JP2009035970A - Smart keyless entry system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent disturbing radio communications in other smart keyless system. <P>SOLUTION: The smart keyless entry system is composed of an in-vehicle machine mounted in the vehicle and a portable machine a driver carries while the portable machine, when receiving a signal from the in-vehicle machine, transmits a signal responding to the in-vehicle machine. On receiving the signal from the portable machine, the in-vehicle machine controls an in-vehicle control equipment. The invention includes an other-vehicle signal detection means for detecting a signal from the other vehicles transmitted by an in-vehicle machine 100B of the other smart keyless system and also a transmission-timing changing means, in case the other-vehicle signal detection means detects the signal from the other in-vehicle machine 100B when the portable machine 200A transmits the signal to an in-vehicle machine 100A, for changing a transmission timing of the signal different from the transmission timing of the signal responding to the signal from the other in-vehicle machine 100B transmitted from the portable machine 200B of the other smart keyless entry system receiving the signal from the other in-vehicle machine 100B. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a smart keyless entry system that locks / unlocks a vehicle door or permits engine start without using a key, and belongs to the technical field of wireless communication in the smart keyless entry system.

  2. Description of the Related Art Conventionally, there is a control system that locks or unlocks a door of a vehicle based on a signal from a portable device carried by an occupant, or permits an engine to start (see, for example, Patent Document 1). In this system, it is possible to perform the same operation as a conventional key only by carrying the portable device without performing a manual operation like a conventional key. This system is therefore called a smart keyless entry system.

  The smart keyless entry system is composed of an in-vehicle device mounted on a vehicle and a portable device carried by an occupant, and by performing wireless communication between them, the in-vehicle device locks or unlocks the door of the vehicle, Or control which permits starting of an engine is performed. For example, when an occupant carrying a portable device gets on, the engine is permitted to start.

JP 2006-104664 A

  However, wireless communication between a portable device of a certain smart keyless entry system (hereinafter referred to as “own system”) and an in-vehicle device is performed by another smart keyless entry system (hereinafter referred to as “other system”). Wireless communication between the portable device and the vehicle-mounted device may be disturbed by radio wave interference, or may interfere with each other by causing radio wave interference with each other. For example, radio wave interference may occur when the distance between vehicles equipped with the same configuration smart keyless entry system is short.

  Therefore, an object of the present invention is to provide a smart keyless entry system that can suppress the occurrence of radio wave interference that may interfere with communication between a portable device and an in-vehicle device of another smart keyless entry system.

In order to solve the above-mentioned problem, the invention according to claim 1 of the present application includes an in-vehicle device mounted on a vehicle and a portable device carried by an occupant, and the portable device receives a signal from the in-vehicle device. Then, a signal that responds to the in-vehicle device is transmitted, the in-vehicle device is a smart keyless entry system that receives the signal from the portable device and controls the in-vehicle control device,
Other vehicle-mounted device signal detection means for detecting a signal of another vehicle-mounted device transmitted from the vehicle-mounted device of another smart keyless entry system,
When the other vehicle-mounted device signal detection means detects the signal of the other vehicle-mounted device when transmitting a signal from the portable device to the vehicle-mounted device, the transmission timing of the signal is set to the signal of the other vehicle-mounted device. Transmission timing changing means for changing the signal to be different from the transmission timing of the signal responding to the signal of the other in-vehicle device transmitted from the portable device of another received smart keyless entry system.

The invention according to claim 2 is the smart keyless entry system according to claim 1,
The in-vehicle device is configured to transmit a signal at a repetition period with a certain interval,
The transmission timing changing unit is configured to change a transmission timing of a signal transmitted from the portable device to the in-vehicle device based on a repetition period of a signal of the other in-vehicle device detected by the other in-vehicle device signal detecting unit. To do.

Furthermore, the invention according to claim 3 is the smart keyless entry system according to claim 1,
The portable device is configured to transmit a signal for a predetermined time when a predetermined signal is received from the in-vehicle device,
The transmission timing changing means transmits a signal from the portable device to the in-vehicle device after the predetermined time has elapsed since the other in-vehicle device signal detecting means detected the predetermined signal of the other in-vehicle device. It is characterized by the transmission timing to be performed.

  According to the first aspect of the present invention, when a signal is transmitted from the portable device to the in-vehicle device in the own system, the other in-vehicle device signal detection means detects the signal from the in-vehicle device of the other system (other in-vehicle device signal). In this case, the transmission timing of the signal to be transmitted is changed to be different from the timing at which the portable device of the other system transmits a signal that responds to the other vehicle-mounted device signal. This is because when the other vehicle-mounted device signal detecting means detects the other vehicle-mounted device signal (or after that), the portable device of the other system transmits a signal that responds to the other vehicle-mounted device signal to the vehicle-mounted device of the other system. If the portable device of the local system transmits a signal at this time, the signal transmission timing of the portable device of the local system overlaps the signal transmission timing of the portable device of the other system, resulting in radio wave interference. This is because there is a possibility. By suppressing the occurrence of this radio wave interference, the transmission from the portable device to the in-vehicle device in both the own system and the other system is executed without being disturbed.

  Note that “timing” here does not mean the moment (a point on the time axis) but a period (a distance between two points on the time axis). Therefore, the transmission timing refers to a period during which a signal is transmitted, and that the transmission timing is different means that there is no period overlapping with other transmission timings.

  According to the second aspect of the present invention, when another vehicle-mounted device signal transmitted at a fixed interval is detected, the vehicle-mounted device of the smart keyless entry system has a fixed interval. It is configured to repeatedly transmit a signal at an open repetition period, and repeatedly transmits a signal to which the portable device responds every time the signal is received.), Another on-vehicle device signal transmitted from the on-vehicle device of another system Is changed so that the transmission timing of the signal transmitted from the portable device of the own system is different from the transmission timing of the signal from the portable device of the other system. That is, based on the repetition period, the signal of the portable device of the own system is transmitted before the signal transmission of the portable device of the other system is finished and the transmission of the next signal is started. As a result, radio wave interference is suppressed, and transmission from the portable device to the in-vehicle device in both the own system and the other system is executed without being disturbed.

  Further, according to the third aspect of the present invention, when a predetermined signal of another vehicle-mounted device is detected (assuming that the portable device of the smart keyless entry system receives the predetermined signal from the vehicle-mounted device as a precondition, The transmission timing of the signal transmitted from the portable device of its own system is set after the predetermined time or more has elapsed since the detection of the predetermined signal of the other vehicle-mounted device. Thereby, after the portable device of the other system finishes transmitting the signal for a certain time, the signal of the portable device of its own system is transmitted. As a result, radio wave interference is suppressed, and transmission from the portable device to the in-vehicle device in both the own system and the other system is executed without being disturbed.

  First, the outline of the smart keyless entry system according to the present invention will be described, and subsequently, wireless communication between the portable device and the in-vehicle device in another smart keyless entry system, which is a feature of the present invention, will be obstructed by radio wave interference. The details of the characteristic part of the system to avoid this will be described.

  FIG. 1 shows a vehicle equipped with a smart keyless entry system according to an embodiment of the present invention and a portable device of the system. FIG. 2 shows the configuration of the smart keyless entry system.

  As shown in FIG. 2, the smart keyless entry system includes an in-vehicle device 100 mounted on the vehicle 10 shown in FIG. 1 and a portable device 200 carried by a passenger.

  The in-vehicle device 100 includes a plurality of LF transmission antennas 102a to 102e for transmitting signals to the portable device 200, a UHF receiver 104 for receiving signals from the portable device 200, and a plurality of LF transmission antennas 102a to 102e. And a control device 106 that controls a control device mounted on the vehicle 10 based on a signal received by the UHF receiver 104.

  Each of the plurality of LF transmission antennas 102a to 102e is disposed at a predetermined position of the vehicle 10 as shown in FIG. The LF transmitting antenna 102a is located in the front door 14 on the passenger seat 12, the door 102b is located in the rear door 16, 102c is located in the door 18 on the driver's seat, 102d is located in front of the passenger seat 12, and 102e is located in the passenger compartment. It is disposed under the central rear seat 20.

  Each of the plurality of LF transmitting antennas 102a to 102e is controlled by the control device 106 to form an LF band magnetic field corresponding to a signal transmitted around it, and as shown in FIG. It is configured to perform communication (magnetic field communication) from the antenna to the portable device by detecting the LF band magnetic field formed in the detection circuit and receiving the above-described signal (magnetic field signal) based on the detected magnetic field. ing. Since the communication uses the magnetic field of the LF band, the transmission range (communication possible range) of the LF transmission antennas 102a to 102e is small as shown in FIG. The LF transmission antenna 102a has a transmission range A1 on the outside of the passenger door 14; 102b has a transmission range A2 on the outside of the rear door 16; 102c has a transmission range A3 on the outside of the driver side door 18; Is the transmission range A4, and 102e is the transmission range A5 on the rear side of the passenger compartment. It should be noted that these transmission ranges naturally change to be larger or smaller depending on the circumstances such as the environment around the vehicle 10.

  Returning to FIG. 1, the UHF receiver 104 is disposed in front of the driver's seat. Further, as shown in FIG. 2, the UHF receiver 104 receives a UHF band radio signal from a UHF transmission antenna of the portable device 200 to be described later, and sends a signal corresponding to the received radio signal to the control device 106. It is configured to output to.

  The control device 106 is configured to control in-vehicle control devices such as a door lock actuator 50, an engine control unit (ECU) 52, and an alarm device 54 mounted on the vehicle 10 based on a signal from the UHF receiver 104. Has been. The door lock actuator 50 is provided in each of the passenger seat side door 14, the rear door 16, the driver seat side door 18, and the rear seat door, and locks or unlocks these doors. The ECU 52 is for controlling the engine, and the control device 106 is configured to allow the ECU 52 to start the engine. The engine is started by turning on an ignition switch (not shown) by the occupant after the control device 106 allows the ECU 52 to start the engine. Further, the alarm device 54 warns when the portable device 200 is taken out of the vehicle interior during driving. Details of the control executed by the control device 106 for these control devices will be described later.

  On the other hand, the portable device 200 has a card size that is portable as shown in FIG. 1, and receives a signal from any of the plurality of LF transmission antennas 102a to 102e of the in-vehicle device 100 as shown in FIG. A magnetic field detection circuit 202 for receiving, a lock switch 204 a for locking a door by an occupant outside the vehicle, an unlock switch 204 b for unlocking the door, and the UHF receiver 104 of the in-vehicle device 100 via the UHF transmission antenna 206. It has a UHF transmission circuit 208 for transmitting a radio signal in the UHF band, and a control device 210 that controls the UHF transmission circuit 208 to transmit various signals.

  When the portable device 200 exists in the transmission range of any of the plurality of LF transmission antennas 102a to 102e of the in-vehicle device 100 and the LF transmission antenna in the transmission range outputs a magnetic field signal, the magnetic field detection circuit 202 outputs the magnetic field. It is configured to receive a signal. Further, the control unit 210 is configured to output a signal corresponding to the received magnetic field signal.

  As shown in FIG. 1, the lock switch 204 a and the unlock switch 204 b are button-like operation switches that the occupant presses, and are provided in the portable device 200. When the occupant performs an operation of pressing, the lock switch 204a and the unlock switch 204b are configured to output a signal indicating that the operation has been performed to the control device 210.

  The UHF transmission circuit 208 is configured to be able to transmit various signals via the UHF transmission antenna 206 under the control of the control device 210. Note that the transmission from the in-vehicle device 100 to the portable device 200 is a magnetic field signal, whereas the reason for using a radio signal in the UHF band for the transmission from the portable device 200 to the in-vehicle device 100 is the UHF built in the portable device 200. This is because the transmission antenna 206 can be reduced in size, that is, the portable device 200 can be reduced in a card shape.

  The control device 210 is configured to control the UHF transmission circuit 208 based on signals from the magnetic field detection circuit 202, the lock switch 204a, and the unlock switch 204b. Details of the control will be described later.

  From here, the details of each component of the smart keyless entry system will be described while explaining the operation of the smart keyless entry system, that is, the operations of the in-vehicle device 100 and the portable device 200.

  First, when an occupant carrying the portable device 200 operates the lock switch 204a or the unlock switch 204b to unlock the door to get on the vehicle 10 or to get off and lock the door (that is, outside the vehicle compartment) The control device 210 of the portable device 200 causes the UHF transmission circuit 208 to transmit a signal.

  When the UHF receiver 104 of the in-vehicle device 100 receives the lock signal for locking the door or the unlock signal for unlocking, the control device 106 of the in-vehicle device 100 receives the request signal from the plurality of LF transmission antennas 102a to 102e. Send through each.

  At this time, when the portable device 200 exists in any one of the transmission ranges of the LF transmission antennas 102a to 102e, the magnetic field detection circuit 202 of the portable device 200 receives a request signal from the antenna in the transmission range where the portable device 200 exists. .

  Then, the portable device 200 transmits an ID signal (a signal indicating the ID of the portable device 200) by controlling the UHF transmission circuit 208.

  When the UHF receiver 104 of the in-vehicle device 100 receives the ID signal, the control device 106 of the in-vehicle device 100 performs ID authentication based on the received ID signal. When the ID authentication is established, the control device 106 controls the lock actuator 50 to unlock or lock the vehicle door.

  On the other hand, when the ID authentication is not established or when the UHF receiver 104 cannot receive the ID signal within a predetermined time after transmitting the request signal, the control device 106 locks or unlocks the door. Do not execute control (time out).

  Next, when the occupant gets on the vehicle 10 (for example, when the door opening / closing sensor detects that the door is opened and closed again after the door is unlocked by the portable device 200), the control device of the in-vehicle device 100 106 confirms that the portable device 200 exists in the vehicle interior in order to allow the ECU 52 to start the engine. That is, it is confirmed whether or not an occupant carrying the portable device 200 is on board.

  Specifically, the control device 106 of the in-vehicle device 100 transmits a request signal for confirming that the portable device 200 exists in the passenger compartment from the transmission antennas 102d and 102e for the passenger compartment, and receives the request signal. The portable device 200 transmits an ID signal, and the in-vehicle device 100 confirms that the portable device 200 exists in the vehicle interior when ID authentication is established based on the received ID signal.

  When it is confirmed that the portable device 200 exists in the vehicle interior of the vehicle 10, the control device 106 of the in-vehicle device 100 permits the ECU 52 to start the engine. In this state, when an occupant turns on an ignition switch (not shown), the ECU 52 starts the engine.

  In addition, confirmation that the portable device 200 is present in the vehicle interior of the vehicle 10 is performed after it is confirmed that the portable device 200 exists once in the vehicle interior until the door is opened (the door is opened and the portable device 200 is carried). Until the occupant gets off). This is because, for example, there is a possibility that the vehicle 10 stops and the glass window of the door is opened despite the driving, and the portable device 200 is taken out of the passenger compartment together with the luggage through the window glass. . If the portable device 200 is taken out of the passenger compartment, the engine may not be restarted when returning from the stopped state.

  In order to deal with this, until it is confirmed that the portable device 200 exists in the vehicle interior and the door is opened, the control device 106 of the in-vehicle device 100 periodically confirms that the portable device 200 exists in the vehicle interior. If it is not confirmed, the alarm device 54 is controlled to give an alarm.

  Hereafter, the details of the characteristic part of the system for preventing radio communication between the portable device and the vehicle-mounted device in another smart keyless entry system, which is a characteristic part of the present invention, from being caused by radio wave interference will be described.

In addition, the other smart keyless entry system said by this embodiment means the system which consists of the same vehicle equipment and portable machine (strictly speaking, only ID differs), and is mounted in the other vehicle.

  First, a situation where radio wave interference can occur will be described. As shown in FIG. 4, the situation where radio wave interference can occur is that the distance between the vehicle 10A equipped with the smart keyless entry system having the same configuration and the vehicle 10B is short and the mobile device 200A for the vehicle 10A This is a situation where the timing at which the radio signal (dotted line) is transmitted and the timing at which the radio signal is transmitted from the portable device 200B for the vehicle B overlap (situation at timing T0). When the transmission timings of the radio signals of the portable devices 200A and 200B overlap, radio wave interference occurs and transmission from the portable device 200A to the in-vehicle device 100A and / or transmission from the portable device 200B to the in-vehicle device 100B is not performed well. there is a possibility.

  Thus, when there is a possibility that the transmission timing of the radio signal of the portable device 200A for the vehicle 10A and the transmission timing of the radio signal of the portable device 200B for the vehicle 10B may overlap, the portable device for one vehicle The smart keyless entry system is configured such that the radio signal is transmitted at a timing different from the transmission timing at which the vehicle portable device transmits the radio signal.

  This will be specifically described. Since the portable device 200 of the smart keyless entry system has the magnetic field detection circuit 202 as shown in FIG. 2, it also detects the magnetic field formed around the LF transmission antenna of the in-vehicle device of the other smart keyless entry system. It is also possible to receive a magnetic field signal from the in-vehicle device of the system (the magnetic field detection circuit 202 functions as other on-vehicle device signal detecting means described in the claims).

  For example, as shown in FIG. 5, the portable device 200A for the vehicle 10A can receive the magnetic field signal (magnetic field area B) transmitted from the vehicle-mounted device 100B for the vehicle 10B (the LF transmission antenna of the vehicle-mounted device 100B). . Conversely, the magnetic field signal (magnetic field area A) transmitted from the vehicle-mounted device 100A for the vehicle 10A (the LF transmission antenna of the vehicle-mounted device 100A) can be received by the portable device 200B for the vehicle B.

  In addition, since the portable device 200 can also receive a magnetic field signal from an in-vehicle device of another smart keyless entry system as described above, the received magnetic field signal forms an in-vehicle device (an in-vehicle device that forms a pair with the received portable device). Device) or an in-vehicle device of another system (an in-vehicle device that forms a pair with a different portable device from the received portable device).

  Taking FIG. 5 as an example, the portable device 200A determines whether the received magnetic field signal is transmitted by the in-vehicle device 100A (in-vehicle device of its own system) or the in-vehicle device 100B (in-vehicle device of another system). .

  In order to make the determination possible, for example, the in-vehicle device transmits a magnetic field signal indicating the ID of the in-vehicle device together with a magnetic field signal indicating a request signal and the received control device of the portable device receives the ID of the in-vehicle device. ID authentication is performed based on a magnetic field signal indicating. When ID authentication is established, the control device of the portable device determines that the signal is a magnetic field signal from the in-vehicle device of its own system. On the other hand, when the authentication is not established, the magnetic field signal from the in-vehicle device of another system is determined. To be judged.

  Alternatively, if the magnetic field signal transmitted from the in-vehicle device to the portable device for each smart keyless entry system is set in advance to use a different magnetic field signal, and the portable device receives a magnetic field signal that matches the setting, It may be determined that the signal is a magnetic field signal from a machine, and when a magnetic field signal different from the setting is received, it is determined that the signal is a magnetic field signal from an in-vehicle device of another system.

  As described above (as shown in FIG. 5), when the portable device 200A of the own system receives the magnetic field signal from the in-vehicle device 100B of the other system, the portable device 200A is at a distance close to the in-vehicle device 100B. It means that the vehicle 10A equipped with the own system and the vehicle 10B equipped with another system are at a short distance.

  Further, as shown in FIG. 5, when the portable device 200A of the own system receives a magnetic field signal (for example, a magnetic field signal indicating a request signal) from the in-vehicle device 100B of the other system, the portable device 200B of the other system also receives the magnetic field. This means that there is a possibility that the portable device 200B receives a signal and then transmits a radio signal (for example, a radio signal indicating an ID signal) in response to the magnetic field signal.

  Therefore, when the portable device 200A transmits a radio signal (for example, when the lock switch 204a is pushed by an occupant and transmits a lock signal for locking the door), the control device of the portable device 200A of the system is another system. If the mobile device 200B of the other system transmits a radio signal after that, the transmission timing of the radio signals of the mobile devices 200A and 200B may overlap. The transmission timing of the radio signal is changed after the portable device 200B transmits the radio signal (the control device functions as a transmission timing changing means described in the claims).

  Specifically, in the example shown in FIG. 5, when the portable device 200A receives the magnetic field signal from the in-vehicle device 100B at the timing T1 when transmitting the radio wave signal, the portable device 200A has a timing T2 following the timing T1. Since the portable device 200B may transmit a radio signal, the portable device 200B is configured to transmit the radio signal at a timing T3 after the timing T2 at which the portable device 200B transmits the radio signal.

  Even if the in-vehicle device 100B of the other system transmits a magnetic field signal, the portable device 200B of the other system may not receive the magnetic field signal and may not transmit a radio signal (for example, the in-vehicle device 100B and the portable device). 200B is separated.) However, the portable device 200A of the own system that has received the magnetic field signal from the in-vehicle device 100B of the other system has failed to receive the magnetic field signal by the portable device 200B of the other system, that is, the portable device 200B has received the radio signal. Since it cannot be detected that transmission is not performed, when a magnetic field signal is received from the in-vehicle device 100B of another system, it is always assumed that the portable device 200B of the other system transmits a radio signal thereafter.

  Further, as described above, the portable device 200A of its own system indirectly transmits the radio signal transmission timing T2 of the portable device 200B of the other system based on the reception timing T1 of the magnetic field signal from the in-vehicle device 100B of the other system. And the radio signal is transmitted at a timing T3 different from the detected timing T2. This is possible because, in the specifications of the smart keyless entry system, the portable device is configured to transmit a radio signal in response to a magnetic field signal from the in-vehicle device. For example, as described above, the portable device returns an ID signal in response to a request signal from the in-vehicle device. However, the lock signal / unlock signal transmitted when the lock switch 204a / unlock switch 204b of the portable device 200 is pressed is not limited to this.

  Further, as described above, the portable device 200A of the own system can transmit the radio signal at the timing T3 after the portable device 200B of the other system transmits the radio signal, except that the own system and the other system exclude the ID. This is because the transmission signal transmission completion time of the portable device 200B of the other system is known because they are the same.

  For example, a smart keyless entry system is configured such that a portable device that has received a magnetic field signal indicating a request signal transmits a radio wave signal indicating an ID signal to be transmitted in response for a predetermined time (request signal). Corresponds to the predetermined signal described in the claims, and the ID signal corresponds to the signal for a certain period of time).

  In the example shown in FIG. 5, the timing at which the portable device 200A of the own system receives the request signal from the in-vehicle device 100B of the other system is before and after the timing at which the portable device 200B of the other system receives the request signal ( This is because the distance between the portable device 200A and the in-vehicle device 100B of 200B is different.) Therefore, if the time after the elapse of a certain time (ID signal transmission time) or longer after the portable device 200A receives the request signal from the in-vehicle device 100B is set as the transmission timing of the radio signal of the portable device 200A, the request The transmission timing of the ID signal of the portable device 200B of the other system that has received the signal is different from the transmission timing of the portable device 200A, and the transmission of the radio signal of the portable device 200B does not interfere with the transmission of the radio signal of the portable device 200B.

  In consideration of the above, the control device 210 of the portable device 200 performs communication without interfering with the communication between the portable device of the other smart keyless entry system and the in-vehicle device, that is, the communication while suppressing the occurrence of radio wave interference. An example of the control flow will be described with reference to the flow shown in FIG.

  First, as shown in FIG. 6, the control starts when a request for transmitting a radio signal from the portable device 200 to the in-vehicle device 100 is confirmed in S510. The request for transmission of the radio signal is, for example, when the lock switch 204a / unlock switch 204b of the portable device 200 is pushed by the occupant to transmit a radio signal indicating the lock signal / unlock signal, or a request signal from the in-vehicle device 100 This is confirmed when a radio signal indicating an ID signal is transmitted.

  Next, in S520, the control device 210 of the portable device 200 determines whether or not the magnetic field detection circuit 202 has detected the magnetic field formed by the LF transmission antenna of the in-vehicle device of another smart keyless entry system, that is, another in-vehicle device. It is determined whether or not a magnetic field signal is received from. If a magnetic field signal is received from another in-vehicle device, the process proceeds to S530. Then, after waiting for a predetermined time, the process returns to S520.

  On the other hand, if it is determined in S520 that a magnetic field signal from another vehicle-mounted device has not been received, in S540, the portable device 200 transmits the radio signal requested for transmission confirmed in S510.

  Although the present invention has been described with reference to the above-described embodiment, the present invention is not limited to this.

  For example, when a magnetic field signal is transmitted from a vehicle-mounted device of another system at a repetition cycle with a certain interval, and a radio signal that is transmitted by a portable device of another system that has received the magnetic field signal is transmitted at the repetition cycle ( For example, when a request signal is periodically transmitted from an in-vehicle device and the portable device transmits an ID signal every time the request signal is received), the portable device of its own system must transmit a radio signal. There is a case.

  In this case, the transmission timing of the radio signal of the portable device of the own system that can suppress the occurrence of radio wave interference is from the end of signal transmission of the portable device of the other system to the start of transmission of the next signal. This transmission timing can be calculated based on the repetition period of the magnetic field signal transmitted from the in-vehicle device of the other system. Specifically, the control device of the portable device synchronizes with the repetition period of the received magnetic field signal from the in-vehicle device of the other system, and calculates a transmission timing different from the transmission timing of the radio signal of the portable device of the other system. The radio signal is transmitted at the calculated transmission timing.

Of course, this is based on the premise that the vehicle-mounted device is configured to repeatedly transmit signals at a predetermined interval when repeatedly transmitting signals.

  Control that communicates without interfering with communication that is repeatedly performed with a certain interval between the portable device of the other smart keyless entry system and the vehicle-mounted device in consideration of this An example of a control flow for communication while suppressing the occurrence of radio wave interference will be described with reference to the flow shown in FIG.

  First, as shown in FIG. 7, the control starts when a request for transmitting a radio signal from the portable device to the vehicle-mounted device is confirmed in S610.

  Next, in S620, the control device of the portable device determines whether the magnetic field detection circuit detects the magnetic field formed by the LF transmission antenna of the in-vehicle device of another smart keyless entry system, that is, the magnetic field from the other in-vehicle device. It is determined whether a signal is received. If a magnetic field signal is received from another in-vehicle device, the process proceeds to S630. Otherwise, the process proceeds to S660, and the portable device transmits the radio signal requested for transmission confirmed in S610.

  Subsequently, in S630, the control device of the portable device synchronizes with the repetition cycle of the received magnetic field signal.

  In S640, the control device of the portable device calculates the transmission timing for the radio signal requested to be transmitted in S610, which is different from the transmission timing of the radio signal of the portable device of the other system, based on the repetition period synchronized in S630. To do.

  In S650, the control device of the portable device transmits the radio signal requested to be transmitted in S610 based on the transmission timing calculated in S640.

  In the above-described embodiment, as shown in FIG. 5, when the portable device 200 </ b> A receives a magnetic field signal of the in-vehicle device 100 </ b> B of another system when transmitting the radio signal, the radio signal is transmitted. The timing is changed after the portable device 200B of another system that has received the magnetic field signal from the in-vehicle device 200B transmits the radio signal, but the timing is not limited to this, and may be changed before.

  In this case, the portable device of the smart keyless entry system needs to be configured to transmit a radio wave signal that responds after a certain time after receiving the magnetic core from the in-vehicle device. In the example of FIG. 5, the portable device 200B of the other system that has received the magnetic field signal of the in-vehicle device 100B of the other system waits for a certain time for transmission of the responding radio signal, and then precedes the portable device 200A of its own system. A radio signal is transmitted.

  Furthermore, in the above-described embodiment, the occurrence of radio wave interference between the same smart keyless systems is suppressed only by different IDs, but the present invention is not limited to this.

  That is, if the transmission of the radio signal from the portable device is almost done to respond to the signal from the in-vehicle device, and the upper limit of the transmission time of the radio signal is predetermined, it is not the same under this condition It is possible to suppress the occurrence of radio wave interference between smart keyless entry systems.

  For example, when a portable device receives a signal from an in-vehicle device of another system when transmitting a radio signal, the radio signal is transmitted after a time equal to or longer than a predetermined upper limit transmission time has elapsed since reception. A smart keyless entry system may be configured.

  As described above, according to the present invention, the portable device and the vehicle-mounted device can perform wireless communication without interfering with the wireless communication between the portable device of the other smart keyless entry system and the vehicle-mounted device. Therefore, it may be suitably used in the field of the vehicle manufacturing industry equipped with the smart keyless entry system.

It is a figure showing a vehicle carrying a smart keyless entry system according to an embodiment of the present invention and a portable device of the system. It is a figure which shows the structure of the smart keyless entry system which concerns on one Embodiment of this invention. It is a figure which shows the transmission range of several LF transmission antenna with which the vehicle equipment of a smart keyless entry system is provided. It is a figure for demonstrating the condition where radio wave interference may occur in two smart keyless entry systems. It is a figure for demonstrating the method to suppress generation | occurrence | production of the radio wave interference shown in FIG. It is a figure which shows an example of the control flow of the control apparatus of the portable device which suppresses generation | occurrence | production of radio wave interference. It is a figure which shows another example of the control flow of the control apparatus of the portable device which suppresses generation | occurrence | production of radio wave interference.

Explanation of symbols

100A In-vehicle device of own smart keyless entry system 100B In-vehicle device of other smart keyless entry system 200A Portable device of own smart keyless entry system 200B Portable device of other smart keyless entry system

Claims (3)

It consists of an in-vehicle device mounted on a vehicle and a portable device carried by a passenger, and when the portable device receives a signal from the in-vehicle device, it transmits a signal responding to the in-vehicle device, and the in-vehicle device is transmitted from the portable device. Is a smart keyless entry system that controls the in-vehicle control device by receiving the signal of
Other vehicle-mounted device signal detection means for detecting a signal of another vehicle-mounted device transmitted from the vehicle-mounted device of another smart keyless entry system,
When the other vehicle-mounted device signal detection means detects the signal of the other vehicle-mounted device when transmitting a signal from the portable device to the vehicle-mounted device, the transmission timing of the signal is set to the signal of the other vehicle-mounted device. Smart keyless, comprising: transmission timing changing means for changing the signal to be different from the transmission timing of the signal responding to the signal of the other in-vehicle device transmitted from the portable device of the other smart keyless entry system received Entry system. In the smart keyless entry system according to claim 1,
The in-vehicle device is configured to transmit a signal at a repetition period with a certain interval,
The transmission timing changing unit is configured to change a transmission timing of a signal transmitted from the portable device to the in-vehicle device based on a repetition period of a signal of the other in-vehicle device detected by the other in-vehicle device signal detecting unit. Smart keyless entry system. In the smart keyless entry system according to claim 1,
The portable device is configured to transmit a signal for a predetermined time when a predetermined signal is received from the in-vehicle device,
The transmission timing changing means transmits a signal from the portable device to the in-vehicle device after the predetermined time has elapsed since the other in-vehicle device signal detecting means detected the predetermined signal of the other in-vehicle device. A smart keyless entry system characterized in that the transmission timing is determined.

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