JP2007259057A - In-vehicle signal receiver and signal receiving method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the power consumption of the receiver as a whole, by improving the power consumption at signal reception. <P>SOLUTION: The in-vehicle signal receiver 100, for receiving a wireless signal output from a remote controller 200 carried by an operator, includes a receiving circuit 102 for receiving wireless signal; and an ECU 101 (control section 111) that executes a first operating mode (sleep mode) executed at a first operating frequency and awaiting the reception of the wireless signal, a signal processing mode executed at a second operating frequency higher than the operating frequency of the sleep mode and receiving the wireless signal, and a signal determination mode, executed by an operating frequency between the first and the second frequencies and determining the reception of the wireless signal. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an in-vehicle signal receiving apparatus and a signal receiving method, and in particular, a keyless device that can start driving an engine or lock / unlock a door in response to a radio signal from a remote controller carried by a driver. The present invention relates to an in-vehicle signal receiving apparatus and a signal receiving method suitable for an entry system.

  2. Description of the Related Art Conventionally, an in-vehicle signal receiving device that reduces power consumption has been proposed in a keyless entry system that can start driving an engine in accordance with a radio signal from a remote controller (see, for example, Patent Document 1). In such an in-vehicle signal receiving apparatus, the power supply of the receiving circuit is intermittently turned on / off at the time of waiting for a radio signal from a remote controller, and two types of frequencies having different frequencies are provided to a CPU (signal analysis unit) that analyzes the radio signal. A clock is provided to operate at the higher operating frequency (16 MHz) when the power source is on, while operating at the lower operating frequency (32 KHz) in the off state.

That is, when the power supply of the receiving circuit is off, the CPU operating frequency is set to 32 KHz, and the CPU operating function is minimized to suppress power consumption. Then, at the same time as switching the power supply of the receiving circuit to the ON state, the CPU operating frequency is increased to 16 MHz, and it is determined whether or not a radio signal from the remote controller is detected. When the wireless signal is detected, the operation frequency (16 MHz) is maintained, and when the wireless signal is not detected, the operation frequency is lowered to 32 KHz again. This achieves a reduction in power consumption when the power supply of the receiving circuit is off.
Japanese Patent Laid-Open No. 9-289458

  However, in the field of the in-vehicle signal receiving apparatus as described above, reduction of power consumption is always demanded. For this reason, there is a demand for the development of an in-vehicle signal receiver that can realize further reduction in power consumption.

  The present invention has been made in view of such problems, and provides an in-vehicle signal receiving apparatus and a signal receiving method capable of reducing power consumption of the entire apparatus by improving power consumption at the time of signal reception. With the goal.

  An in-vehicle signal receiving device of the present invention is an in-vehicle signal receiving device that receives a radio signal output from a portable communication device carried by an operator, the receiving unit receiving the radio signal, and a first operation A first operation mode executed at a frequency and waiting for reception of the radio signal; a second operation mode executed at a second operation frequency higher than the first operation frequency and receiving the radio signal; and And a control unit that executes a third operation mode that is executed at an operation frequency between the first and second operation frequencies and that determines reception of the radio signal.

  According to this configuration, the third operation executed at an operating frequency between the operating frequency of the first operating mode (sleep mode described later) and the operating frequency of the second operating mode (signal processing mode described later). A mode (signal determination mode described later) is provided, and reception of a radio signal from the portable communication device is determined in the third operation mode. The power consumption in the device depends on the operating frequency. Therefore, when no radio signal is received in the third operation mode, the reception of the radio signal is not detected compared to the conventional configuration in which the operation frequency is switched in two stages by shifting the operation mode to the first operation mode. Since the power consumption in the case can be reduced, the power consumption of the entire apparatus can be reduced.

  In the on-vehicle signal receiving device, the control unit shifts to the third operation mode at a predetermined time interval in the first operation mode and detects reception of the radio signal in the third operation mode. It is preferable to shift to the second operation mode while shifting to the first operation mode when reception of the radio signal is not detected. In this case, compared with the conventional configuration in which the operating frequency is switched in two stages, the power consumption when the reception of the radio signal from the portable communication device is not detected can be reduced, so the power consumption of the entire device is reduced. It is possible to reduce. On the other hand, when reception of the radio signal is detected, the radio signal can be reliably received in the second operation mode.

  In the in-vehicle signal receiving apparatus, the control unit may shift to the first operation mode after completing the reception processing of the radio signal in the second operation mode. In this case, since the radio signal reception process is completed in the second operation mode and the process shifts to the first operation mode with low power consumption, the power consumption after the radio signal reception process can be suppressed, and the entire apparatus can be further reduced. As a result, the power consumption can be reduced.

  The signal reception method of the present invention is a first operation mode that is executed at a first operating frequency and waits for reception of a radio signal output from a portable communication device carried by an operator, and is higher than the first operating frequency. A second operation mode executed at a second operating frequency and receiving the radio signal; and a third operation mode executed at an operating frequency between the first and second operating frequencies to determine reception of the radio signal. A signal reception method for receiving the wireless signal by switching an operation mode, wherein the wireless communication device shifts to the third operation mode at a predetermined time interval in the first operation mode, and transmits the wireless signal in the third operation mode. When reception is detected, the mode is shifted to the second operation mode, while when reception of the radio signal is not detected, the mode is shifted to the first operation mode.

  According to this method, the third operation mode (signal determination described later) executed at an operation frequency between the first operation mode (sleep mode described later) and the second operation mode (signal processing mode described later). Mode), and reception of a radio signal from the portable communication device is determined in the third operation mode. When the reception of the radio signal is detected in the third operation mode, the mode shifts to the second operation mode. On the other hand, when the reception of the radio signal is not detected, the mode shifts to the first operation mode. Compared with the conventional method of switching the operating frequency in stages, it is possible to reduce the power consumption when the reception of the radio signal from the portable communication device is not detected, so that the power consumption of the entire apparatus can be reduced. .

  In the signal reception method, it is preferable that the wireless signal shift process is performed after the radio signal reception process is completed in the second operation mode. In this case, since the radio signal reception process is completed in the second operation mode and the process shifts to the first operation mode with low power consumption, the power consumption after the radio signal reception process can be suppressed, and the entire apparatus can be further reduced. As a result, the power consumption can be reduced.

  According to the present invention, it is possible to reduce the power consumption of the entire apparatus by improving the power consumption during signal reception.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a functional block diagram showing a configuration of an in-vehicle signal receiving apparatus (hereinafter, appropriately referred to as “receiving apparatus”) 100 according to an embodiment of the present invention.

  The receiving apparatus 100 according to the present embodiment performs, for example, various processes in accordance with a radio signal from a remote controller (hereinafter abbreviated as “remote controller”) 200 as a portable communication device carried by a driver (operator). Applies to keyless entry systems that enable execution. For example, the receiving device 100 executes processing such as starting driving of the engine or locking / unlocking the door in accordance with a radio signal from the remote controller 200.

  In the following, a case where door locking / unlocking processing is executed in accordance with a radio signal from the remote controller 200 will be described. However, the processing executed by receiving apparatus 100 according to the present embodiment is not limited to this, and can be changed as appropriate.

  As shown in FIG. 1, the receiving apparatus 100 according to the present embodiment includes an ECU 101 that controls the entire apparatus, a receiving circuit 102 connected to the ECU 101, a first clock 103, a second clock 104, and an authentication code. The storage unit 105 is included. Further, the ECU 101 includes various switches 106 including a switch for instructing locking / unlocking of the door disposed inside the door of the vehicle, and locking / unlocking in the locking mechanism unit 107 mounted on the door of the vehicle. A lock driving unit 108 for locking is connected.

  The ECU 101 determines reception of a radio signal from the remote controller 200 and executes a door locking / unlocking process according to the radio signal. At this time, the ECU 101 executes a radio signal reception process and a lock / unlock process by switching a plurality of operation modes. Specifically, a signal determination mode for determining reception of a radio signal from the remote controller 200, a radio signal from the remote controller 200 are received, and processing according to the radio signal (here, locking / unlocking processing) is executed. Processing is performed in three operation modes: a signal processing mode and a sleep mode that waits for reception of a radio signal from the remote controller 200 and reduces power consumption. The sleep mode corresponds to the first operation mode, the signal processing mode corresponds to the second operation mode, and the signal determination mode corresponds to the third operation mode.

  These three types of operation modes differ in the operation frequency (hereinafter referred to as “operation clock”) at which each operation mode is executed by the ECU 101. Specifically, the signal determination mode is executed with an operation clock of 2 MHz, the signal processing mode is executed with an operation clock of 16 MHz, and the sleep mode is executed at 32 KHz. The power consumption in the receiving apparatus 100 depends on the operation clock when the ECU 101 executes each operation mode. For this reason, in the three types of operation modes, power consumption is the smallest in the sleep mode, followed by the signal determination mode is the smallest, and the signal processing mode is the largest.

  The reception circuit 102 functions as a reception unit and receives a radio signal transmitted from the remote controller 200. The first clock 103 and the second clock 104 provide operation clocks when the ECU 101 executes each operation mode described later. The first clock 103 provides a 4 MHz operating clock, while the second clock 104 provides a 32 KHz operating clock. The authentication code storage unit 105 stores authentication codes assigned in advance to the receiving device 100 and the remote controller 200. Such an authentication code is included in a wireless signal from the remote controller 200, and is used when determining permission to lock / unlock the door.

  The ECU 101 includes a reception determination unit 109 that determines reception of a radio signal from the remote controller 200, a clock control unit 110 that controls an operation clock when the ECU 101 executes each operation mode described later, and a control that controls the entire ECU 101. Part 111.

  The reception determination unit 109 determines reception of a radio signal from the remote controller 200. Specifically, the reception circuit 102 receives the received radio signal and determines whether the radio signal is a regular radio signal including a door locking / unlocking instruction or noise. Only when a legitimate wireless signal is received, this is notified to the control unit 111.

  The clock controller 110 generates operation clocks for the three operation modes in accordance with operation clocks provided from the first clock 103 and the second clock 104. Specifically, in the signal determination mode that operates with a 2 MHz operation clock, a 2 MHz operation clock is generated by dividing the 4 MHz operation clock provided from the first clock 103. In the signal processing mode that operates with the 16 MHz operation clock, the 16 MHz operation clock is generated by multiplying the 4 MHz operation clock provided from the first clock 103 by four times. In the sleep mode that operates with the 32 kHz operating clock, the 32 kHz operating clock provided from the second clock 104 is used as it is.

  The control unit 111 is configured by a CPU, for example, and controls each component included in the ECU 101. Then, the operation mode to be executed is switched according to an internal factor or an external factor, and a process according to the switched operation mode is executed. Note that factors and timings when the operation mode is switched in the control unit 111 will be described later.

  Further, the control unit 111 instructs the lock drive unit 108 to lock / unlock the door. At this time, the control unit 111 refers to the authentication code stored in the authentication code storage unit 105 and determines whether the door is allowed to be locked / unlocked according to the authentication code included in the wireless signal from the remote controller 200. Only allow the door to be locked / unlocked if the authorization code is correct.

  Here, the configuration of remote controller 200 that transmits a radio signal to receiving apparatus 100 according to the present embodiment will be described. FIG. 2 is a functional block diagram showing a configuration of remote controller 200 that transmits a radio signal to receiving apparatus 100 according to the present embodiment.

  As shown in FIG. 2, the remote control 200 includes a control unit 201 that controls the entire remote control 200, and includes a transmission switch 202, a transmission circuit 203, an authentication code storage unit 204, and the like connected to the control unit 201. Is done.

  The transmission switch 202 is selected when a driver or the like carrying the remote controller 200 locks or unlocks the door. The transmission circuit 203 converts a transmission signal to be transmitted to the reception device 100 into a radio signal and transmits it. The authentication code storage unit 204 stores authentication codes assigned in advance to the remote controller 200 and the receiving device 100. The control unit 201 uses the components of the remote controller 200 to perform control to transmit a radio signal to the receiving device 100 in response to an instruction from a driver or the like.

  When receiving a radio signal from remote controller 200, receiving apparatus 100 according to the present embodiment performs processing while switching the operation mode described above. Hereinafter, processing when receiving a radio signal from remote controller 200 in receiving apparatus 100 according to the present embodiment will be described with reference to FIGS. FIG. 3 is a flowchart for explaining processing when receiving a radio signal from remote controller 200 in receiving apparatus 100 according to the present embodiment. FIG. 4 is a transition state diagram of operation modes in receiving apparatus 100 according to the present embodiment.

  As shown in FIG. 3, when the keyless entry system is activated, the control unit 111 sets the operation mode to the sleep mode (step (hereinafter referred to as “ST”) 301). Thereby, the process of the control part 111 is performed at 32 KHz provided from the 2nd clock 104 as mentioned above. In the sleep mode, reception of a radio signal from the remote controller 200 is awaited and power consumption is reduced.

  In the sleep mode, control unit 111 determines whether a control signal output from various switches 106 has been received (ST302). For example, it is determined whether a control signal instructing a door locking / unlocking button by a driver in the driver's seat is received. When the control signal is received here, control section 111 sets the operation mode to the signal processing mode (ST307). As a result, the operation mode is switched from the sleep mode to the signal processing mode as indicated by an arrow A in FIG. The signal processing mode will be described later.

  If the control signal is not received in ST302, control section 111 determines whether a predetermined time has elapsed in the sleep mode (ST303). Here, the passage of the predetermined time is determined in order to shift from the sleep mode to the signal determination mode at predetermined time intervals. Until a predetermined time has elapsed, the process returns to ST301 and the sleep mode is continued.

  When a predetermined time has elapsed in ST303, control unit 111 sets the operation mode to the signal determination mode (ST304). As a result, the operation mode is switched from the sleep mode to the signal determination mode as indicated by an arrow B shown in FIG. Thereby, as described above, the processing of the control unit 111 is executed at 2 MHz obtained by dividing 4 MHz provided from the first clock 104. Reception of a radio signal from the remote controller 200 is determined based on such an operation clock.

  In signal determination mode, control unit 111 determines whether a radio signal has been received from remote controller 200 (ST305). When receiving the radio signal, control unit 111 sets the operation mode to the signal processing mode (ST307). As a result, the operation mode is switched from the signal determination mode to the signal processing mode as indicated by an arrow C shown in FIG. The signal processing mode will be described later.

  When a radio signal is not received in ST305, control unit 111 determines whether a predetermined time has elapsed in signal determination mode (ST306). Here, the elapse of the predetermined time is determined in order to shift to the sleep mode when no radio signal is received for a predetermined time in the signal determination mode. Here, when the predetermined time has elapsed in the signal determination mode, the control unit 111 returns the process to ST301 and sets the operation mode to the sleep mode. As a result, the operation mode is switched from the signal determination mode to the sleep mode as indicated by an arrow D shown in FIG. And the process after ST301 is performed again. Until a predetermined time has elapsed, the process returns to ST304 and the signal determination mode is continued.

  Here, the signal processing mode will be described. In the signal processing mode, as described above, the processing of the control unit 111 is executed at 16 MHz, which is four times the 4 MHz provided from the first clock 104. With such an operation clock, a radio signal is received from the remote controller 200, and processing corresponding to the content of the radio signal is executed. When control signals from various switches 106 are received, processing corresponding to the contents of the control signals is executed.

  Here, a door locking / unlocking process is executed. At this time, the control unit 111 refers to the authentication code included in the wireless signal received from the remote controller 200 and determines whether to allow the door to be locked / unlocked. When the authentication codes match and lock / unlock is permitted, a control signal for instructing lock / unlock is output to the lock drive unit 108.

  After setting the operation mode to the signal processing mode in ST307, control unit 111 determines whether the processing is completed (ST308). If the process has not ended, control section 111 returns the process to ST307 and continues the signal processing mode. On the other hand, when the process is completed, the process returns to ST301, and the operation mode is set to the sleep mode. As a result, the operation mode is switched from the signal processing mode to the sleep mode as indicated by an arrow E shown in FIG. And the process after ST301 is performed again. In this way, a series of processing when receiving a radio signal from remote controller 200 is completed in receiving apparatus 100 according to the present embodiment.

  FIG. 5 is a time chart for explaining the transition of the operation clock of ECU 101 (control unit 111) in receiving apparatus 100 according to the present embodiment. In FIG. 5, the transition of the operation clock when receiving a radio signal from the remote controller 200 is shown, and the transition of the operation clock when receiving a control signal from various switches 106 is omitted.

  In FIG. 5, it is assumed that the keyless entry system is activated at the time point t1 and the operation mode of the control unit 111 is set to the sleep mode. In this case, the process of the control unit 111 is first executed at 32 KHz. Since the sleep mode is maintained from time t1 until time t2 when a predetermined time elapses, the operation clock of the control unit 111 is also maintained at 32 KHz.

  When a predetermined time elapses from time t1, the operation mode of the control unit 111 is switched from the sleep mode to the signal determination mode at time t2. In this case, the operation clock of the control unit 111 is switched from 32 KHz to 2 MHz. Since the signal determination mode is maintained from time t2 to time t3 when a predetermined time elapses, the operation clock of the control unit 111 is also maintained at 2 MHz. Here, it is assumed that no radio signal is received from the remote controller 200.

  When a predetermined time elapses without detecting reception of a radio signal from the remote controller 200 from time t2, the operation mode of the control unit 111 is switched from the signal determination mode to the sleep mode at time t3. In this case, the operation clock of the control unit 111 is switched from 2 MHz to 32 KHz. Since the sleep mode is maintained from time t3 to time t4 when a predetermined time elapses, the operation clock of the control unit 111 is also maintained at 32 KHz.

  The operation mode and operation clock from the time point t3 to the time point t4 and the operation mode and operation clock from the time point t5 to the time point 6 are the same as the operation mode and operation clock from the time point t1 to the time point t2. Omitted. The operation mode and operation clock from the time point t4 to the time point t5 are the same as the operation mode and operation clock from the time point t2 to the time point t3, and thus description thereof is omitted.

  Here, it is assumed that reception of a radio signal from remote controller 200 is detected at time t7 before a predetermined time elapses in the signal determination mode that starts executing from time t6. In this case, at time t7, the operation mode of the control unit 111 is switched from the signal determination mode to the signal processing mode. In this case, the operation clock of the control unit 111 is switched from 2 MHz to 16 MHz. Since the signal processing mode is maintained from time t7 to time t8 when the door locking / unlocking process ends, the operation clock of the control unit 111 also maintains 16 MHz.

  When the door locking / unlocking process ends from time t7, the operation mode of the control unit 111 is switched from the signal processing mode to the sleep mode at time t8. In this case, the operation clock of the control unit 111 is switched from 16 MHz to 32 KHz. Then, the elapse of a predetermined time in the sleep mode is determined again.

  As is apparent from FIG. 5, the predetermined time in ST303 and the predetermined time in ST306 are different, and the length thereof is determined as appropriate.

  Thus, in receiving apparatus 100 according to the present embodiment, three types of operation modes are prepared: a sleep mode, a signal determination mode, and a signal processing mode, which have different power consumption. Then, when monitoring the reception of the radio signal from the remote controller 200, it stands by in the sleep mode with the lowest power consumption. In this sleep mode, the radio signal reception determination is performed by shifting to the signal determination mode with the lowest power consumption after the sleep mode every predetermined time. When a radio signal is detected in this signal determination mode, the mode shifts to the signal processing mode with the largest power consumption. On the other hand, when the radio signal is not detected, the mode shifts again to the sleep mode.

  As described above, according to receiving apparatus 100 according to the present embodiment, a signal determination mode having power consumption between the sleep mode and the signal processing mode is provided, and a radio signal is received from remote controller 200 in this signal determination mode. And switching to the sleep mode or the signal processing mode. As a result, it is possible to reduce power consumption when no radio signal is detected compared to a conventional in-vehicle signal receiving device that switches operation clocks in two stages, and thus it is possible to reduce power consumption as a whole device. It has become.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  For example, in the receiving apparatus 100 according to the above-described embodiment, a case where a radio signal from the remote controller 200 is received by switching between three types of operation modes, that is, a sleep mode, a signal determination mode, and a signal processing mode is shown. The type of mode is not limited to this, and can be changed as appropriate. For example, four or more types of operation modes may be prepared to reduce power consumption in the apparatus main body.

It is a functional block diagram which shows the structure of the vehicle-mounted signal receiver which concerns on one embodiment of this invention. It is a functional block diagram which shows the structure of the remote control which transmits a radio signal to the vehicle-mounted signal receiver which concerns on the said embodiment. It is a flowchart for demonstrating the process at the time of receiving the radio signal from a remote control in the vehicle-mounted signal receiver which concerns on the said embodiment. It is a transition state figure of the operation mode in the in-vehicle signal receiving device concerning the above-mentioned embodiment. It is a time chart for demonstrating transfer of the operation clock of ECU in the vehicle-mounted signal receiver which concerns on the said embodiment.

Explanation of symbols

100 In-vehicle signal receiver (receiver)
101 ECU
102 Reception Circuit 103 First Clock 104 Second Clock 109 Reception Determination Unit 110 Clock Control Unit 111 Control Unit 200 Remote Controller (Remote Control)

Claims (5)

  An in-vehicle signal receiving device that receives a radio signal output from a portable communication device carried by an operator, the receiving unit receiving the radio signal, and receiving the radio signal executed at a first operating frequency A first operating mode to wait, a second operating mode executed at a second operating frequency higher than the first operating frequency and receiving the radio signal, and between the first and second operating frequencies A vehicle-mounted signal receiving apparatus comprising: a control unit that executes a third operation mode that is executed at an operating frequency and that determines reception of the wireless signal.   The control unit shifts to the third operation mode at predetermined time intervals in the first operation mode, and detects the reception of the radio signal in the third operation mode. 2. The in-vehicle signal receiving apparatus according to claim 1, wherein when the reception of the wireless signal is not detected, the operation mode is shifted to the first operation mode.   The in-vehicle signal reception according to claim 1, wherein the control unit shifts to the first operation mode after completing the reception processing of the radio signal in the second operation mode. apparatus.   A first operation mode that is executed at a first operating frequency and waits for reception of a radio signal output from a portable communication device carried by an operator, and that is executed at a second operating frequency that is higher than the first operating frequency. The radio signal is switched by switching a second operation mode for receiving the radio signal and a third operation mode that is executed at an operation frequency between the first and second operation frequencies and that determines reception of the radio signal. In the first operation mode, when the reception of the radio signal is detected in the third operation mode. A signal receiving method comprising: shifting to the second operation mode, and shifting to the first operation mode when reception of the wireless signal is not detected.   5. The signal receiving method according to claim 4, wherein after the reception processing of the radio signal is completed in the second operation mode, the mode is shifted to the first operation mode.

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