JP2013217103A - Electronic key system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic key system in which the time required for the communication of ID collation can be shortened in a key response combination position determination system.SOLUTION: In an electronic key system, a response combination of electronic keys 2 to radio waves transmitted from transmitters 4-6 is confirmed, thereby performing ID collation on the electronic keys 2 while grasping key positions. In polling, the transmitters 4-6 transmit a radio wave while applying antenna codes C1-C3 to a wake signal Swk. Upon receiving the wake signal Swk, the electronic key 2 reads the antenna codes C1-C3 to determine the transmitters 4-6 from which the radio wave is received and transmits reception code information Dac that is a determination result, while applying it to an ack signal Sack that is a response of the wake signal Swk. Based on the reception code information Dac which is received together with the ack signal Sack, a vehicle sets the transmitters 4-6 to be used for subsequent smart communication.

Description

  The present invention relates to an electronic key system that determines the position of an electronic key by a combination of key responses and performs ID collation with the electronic key wirelessly.

  As is well known in the art, many vehicles are equipped with an electronic key system that wirelessly transmits an electronic key ID to the vehicle from an electronic key and performs ID verification with the electronic key. In this type of electronic key system, a key operation-free system that periodically transmits a request from a vehicle transmitter and performs ID verification (smart verification) in the vehicle on the electronic key ID transmitted by the electronic key as a response to the request. There is.

  In the case of this key operation free system, for example, a plurality of in-vehicle transmitters are installed on each outside handle knob of the vehicle door, and a plurality of in-vehicle transmitters are also installed on the floor inside the vehicle. And if the vehicle outside smart collation performed in response to the request from the vehicle outside transmitter is established, the door locking / unlocking operation is permitted / executed. In addition, if an in-vehicle smart verification that is triggered by a request from the in-vehicle transmitter is established, a power transition operation (engine start operation) by an engine switch in the driver's seat is permitted.

  As a kind of this key operation free system, there is a key response combination position determination method in which a key position is determined by a response combination of an electronic key with respect to a radio wave transmitted from each transmitter of a vehicle and smart matching is performed (Patent Document 1, Patent Document 1). 2). In the case of the key response combination position determination method, for example, a vehicle body right part transmitter that forms a communication area around the driver's seat door (outside / inside of the vehicle) is provided at the right side of the vehicle body, and the passenger's door around the passenger seat (outside / inside of the vehicle) ) Provide a vehicle body right side transmitter that forms a communication area in the area. Each request is transmitted from these transmitters, and the outside / outside of the electronic key is determined based on a combination of responses of the electronic key to the request. The key response position determination formula has the advantage that the number of transmitters used is small.

JP 2004-84406 A JP 2005-76329 A

  By the way, the communication sequence of smart collation has the following aspects, for example. First, a wake signal is periodically transmitted from the vehicle transmitter to confirm whether or not the electronic key has approached the vehicle. When the electronic key approaches the vehicle and receives a wake signal, the electronic key is activated and transmits an ACK signal to the vehicle. When the vehicle receives the ACK signal, it performs challenge response authentication with the electronic key, and confirms that the challenge response authentication and the key ID verification of the electronic key ID transmitted from the electronic key are established, the smart verification is established. And

  For this reason, in the case of the key response position determination formula, it is necessary to perform the above-described smart verification of the communication sequence in each transmitter. Therefore, the time required for the smart collation becomes long, and this has a problem that leads to concern about deterioration in response. In addition, if the number of transmitters to be installed increases, this problem becomes more prominent, and some countermeasures are necessary.

  An object of the present invention is to provide an electronic key system capable of shortening the time required for ID verification communication in a key response combination position determination method.

  In order to solve the above problems, in the present invention, a radio wave for confirming the presence of an electronic key is transmitted from a plurality of transmitters provided in a communication master, and transmitted from the electronic key in response to the radio wave. The validity of the electronic key ID is verified by determining the position of the electronic key based on the combination of the response of the electronic key to the radio wave from the transmitter, and if the ID verification is established, the operation of the communication master is permitted. Alternatively, in the electronic key system to be executed, the antenna information adding means that is provided in the communication master and adds antenna information for notifying which radio wave is transmitted from each transmitter to each radio wave transmitted from each transmitter. And determining from which transmitter the radio wave is received based on the antenna information, and the radio wave reception information as a result of the determination is transmitted in advance. Reception information notifying means for notifying the communication master, and transmitter setting means for setting a transmitter provided in the communication master and used for communication with the electronic key based on the radio wave reception information. The gist.

  According to the configuration of the present invention, the communication master gives antenna information to the radio wave when the transmitter transmits the radio wave. The electronic key determines from which transmitter the received radio wave is transmitted based on the received antenna information, and transmits the radio wave reception information as the determination result to the communication master. The communication master confirms the transmitter that has made communication from the received radio wave reception information, and sets the transmitter to be used for communication with the electronic key. Thereby, it becomes possible to perform communication only with the transmitter in which the electronic key is located within the area among the plurality of transmitters. Therefore, communication can be performed without waste, and communication time can be shortened.

  In the present invention, the ID verification periodically transmits a wake signal from the communication master, and when the electronic key receives and activates the wake signal, transmits an ACK signal to the communication master. When the ACK signal is received, the communication master and the electronic key start communication, and the antenna information adding unit adds the antenna information to the wake signal and transmits the wake signal from the communication master to the electronic key. The reception information notifying unit assigns the radio wave reception information to the ACK signal and transmits the signal from the electronic key to the communication master, and the transmitter setting unit performs subsequent communication based on the radio wave reception information. The gist is to set the transmitter to be used. According to this configuration, since the transmitter to be used is set in the process of exchanging the wake signal and the ACK signal performed at the initial stage of the ID collation communication, an optimal transmitter can be set at the beginning of communication. It becomes possible. Therefore, the effect of shortening the communication time for ID verification is increased.

  The gist of the present invention is that the wake signal is simultaneously transmitted from the plurality of transmitters, and the antenna information is transmitted from the plurality of transmitters at different transmission timings. According to this configuration, since interference of antenna information is less likely to occur, the effect of ensuring communication establishment is enhanced.

  In the present invention, when the transmitter setting means confirms that the electronic key is located in an overlapping area where communication areas of the plurality of transmitters overlap with each other, the transmitter setting unit is set in advance among the plurality of transmitters that establish communication. The gist is to set the transmitter to be used in accordance with the set priority. According to this configuration, it is possible to set which transmitter is used when the electronic key is located in an overlapping area where the communication areas of the transmitters overlap. Therefore, when the electronic key is located in the overlapping area, the transmitter to be used can be specified, which further contributes to shortening of the communication time.

  According to the present invention, in the key response combination position determination method, the time required for ID collation communication can be shortened.

The block diagram of the electronic key system of 1st Embodiment. The conceptual diagram of the communication area which each transmitter of a vehicle forms. The timing chart which shows the transmission timing of the antenna code transmitted from each transmitter. The conceptual diagram of the receiving code information which an electronic key transmits. The timing chart which shows the communication sequence of smart collation outside a vehicle. The timing chart which shows the communication sequence of in-vehicle smart collation. The schematic block diagram of the electronic key of 2nd Embodiment. The timing chart which shows the transmission timing of the reception code information and key identification information which are transmitted from each electronic key. The timing chart which shows the communication sequence of smart collation when two or more electronic keys exist.

(First embodiment)
Hereinafter, a first embodiment of an electronic key system embodying the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the vehicle 1 is provided with an electronic key system 3 that performs ID verification with the electronic key 2 in response to communication from the vehicle 1. The electronic key system 3 of this example performs smart communication with the electronic key 2 by narrow area wireless communication (communication distance: several meters), and when ID verification (smart verification) by this smart communication is established, various operations of the vehicle 1 are performed. It is a key operation free system that permits / executes. In addition, the key operation free system of this example is a key response combination position for performing smart verification by determining the position of the electronic key 2 based on the response combination of the electronic key 2 to radio waves transmitted from the transmitters 4 to 6 of the vehicle 1. It is also a judgment method. The vehicle 1 corresponds to a communication master.

  The vehicle 1 is provided with a verification ECU (Electronic Control Unit) 7 that performs ID verification with the electronic key 2, a body ECU 8 that manages the power source of the on-vehicle electrical components, and an engine ECU 9 that controls the engine 10. They are connected through the bus 11. The electronic key ID registered in the electronic key 2 is written and stored in the memory of the verification ECU 7.

  As shown in FIGS. 1 and 2, the vehicle 1 includes a vehicle body right side transmitter 4 capable of transmitting radio waves in the LF (Low Frequency) band around the right side of the vehicle body (including outside and inside the vehicle), A vehicle body left side transmitter 5 capable of transmitting LF radio waves to the entire area around the left side (including outside / inside the vehicle), and a luggage transmitter 6 capable of transmitting LF radio waves to the entire area around the luggage area (including outside / inside the vehicle) , A vehicle receiver 12 capable of receiving radio waves in the UHF (Ultra High Frequency) band is provided, and these are connected to the verification ECU 7.

  The electronic key 2 is provided with a key control unit 13 that controls the operation of the electronic key 2. A key-specific electronic key ID is registered in the memory of the key control unit 13. The key control unit 13 is connected to a receiving unit 14 capable of receiving LF radio waves and a transmitting unit 15 capable of transmitting UHF radio waves.

  As shown in FIG. 2, in the vehicle 1, a communication area E <b> 1 of the vehicle body right part transmitter 4 is formed around the right side of the vehicle body and a communication area E <b> 2 of the vehicle body left part transmitter 5 is formed around the left side of the vehicle body. Thus, a communication area E3 is formed around the luggage area of the vehicle body. In this example, the following seven areas (regions) are constructed by these three communication areas E1 to E3.

(A) Driver's seat side outside area Ea: Area constructed by the vehicle body right side transmitter 4 alone (b) Passenger seat side vehicle outside area Eb: Area constructed by the vehicle body left side transmitter 5 alone (c) Luggage side vehicle exterior Area Ec: Area constructed by luggage transmitter 6 alone (d) First overlap area Ed: Area where radio waves of transmitters 4 and 5 overlap (e) Second overlap area Ee: Each of transmitters 4 and 6 Area where radio waves overlap (f) Third overlap area Ef: Area where radio waves of transmitters 5 and 6 overlap (g) Fourth overlap area Eg: Area where radio waves of three transmitters 4 to 6 overlap The electronic key system 3 of the example determines the position (outside / inside the vehicle) of the electronic key 2 by confirming the response combination of the electronic key 2 to the radio waves transmitted from the transmitters 4 to 6. For example, when the electronic key 2 responds only to the radio waves transmitted from the vehicle body right side transmitter 4 with respect to the radio waves transmitted from the transmitters 4 to 6, the electronic key 2 is located in the driver seat side outside area Ea. Determined. In addition, when there is a response of the electronic key 2 to the radio waves transmitted from the transmitters 4 to 6 to the radio waves from the vehicle body right side transmitter 4 and the vehicle body left side transmitter 5, the electronic key 2 is the first overlap. It is determined that it is located in the area Ed.

  When the vehicle 1 confirms that ID verification (smart vehicle verification) is established between the electronic key 2 and the outside of the vehicle, the vehicle ECU 8 permits / executes the door lock locking / unlocking by the body ECU 8. Further, when the vehicle 1 confirms that the ID verification (in-vehicle smart verification) is established in the vehicle with the electronic key 2, the vehicle 1 permits the power transition operation (engine start operation) by the engine switch 16 in the driver's seat.

  As shown in FIG. 1, the electronic key system 3 of this example is provided with a communication time shortening function for shortening the communication time of smart communication. The communication time shortening function of this example adds a unique antenna code C to the radio waves transmitted from the transmitters 4 to 6, and indicates which transmitter 4 to 6 the electronic key 2 has received the radio waves to the electronic key 2. Let me grasp. Then, the transmitter that has established communication with the electronic key 2 is notified from the electronic key 2 to the vehicle 1 in the process of smart communication, and only with the transmitters 4 to 6 that have established communication with the electronic key 2. The communication time is shortened by continuing the communication. The antenna code C corresponds to antenna information.

  As shown in FIG. 1, the verification ECU 7 is provided with an antenna code applying unit 17 that applies the unique antenna codes C1 to C3 of the transmitters 4 to 6 to the radio waves transmitted from the transmitters 4 to 6. ing. As shown in FIG. 3, the antenna code assigning unit 17 assigns unique antenna codes C1 to C3 to the wake signals Swk transmitted from the transmitters 4 to 6, respectively. C3 is notified to the electronic key 2. The antenna codes C1 to C3 are transmitted from the transmitters 4 to 6 at different transmission timings. The antenna code providing unit 17 corresponds to antenna information providing means.

  As shown in FIG. 1, the key control unit 13 is provided with a reception code notification unit 18 that notifies the vehicle 1 what the antenna code C received in the electronic key 2 is. As shown in FIG. 4, the reception code notifying unit 18 returns reception code information Dac indicating what the antenna code C is received by the electronic key 2 as a response to the wake signal Swk in the process of smart communication. By adding to Sack, the vehicle 1 is notified. The reception code notification unit 18 corresponds to reception information notification means, and the reception code information Dac corresponds to radio wave reception information.

  As shown in FIG. 1, the verification ECU 7 is provided with a use transmitter setting unit 19 that sets the transmitters 4 to 6 to be used in the subsequent smart communication based on the received code information Dac notified from the electronic key 2. It has been. The used transmitter setting unit 19 sets a transmitter to be used in accordance with a predetermined priority when the electronic key 2 is located in a region where communication areas overlap. The used transmitter setting unit 19 corresponds to transmitter setting means.

Next, the operation of the electronic key system 3 of this example will be described with reference to FIGS.
[When the electronic key 2 is located in the area Ea outside the driver's side vehicle]
As shown in FIG. 5, the verification ECU 7 sequentially monitors whether or not the electronic key 2 has approached the vehicle 1 by a polling operation in which the wake signal Swk is periodically transmitted by LF. The verification ECU 7 transmits the wake signal Swk simultaneously from the transmitters 4 to 6.

  At this time, the antenna code assigning unit 17 assigns the antenna codes C1 to C3 to the wake signals Swk transmitted from the transmitters 4 to 6, respectively, and causes the transmitters 4 to 6 to transmit the wake signals Swk. In the case of this example, the antenna code C1 is given to the wake signal Swk of the vehicle body right side transmitter 4, the antenna code C2 is given to the wake signal Swk of the vehicle body left side transmitter 5, and the wake signal Swk of the luggage transmitter 6 is added. An antenna code C3 is given. The antenna codes C1 to C3 are transmitted at different timings so as not to interfere on the electronic key 2 side. In the case of this example, the antenna codes C1 to C3 are continuously transmitted at different timings in the order of C1 → C2 → C3.

  When the electronic key 2 approaches the vehicle 1, the radio key 2 receives radio waves corresponding to the position at that time among radio waves transmitted from the transmitters 4 to 6. Here, since the example in which the electronic key 2 is located in the area Ea, that is, the example in which it is located outside the vehicle is assumed, the electronic key 2 receives the wake signal Swk and the antenna code C1 transmitted from the vehicle body right part transmitter 4. Receive.

  The electronic key 2 is activated by the received wake signal Swk and starts operating. At this time, the reception code notification unit 18 reads the antenna code C1 received by the electronic key 2 and confirms that the radio wave transmission source is the vehicle body right side transmitter 4.

  The electronic key 2 transmits an ack signal Sack to the vehicle 1 by a UHF radio wave as a response to the wake signal Swk. At this time, the reception code notifying unit 18 adds reception code information Dac for notifying which transmitter 4 to 6 has received the radio wave from the electronic key 2 to the ACK signal Sack and transmits it by the UHF radio wave. Here, since the example in which the electronic key 2 is located in the area Ea is assumed, the electronic key 2 is a reception code for notifying that the radio wave received by the electronic key 2 is the radio wave from the vehicle body right part transmitter 4. The information Dac is added to the ACK signal Sack and transmitted.

  The reception code information Dac is constructed from, for example, a bit signal of several bits (for example, 3 bits), and the code length is set to be constant. The bit combination of “0” and “1” indicates which transmitter 4 to 6 has received the radio wave. For example, the reception code information Dac is “001” when radio waves are received only from the vehicle body right side transmitter 4, “010” when radio waves are received only from the vehicle body left side transmitter 5, and when radio waves are received only from the luggage transmitter 6. It is represented by “100”. The reception code information Dac is “011” when radio waves are received from the vehicle body right side transmitter 4 and the vehicle body left side transmitter 5, and “101” when radio waves are received from the vehicle body right side transmitter 4 and the luggage transmitter 6. It is represented by “110” when radio waves are received from the left body transmitter 5 and the luggage transmitter 6 and “111” when radio waves are received from the three transmitters 4 to 6.

  The verification ECU 7 receives the ACK signal Sack and the received code information Dac transmitted from the electronic key 2 at the vehicle receiver 12. The verification ECU 7 confirms that the electronic key 2 exists in the vicinity of the vehicle 1, that is, that smart communication is established, when receiving a reply of the ack signal Sack within a certain time after the transmission of the wake signal Swk.

  When the vehicle 1 receives the ACK signal Sack, the use transmitter setting unit 19 reads the reception code information Dac given to the ACK signal Sack. Here, since it is assumed that the electronic key 2 is located in the area Ea, the transmitter setting unit 19 reads the received code information Dac of “001”. Therefore, the use transmitter setting unit 19 recognizes that the electronic key 2 exists in the area Ea, that is, outside the driver's seat side vehicle, and sets the transmitter to be used in the subsequent smart communication to the vehicle body right side transmitter 4. Set.

  The verification ECU 7 transmits a verification code Sch from the vehicle body right side transmitter 4 set as the transmitter used. The verification code Sch includes, for example, a vehicle ID, a key number, a challenge code, and the like. The vehicle ID is a unique ID of each vehicle 1 set for each vehicle 1. The key number is number information assigned to each electronic key 2 in the order of registration so that the plurality of electronic keys 2 registered in the vehicle 1 can be identified. The challenge code is a random number having a different value each time it is generated.

  Upon receiving the verification code Sch, the key control unit 13 performs key number authentication for confirming the key number and vehicle ID verification for confirming the coincidence of the vehicle ID. When the key control unit 13 confirms the establishment of the key number authentication and the vehicle ID verification, the key control unit 13 generates a response code by passing the challenge code through its encryption key, and transmits the response code Srs for the verification code Sch to the vehicle 1 by UHF. The response code Srs includes a response code, an electronic key ID, and the like. The response code is a response code calculated by the electronic key 2. The electronic key ID is an ID unique to the key registered in the electronic key 2.

  The verification ECU 7 creates a response code in the same manner by passing the generated challenge code through its own encryption key. When the verification ECU 7 receives the response code Srs from the electronic key 2, the verification code verification confirms the validity of the response code in the response code Srs, and the electronic key ID confirms the validity of the electronic key ID in the response code Srs. Check. When the verification ECU 7 confirms that the response code verification and the electronic key ID verification are established, the verification ECU 7 establishes the smart verification.

  At this time, the verification ECU 7 recognizes that the electronic key 2 is in the area Ea based on the reception code information Dac of “001” received from the electronic key 2, that is, the electronic key 2 is outside the driver's seat side vehicle. . Therefore, the verification ECU 7 recognizes that the smart verification outside the vehicle on the driver's seat side is established, and permits / executes the door lock locking / unlocking by the body ECU 8, for example.

[When the electronic key is located in the area Ed in the car]
FIG. 6 assumes an example where the electronic key 2 is located in the area Ed, that is, an example where the electronic key 2 is located in the vehicle. Therefore, in this case, the electronic key 2 receives the wake signal Swk and the antenna code C1 transmitted from the vehicle body right side transmitter 4, and the wake signal Swk and the antenna code C2 transmitted from the vehicle body left side transmitter 5. Received by the unit 14.

  The electronic key 2 is activated by the received wake signal Swk and starts operating. At this time, the electronic key 2 receives the wake signal Swk from both the vehicle body right side transmitter 4 and the vehicle body left side transmitter 5, but since the signals have the same contents, there is a change in the intensity of radio wave reception. However, it can be received as usual.

  The antenna code C1 transmitted from the vehicle body right side transmitter 4 and the antenna code C2 transmitted from the vehicle body left side transmitter 5 are transmitted at different timings. Therefore, the electronic key 2 continuously receives the antenna codes C1 and C2 after the wake signal Swk. At this time, the reception code notification unit 18 reads the two antenna codes C1 and C2 received by the electronic key 2 and confirms that each radio wave transmitted from the vehicle body right part transmitter 4 and the vehicle body left part transmitter 5 is received. Check.

  When the electronic key 2 returns the ack signal Sack as a response to the wake signal Swk, the electronic key 2 receives the notification that the radio wave received by the electronic key 2 is the radio wave from the vehicle body right part transmitter 4 and the vehicle body left part transmitter 5. The code information Dac is added to the ACK signal Sack and transmitted. The reception code information Dac at this time is a bit signal of “011”, for example.

  When the vehicle 1 receives the ACK signal Sack, the use transmitter setting unit 19 reads the reception code information Dac given to the ACK signal Sack. Here, since it is assumed that the electronic key 2 is located in the area Ed, the transmitter setting unit 19 reads the received code information Dac of “011”. Therefore, the use transmitter setting unit 19 recognizes that the electronic key 2 exists in the area Ed, that is, in the vehicle.

  When the electronic key 2 is located in an area where the communication areas of the transmitters 4 to 6 overlap (that is, in the vehicle), in the subsequent smart communication after the ACK reception, communication is performed by any one of the transmitters 4 to 6 where the areas overlap. Can be continued. For this reason, when the electronic key 2 is located in an area (inside the vehicle) where the communication areas of the transmitters 4 to 6 overlap, a priority order that determines which transmitter 4 to 6 is used preferentially is set. . For this reason, when the electronic key 2 is located in a region (inside the vehicle) where the communication areas of the transmitters 4 to 6 overlap, the use transmitter setting unit 19 uses and transmits the transmitters 4 to 6 determined by this priority order. Set as a machine and perform subsequent smart communication.

  The verification ECU 7 recognizes from the received code information Dac of “011” that the electronic key 2 is in the area Ed, that is, the electronic key 2 is in the vehicle. Therefore, the collation ECU 7 recognizes that the smart collation in the vehicle is established if the smart collation with the electronic key 2 is established, and permits, for example, a power transition operation (engine start operation) by the engine switch 16.

According to the configuration of the present embodiment, the following effects can be obtained.
(1) During the polling operation, the verification ECU 7 assigns antenna codes C1 to C3 to the wake signal Swk and transmits the radio waves from the transmitters 4 to 6. When receiving the wake signal Swk, the electronic key 2 determines which transmitter 4 to 6 has received the radio wave by reading the antenna codes C1 to C3, and receives the reception code information Dac as a result of the determination. The ACK signal Sack, which is a response to the wake signal Swk, is added and transmitted. Based on the received code information Dac received together with the ACK signal Sack, the verification ECU 7 confirms which transmitter 4 to 6 of the plurality of transmitters 4 to 6 has established communication, and uses the transmitters 4 to 6 to be used. Set. Thereby, subsequent smart communication can be implemented only by the transmitter in which the electronic key 2 is located in the communication area among the plurality of transmitters 4 to 6. Therefore, communication can be performed without waste, and the communication time for smart verification can be shortened.

  (2) The antenna codes C1 to C3 are given to the wake signal Swk, and the reception code information Dac is given to the ack signal Sack which is a reception response of the wake signal Swk. Therefore, in the process of exchanging the wake signal Swk and the ack signal Sack between the vehicle 1 and the electronic key 2 performed at the initial stage of the smart verification, the transmitters 4 to 6 used in the subsequent smart communication are set. First, the optimum transmitters 4 to 6 can be set. Therefore, the effect of shortening the communication time of smart verification is increased.

  (3) The antenna codes C1 to C3 are transmitted from the transmitters 4 to 6 at different transmission timings. Therefore, since it is difficult for interference to occur in the antenna codes C1 to C3, the effect of securing the feasibility of smart communication is enhanced.

  (4) When the electronic key 2 is located in the overlapping areas Ed to Eg, a transmitter having a higher priority is set as a used transmitter in setting of a used transmitter. For this reason, when the electronic key 2 is located in the overlapping areas Ed to Eg, it is possible to specify the transmitter to be used, which further contributes to shortening of the communication time.

(Second Embodiment)
Next, 2nd Embodiment is described according to FIGS. This example is an example in which the vehicle 1 communicates with a plurality of electronic keys 2 at a time, and other basic configurations are the same as those in the first embodiment. Therefore, the same parts as those in the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and only different parts will be described.

  As shown in FIG. 7, the key control unit 13 of each of the electronic keys 2a and 2b is provided with a key identification information adding unit 20 that adds key identification information Dkn to the ACK signal Sack for transmission. The key identification information Dkn is information indicating which electronic key 2 is the transmission source of the ACK signal Sack, and is, for example, a key number registered in the electronic key 2. The key identification information Dkn is constructed from a bit signal of several bits, for example, similarly to the reception code information Dac.

  As shown in FIG. 8, each electronic key 2 transmits the reception code information Dac and the key identification information Dkn to the transmission timing so as not to interfere with the reception code information Dac and the key identification information Dkn transmitted from the other electronic keys 2. Shift and send. Incidentally, the transmission order of the electronic keys 2 is set in the order of increasing key numbers. In the case of this example, if the first electronic key 2a is a master key and the second electronic key 2b is a subkey, the received code information Dac and the key identification information Dkn are transmitted in the order of the first electronic key 2a → the second electronic key 2b. Is done.

Next, the operation of the electronic key system 3 of this example will be described with reference to FIG.
FIG. 9 assumes an example in which the first electronic key 2a is located in the area Ea and the second electronic key 2b is located in the area Ed. Therefore, in this case, the first electronic key 2a receives the wake signal Swk and the antenna code C1 transmitted from the vehicle body right part transmitter 4. The second electronic key 2b receives the wake signal Swk and the antenna code C1 transmitted from the vehicle body right part transmitter 4, and the wake signal Swk and the antenna code C2 transmitted from the vehicle body left part transmitter 5.

  The first electronic key 2a is activated by the wake signal Swk received from the vehicle body right part transmitter 4, and starts its operation. At this time, the reception code notification unit 18 of the first electronic key 2a reads the antenna code C1 and confirms that the radio wave transmitted from the vehicle body right part transmitter 4 has been received.

  Subsequently, when the first electronic key 2a transmits the ACK signal Sack as a response to the wake signal Swk, the reception code notifying unit 18 gives a bit signal of “001” as the reception code information Dac1 to the ACK signal Sack. Send. Further, the key identification information adding unit 20 also adds key identification information Dkn1 for notifying its own key number (for example, key number “1”) to the ack signal Sack. Therefore, the received code information Dac1 and the key identification information Dkn1 are given to the ack signal Sack of the first electronic key 2a and transmitted to the vehicle 1.

  The second electronic key 2b is activated by the wake signal Swk received from the vehicle body right part transmitter 4 (vehicle body left part transmitter 5), and starts its operation. At this time, the reception code notifying unit 18 of the second electronic key 2b reads the two antenna codes C1 and C2, and confirms that the radio waves transmitted from the vehicle body right part transmitter 4 and the vehicle body left part transmitter 5 are received. Check.

  Subsequently, when the second electronic key 2b transmits the ACK signal Sack as a response to the wake signal Swk, the reception code notification unit 18 adds a bit signal of “011” as the reception code information Dac2 to the ACK signal Sack. Send. Further, the key identification information adding unit 20 also adds key identification information Dkn2 for notifying its own key number (for example, key number “2”) to the ack signal Sack. Therefore, the reception code information Dac2 and the key identification information Dkn2 are given to the ACK signal Sack of the second electronic key 2b and transmitted to the vehicle 1.

  At this time, the second electronic key 2b transmits the reception code information Dac2 and the key identification information Dkn2 by delaying the transmission timing by a predetermined amount so as not to overlap with the reception code information Dac1 and the key identification information Dkn1 of the first electronic key 2a. Let Thereby, the vehicle receiver 12 can receive the reception code information Dac2 and the key identification information Dkn2 from the second electronic key 2b without interference.

  The use transmitter setting unit 19 confirms which key number of the electronic key 2 is located in which communication area based on the received reception code information Dac1, Dac2 and key identification information Dkn1, Dkn2. In the case of this example, the transmitter setting unit 19 confirms that the key number “1” takes the received code information “001” and the key number “2” takes the received code information “011”. It is recognized that the first electronic key 2a exists in the area Ea and the second electronic key 2b exists in the area Ed. Therefore, the use transmitter setting unit 19 sets the vehicle body right side transmitter 4 to be used for smart communication with the first electronic key 2a, and transmits the vehicle body right side for smart communication with the second electronic key 2b. Set to use machine 4.

  After confirming the receipt of the acknowledgment, the verification ECU 7 first executes smart communication with the first electronic key 2a. At this time, the verification ECU 7 transmits the verification code Sch with the key number specified as “1” from the vehicle body right side transmitter 4. Therefore, only the first electronic key 2a responds to the verification code Sch, and the first electronic key 2a transmits the response code Srs by UHF. The verification ECU 7 performs smart verification using the response code Srs received from the first electronic key 2a.

  When the verification ECU 7 confirms that smart verification with the first electronic key 2a is established, the verification ECU 7 subsequently executes smart communication with the second electronic key 2b. At this time, the verification ECU 7 transmits the verification code Sch with the key number “2” specified from the vehicle body right side transmitter 4. Therefore, only the second electronic key 2b responds to the verification code Sch, and the second electronic key 2b transmits the response code by UHF. The verification ECU 7 performs smart verification using the response code Srs received from the second electronic key 2b. When the verification ECU 7 confirms that the smart verification is established with the plurality of electronic keys 2a and 2b, the verification ECU 7 notifies the vehicle 1 with an indicator or the like.

According to the configuration of this embodiment, in addition to (1) to (4) described in the first embodiment, the following effects can be obtained.
(5) Even if there are a plurality of electronic keys 2a and 2b in the communication area of the transmitters 4 to 6, this can be determined. Therefore, the effect of improving the functionality of the electronic key system 3 is diversified.

Note that the embodiment is not limited to the configuration described so far, and may be modified as follows.
In the first embodiment, the transmission timing of radio waves (ACK signal Sack and received code information Dac) may be shifted depending on the difference between the master key and the sub key (that is, the key number). In this case, even if there are a plurality of electronic keys 2 in the communication area of the transmitters 4 to 6, radio waves from these electronic keys 2 can be received without interference. Therefore, the verification ECU 7 can recognize that there are a plurality of electronic keys 2 in the communication area.

  In each embodiment, authentication performed between the vehicle 1 and the electronic key 2 is not limited to vehicle ID verification, key number verification, challenge response authentication, electronic key ID verification, etc., and any of these may be used, Other authentications may be employed.

  In each embodiment, the antenna code C is not limited to being given to the wake signal Swk, but may be given to other signals. The reception code information Dac is not limited to being given to the ack signal Sack, but may be given to other signals.

  In each embodiment, the antenna code C may be information / data that can be notified of which radio wave is transmitted from any of the transmitters 4 to 6. The same applies to the received code information Dac.

In each embodiment, the antenna code C is not limited to being transmitted with the timing shifted, and may be the same timing, for example.
In each embodiment, the antenna code C is not limited to being given to the wake signal Swk and transmitted to the electronic key 2, but may be transmitted to the electronic key 2 as an independent single signal, for example. The same applies to the reception code information Dac given to the ACK signal Sack.

In each embodiment, the number and arrangement position of the transmitters 4 to 6 can be changed as appropriate.
In each embodiment, the electronic key system 3 is not limited to LF-UHF bidirectional communication. For example, LF-LF bidirectional communication may be used.

-In each embodiment, the frequency of the electronic key 2, the transmitters 4-6, and the vehicle receiver 12 can be changed into another frequency.
In each embodiment, the communication master is not limited to the vehicle 1 and can be changed to another device or device. In short, the electronic key system 3 of this example is applicable to devices and devices other than the vehicle 1.

Next, technical ideas that can be grasped from the above-described embodiment and other examples will be described below together with their effects.
(A) The key identification information according to any one of claims 1 to 4, which is provided in the electronic key and notifies the communication master of key identification information notifying which radio wave is transmitted from which electronic key. Notification means were provided. In this case, the transmitter to be used can be more suitably selected, which further contributes to shortening the communication time.

  (B) In any one of claims 1 to 4 and the technical idea (A), the reception information notification means transmits the radio wave reception information in a transmission order determined according to a key number of the electronic key. . In this case, even if a plurality of electronic keys exist in the communication area of the transmitter, it is possible to cope with this.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle as communication master, 2 (2a, 2b) ... Electronic key, 3 ... Electronic key system, 4-6 ... Transmitter, 17 ... Antenna code provision part as antenna information provision means, 18 ... Reception information notification means , Reception code notifying unit 19, used transmitter setting unit as transmitter setting means, C, C 1 to C 3, antenna code as antenna information, Dac, Dac 1, Dac 2, reception code information as radio wave reception information, Swk ... Wake signal, Sack ... ACK signal, E1-E3 ... Communication area, Ed-Eg ... Overlapping area.

Claims (4)

A plurality of transmitters provided in the communication master transmit a radio wave for confirming the presence of the electronic key, and the validity of the electronic key ID transmitted from the electronic key in response to the radio wave is determined from the transmitter. In the electronic key system that permits or executes the operation of the communication master if this ID verification is established while determining the position of the electronic key by a combination of responses of the electronic key to radio waves,
Antenna information providing means for providing antenna information to be provided to the communication master and notifying which radio wave is transmitted from each transmitter to the radio wave transmitted from each transmitter;
A reception information notifying unit that is provided in the electronic key, determines from which transmitter the radio wave is received based on the antenna information, and notifies the communication master of the radio wave reception information that is the determination result;
An electronic key system comprising: a transmitter setting unit that is provided in the communication master and sets a transmitter to be used for communication with the electronic key based on the radio wave reception information. The ID verification periodically transmits a wake signal from the communication master, and when the electronic key receives and activates the wake signal, transmits an ACK signal to the communication master, and the communication master receives the ACK signal. Then, the communication master and the electronic key are communications for starting authentication,
The antenna information giving means sends the antenna information to the electronic key from the communication master by giving the antenna information to the wake signal,
The reception information notification means transmits the radio wave reception information to the ACK signal and transmits it from the electronic key to the communication master,
The electronic key system according to claim 1, wherein the transmitter setting unit sets a transmitter to be used in subsequent communication based on the radio wave reception information. The electronic key system according to claim 2, wherein the wake signal is transmitted simultaneously from a plurality of the transmitters, and the antenna information is transmitted from each of the plurality of transmitters at different transmission timings. When the transmitter setting means confirms that the electronic key is located in an overlapping area where communication areas of the plurality of transmitters overlap with each other, a preset priority order among the plurality of transmitters to which communication is established is established. The electronic key system according to any one of claims 1 to 3, wherein a transmitter to be used is set along the line.