-vehicle transmitters 8 are provided to transmit radio signals of different channels. The in-vehicle transmitter 8 of this example includes a CH1 out-of-vehicle transmitter 8a capable of transmitting a CH1 radio signal and a CH2 out-of-vehicle transmitter 8b capable of transmitting a CH2 radio signal. In addition, each of the outside transmitters 8a and 8b is provided with a power transmission processing unit 18 so that the driving radio wave Svv can be transmitted using a unique CH of each. The in-vehicle transmitter 9 includes a C1 in-vehicle transmitter capable of transmitting a CH1 radio signal and a CH2 in-vehicle transmitter capable of transmitting a CH2 radio signal, similarly to the out-of-vehicle transmitter 8. The transmitters 8a and 8b correspond to the signal transmitter.

  Therefore, for example, when the vehicle-side transmission frequency setting unit 20 confirms that no CH1 noise is generated in the communication environment of the electronic key system 3 at the time of outside-vehicle verification, the data of the drive radio wave Svv is transmitted to the CH1 outside-vehicle transmitter 8a. And the data of the request code Src are output, and both the driving radio wave Svv and the request code Src are transmitted from the CH1 in-vehicle transmitter 8a. In addition, when the vehicle-side transmission frequency setting unit 20 confirms that CH1 noise is generated in the communication environment of the electronic key system 3 at the time of outside-vehicle verification, for example, first, the driving radio wave Svv data is first transmitted to the outside of the CH1 vehicle. It outputs to the transmitter 8a and transmits the drive radio wave Svv from the CH1 in-vehicle transmitter 8a. After that, the verification ECU 7 outputs the request code Src data to the CH2 external transmitter 8b to transmit the request code Src from the CH2 external transmitter 8b, and the request code Src is electronically transmitted under the situation where the CH1 noise is generated. Let key 2 receive it.

  On the other hand, a plurality of (two in this example) key receivers 15 are provided to receive radio signals of different channels. The key receiver 15 of this example includes a CH1 key receiver 15a capable of receiving a CH1 radio signal and a CH2 key receiver 15b capable of receiving a CH2 radio signal. Each of these key receivers 15 a and 15 b is configured as an individual circuit group (component unit), and includes, for example, a band-pass filter 21 and a rectifier circuit 22. As described above, the key receivers 15a and 15b are composed of independent circuit groups because the electronic key 2 does not have a battery and moves by a driving radio wave Svv captured by radio waves. This is because the power is insufficient to switch the frequency.

  Further, the key receiver 15a is connected to the communication control unit 12 by a request code wiring Ha that is a take-out line for the request code Src and a drive radio wave wiring Hb that is a take-out line for the drive radio wave Svv. The request code wiring line Ha extends to the communication control unit 12 from between the band pass filter 21 and the rectifier circuit 22. The drive radio wave wiring Hb extends directly from the rectifier circuit 22 to the communication control unit 12. The key receiver 15b also has the same wiring structure as the key receiver 15a.

  The communication control unit 12 includes a key-side transmission frequency setting unit that sets the transmission frequency of the ID signal Sid based on which of the two key receivers 15a and 15b has received the request code Src (request signal Srq). 23 is provided. When the key side transmission frequency setting unit 23 confirms that the request code Src is received by the CH1 key receiver 15a, the key side transmission frequency setting unit 23 recognizes that the noise of the pair CH1 is not generated in the communication environment of the electronic key system 3, The transmission frequency of the ID signal Sid is set to CH1. On the other hand, when the key-side transmission frequency setting unit 23 confirms that the request code Src is received by the CH2 key receiver 15b, it recognizes that the noise of the pair CH1 is generated in the communication environment of the electronic key system 3. Thus, the transmission frequency of the ID signal Sid is set to CH2 that is not affected by this noise. The key-side transmission frequency setting unit 23 corresponds to terminal-side transmission channel switching means.

  Although the key transmitter 16 shares one transmitting antenna, it has two transmitting circuits, that is, a transmitting circuit for CH1 and a transmitting circuit for CH2, and one of these circuits selectively operates, so that CH1 and CH2 One radio signal can be transmitted. When the key-side transmission frequency setting unit 23 confirms that the electronic key 2 has received the request code Src on CH1, the key-side transmission frequency setting unit 23 executes the transmission operation of the ID signal Sid on the transmission circuit for CH1, thereby obtaining the ID signal Sid on the electronic key. 2 to CH1 frequency. Further, when the key-side transmission frequency setting unit 23 confirms that the electronic key 2 has received the request code Src by CH2, the key-side transmission frequency setting unit 23 executes the transmission operation of the ID signal Sid by the transmission circuit for CH2, thereby obtaining the ID signal Sid. The electronic key 2 is transmitted at the frequency of CH2.

Next, the operation of the electronic key system 3 of this example will be described with reference to FIGS.
First, as shown in FIGS. 2 and 4, a case is assumed in which no noise of the pair CH1 is generated in the communication environment of the electronic key system 3. As an operation performed by the key operation free system 6, the verification ECU 7 checks whether or not the electronic key 2 exists in the communication area of smart communication (external vehicle verification, in-vehicle verification). 9), a wake signal (wake pattern) 24 is intermittently transmitted as an RF band signal to form a communication area for the wake signal 24.

  For example, when performing outside verification, the wake signal 24 is intermittently transmitted from the outside transmitter 8 to the outside of the vehicle to form a communication area for the wake signal 24 around the vehicle. When performing in-vehicle collation, the wake signal 24 is transmitted from the in-vehicle transmitter 9 to the entire area of the vehicle to form a communication area for the wake signal 24 in the entire area of the vehicle. In the following description, an example of vehicle outside verification will be given. The wake signal 24 is a command to activate the electronic key 2 in the standby state (sleep state), and is repeatedly transmitted from the outside transmitter 8 at a predetermined constant interval.

  Further, the wake signal 24 of this example includes a drive radio wave Svv transmitted to the electronic key 2 as power of the electronic key 2 and a wake code as a function code that the own signal is the wake signal 24. Furthermore, in the case of this example, since the channel used in the normal state where CH1 noise is not generated is set to CH1, when no CH1 noise is generated in the communication environment of the electronic key system 3, the drive radio wave Svv Both the wake code and the wake code are transmitted from the CH1 outside transmitter 8a on the CH1. If the electronic key 2 can receive the driving radio wave Svv in the wake signal 24, the electronic key 2 switches from the stopped state to the power supply state in which power is supplied to the various components of the electronic key 2.

  In addition, the verification ECU 7 repeatedly executes a reception preparation operation for confirming which channel the radio signal is currently received by the tuner 10 in accordance with the transmission operation of the wake signal 24, that is, in a polling cycle. As a polling reception preparation operation, the verification ECU 7 of this example first performs a start-up operation for starting the tuner 10 that is on standby, and then performs a CH1 reception preparation operation, followed by a CH2 reception preparation operation. Do. Then, the verification ECU 7 repeats a series of operations such as a continuous startup operation → CH1 reception preparation operation → CH2 reception preparation operation in accordance with the transmission of the wake signal 24.

  The polling reception preparation operation (startup operation, CH1 reception preparation operation, CH2 reception preparation operation) is a predetermined constant determined from the wake pattern transmission so that a reply from the electronic key 2 can be received during the reception presence confirmation operation. It is set to start at a certain time. The startup operation is a very short time process, and is set to a short process time of, for example, several ms. In the CH1 reception preparation operation and the CH2 reception preparation operation, the reception confirmation time is set to the same time, and for example, is set longer than the bit length of the ACK reply by a predetermined time (for example, several tens of ms).

  When the electronic key 2 enters the communication area of the wake signal 24 and the wake signal 24 is received by the CH1 key receiver 15a, the electronic key 2 is switched from the previous stop state to the power supply state by the driving radio wave Svv in the wake signal 24. Change. Then, the electronic key 2 operates in accordance with the wake code that is read after the driving radio wave Svv, and enters the activated state as the electronic key 2 is turned on. At this time, since the electronic key 2 confirms that the wake code is received by CH1, the key side transmission frequency setting unit 23 sets the channel of various signals transmitted from the electronic key 2 to the vehicle 1 to CH1. Therefore, when the communication control unit 12 receives the wake code and enters the activated state, the communication control unit 12 returns the first ACK signal 25 to the vehicle 1 as the notification, but transmits this via CH1. In addition, the first ACK signal 25 is set to a transmission timing that reaches the vehicle 1 when the tuner 10 performs a CH1 reception preparation operation by polling.

  When CH1 noise is not generated, the verification ECU 7 at this time transmits the wake signal 24 and then receives the first ACK signal 25 in the subsequent CH1 reception preparation operation for polling. The verification ECU 7 confirms ACK reception by confirming the bit in the first ACK signal 25. The verification ECU 7 determines that the electronic key 2 exists in the communication area of smart communication when the ACK reply is normally received after the wake signal 24 is transmitted. In addition, when the verification ECU 7 normally accepts an ACK response in response to the wake signal 24, the verification ECU 7 ends the polling in that cycle, and thereafter, the electronic key 2 is set by the channel (here, CH1) established for communication at this time. Transition to an authentication operation to actually confirm whether it is a legitimate one. The reception preparation operation in this authentication operation is executed on CH1.

  Further, when the verification ECU 7 receives an ACK reply from the electronic key 2 after the wake pattern is transmitted, the verification ECU 7 subsequently transmits a vehicle ID signal 26 as its own vehicle code from the CH1 external transmitter 8a through CH1. The vehicle ID signal 26 includes the drive radio wave Svv described above and a vehicle ID that is a unique ID code of the vehicle. When the vehicle ID signal 26 is received by the CH1 key receiver 15a, the electronic key 2 is supplemented with power by the driving radio wave Svv included in the vehicle ID signal 26, and the continuation of the subsequent operation is ensured. And the communication control part 12 performs the reading operation | movement of vehicle ID following this drive electric wave Svv.

  When the electronic key 2 receives the vehicle ID from the vehicle 1, the electronic key 2 checks the vehicle ID as a confirmation to see whether or not the vehicle ID is a normal code. At this time, the vehicle 1 performing smart communication is a regular vehicle. It is determined whether or not there is. As described above, the vehicle ID is transmitted from the vehicle 1 to the electronic key 2 and the vehicle type is determined by the electronic key 2. The situation is that there are a plurality of vehicles around the electronic key 2 and wireless signals are received from these vehicles. This is because smart communication is performed only with a regular vehicle. When the electronic key 2 recognizes that the vehicle ID verification has been established, the electronic key 2 sends an ACK reply from the key transmitter 16 to the vehicle 1 via CH1 to notify the fact. The second ACK signal 27 takes the same bits as the first ACK signal 25.

  After sending the vehicle ID signal 26, the verification ECU 7 performs an ACK reception preparation operation after a predetermined time as a reception preparation operation during the authentication operation. This ACK reception preparation operation is a reception preparation operation for receiving a CH1 radio signal, and includes a start-up operation and a CH1 reception preparation operation, and at a timing at which the second ACK signal 27 transmitted from the electronic key 2 can be received. The startup time is set. The verification ECU 7 recognizes that vehicle ID verification has been established with the electronic key 2 when it receives the second ACK signal 27 during the CH1 reception preparation operation of the ACK reception preparation operation after transmitting the vehicle ID signal 26. Then, it recognizes that the electronic key 2 existing in the communication area of smart communication is paired with itself.

  When the verification ECU 7 confirms that the vehicle ID verification is established, the verification ECU 28 subsequently transmits an authentication signal 28 for challenge response authentication from the CH1 external transmitter 8a via CH1. The authentication signal 28 includes the drive radio wave Svv, the challenge code used as a random number at the time of authentication, and the key number (several bit data) of the electronic key 2 registered on the vehicle 1 side. If the electronic key 2 can receive the authentication signal 28 by the CH1 key receiver 15a within a predetermined time after transmitting the second ACK signal 27, the electronic key 2 recognizes that the ACK reply has succeeded in CH1. When the electronic key 2 receives the authentication signal 28 from the vehicle 1, the electric key 2 is replenished with the driving radio wave Svv included in the authentication signal 28, and the continuation of the subsequent operation is ensured.

  In addition, when the challenge response authentication is performed, the key number of the electronic key 2 is transmitted from the vehicle 1 to the electronic key 2 and the electronic key 2 is checked for the key number in the vicinity of both the master key and the sub key. Since there is a possibility that interference will occur if they perform smart communication at the same time, by sending a key number from the vehicle 1 side and specifying the communication target of the smart communication at that time To prevent this kind of interference. When the communication control unit 12 receives the authentication signal 28, the communication control unit 12 compares the key number included in the authentication signal 28 with its own, and checks whether or not the communication control unit 12 is the communication target of the smart communication at this time. to decide.

  Furthermore, the electronic key 2 that has been confirmed that the number verification has been established then proceeds to create a response to the challenge code. At this time, the communication control unit 12 adds a special calculation to the challenge code included in the authentication signal 28 using the encryption key registered in the electronic key 2, and generates this as a response code. And the communication control part 12 transmits the response signal 29 containing this response code and ID code registered into the electronic key 2 from the key transmitter 16 by CH1.

  After transmitting the authentication signal 28, the verification ECU 7 starts a response reception preparation operation after a predetermined time as a reception preparation operation during the authentication operation. The response reception preparation operation includes the above-described startup operation and the CH1 reception preparation operation for confirming reception of the signal of the CH1, and the activation time is set at a timing at which the response signal 29 transmitted from the electronic key 2 can be received. Has been. When the verification ECU 7 transmits the authentication signal 28 and then receives the response signal 29 during the response reception preparation operation, the verification ECU 7 compares the ID code included in the response signal 29 with that registered in the vehicle 1. Perform verification. If these ID codes match, it is recognized that ID code verification is established.

  Further, when sending the challenge code to the electronic key 2, the verification ECU 7 adds a special calculation to the challenge code to calculate a response. Then, when the verification ECU 7 receives the response signal 29 by the tuner 10, the response code in the response signal 29 is compared with the one calculated by itself so that the electronic key 2 of the communication partner can be confirmed. Check if they are paired. When these response codes match, the verification ECU 7 confirms that response verification is established. When the verification ECU 7 confirms that all of the above-described series of verifications are established, the verification ECU 7 regards the smart verification as being established and permits or executes various operations such as door lock locking / unlocking and engine starting.

  When the verification ECU 7 confirms that the smart verification has been established, the verification ECU 7 transmits an end code signal 30 to that effect from the CH1 external transmitter 8a via CH1. This end code includes the drive radio wave Svv described above and an end code as a function code for causing the electronic key 2 to end smart communication. If the electronic key 2 receives the end code signal 30 by the CH1 key receiver 15a within a predetermined time after the response signal 29 is transmitted, the electronic key 2 recognizes that smart communication has been established and ends the smart communication. Further, when the electronic key 2 receives the end code signal 30, power is supplemented by the driving radio wave Svv included in the end code signal 30.

  On the other hand, as shown in FIGS. 3 and 5, when the electronic key 2 performs smart communication with the vehicle 1, as noise affecting the CH 1, for example, the radio signal of the CH 1 having the same frequency as the CH 1 is canceled. Assume that random noise (also referred to as unformatted noise) having such an intensity occurs. Here, when CH1 noise is generated in the communication environment, the tuner 10 is in an operation state of receiving CH1 noise during the polling CH1 reception preparation operation. For this reason, the noise monitoring unit 19 determines that there is CH1 noise in the communication environment by performing an operation in which a radio signal conforming to CH1 cannot be normally received, and notifies the vehicle side transmission frequency setting unit 20 that there is CH1 noise. Output.

  When the notification of presence of CH1 noise is input from the noise monitoring unit 19, the vehicle-side transmission frequency setting unit 20 switches the channel used for data transmission to another channel that is not affected by noise. In the case of this example, the vehicle-side transmission frequency setting unit 20 switches the signal group related to the request code Src to CH2 for transmission while keeping the transmission frequency of the drive radio wave Svv as CH1. The request code Src corresponds to the wake code, vehicle ID, challenge code, key number, and end code described above. For this reason, when the notification with the CH1 noise is input from the noise monitoring unit 19, the verification ECU 7 transmits only the wake code as the wake signal 24 from the CH2 vehicle-side transmitter 8 b with CH2. As a result, even if CH1 noise is generated in the communication environment of the electronic key system 3, the wake signal 24 at this time is transmitted by CH2 which is not affected by this, so the wake signal 24 is a problem with the electronic key 2. It arrives without.

  At this time, the verification ECU 7 continues the transmission of the drive radio wave Svv from the CH1 external transmitter 8a as shown in FIG. 5 while transmitting the wake signal 24 from the CH2 external transmitter 8b. By the way, when CH1 noise occurs in the communication environment of smart communication, the electronic key 2 is always in a state of acquiring power by the CH1 noise. Therefore, when CH1 noise is generated, there is no problem if power supply is relied on CH1 noise and only the signal group of the request code Src is transmitted. Therefore, if this communication format is adopted, the time for power transmission is omitted, which is highly effective for shortening the communication time. However, there is a possibility that CH1 noise may be intermittently generated in some cases. In this example, the transmission of the driving radio wave Svv from the transmitter 8a is continued so that power is applied to the electronic key 2 at this time as well. The For this reason, both shortening of the communication time of smart communication and stable power supply to the electronic key 2 can be achieved.

  When the electronic key 2 receives the wake signal 24 by the CH2 key receiver 15b, the electronic key 2 operates in accordance with the received CH2 wake signal 24, thereby switching the state from the standby state until then to the activated state. When the key-side transmission frequency setting unit 23 confirms that the wake signal 24 is received by the CH2 key receiver 15b, the key-side transmission frequency setting unit 23 determines that CH1 noise is generated in the communication environment of smart communication. The transmission frequency when transmitting various signals to the vehicle 1 is switched from the previous CH1 to CH2.

  When the communication control unit 12 enters the activation state by receiving the wake signal 24, the communication control unit 12 returns a first ACK signal 25 to the vehicle 1 to notify the vehicle 1 of this, but the first ACK signal 25 at this time is set to CH2. send. Therefore, even if CH1 noise is generated in the communication environment of smart communication, the first ACK signal 25 is transmitted on CH2 which is not affected by the noise, and thus reaches the vehicle 1 without any problem. In addition, the first ACK signal 25 is set to a transmission timing that reaches the vehicle 1 when the tuner 10 takes a CH2 reception preparation operation by polling.

  When CH1 noise is generated, the verification ECU 7 transmits the wake signal 24 and then receives the first ACK signal 25 in the subsequent CH2 reception preparation operation for polling. The verification ECU 7 determines that the electronic key 2 exists in the communication area of smart communication when the ACK reply is normally received after the wake signal 24 is transmitted. In addition, when the verification ECU 7 normally accepts an ACK response in response to the wake signal 24, the verification ECU 7 ends polling at that cycle, and thereafter, the electronic key 2 is set by the channel (here, CH2) established for communication at this time. Transition to an authentication operation to actually confirm whether it is a legitimate one. In addition, the reception preparation operation | movement in the authentication operation | movement at this time is performed by CH2.

  Then, the verification ECU 7 transmits only the vehicle ID as the vehicle ID signal 26 from the CH2 vehicle transmitter 8b while transmitting the driving radio wave Svv from the CH1 vehicle transmitter 8a. Therefore, even if CH1 noise is generated in the communication environment of smart communication, the second ACK signal 27 is transmitted on CH2 that is not affected by the noise, so that it reaches the vehicle 1 without any problem. Further, since the vehicle ID signal 26 is immediately transmitted from the vehicle 1 without waiting for the transmission of the driving radio wave Svv, the electronic key 2 transmits the vehicle ID signal 26 without any time from the first ACK signal 25 being transmitted. Receive. When the electronic key 2 receives the vehicle ID signal 26 transmitted from the vehicle 1 by the CH2 key receiver 15b, the electronic key 2 executes vehicle ID collation, and if this collation is established, the second ACK signal indicates that the collation is established. 27 is transmitted from the key transmitter 16 through CH2.

  In addition, after transmitting the vehicle ID signal 26, the verification ECU 7 performs an anti-ac reception preparation operation after a predetermined time as a reception preparation operation during the authentication operation. The ACK reception preparation operation at this time includes a startup operation and a CH2 reception preparation operation, and the activation time is set at a timing at which the second ACK signal 27 transmitted from the electronic key 2 can be received. The verification ECU 7 recognizes that vehicle ID verification has been established with the electronic key 2 when it receives the second ACK signal 27 during the CH2 reception preparation operation of the ACK reception preparation operation after transmitting the vehicle ID signal 26. Then, it recognizes that the electronic key 2 existing in the communication area of smart communication is paired with itself.

  When the verification ECU 7 confirms that the vehicle ID verification has been established, the CH2 vehicle transmitter 8b transmits the challenge code and the key number signal group as the authentication signal 28 while transmitting the driving radio wave Svv from the CH1 vehicle transmitter 8a. . Therefore, even if CH1 noise occurs in the communication environment of smart communication, the authentication signal 28 is transmitted by CH2 which is not affected by this, so that it reaches the electronic key 2 without any problem. When the electronic key 2 receives the authentication signal 28 by the CH2 key receiver 15b, the electronic key 2 first performs number verification, and if this number verification is established, generates a response code from the challenge code. And the communication control part 12 transmits the response signal 29 which consists of a response code and ID code from the key transmitter 16 by CH2. Therefore, even if CH1 noise is generated in the communication environment of smart communication, the response signal 29 is transmitted by CH2 which is not affected by the noise, and thus reaches the vehicle 1 without any problem.

  After transmitting the authentication signal 28, the verification ECU 7 starts a response reception preparation operation after a predetermined time as a reception preparation operation during the authentication operation. This response response preparation operation includes the startup operation described above and the CH2 reception preparation operation for confirming reception of the signal of CH2, and the activation time is set at a timing at which the response signal 29 transmitted from the electronic key 2 can be received. Has been. When the verification ECU 7 transmits the authentication signal 28 and then receives the response signal 29 during the response reception preparation operation, the verification ECU 7 first compares the ID code included in the response signal 29 with that registered in the vehicle 1. Code verification is performed, and if these ID codes match, it is recognized that ID code verification is established. Further, the verification ECU 7 confirms the establishment of the ID code verification, subsequently performs response verification, and recognizes the response verification if the response code received from the electronic key 2 matches that generated by itself. When the verification ECU 7 confirms that all of the above-described series of verifications are established, the verification ECU 7 regards the smart verification as being established and permits or executes various operations such as door lock locking / unlocking and engine starting.

  When the verification ECU 7 confirms that the smart verification is established, the verification ECU 7 transmits an end code as the end code signal 30 from the CH2 external transmitter 8b while stopping the transmission of the driving radio wave Svv from the CH1 external transmitter 8a. Therefore, even if CH1 noise is generated in the communication environment of smart communication, the end code signal 30 is transmitted by CH2 which is not affected by this, so that it reaches the vehicle 1 without any problem. When the electronic key 2 receives the end code signal 30 by the CH2 key receiver 15b, the electronic key 2 recognizes that the smart verification has been established and ends the smart communication. The example in which CH1 noise is generated in the wireless communication environment has been described above. However, since the operation principle is the same when CH2 noise is generated, description thereof will be omitted.

  Now, in the electronic key system 3 as in this example in which the electronic key 2 does not have its own power source (battery) and the electronic key 2 moves with the driving radio wave Svv for power transmitted from the vehicle 1, the tuner 10 of the vehicle 1 When the CH1 noise is regularly monitored by the noise monitoring unit 19 and the CH1 noise is generated in the communication environment of smart communication, the power transmission is performed without change, but the data transmission is affected by the noise. Switch to CH2 that is not running. For this reason, since various communication data reaches each other's communication partner, smart communication can be established even if noise occurs in the communication environment.

According to the configuration of the present embodiment, the following effects can be obtained.
(1) The electronic key system 3 is a power transmission type in which the electronic key 2 is activated using the driving radio wave Svv transmitted from the vehicle 1 as power. For this reason, since it is not necessary to mount a power source such as a battery on the electronic key 2, it is possible to reduce the size and cost of the electronic key 2 accordingly. The electronic key system 3 is also of a multi-channel type that switches the transmission channel to CH2, which is not affected by noise, when noise for CH1, which is a normal use channel, is generated in the communication environment. Therefore, even if CH1 noise occurs in the communication environment of the electronic key system 3, the request code Src of the vehicle 1 can be received by the electronic key 2. As described above, in this example, it is possible to provide the electronic key system 3 with high noise resistance of wireless communication while reducing the size of the electronic key 2.

  (2) When the electronic key 2 receives the request code Src and returns the ID signal Sid to the vehicle 1, the request code Src is transmitted through the same channel as the channel of the request code Src. By the way, the fact that the electronic key 2 has received the request code Src transmitted from the vehicle 1 can be regarded as no occurrence of noise affecting the channel of the request code Src in the smart communication environment. Therefore, when the electronic key 2 returns the ID signal Sid to the vehicle 1 in response to the request code Src, if the electronic key 2 sends it back on the same channel as the request code Src, the vehicle 1 receives the ID signal Sid. The accuracy can be made higher.

  (3) When the transmitters 8 and 9 of the vehicle 1 are multi-channel compatible, the transmitters 8 and 9 are configured by transmitters 8a and 8b each manufactured as a single component (component unit). Therefore, when the transmission frequency of the request code Src is switched, the transmission channel of the request code Src is switched by a simple process of simply selecting which one of the transmitters 8 and 9 is used. be able to. In this case, when CH1 noise is generated in the communication environment of smart communication, it is possible to simultaneously transmit the drive radio wave Svv and the request code Src. Therefore, the transmission of the request code Src is the transmission of the drive radio wave Svv. No need to complete. Therefore, since the request code Src can be immediately transmitted during smart communication, the communication time can be shortened.

  (4) When the transmission channel of the request code Src is switched from CH1 to CH2, the transmission of the driving radio wave Svv from the transmitter 8a is continued. For this reason, when CH1 noise is generated in the communication environment of smart communication, the electronic key 2 takes a state in which the CH1 noise is activated by power, but this noise is generated intermittently. However, since the power is supplied by the driving radio wave Svv at the time of intermittent noise, the power supply can be filled. For this reason, since it becomes possible to always provide electric power to the electronic key 2, stable power supply to the electronic key 2 can be supported.

  (5) When the key receiver 15 is adapted for multiple channels, the key receiver 15 is constituted by receivers 15a and 15b each manufactured as a single component (component unit). By the way, for example, in order to switch the reception channel in one receiver, a large amount of power is required for this switching, and the electronic key 2 such as the present example having no battery has the possibility of causing instability in operation. Absent. However, as in this example, two independent receivers 15a and 15b are prepared, and if they can handle multi-channel reception, the reception channel can be multi-channeled without requiring large power. Can do.

Note that the embodiment is not limited to the configuration described so far, and may be modified as follows.
The driving radio wave Svv and the request code Src are not necessarily transmitted at the same time under the generation of CH1 noise. For example, as in the case where no CH1 noise is generated, a communication format in which the driving radio wave Svv is transmitted first and then the request code Src is transmitted may be adopted.

  The transmitter 8 (9) of the vehicle 1 is not necessarily limited to being composed of two transmitters 8a and 8b, each of which is independent as a part. That is, the transmitter 8 (9) of the vehicle 1 may be composed of one device and can be adapted to multiple channels by switching the transmission frequency of the transmission circuit therein. In this case, since the simultaneous transmission of the drive radio wave Svv and the request code Src is impossible, a communication format in which these are sequentially transmitted is taken. The same applies to the key receiver 15.

  The tuner 10 of the vehicle 1 and the key transmitter 16 of the electronic key 2 are not necessarily limited to a single device, and a plurality of independent parts groups such as the transmitter 8 (9) and the key receiver 15 are used. It may be composed of

  The electronic key 2 is not necessarily limited to having no power source such as a battery, and may be activated by holding a secondary battery. In this case, when the electronic key 2 receives the drive radio wave Svv, the secondary battery may be charged by the power of the drive radio wave Svv.

  When the electronic key 2 transmits the ID signal Sid to the vehicle 1, the transmission channel at this time is not necessarily limited to the same as the reception channel of the request code Src. That is, the ID signal Sid may be transmitted on a channel different from the request code Src.

  The electronic key system 3 is not necessarily limited to the key operation free system 6, and may be a wireless key system that requires button operation with the electronic key 2 when a function code is transmitted. The electronic key system 3 may have both of these systems.

The signal frequency used in the electronic key system 3 is not necessarily limited to that in the RF band, but a signal in the UHF band other than RF may be used, or the LF band may be used.
-The channel switching function on the electronic key 2 side is not always necessary and may be omitted.

  The vehicle operation that is permitted or executed when ID verification is established in the electronic key system 3 is not necessarily limited to locking / unlocking the door lock or starting the engine, but may be other operations.

  -If it is found that there is no CH1 noise in the communication environment, or if it is found that there is CH2 noise in the communication environment, the request code Src is transmitted by CH1, and the drive radio wave Svv is transmitted by CH2. It may be. Furthermore, the drive radio wave Svv may be transmitted by CH2 regardless of the presence or absence of noise in CH2.

The selectable channels are not necessarily limited to two types (CH1, CH2), and may be three or more types.
The mounting target of the power transmission type wireless communication system of this example is not necessarily limited to the electronic key system 3, and it goes without saying that it can be mounted on various other systems, devices, and apparatuses.

Next, technical ideas that can be grasped from the above-described embodiment and other examples will be described below together with their effects.
(1) The communication terminal according to any one of claims 1 to 3 , wherein the communication terminal is affected by the noise based on the transmission data, and a transmission channel of reply data transmitted by the communication terminal in response to the transmission data. Terminal-side outgoing channel designation means is provided for making outgoing calls with no channels. According to this configuration, even if noise is generated in the communication environment of wireless communication, it becomes possible for the communication master to receive reply data transmitted from the communication terminal.

(2) In any one of claims 1 to 3 and the technical idea (1), the signal transmitter of the communication master is individually provided for each channel of the transmission data. According to this configuration, a plurality of signal transmitters each functioning as a single component are provided for each transmission channel, and by selecting a specific one of these, a plurality of transmission channels of the communication master are selected. To a specific one. For this reason, it becomes possible to perform the switching of the transmission channel of the communication master by a simple process of selecting a plurality of transmitters each functioning as a single component.

(3) In any one of claims 1 to 3 and technical ideas (1) and (2), a signal receiver of the communication terminal is individually provided for each channel of the outgoing data. According to this configuration, when switching the reception channel of the communication terminal, it is only necessary to selectively switch which one of the plurality of signal receivers each functioning as a single component is used. It is possible to use a plurality of channels with less power.

(4) In any one of claims 1 to 3 and the technical ideas (1) to (3), the communication master communicates with the communication terminal a plurality of times by communicating with the communication terminal a plurality of times. One wireless communication is executed between the two. In this case, for example, the system having this configuration can be applied to a key operation free system which is a kind of electronic key system.

  (5) When the communication master performs wireless communication with the communication terminal, the communication terminal transmits the driving radio wave serving as the power of the communication terminal to the transmission data that conveys the contents of the data. In the power transmission wireless communication method for performing the wireless communication by causing the communication terminal to perform an operation based on the transmission data while operating, the presence or absence of noise in the communication environment of the wireless communication is monitored in the communication master, A power transmission type wireless communication method comprising: switching data transmission of the outgoing data to another channel that is not affected by the noise when the noise monitoring unit determines that there is noise.

(6) A communication master or a communication terminal used in the power transmission type wireless communication system according to claims 1 to 3 and the technical ideas (1) to (4).

The block diagram which shows schematic structure of the electronic key system in one Embodiment. The block diagram which shows the operation state of a system when CH1 noise has not generate | occur | produced. The block diagram which shows the operation | movement state of a system when CH1 noise has generate | occur | produced. The timing chart which shows the operation | movement transition of a system when CH1 noise has not generate | occur | produced. The timing chart which shows the operation | movement transition of a system when CH1 noise has generate | occur | produced.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle as a communication master, 2 ... Electronic key as a communication terminal, 3 ... Electronic key system as a power transmission type radio | wireless communications system, 8a, 8b ... Transmitter as a signal transmission part, 19 ... As noise monitoring means Noise monitoring unit, 20 ... transmission frequency setting unit as master side transmission channel switching means, 23 ... key side transmission frequency setting unit as terminal side transmission channel switching means, CH1, CH2 ... channel, Src ... transmission data (data content) Request code, Svv ... driving radio wave, Sid ... ID signal as reply data.

Claims (3)

When the communication master performs wireless communication with the communication terminal, the communication data is transmitted to the transmission data that conveys the contents of the data, and the drive radio wave serving as the power of the communication terminal is also transmitted, thereby operating the communication terminal with the drive radio wave. In the power transmission type wireless communication system for performing the wireless communication by causing the communication terminal to perform an operation based on the outgoing data,
Noise monitoring means for monitoring the presence or absence of noise in the communication environment of the wireless communication in the communication master;
When the noise monitoring means determines that there is noise, the master side transmission channel switching means for switching the transmission of the transmission data to another channel not affected by the noise ,
The master-side transmission channel switching unit transmits the transmission data from a signal transmission unit capable of transmitting a radio signal of a channel that is not affected by the noise when the noise monitoring unit determines that there is noise. A power transmission type radio communication system, characterized in that the driving radio wave is maintained while being transmitted from a signal transmission unit that transmits a radio signal of a channel affected by the above .   The communication terminal is provided with terminal-side transmission channel switching means for setting a transmission channel of reply data transmitted by the communication terminal in response to the transmission data as a transmission channel of the transmission data. The power transmission type wireless communication system according to claim 1.   An electronic key that transmits a unique key code by wireless communication is used as the communication terminal. When the communication master receives the key code transmitted from the electronic key, the key is checked against that of the communication master. The power transmission type wireless communication system according to claim 1, wherein the power transmission type wireless communication system is applied to an electronic key system that executes collation.

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