JP2012184544A - Communication system for vehicle equipment remote control and communication method for vehicle equipment remote control - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a communication disabled area due to multipath interference without using a plurality of antennas.SOLUTION: In an on-vehicle device 10 which performs radio communication with a portable machine, when a door detection section 11 detects an open state of a door of a vehicle, a determination section 12 directs a transmission section 13 to periodically transmit an inquiry signal until receiving a response signal from the portable machine. Thus, the present invention can perform a plurality of trial communication with the mobile portable machine at difference positions and timing without using a plurality of antennas.

Description

  The present invention relates to a communication system for remote control of vehicle equipment and a method thereof for performing remote control of vehicle equipment by performing wireless communication between an on-vehicle device and a portable device.

  The conventional remote control system for vehicle equipment operates in addition to a remote operation function (so-called keyless entry function) for operating / operating the operation unit of the portable device to lock / unlock the door of the vehicle, and locking without operating this operation unit. / Equipped with a smart entry function for unlocking. In the smart entry function, the portable device automatically returns a response code signal in response to the question signal from the on-vehicle device, and the on-vehicle device collates this code and locks / unlocks the door according to the collation result. .

  For example, Patent Document 1 proposes a keyless entry system including a portable wireless device and an in-vehicle wireless device. In this system, the portable wireless device includes first receiving means for receiving a call signal and first transmission means for transmitting a response signal when the call signal is received by the first receiving means. The other in-vehicle wireless device includes a second transmission unit that transmits a call signal at a predetermined time interval, a second reception unit that receives a response signal from the first transmission unit, and the second reception unit. And a control means for outputting a signal for unlocking the door of the vehicle when the response signal is received, and outputting a signal for locking the door of the vehicle after a predetermined time if no response signal is received.

In such a conventional vehicle equipment remote control system, since the portable device and the vehicle-mounted device perform code collation by communication, there may be a region where communication is impossible due to the influence of multipath interference. For this reason, when the portable device is in an area where communication is not possible, there is a problem that code verification by communication cannot be performed and the vehicle device cannot be controlled.
Therefore, in Patent Document 2, it is proposed that a plurality of antennas are provided in each of the portable device and the vehicle-mounted device, and a communication impossible area is reduced by securing communication paths between the plurality of antennas.

Japanese Patent Laid-Open No. 5-106376 ([0005] paragraph, FIG. 1) JP 2007-51471 A ([0046] paragraph, FIG. 2)

  As in Patent Document 2, the configuration using a plurality of antennas to reduce the incommunicable region has a problem that the cost increases. Moreover, there also existed a subject that a portable apparatus will become large by mounting a some antenna in a portable apparatus.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to reduce an incommunicable region due to multipath interference without using a plurality of antennas.

  A communication system for vehicle equipment remote control according to the present invention includes an in-vehicle device and a portable device. The on-vehicle device includes a door detection unit that detects an open / closed state of a door of the vehicle, an antenna, and a portable device. And a first determination unit that controls the first transmission / reception unit to transmit and receive signals. The first determination unit includes a door detection unit that opens the door. When a state is detected, a question signal is periodically transmitted from the first transmission / reception unit until a response signal is received from the portable device, and the portable device has an antenna and performs wireless communication with the vehicle-mounted device A second transmission / reception unit; and a second determination unit that controls the second transmission / reception unit to transmit and receive signals. The second determination unit includes a second transmission / reception unit that receives an interrogation signal from the vehicle-mounted device. If it is received, a response signal for remotely controlling the vehicle equipment to perform a predetermined operation is sent. It is obtained so as to transmit from the transceiver.

  In the vehicle device remote control communication method according to the present invention, when the vehicle-mounted device detects the open state of the vehicle door, a question signal transmission step of periodically transmitting a question signal until receiving a response signal from the portable device. And a response signal transmitting step of transmitting a response signal for remotely controlling the vehicle device to perform a predetermined operation when the portable device receives the question signal transmitted from the vehicle-mounted device in the question signal transmitting step. It is what I did.

  According to the present invention, the open state of the door is detected in the vehicle-mounted device, and the question signal is periodically transmitted until the response signal from the portable device is received. An area where communication is impossible by estimating the timing when the portable device moves and trying multiple times of wireless communication while the portable device is moving, so that multiple communication attempts can be made at different positions and timings without using multiple antennas. Can be reduced. As a result, reliable code verification around the vehicle can be realized.

It is a block diagram which shows the structure of the onboard equipment which concerns on Embodiment 1 of this invention. It is a block diagram which shows the structure of the portable device which concerns on Embodiment 1 of this invention. It is a block diagram which shows the internal structure of the electric power control part with which onboard equipment is provided. It is a block diagram which shows the internal structure of the starting circuit part with which a portable device is provided. 4 is a flowchart illustrating an operation of a determination unit included in the vehicle-mounted device according to Embodiment 1. 6 is a flowchart illustrating an operation of a determination unit included in the portable device according to the first embodiment. It is a figure for demonstrating the communication method for the smart entry function implementation | achievement by the onboard equipment and portable device which concern on Embodiment 1. FIG. It is a block diagram which shows the internal structure of the receiving part with which the portable device which concerns on Embodiment 2 of this invention is provided. It is a flowchart which shows operation | movement of the determination part with which the onboard equipment which concerns on Embodiment 2 is provided. 6 is a flowchart illustrating an operation of a determination unit included in the portable device according to the second embodiment. 6 is a time chart showing a communication method for realizing a smart entry function by the vehicle-mounted device and the portable device according to the second embodiment. It is a flowchart which shows operation | movement of the determination part with which the onboard equipment which concerns on Embodiment 3 of this invention is provided. It is a flowchart which shows operation | movement of the determination part with which the portable device which concerns on Embodiment 3 of this invention is provided. 10 is a time chart showing a communication method for realizing a smart entry function by an in-vehicle device and a portable device according to a third embodiment.

Embodiment 1 FIG.
The communication system for vehicle equipment remote control according to the first embodiment of the present invention includes an in-vehicle device 10 shown in FIG. 1 and a portable device 20 shown in FIG. Here, the door lock which locks / unlocks the door of this vehicle based on the collation result by performing wireless communication between the vehicle-mounted device 10 mounted on the vehicle and the portable device 20 possessed by the user. The communication system is used to control vehicle equipment such as a unit (not shown). Hereinafter, a door lock part will be described as an example of a vehicle device.

The vehicle-mounted device 10 shown in FIG. 1 includes a door detection unit 11, a determination unit 12, a transmission unit 13, a power control unit 14, a transmission / reception switching unit 15, an antenna unit 16, and a reception unit 17. .
The door detection unit 11 detects the open / closed state of the door of the vehicle on which the vehicle-mounted device 10 is mounted, and notifies the determination unit 12 of the open / closed state.

The determination unit 12 receives the detection signal of the door open state or the closed state from the door detection unit 11 and outputs a signal corresponding to the door open / close state to the transmission unit 13. In addition, the determination unit 12 controls the power control unit 14 to adjust transmission power, or obtain a received signal from the reception unit 17. The determination unit 12 switches the transmission function / reception function of the transmission / reception switching unit 15 so that signals can be transmitted to and received from the portable device 20. Further, locking / unlocking of the door lock unit is controlled in accordance with the received signal.
The first determination unit includes the determination unit 12.

The transmission unit 13 performs transmission processing such as modulating the signal output from the determination unit 12 with a predetermined modulation method, and transmits the signal from the antenna unit 16 via the power control unit 14 and the transmission / reception switching unit 15. The transmission / reception switching unit 15 is connected to the transmission / reception switching unit 15, and switches between selection of the transmission function and the reception function under the control of the determination unit 12. The antenna unit 16 transmits and receives radio waves of, for example, UHF band (315 MHz) to and from the portable device 20. When receiving the radio wave received by the antenna unit 16 via the transmission / reception switching unit 15, the reception unit 17 performs a reception process such as detecting (demodulating) the radio wave modulated by a predetermined modulation method, 12 is output.
The first transmission / reception unit includes a transmission unit 13, a transmission / reception switching unit 15, an antenna unit 16, and a reception unit 17.

  The power control unit 14 controls transmission power in accordance with an instruction from the determination unit 12. Details will be described later.

  2 includes an antenna unit 21, a transmission / reception switching unit 22, a transmission unit 23, a determination unit 24, an operation detection unit 25, a reception unit 26, a startup circuit unit 27, and a startup level control. And a polling circuit unit 29.

For example, the antenna unit 21 transmits and receives radio waves in the UHF band (315 MHz) to and from the vehicle-mounted device 10. The transmission / reception switching unit 22 is connected to the antenna unit 21 and switches between transmission function and reception function selection under the control of the determination unit 24. The transmission unit 23 performs transmission processing such as modulating the signal output from the determination unit 24 using a predetermined modulation method, and transmits the signal from the antenna unit 21 via the transmission / reception switching unit 22. The receiving unit 26 receives the radio wave received by the antenna unit 21 via the transmission / reception switching unit 22, performs reception processing such as detecting (demodulating) the radio wave modulated by a predetermined modulation method, and outputs the received signal to the determination unit 24. To do.
The second transmission / reception unit includes an antenna unit 21, a transmission / reception switching unit 22, a transmission unit 23, and a reception unit 26.

The determination unit 24 receives the locking / unlocking operation detection signal from the operation detection unit 25 and outputs a signal corresponding to the operation content to the transmission unit 23. In addition, the determination unit 24 controls the activation level control unit 28 to adjust the activation level of the portable device 20 and acquires a received signal from the reception unit 26. Moreover, the determination part 24 switches the transmission function / reception function of the transmission / reception switching part 22 so that a signal can be transmitted / received between the onboard equipment 10. Furthermore, the determination unit 24 has a built-in timer 24a and can perform timer interruption.
The second determination unit includes the determination unit 24.

  The operation detection unit 25 detects a door locking / unlocking instruction input by the user operating the portable device 20 and notifies the determination unit 24 of a locking / unlocking operation detection signal.

  The activation circuit unit 27 activates each unit of the portable device 20 necessary for signal reception at the activation level set in the activation level control unit 28. The activation level control unit 28 controls the activation level of the activation circuit unit 27 in accordance with an instruction from the determination unit 24. The polling circuit unit 29 operates the activation circuit unit 27 and the activation level control unit 28 periodically.

FIG. 3 is a block diagram illustrating an internal configuration of the power control unit 14 of the vehicle-mounted device 10. The power control unit 14 is provided with a plurality of amplification units having a certain amplification amount, and an ON / OFF signal from the determination unit 12 is input to each amplification unit. In the example of FIG. 3, four stages of amplifiers 141 to 144 are provided. Each amplifier 141-144 amplifies transmission power according to the ON / OFF signal, thereby realizing control of transmission power.
Although illustration is omitted, the activation level control unit 28 of the portable device 20 is also provided with a plurality of amplification units having a certain amplification amount in accordance with the ON / OFF signal from the determination unit 24, similarly to the power control unit 14. Realize control of startup level. In order to lower the activation level, it is necessary to amplify the signal from the vehicle-mounted device 10 in the previous stage. Therefore, when the activation level is lowered, the current consumption increases.

FIG. 4 is a block diagram illustrating an internal configuration of the activation circuit unit 27 of the portable device 20. The activation circuit unit 27 includes a detection unit 271 and a synchronization signal determination unit 272. The detection unit 271 detects the received signal strength from the vehicle-mounted device 10 and also detects, for example, an ASK (Amplitude Shift Keying) modulated synchronization portion. The synchronization signal determination unit 272 confirms whether or not the synchronization signal detected by the detection unit 271 is a desired synchronization signal, and activates each unit of the portable device 20 in the case of the desired synchronization signal. When the portable device 20 is activated, wireless communication with the vehicle-mounted device 10 can be performed.
Thereby, it becomes possible to start up with a signal from the desired vehicle-mounted device 10 without inadvertently starting up the portable device 20.

Next, operation | movement of the determination part 12 of the onboard equipment 10 which concerns on this Embodiment 1 is demonstrated using the flowchart shown in FIG.
Step ST1 is an initial state, and the determination unit 12 waits for a door open detection signal from the door detection unit 11. When the determination unit 12 receives the notification of the door open detection signal (step ST2), the determination unit 12 switches the transmission / reception switching unit 15 to the transmission function (step ST3), and outputs an ON / OFF signal to the power control unit 14 to increase the transmission power. Control to "weak" (step ST4). Then, a question signal is output from the determination unit 12 to the transmission unit 13, and the question signal is transmitted to the portable device 20 (step ST5).

  Subsequently, in order to receive the response signal from the portable device 20, the determination unit 12 switches the transmission / reception switching unit 15 to the reception function (step ST6) and waits for reception of the response signal by the reception unit 17 (step ST7). . When there is a response signal within a predetermined time (step ST7 “YES”), the determination unit 12 then waits for a door closing detection signal from the door detection unit 11 (step ST8). When there is a notification of the door closing detection signal (step ST8 “YES”), the transmission / reception switching unit 15 is switched to the transmission function (step ST10), and the transmission power of the power control unit 14 is controlled to “strong” (step ST11). Then, a transmission stop signal is output to the transmission unit 13, and the transmission stop signal is transmitted to the portable device 20 (step ST12). After transmitting the transmission stop signal, the process returns to step ST2 and waits for the door open detection signal to be input.

  On the other hand, when there is no response signal within a predetermined time in step ST7 (step ST7 “NO”), the determination unit 12 then waits for a door closing detection signal from the door detection unit 11 (step ST9). If there is no notification of the door closing detection signal (“NO” in step ST9), the process returns to step ST3 again, and a process for retransmitting the question signal to the portable device 20 is performed. If there is a notification of the door closing detection signal even if there is no response signal (step ST7 “NO”, step ST9 “YES”), the process proceeds to step ST10 to transmit a transmission stop signal to the portable device 20. I do.

Next, the operation of the determination unit 24 of the portable device 20 according to the first embodiment will be described using the flowchart shown in FIG.
Step ST21 is an initial state, and in the subsequent step ST22, a standby state is entered and various interrupts are waited for. There are three types of interrupts to the determination unit 24: an interrupt from the activation circuit unit 27, an interrupt of the built-in timer 24a, and an interrupt from the operation detection unit 25. When receiving the interrupt signal, the determination unit 24 determines where the interrupt is from (step ST23).

In the case of an interruption from the activation circuit unit 27 (step ST24), this interruption indicates that the portable device 20 has been activated by receiving a desired inquiry signal from the vehicle-mounted device 10 for realizing the smart entry function. Therefore, the determination unit 24 switches the transmission / reception switching unit 22 to the reception function (step ST25), and determines whether the reception unit 26 has received the question signal from the vehicle-mounted device 10 (step ST26). If there is a question signal within a certain time (step ST26 “YES”), the determination unit 24 switches the transmission / reception switching unit 22 to the transmission function (step ST27), and sends information for code verification to the transmission unit 23. The response signal including this is output, and this response signal is transmitted toward the vehicle-mounted device 10 (step ST28). And the timer 24a which counts the timing which transmits a response signal regularly is started (step ST29), and it returns to the standby state of step ST22 again.
On the other hand, when there is no question signal within a certain time in step ST26 (step ST26 “NO”), the determination unit 24 subsequently determines whether or not the reception unit 26 has received a transmission stop signal from the vehicle-mounted device 10. (Step ST30). If there is a transmission stop signal (“YES” in step ST30), the running timer 24a is stopped (step ST31), and the process returns to the standby state in step ST22 again. If there is no transmission stop signal (“NO” at step ST30), the process returns to the standby state at step ST22.

  In the case of an interrupt from the timer 24a (step ST32), this interrupt indicates a periodic transmission timing of a response signal for realizing the smart entry function. Therefore, the determination unit 24 switches the transmission / reception switching unit 22 to the transmission function (step ST33), performs a process of transmitting a response signal to the portable device 20 (step ST34), and a timer 24a for periodically transmitting the response signal. Is activated (step ST35), and the process returns to the standby state of step ST22.

  In the case of an interruption from the operation detection unit 25 (step ST36), this interruption is for a remote operation function (so-called keyless entry function), so that the user operates the operation detection unit 25 to lock / unlock the door lock unit of the vehicle. Indicates that the operation has been performed. Therefore, the determination unit 24 switches the transmission / reception switching unit 22 to the transmission function (step ST37), and outputs the unlocking signal or the locking signal corresponding to the user operation signal interrupted from the operation detection unit 25 to the transmission unit 23. This signal is transmitted to 10 (step ST38). And it returns to the standby state of step ST22 again.

  In order to realize the smart entry function, the vehicle-mounted device 10 collates the code included in the response signal received from the portable device 20 by the above communication method, and operates the door lock unit after detecting the door closed state to lock the device. do it.

FIG. 7 is a diagram for explaining a communication method for realizing the smart entry function by the vehicle-mounted device 10 and the portable device 20 according to the first embodiment. FIG. 7A shows a state where a user with a portable device 20 (not shown) opens the vehicle door and gets in, and FIG. 7B shows a transition of received power of radio waves transmitted by the vehicle-mounted device 10 at that time. An example is shown.
In the transmission of a signal using radio waves, there is a so-called null point where the electric field strength as shown in (I) and (III) of FIG. 7B drops due to the combination of the direct wave and the reflected wave from the vehicle body. . Therefore, using the fact that the portable device 20 is held by the user and moves with the user, the vehicle-mounted device 10 estimates the movement timing of the portable device 20, and periodically transmits a question signal from the vehicle-mounted device 10 during the movement. . The estimation of whether or not the user moves is based on the determination unit 12 receiving a notification of a door open detection signal from the door detection unit 11. By periodically transmitting the question signal in this way, even if the portable device 20 cannot receive the question signal in (I) of FIG. 7B, it can be received in (II). Thus, even when communication is originally impossible, communication can be successfully performed by attempting communication from the vehicle-mounted device 10 a plurality of times.
Moreover, it can suppress that a question signal flies to an unnecessary area by transmitting a question signal from the onboard equipment 10 to the portable device 20 with weak electric power.

In addition, when the door is closed, the mobile device 20 exists at the null point as shown in (III) of FIG. 7B by transmitting a transmission stop signal from the vehicle-mounted device 10 to the mobile device 20 with strong power. Even in such a case, the periodic transmission of the response signal of the portable device 20 can be stopped.
Further, until the user closes the door of the vehicle and moves to the next operation, the portable device 20 can periodically transmit a response signal, and further reduce the area where communication is impossible.

  As described above, according to the first embodiment, the vehicle-mounted device 10 wirelessly communicates with the portable device 20 by switching the antenna unit 16 with the door detection unit 11 that detects the open / closed state of the vehicle door and the transmission / reception switching unit 15. When the door detection state is detected by the transmission unit 13 and the reception unit 17 that perform communication and the door detection unit 11, a question signal is periodically transmitted from the transmission unit 13 until the reception unit 17 receives a response signal from the portable device 20. It was set as the structure provided with the determination part 12 to transmit. In addition, the portable device 20 switches the antenna unit 21 with the transmission / reception switching unit 22 to perform wireless communication with the vehicle-mounted device 10, and transmits a question signal from the vehicle-mounted device 10 with the reception unit 26. When receiving, a response signal including a code for locking the door by remotely controlling the door lock unit is transmitted from the transmission unit 23. For this reason, by estimating the timing at which the portable device 20 moves in the vehicle-mounted device 10 and trying communication multiple times while moving, it is possible to try communication multiple times at different positions and timings without using multiple antennas. Thus, the area where communication is impossible can be reduced. As a result, reliable code verification around the vehicle can be realized.

  Further, according to the first embodiment, when the determination unit 24 of the portable device 20 receives the interrogation signal from the vehicle-mounted device 10 by the reception unit 26, the transmission unit until the transmission stop signal is received from the vehicle-mounted device 10. 23, the response signal is periodically transmitted, the determination unit 12 of the vehicle-mounted device 10 receives the response signal from the portable device 20 by the reception unit 17, and detects the door closed state by the door detection unit 11. In this case, a transmission stop signal is transmitted from the transmission unit 13. For this reason, until the user closes the door of the vehicle and moves to the next operation, the response signal from the portable device 20 can be repeatedly transmitted, and the area where communication is impossible can be further reduced.

Embodiment 2. FIG.
In the first embodiment, the question signal transmitted from the vehicle-mounted device 10 and the transmission stop signal are set to the preset power “weak” and power “strong”, thereby suppressing the question signal from flying to an unnecessary area. However, the transmission stop signal is surely received by the portable device 20. On the other hand, in this Embodiment 2, the transmission stop signal from onboard equipment 10 is received more reliably by controlling the starting level of portable device 20 based on the reception power of the response signal received from onboard equipment 10. It can be so.
Since the vehicle-mounted device 10 and the portable device 20 according to the second embodiment have the same configuration as the vehicle-mounted device 10 and the portable device 20 shown in FIGS. 1 and 2 in the drawings, FIG. 1 and FIG. This is explained with the aid of it.

  FIG. 8 is a block diagram showing an internal configuration of receiving unit 26 of portable device 20 according to Embodiment 2 of the present invention. The receiver 26 is provided with a demodulator 261 and an electric field strength acquisition unit 262. The demodulator 261 demodulates an interrogation signal from the vehicle-mounted device 10. The electric field strength acquisition unit 262 measures the electric field strength of the received question signal.

  Next, operation | movement of the determination part 12 of the onboard equipment 10 which concerns on this Embodiment 2 is demonstrated using the flowchart shown in FIG. The operation of the determination unit 12 is substantially the same as the operation of the flowchart shown in FIG. 5, but in the second embodiment, the transmission power of the question signal or the transmission stop signal is not changed after the transmission switching of steps ST3 and ST10. Send each signal. If a response signal is received from the portable device 20 (“YES” in step ST7), the transmission / reception switching unit 15 is newly switched to the transmission function in step ST51, and the reception response signal is transmitted to the portable device 20 in step ST52. To do.

  Next, the operation of the determination unit 24 of the portable device 20 according to the second embodiment will be described using the flowchart shown in FIG. The operation of the determination unit 24 is substantially the same as the operation of the flowchart shown in FIG. 6, but in the second embodiment, the transmission / reception switching unit 22 is received in steps ST61 and ST64 after the response signals are transmitted in steps ST28 and ST34. Switching to the function, it is determined in steps ST62 and ST65 whether or not the reception response signal from the vehicle-mounted device 10 has been received within a certain time. When the reception response signal is received (steps ST62 “YES”, ST65 “YES”), the determination unit 24 subsequently acquires the electric field strength of the reception response signal from the reception unit 26 in steps ST63 and ST66, and the activation level control unit. 28 is controlled to a level that can be activated by the electric field strength. As a method for controlling the activation level, for example, control is performed so that “reception electric field intensity> activation level”. Note that the internal configuration of the activation level control unit 28 is as shown in FIG.

Next, a communication method for realizing the smart entry function by the vehicle-mounted device 10 and the portable device 20 according to the second embodiment will be described using the time chart shown in FIG.
When the vehicle-mounted device 10 detects the door open state and transmits a question signal (step ST101), the portable device 20 receives and starts the question signal and repeatedly returns a response signal (step ST102). Upon receiving the response signal, the vehicle-mounted device 10 returns a reception response signal, and the portable device 20 receives the reception response signal, measures the electric field strength, and sets the activation level according to the electric field strength (step ST103). Subsequently, the response signal is repeatedly returned (step ST104). When the vehicle-mounted device 10 detects the door closed state, the vehicle-mounted device 10 transmits a transmission stop signal (step ST105), the portable device 20 receives the transmission stop signal at the set activation level, and ends the return of the response signal.

  With such a configuration, it is possible to reduce areas where communication is impossible. Further, the activation level of the portable device 20 can be controlled so that the portable device 20 can reliably receive the transmission stop signal transmitted by the vehicle-mounted device 10, and the transmission of the response signal from the portable device 20 is repeated unnecessarily. Excessive battery consumption can be suppressed.

  As described above, according to the second embodiment, the determination unit 12 of the vehicle-mounted device 10 is configured to transmit the reception response signal from the transmission unit 13 when the reception unit 17 receives the response signal from the portable device 20. Further, the portable device 20 is configured to include an electric field strength acquisition unit 262 that measures the electric field strength of the reception response signal from the vehicle-mounted device 10 and an activation level control unit 28 that controls the activation level of the portable device 20. The unit 24 sets the activation level of the activation level control unit 28 based on the electric field intensity measured by the electric field intensity acquisition unit 262. For this reason, even when the portable device 20 stops moving at the null point when the door closed state is detected, the portable device 20 receives the transmission stop signal from the vehicle-mounted device 10 and reliably stops the periodic transmission of the response signal. As a result, the current consumption of the portable device 20 can be suppressed.

  In the second embodiment, power control of the interrogation signal and the transmission stop signal of the vehicle-mounted device 10 is not particularly performed. However, the present invention is not limited to this, and transmission of the interrogation signal is the same as in the first embodiment. The power may be controlled to be “weak” and the transmission power of the transmission stop signal may be controlled to “strong”. In the case of this configuration, the portable device 20 can receive the transmission stop signal more reliably.

Embodiment 3 FIG.
In the first and second embodiments, the transmission stop signal transmitted from the vehicle-mounted device 10 is controlled to be a predetermined power. In the third embodiment, the power of the transmission stop signal transmitted from the vehicle-mounted device 10 is controlled. Is configured to be variably controlled based on the received power of the response signal from the portable device 20.
Since the vehicle-mounted device 10 and the portable device 20 of the third embodiment have the same configuration as the vehicle-mounted device 10 and the portable device 20 shown in FIG. 1 and FIG. 2, FIG. 1 and FIG. This is explained with the aid of it. Moreover, the internal structure of the receiving part 26 of this Embodiment 3 is as showing in FIG.

Next, operation | movement of the determination part 12 of the onboard equipment 10 which concerns on this Embodiment 3 is demonstrated using the flowchart shown in FIG. The operation of the determination unit 12 is substantially the same as the operation of the flowcharts shown in FIG. 5 and FIG. 9, but in the third embodiment, the transmission power is newly set to “weakest” in step ST71 after transmission switching in step ST3. The power control unit 14 is controlled so that the interrogation signal is transmitted with the weakest power in the following step ST5. When the response signal from the portable device 20 is received in step ST7 (step ST7 “YES”), the determination unit 12 switches the transmission / reception switching unit 15 to the transmission function in step ST51, and the reception response in step ST52. A signal is transmitted to the portable device 20. In step ST72, the transmission / reception switching unit 15 is switched to the reception function again, and the transmission power of the power control unit 14 is controlled based on the received power of the received response signal (step ST73). Thereby, the transmission stop signal is transmitted with transmission power based on the power of the response signal (step ST12).
The determination unit 12 sets the transmission power value based on the power of the response signal so that, for example, “transmission power of the portable device 20−response signal reception power <transmission power of the power control unit 14−activation level of the portable device 20”. By controlling, a transmission stop signal can be reliably transmitted to the portable device 20. Note that the response signal from the portable device 20 includes information (electric field strength) necessary for the vehicle-mounted device 10 to determine the transmission power value.

  Next, the operation of the determination unit 24 of the portable device 20 according to the third embodiment will be described using the flowchart shown in FIG. The operation of the determination unit 24 is substantially the same as the operation of the flowcharts shown in FIGS. 6 and 10, but in the third embodiment, after receiving the reception response signal from the vehicle-mounted device 10 in steps ST 62 and ST 65, a new operation is performed. In steps ST81 and ST83, the electric field strength of the reception response signal is measured and held. And the determination part 24 gives the electric field strength measured and hold | maintained last time to the response signal transmitted by interruption of the timer 24a after step ST32 (step ST82). Thereby, the electric field strength can be notified to the vehicle-mounted device 10.

Next, a communication method for realizing the smart entry function by the vehicle-mounted device 10 and the portable device 20 according to the third embodiment will be described using the time chart shown in FIG.
When the vehicle-mounted device 10 detects the door open state and transmits an interrogation signal with the weakest power (step ST111), the portable device 20 receives and activates the interrogation signal and repeatedly returns a response signal (step ST112). . Upon receiving the response signal, the vehicle-mounted device 10 transmits a reception response signal, and the portable device 20 receives this reception response signal and measures the electric field strength (step ST113), and adds information on the electric field strength to the response signal. Subsequently, it is repeatedly returned (step ST114). The vehicle-mounted device 10 sets transmission power according to the electric field strength included in the response signal, and transmits a transmission stop signal with the transmission power when detecting the door closed state (step ST115). The portable device 20 receives this transmission stop signal and finishes returning the response signal.

  With such a configuration, it is possible to delete an area where communication is impossible. In addition, since it is not necessary to lower the activation level in the portable device 20 in order to receive the transmission stop signal from the vehicle-mounted device 10, there is no increase in current consumption due to a decrease in the activation level. Furthermore, since the propagation loss between the portable device 20 and the vehicle-mounted device 10 can be estimated from the power of the response signal from the portable device 20 and the transmission power of the vehicle-mounted device 10 can be controlled, the signal of the vehicle-mounted device 10 is unnecessary. It is possible to appropriately notify the portable device 20 without transmitting to the area.

  As described above, according to the third embodiment, the vehicle-mounted device 10 includes the power control unit 14 that controls the power for transmitting a signal, and the determination unit 12 uses the transmission unit 13 to transmit a response signal from the portable device 20. When receiving a response signal to which information on the electric field strength from the portable device 20 is received by the receiving unit 17, the power of the power control unit 14 is changed based on the electric field strength. The transmission stop signal is transmitted from the transmission unit 13 with the power. Further, the portable device 20 is configured to include an electric field strength acquisition unit 262 that measures the electric field strength of the reception response signal from the vehicle-mounted device 10, and the determination unit 24 periodically transmits a response signal from the transmission unit 23. The information on the electric field strength measured by the electric field strength acquisition unit 262 is given and notified to the vehicle-mounted device 10. For this reason, even when the portable device 20 stops moving at the null point when the door closed state is detected, the portable device 20 reliably reduces the current consumption required for reception by lowering the activation level. The transmission stop signal from the vehicle-mounted device 10 can be received and the periodic transmission of the response signal can be stopped, and the current consumption of the portable device 20 can be suppressed.

  In the first to third embodiments, the door lock unit that locks / unlocks the door of the vehicle is exemplified as the vehicle device that is remotely controlled using the communication system for vehicle device remote control. However, the present invention is not limited thereto. However, the engine control unit that starts the engine of the vehicle may be remotely controlled.

  In addition, within the scope of the invention, the invention of the present application can be freely combined with each embodiment, modified any component of each embodiment, or omitted any component in each embodiment. Is possible.

  DESCRIPTION OF SYMBOLS 10 Onboard equipment, 11 Door detection part, 12 Judgment part, 13 Transmission part, 14 Power control part, 15 Transmission / reception switching part, 16 Antenna part, 17 Reception part, 20 Portable machine, 21 Antenna part, 22 Transmission / reception switching part, 23 Transmission Unit, 24 determination unit, 24a timer, 25 operation detection unit, 26 reception unit, 27 activation circuit unit, 28 activation level control unit, 29 polling circuit unit, 141 to 144 amplification unit, 261 demodulation unit, 262 electric field strength acquisition unit, 271 Detection unit, 272 Synchronization signal determination unit.

Claims (8)

In the communication system for vehicle device remote control that performs wireless communication between the on-vehicle device and the portable device, and the vehicle device is controlled based on the response signal when the on-vehicle device receives the response signal from the portable device,
The in-vehicle device is
A door detector for detecting the open / closed state of the vehicle door;
A first transmission / reception unit having an antenna and performing wireless communication with the portable device;
A first determination unit that controls the first transmission / reception unit to transmit / receive a signal,
The first determination unit, when the door detection unit detects the open state of the door, periodically transmits a question signal from the first transmission / reception unit until receiving a response signal from the portable device,
The portable device is
A second transmission / reception unit having an antenna and performing wireless communication with the vehicle-mounted device;
A second determination unit that controls the second transmission / reception unit to transmit / receive a signal,
When the second transmitter / receiver receives the interrogation signal from the vehicle-mounted device, the second determination unit transmits a response signal for remotely controlling the vehicle device to perform a predetermined operation. A communication system for remote control of vehicle equipment, characterized by being transmitted from a unit. When the second transmitter / receiver receives the interrogation signal from the vehicle-mounted device, the second determination unit of the portable device periodically transmits a response signal until receiving the transmission stop signal from the vehicle-mounted device,
When the first transmitter / receiver receives a response signal from the portable device and the door detector detects a closed state of the door, the first determination unit of the on-vehicle device periodically transmits the response signal. The communication system for vehicle equipment remote control according to claim 1, wherein a transmission stop signal for stopping transmission is transmitted from the first transmission / reception unit. When the first transmission / reception unit receives a response signal from the portable device, the first determination unit of the vehicle-mounted device causes the reception response signal to be returned from the first transmission / reception unit,
The portable device is
An electric field strength acquisition unit for measuring the electric field strength of the reception response signal from the in-vehicle device;
An activation level control unit for controlling the activation level of the portable device,
3. The vehicle device remote control according to claim 1, wherein the second determination unit sets the activation level of the activation level control unit based on the electric field intensity measured by the electric field intensity acquisition unit. Communications system. The portable machine
An electric field strength acquisition unit that measures the electric field strength of the reception response signal from the on-vehicle device
The second determination unit gives information on the electric field strength measured by the electric field strength acquisition unit to the response signal that is periodically transmitted from the second transmission / reception unit, and notifies the vehicle-mounted device,
The in-vehicle device is
A power control unit for controlling power for transmitting signals;
The first determination unit returns a reception response signal when the first transmission / reception unit receives a response signal from the portable device, and the first transmission / reception unit gives information on the electric field strength from the portable device. 3. The transmission stop signal is transmitted from the first transmission / reception unit with the power by setting the power of the power control unit based on the electric field strength when the received response signal is received. Communication system for vehicle equipment remote control. In the communication method for vehicle device remote control that performs wireless communication between the vehicle-mounted device and the portable device and controls the vehicle device based on the response signal when the vehicle-mounted device receives the response signal from the portable device,
When the vehicle-mounted device detects an open state of a vehicle door, a question signal transmission step of periodically transmitting a question signal until receiving a response signal from the portable device;
A response signal transmitting step of transmitting a response signal for remotely controlling the vehicle device to perform a predetermined operation when the portable device receives the question signal transmitted from the vehicle-mounted device in the question signal transmitting step; A communication method for remote control of vehicle equipment, comprising: In the response signal transmission step, the portable device periodically transmits a response signal,
The on-vehicle device receives the response signal transmitted from the portable device in the response signal transmitting step, and when detecting the closed state of the door of the vehicle, the onboard device stops transmission of the response signal periodically. A transmission stop signal transmission step of transmitting a stop signal;
The portable device includes a response signal transmission stop step of stopping periodic transmission of a response signal when receiving the transmission stop signal transmitted from the vehicle-mounted device in the transmission stop signal transmission step. The communication method for vehicle equipment remote control according to claim 5. When the in-vehicle device receives the response signal transmitted from the portable device in the response signal transmission step, the reception response signal transmission step of returning the reception response signal;
When the portable device receives the reception response signal transmitted from the vehicle-mounted device in the reception response signal transmission step, the electric field strength of the reception response signal is measured, and the portable device is activated based on the measured electric field strength An activation level control step for controlling the level,
7. The communication method for vehicle equipment remote control according to claim 6, wherein, in the response signal transmission stop step, the portable device receives a transmission stop signal from the vehicle-mounted device at the start level controlled in the start level control step. . When the in-vehicle device receives the response signal transmitted from the portable device in the response signal transmission step, the reception response signal transmission step of returning the reception response signal;
When the portable device receives the reception response signal transmitted from the vehicle-mounted device in the reception response signal transmission step, it measures the electric field strength of the reception response signal, and periodically transmits the response signal of the electric field strength to the response signal. Electric field strength notification step of giving information and notifying the vehicle-mounted device;
When the vehicle-mounted device receives a response signal to which information on the electric field strength transmitted from the portable device is added in the electric field strength notification step, transmission for controlling power for transmitting a transmission stop signal based on the electric field strength A power control step,
The communication method for vehicle equipment remote control according to claim 6, wherein in the transmission stop signal transmission step, the vehicle-mounted device transmits a transmission stop signal with the power controlled in the transmission power control step.

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