JP6830802B2 - Wireless system and receiving circuit - Google Patents

Description

The present invention relates to wireless systems and receiving circuits.

Conventionally, in a vehicle, a wireless system that receives a wireless signal transmitted from a wireless key (also called an electronic key) and collates the key has been adopted. The wireless system includes, for example, a remote keyless entry (RKE) system that locks and unlocks the door with a wireless key, and a button provided on the vehicle that locks and unlocks the door and starts the engine without using a wireless key. A smart key entry (SMK) system, a tire pressure monitoring (TPMS) system that monitors tire pressure and activates an alarm when depressurized is incorporated (see, for example, Patent Document 1).

In RKE, SMK, and TPMS, the radio signal transmitted from the wireless key has different characteristics. Therefore, it is necessary to optimize the wireless signal receiving method or the state of the receiving circuit for each system.

The wireless system includes the above-mentioned receiving circuit and a control circuit for controlling the receiving circuit, and these two circuits are connected by a plurality of wires (referred to as harnesses). As a harness, a power supply line for supplying a power supply voltage, a GND line for connecting to a reference potential (for example, a ground potential), a data line for transmitting a data signal from a receiving circuit to a control circuit, and a receiving circuit from a control circuit. A control line or the like for transmitting a control signal for switching the reception state is required. Here, the receiving circuit is installed near the rear window where the radio signal is easily received, for example, and the control circuit is installed near the dashboard, for example. Therefore, a harness having a relatively long length of, for example, 5 m is required to connect the two circuits.
Patent Document 1 Japanese Patent Application Laid-Open No. 2012-148646

However, when a large number of long harnesses are used in a wireless system, the weight of the harness affects the fuel efficiency of the vehicle.

In the first aspect of the present invention, a receiving unit having a receiving circuit for outputting a data signal corresponding to a wireless signal from a wireless key from a data output terminal and a data signal from the data output terminal are input from the data input terminal. At least one that connects a control unit having a control circuit, a data output terminal of the receiving circuit, a power supply terminal and a ground terminal of the receiving unit, a data input terminal of the control circuit, and a power supply terminal and a ground terminal of the control unit, respectively. A wireless system with a harness is provided.

In the second aspect of the present invention, a data output terminal that outputs a data signal corresponding to a wireless signal from the wireless key, a poll timer that specifies a polling period for polling the first wireless signal from the wireless key, and a poll timer. The reception process of the second radio signal from the wireless key is performed during the first predetermined period according to the start of power supply, and the first radio signal is processed during the polling period after the first period. A reception circuit including a radio signal processing unit that performs reception processing of the above is provided.

The outline of the above invention does not list all the features of the present invention. Sub-combinations of these feature groups can also be inventions.

The configuration of the wireless system according to this embodiment is shown. Indicates switching of reception status in a wireless system. An example of the reception operation of the RKE signal in the wireless system is shown. An example of SMK signal reception operation in a wireless system is shown. An example of the reception operation of the TPMS signal in the wireless system is shown.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the inventions claimed in the claims. Also, not all combinations of features described in the embodiments are essential to the means of solving the invention.

FIG. 1 shows the configuration of the wireless system 100 according to the present embodiment. The wireless system 100 connects a control circuit to a receiving circuit using a small number of harnesses, and controls switching of the state (that is, receiving state) of the receiving circuit in each of RKE, SMK, and TPMS by the control circuit. It is a system that enables. Here, the radio signals (also referred to as RKE signal, SMK signal, and TPMS signal, respectively) transmitted from the wireless key in RKE, SMK, and TPMS have different characteristics. Here, the RKE signal is a signal for remotely operating the vehicle such as locking and unlocking the door, and the SMK signal is, for example, locking and unlocking the door by a button provided on the outer surface of the vehicle and inside the vehicle. The TPMS signal is a signal for operating the vehicle such as starting the engine with a button provided on the vehicle, and the TPMS signal is a signal for transmitting the state of the vehicle monitored during the operation of the vehicle such as the tire pressure. Accordingly, in the present embodiment, the radio signal reception method and reception state are optimized for each system.

For example, in RKE, the timing at which the RKE signal is transmitted is when the wireless key is operated when the vehicle is stopped, and the wireless system 100 cannot determine the timing at which the signal is received. Here, if the receiving circuit that receives the signal is always on, the battery is wasted. Therefore, as a method of receiving the RKE signal, a polling standby (also called a polling operation) is adopted in which the receiving circuit is periodically switched (on / off) between the on state and the off state. Further, the RKE signal is transmitted a plurality of times in a relatively narrow reception band with a relatively long signal length of 400 to 800 ms and a low data rate (for example, ~ 3 kbps) in order to give priority to reception sensitivity. As will be described later, the receiving circuit is turned on and off by turning on and off the power supply voltage supplied from the power supply circuit.

In SMK, the timing at which the SMK signal is transmitted is when a button provided on the outer surface of the vehicle is operated, when the foot brake is operated, when the engine start button is operated, and the like. When the control circuit is notified that these operations have been performed, the control circuit causes the wireless key to transmit a SMK signal by transmitting a low frequency (LF) signal to the wireless key by the LF driver. That is, the wireless system 100 can know the timing of receiving the signal. Therefore, as a method of receiving SMK signals, a method of turning on the receiving circuit (event standby) only when some event occurs is adopted, and the radio signal has a relatively short signal length of 100 in order to prioritize the response speed. It is transmitted only once at ~ 200 ms and moderate data rates (eg ~ 8 kbps). For example, since the door is locked and unlocked not only by SMK but also by RKE, the SMK signal and the RKE signal are waiting in parallel.

In the TPMS, the timing at which the TPMS signal is transmitted is an arbitrary timing during traveling. A TPMS signal including air pressure information is randomly transmitted from a barometric pressure sensor provided inside each of a plurality of (for example, four) tires, for example, at a frequency of several times per minute. Therefore, in the wireless system 100, it is not possible to determine the timing of receiving the signal. However, there is no need to save power while driving. Therefore, as a method of receiving the TPMS signal, a method of always turning on the receiving circuit (continuous standby) is adopted, and the wireless signal is transmitted for a short time in a relatively wide reception band with a signal length of about 10 ms and high data. It is transmitted only once at a rate (eg, 10 kbps). Since it is necessary to receive the SMK signal while the engine is starting, the TPMS signal and the SMK signal are waiting in parallel.

Note that different radio frequencies, different frequency bandwidths, different transmission rates, or different transmission methods may be assigned to at least two of the RKE signal, SMK signal, and TPMS signal. Differences in transmission methods include, for example, differences in modulation / demodulation methods such as amplitude modulation (ASK), phase modulation (PSK), frequency modulation (FSK), code division multiple access (CDMA), and time division multiple access (TDMA). There are differences in packet formats, error correction methods, etc.

The wireless system 100 includes a receiving unit 20, a control unit 40, and at least one harness 51 to 53.

The receiving unit 20 is a unit that processes a radio signal emitted from a wireless key (not shown) and outputs it to the control unit 40, and includes an antenna 1, a receiving circuit 21, and an output buffer 6. The receiving circuit 21 has terminals for inputting / outputting various signals, that is, a signal terminal 11, a power supply terminal 12, a control input terminal 13, a data output terminal 14, and a ground terminal 15.

The antenna 1 is an element that receives a radio signal (for example, a radio frequency (RF) signal) emitted from a wireless key (not shown). The antenna 1 is connected to the signal terminal 11 and transmits the radio signal (signal S1) received via the signal terminal 11 to the RF signal processing unit 2 of the receiving circuit 21.

The receiving circuit 21 is a circuit that outputs a data signal corresponding to a radio signal from a wireless key (not shown) from the data output terminal 14, and is an RF signal processing unit 2, a signal detection circuit 3, a demodulator circuit 4, and an AND logic gate. 5. NOR logic gate 7, continuous reception timer 8, polling timer 9, and control circuit 10 are included.

The RF signal processing unit 2 converts the radio signal (signal S1) received by the antenna 1 into an intermediate frequency (IF) signal and transmits it as an input signal (signal S2) to the signal detection circuit 3 and the demodulation circuit 4 described later. ..

The signal detection circuit 3 is a circuit that outputs a signal detection flag (signal S3) of “Hi” when the strength of the input signal (signal S2) exceeds the threshold value and “Low” when the strength does not exceed the threshold value. The threshold value may be set in advance to an appropriate level for extracting an effective signal from the noise included in the input signal, for example. Further, it may be set to an appropriate level for each of RKE, SMK, and TPMS. The signal detection flag (signal S3) is transmitted to the AND logic gate 5 and the NOR logic gate 7, which will be described later.

The demodulation circuit 4 is an example of a radio signal processing unit that processes a radio signal by demodulating the input signal (signal S2). As will be described later, the demodulation circuit 4 receives and processes the RKE signal during the polling period (or RKE reception period), and in response to the start of power supply from the control unit 40, the demodulation circuit 4 has a predetermined SMK reception period. During that time, the SMK signal is received and processed, and in response to the control signal (signal S23) being input from the control circuit 42 from the control input terminal 13, the TPMS signal reception processing is performed during a predetermined TPMS reception period. Do. The demodulation circuit 4 can select and receive only one of the RKE signal, the SMK signal, and the TPMS signal by the operation of the control circuit 10 described later. As a result, the demodulation circuit 4 can be shared for receiving the RKE signal, the SMK signal, and the TPMS signal, including a part of each component of the receiving circuit 21, and the power consumption can be reduced, the resources can be reduced, and the like. Becomes possible. The demodulated data (signal S4) is transmitted to the AND logic gate 5.

The AND logic gate 5 calculates the logical product of the input signal detection flag (signal S3) and demodulation data (signal S4), and outputs the demodulated data as a data signal (data signal) only when the result, that is, the signal detection flag is "Hi". It is output as a signal S5) to the outside of the receiving circuit 21 via the data output terminal 14.

The NOR logic gate 7 calculates the NOR of the control signal (signal S23) input from the outside via the control input terminal 13 and the signal detection flag (signal S3) transmitted from the signal detection circuit 3, and the result is the result. Is transmitted to the continuous reception timer 8 as a signal S7. Here, the signal S7 is a control signal (signal S23) including an off signal from the outside when the signal detection flag (signal S3) is "Low", that is, when the radio signal is not received. Turns on signal.

The continuous reception timer 8 is a timer that counts the time for receiving the TPMS signal in the TPMS. The timer is started in response to the rise of the input signal S7, and the timer is started until the predetermined TPMS reception time expires. The continuous reception timer output (signal S8) including the on signal is transmitted to the control circuit 10.

The polling timer 9 is a timer for the receiving circuit 21 to autonomously perform a polling operation (also called a self-polling operation) in RKE, and is a polling timer output (signal S9) that repeats an on-signal during the RKE reception period in the polling cycle. Is generated and input to the control circuit 10. As a result, the polling timer 9 specifies a polling period for polling the RKE signal from the wireless key (not shown). The polling cycle and the RKE reception period may be fixed values set in advance, or may be stored in a non-volatile memory (not shown) such as EEPROM, and these settings may be read when the power of the reception circuit 21 is turned on.

The control circuit 10 controls the receiving circuit 21 to a receiving state optimized for receiving the RKE signal, SMK signal, or TPMS signal (referred to as RKE receiving state, SMK receiving state, or TPMS receiving state, respectively). It is a circuit to do. Here, the control circuit 10 is triggered by receiving the polling timer output (signal S9) to put the reception circuit 21 in the RKE reception state during the RKE reception period. Further, the control circuit 10 is triggered by receiving a power supply signal (signal S22), which will be described later, that is, when the power supply is once turned off and then turned on again, and the receiving circuit 21 receives SMK during the SMK reception period. Put it in a state. Further, the control circuit 10 is triggered by receiving the continuous reception timer output (signal S8) to put the reception circuit 21 in the TPMS reception state during the TPMS reception period. The SMK reception period and the TPMS reception period may be fixed values set in advance, or may be stored in a non-volatile memory (not shown) such as EEPROM and read these settings when the power of the reception circuit 21 is turned on.

As described above, the receiving circuit 21 performs a polling operation by itself by the polling timer 9 and the control circuit 10, so that the control circuit 42 in the control unit 40 that processes the data signal is a SMK signal, a TPMS signal, or the like. It is only necessary to operate when the desired wave of is received, and it is possible to reduce the power consumption.

As described above, the receiving circuit 21 has a signal terminal 11, a power supply terminal 12, a control input terminal 13, a data output terminal 14, and a ground terminal 15. The signal terminal 11 is connected to the antenna 1, and the receiving circuit 21 receives the radio signal (signal S1) received from the antenna 1 via the signal terminal 11. The power supply terminal 12 is connected to the power supply circuit 41 in the control unit 40 via the power supply line L1, and the receiving circuit 21 transmits the power supply voltage VDD and its on / off power supply signal (signal S22) from the power supply circuit 41 via the power supply circuit 41. ) Is received. The control input terminal 13 is a terminal for inputting a control signal (signal S23) from the control circuit 42, is connected to the pull-up resistor R in the control unit 40 via the data line L2, and the receiving circuit 21 is connected to this terminal. The control signal (signal S23) is received via. The data output terminal 14 is connected to the output buffer 6 as described later. The ground terminal 15 is connected to the reference potential VSS and is also connected to the ground terminal 37 of the control circuit 42 via the GND line L3.

The output buffer 6 is connected between the data line L2 (that is, a common signal line described later), the data output terminal 14, and the low potential reference potential VSS, and is a data signal (signal S5) input from the data output terminal 14. This is a data switch for switching whether or not to connect the data line L2 to the reference potential VSS according to the above. The voltage format data signal (signal S5) input from the data output terminal 14 by the output buffer 6 is converted into a current format data signal (signal S6) and transmitted to the control unit 40 via the data line L2. .. As the output buffer 6, for example, a transistor in which the collector, the base, and the emitter are connected to the data line L2, the data output terminal 14, and the reference potential VSS can be used.

The control unit 40 is a unit that processes the data signal (signal S6) transmitted from the receiving circuit 21 and controls the receiving state of the receiving circuit 21, and is a pull-up resistor R, a switch element 22, a switch element 23, and a power supply circuit. 41 and a control circuit 42 are included. The power supply circuit 41 has power supply terminals 31 and 32 for outputting the power supply voltage VDD. The control circuit 42 has terminals for inputting and outputting various signals, that is, a power supply terminal 33, a power supply control terminal 34, a data input terminal 35, a control output terminal 36, and a ground terminal 37.

The pull-up resistor R is a resistance element for converting a current-type data signal (signal S6) transmitted from the receiving circuit 21 via the data line L2 into a voltage-type signal, and one end thereof is the data line L2 (that is, the data line L2). , A common signal line described later), and the other end is connected to a high voltage source (providing a high potential reference potential). As a result, the potential of the data line L2 becomes "Hi". The data signal converted into the voltage format is transmitted to the control circuit 42.

The switch element 22 is an element that connects and disconnects the power supply line L1 connecting the power supply terminal 31 of the power supply circuit 41 and the power supply terminal 12 of the reception circuit 21, one end to the power supply line L1 and the other end to the power supply terminal 31. It is connected. A power supply signal (signal S22) is generated by disconnecting the power supply line L1 in response to the power supply control signal (signal S34) output from the control circuit 42 via the power supply control terminal 34 by the switch element 22, and this is used as the power supply line. By transmitting to the receiving circuit 21 via L1 (that is, by starting the power supply), SMK reception by the receiving circuit 21 is triggered.

The switch element 23 is a control switch for switching the potential of the data line L2 between “Hi” and “Low”, and one end is the data line L2 (that is, a common signal line described later) and the other end is a low potential. It is connected to the reference potential VSS of. It is turned on (closes the switch) according to the control output signal (signal S36) output from the control circuit 42 via the control output terminal 36 by the switch element 23, and the data line L2 is connected to the reference potential VSS to control the potential. A control signal (signal S23) is generated by dropping from "Hi" to "Low", and this is sent to the receiving circuit 21 via the data line L2 (also called a control line when transmitting the control signal (signal S23)). By transmitting, the TPMS reception by the receiving circuit 21 is triggered.

The power supply circuit 41 is a circuit that supplies the power supply voltage VDD to the reception circuit 21 in the control circuit 42 and the reception unit 20. The power supply circuit 41 has two power supply terminals 31 and 32 as described above, the power supply terminal 31 is connected to the power supply terminal 12 of the receiving circuit 21 via the switch element 22 and the power supply line L1, and the power supply terminal 32 is the control circuit 42. It is connected to the power supply terminal 33 of. As the power supply voltage VDD, for example, a 5V voltage can be used.

The control circuit 42 is a circuit that inputs and processes a data signal from the data output terminal 14 from the data input terminal 35. As described above, the control circuit 42 has a power supply terminal 33, a power supply control terminal 34, a data input terminal 35, a control output terminal 36, and a ground terminal 37. The power supply terminal 33 is connected to the power supply terminal 32 of the power supply circuit 41, and the control circuit 42 receives the power supply voltage VDD from the power supply circuit 41 via this. The power supply control terminal 34 is connected to the switch element 22, and the control circuit 42 transmits a power supply control signal (signal S34) to the switch element 22 via this and operates the power supply signal (signal S22) to operate the receiving circuit. Trigger SMK reception by 21. The data input terminal 35 is connected to the output buffer 6 and the control input terminal 13 of the receiving circuit 21 via the data line L2 (control line), and the control circuit 42 receives a data signal (data signal) from the receiving circuit 21 via the output buffer 6. Along with receiving the signal S6), the control signal (signal S23) is transmitted to the receiving circuit 21 via the control input terminal 13. The control output terminal 36 is a terminal for controlling the receiving circuit 21, and is connected to the switch element 23. The control circuit 42 transmits a control output signal (signal S36) to the switch element 23 via the control output terminal 36 for control. By generating a signal (signal S23), TPMS reception by the receiving circuit 21 is triggered. The ground terminal 37 is connected to the reference potential VSS and is also connected to the ground terminal 15 of the receiving circuit 21 via the GND line L3.

At least one harness 51 to 53 is a line connecting the receiving circuit 21 in the receiving unit 20 and the power supply circuit 41 and the control circuit 42 in the control unit 40, and includes three harnesses 51 to 53 in this embodiment. .. The harness 51 connects the power supply terminal 12 of the receiving circuit 21 (or receiving unit 20) and the power supply terminal 31 of the power supply circuit 41 (or control unit 40) via the switch element 22 in the control unit 40, and connects the power supply voltage. It functions as a power supply line L1 for transmitting VDD and its on / off power supply signal (signal S22). The harness 52 connects the data output terminal 14 of the receiving circuit 21 and the data input terminal 35 of the control circuit 42 via the output buffer 6, and transmits a data signal (signal S6) from the data output terminal 14 to the data input terminal 35. It functions as a control line that transmits a control signal (signal S23) from the control output terminal 36 of the control circuit 42 to the control input terminal 13 of the reception circuit 21 via the data line L2 and the switch element 23 to be transmitted, that is, for both transmissions. It functions as a common signal line that is commonly used. The harness 53 connects the ground terminal 15 of the receiving circuit 21 (or the receiving unit 20) and the ground terminal 37 of the control circuit 42 (or the control unit 40), and functions as a GND line L3 sharing the reference potential VSS.

In the wireless system 100 having the above configuration, the data line L2 (that is, the harness 52) that transmits the data signal (signal S6) output from the receiving circuit 21 to the control circuit 42 is transmitted to the control signal (that is, the harness 52) that is output from the control circuit 42. The signal S23) is shared as a control line for transmitting to the receiving circuit 21. As a result, the control circuit 42 is connected to the reception circuit 21 using the three harnesses 51 to 53, and the control circuit 42 controls the switching of the reception state of the reception circuit 21 for each of the RKE, SMK, and TPMS. It becomes possible.

FIG. 2 shows switching of the reception state of the reception circuit 21 in the wireless system 100.

The reception state of the reception circuit 21 suitable for receiving the RKE signal is switched by the polling operation by the polling timer 9 and the control circuit 10 in the reception circuit 21. The polling timer 9 generates a polling timer output (signal S9) that repeats the on-signal during the RKE reception period in a predetermined polling cycle, and inputs the polling timer output (signal S9) to the control circuit 10. As a result, the control circuit 10 sets the demodulation circuit 4 (that is, the radio signal processing unit) to a state suitable for receiving the RKE signal (“RKE reception ON” state in the figure) during the RKE reception period.

The switching of the reception state of the reception circuit 21 suitable for receiving the SMK signal is performed by inputting the power supply signal (signal S22) to the reception circuit 21. For example, when a button provided on the vehicle such as a door lever is pressed during the polling operation and the control circuit 42 is notified that this operation has been performed, the control circuit 42 temporarily disconnects the power supply line L1. A signal (signal S34) is transmitted from the power supply control terminal 34 to the switch element 22. As a result, the power signal (signal S22) in the temporarily off state is transmitted to the receiving circuit 21 via the power line L1, the receiving circuit 21 is temporarily turned off, and the power is turned on again. That is, the power supply to the receiving circuit 21 is started in response to an instruction from the outside. At the same time, the control circuit 42 wirelessly instructs the wireless key (not shown) to transmit the SMK signal. While the power signal (signal S22) in the off state is being input, the receiving circuit 21, that is, the polling timer 9 is turned off, so that the polling operation is stopped. The control circuit 10 puts the demodulation circuit 4 (that is, the radio signal processing unit) in a state suitable for receiving the SMK signal (“SMK reception ON” state in the figure) during the SMK reception period immediately after the power is turned on. Set.

The switching of the reception state of the reception circuit 21 suitable for receiving the TPMS signal is performed by inputting the control signal (signal S23) to the reception circuit 21. The control circuit 42 transmits a control output signal (signal S36) including an off signal from the control output terminal 36 while receiving the data signal (signal S6) from the receiving circuit 21 and not transmitting the control signal to the receiving circuit 21. It is transmitted to the switch element 23 to open the switch element 23. At this time, the potential of the data line L2 maintains the “Hi” state. Here, for example, when the engine is started during the polling operation and the control circuit 42 is notified that this operation has occurred, the control circuit 42 temporarily sets the control line (that is, the data line L2) to the reference potential VSS. The control output signal (signal S36) connected to is transmitted from the control output terminal 36 to the switch element 23. By temporarily connecting the control line to the reference potential VSS by the switch element 23, a temporary “Low” state control signal (signal S23) is transmitted to the receiving circuit 21 via the control line.

On the other hand, in the receiving circuit 21, the negative logic sum of the control signal (signal S23) input by the NOR logic gate 7 via the control input terminal 13 and the signal detection flag (signal S3) output from the signal detection circuit 3 is obtained. The calculation is performed, and the result (signal S7) is input to the continuous reception timer 8. Therefore, when the receiving circuit 21 is outputting the data signal (signal S6), the signal detection flag (signal S3) is in the “Hi” state, so that the control input terminal 13 is cut off by the NOR logic gate 7. That is, the receiving circuit 21 cuts off the input of the control signal (signal S23). When the receiving circuit 21 does not output the data signal (signal S5), the signal detection flag (signal S3) is in the “Low” state, so that the NOR logic gate 7 opens the control input terminal 13. That is, the reception circuit 21 receives the input of the control signal (signal S23), and the control signal (signal S23) in the “Low” state is input via the control input terminal 13, so that the continuous reception timer 8 is turned on (signal S23). The signal S7) is transmitted. When the continuous reception timer 8 detects the rising edge of the signal S7, that is, the falling edge of the control signal (signal S23), the continuous reception timer 8 outputs the continuous reception timer output (signal S8) including the on signal until the TPMS reception time expires. It is transmitted to the control circuit 10. As a result, the control circuit 10 sets the demodulation circuit 4 (that is, the radio signal processing unit) to a state suitable for receiving the TPMS signal (“TPMS reception ON” state in the figure) during the TPMS reception period.

In order to avoid collision between the data signal (signal S6) from the reception circuit 21 and the control signal (signal S23) from the control circuit 42, the continuous reception timer 8 detects the edge of the control signal (signal S23). The pulse signal should be wide enough for.

As a result, the harness 52 is used as the data line L2 for transmitting the data signal (signal S6) output from the receiving circuit 21 to the control circuit 42, and the control signal (signal S23) output from the control circuit 42. Can be used as a control line for transmitting to the receiving circuit 21.

FIG. 3 shows an example of the RKE signal reception operation in the wireless system 100. As described above, the demodulation circuit 4 (that is, the radio signal processing unit) is set to the "RKE reception ON" state suitable for receiving the RKE signal by the polling operation by the polling timer 9 and the control circuit 10 in the receiving circuit 21. To. In the RKE reception ON state, when the signal detection circuit 3 detects the RKE signal included in the radio signal (signal S1), the demodulation circuit 4 starts demodulation at the same time as the detection, and the data signal (signal S6) is output. .. The RKE reception ON state is extended while the RKE signal is being detected, and ends when the RKE signal is interrupted. Note that the control circuit 10 detects the RKE signal during the polling period, but cannot receive at least a part of the transmission contents. Therefore, even after the polling period, for example, until all the transmission contents are received, the RKE signal is received. The reception ON state may be continued to continue the reception processing of the RKE signal. When the RKE reception ON state ends, the reception circuit 21 transitions to the off state, and then repeats the on state by the polling operation.

FIG. 4 shows an example of SMK signal reception operation in the wireless system 100. As described above, the button provided on the vehicle is pressed, a power signal (signal S22) in a temporarily off state is transmitted with this operation, and the receiving circuit 21 is temporarily turned off. The demodulation circuit 4 (that is, the radio signal processing unit) is set to the SMK reception ON state suitable for receiving the SMK signal during the SMK reception period immediately after the reception circuit 21 is turned on. In the SMK reception ON state, the signal detection circuit 3 waits for the SMK signal to be transmitted from the wireless key (not shown), and when the signal detection circuit 3 detects the SMK signal included in the wireless signal (signal S1), the demodulation circuit is detected at the same time. Demodulation by 4 is started, and a data signal (signal S6) is output. The SMK reception ON state ends when the SMK reception period elapses. However, the SMK reception ON state is extended while the SMK signal is still detected even after the SMK reception period has elapsed, and ends when the SMK signal is interrupted. When the SMK reception ON state ends, the reception circuit 21 transitions to the OFF state, and then the RKE reception ON state is repeated by the polling operation.

FIG. 5 shows an example of a TPMS signal reception operation in the wireless system 100. As described above, by transmitting the control signal (signal S23) including the off signal from the control circuit 42 to the receiving circuit 21, the demodulation circuit 4 (that is, the radio signal processing unit) is suitable for receiving the TPMS signal. The reception is set to the ON state. In the TPMS reception ON state, it waits for the TPMS signal to be transmitted from the pressure sensor provided inside the tire, and when the signal detection circuit 3 detects the TPMS signal included in the radio signal (signal S1), it is detected at the same time. Demodulation by the demodulation circuit 4 is started, and a data signal (signal S6) is output. When the TPMS signal is interrupted, the output of the data signal (signal S6) is stopped, but the TPMS reception ON state is maintained until the TPMS reception period elapses. When the TPMS reception ON state ends, the reception circuit 21 transitions to the OFF state, and then the RKE reception ON state is repeated by the polling operation. When the TPMS reception ON state is continued, the control circuit 42 transmits the control signal (signal S23) to the reception circuit 21 again in the same manner as before.

If, for example, the engine is stopped while the TPMS reception ON state continues, the control circuit 42 transmits a power supply signal (signal S22) including an off signal to the reception circuit 21 via the power supply line L1 as before. Then, by temporarily turning off the power of the receiving circuit 21, the TPMS reception ON state is forcibly terminated. Further, when SMK reception is started while the TPMS reception ON state is continuing, the power of the reception circuit 21 is also temporarily turned off.

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various changes or improvements can be made to the above embodiments. It is clear from the description of the claims that such modified or improved forms may also be included in the technical scope of the present invention.

The order of execution of operations, procedures, steps, steps, etc. in the devices, systems, programs, and methods shown in the claims, specification, and drawings is particularly "before" and "prior to". It should be noted that it can be realized in any order unless the output of the previous process is used in the subsequent process. Even if the scope of claims, the specification, and the operation flow in the drawings are explained using "first", "next", etc. for convenience, it means that it is essential to carry out in this order. It's not a thing.

1 ... antenna, 2 ... RF signal processing unit, 3 ... signal detection circuit, 4 ... demodulation circuit, 5 ... AND logic gate, 6 ... output buffer, 7 ... NOR logic gate, 8 ... continuous reception timer, 9 ... polling timer, 10 ... control circuit, 11 ... signal terminal, 12 ... power supply terminal, 13 ... control input terminal, 14 ... data output terminal, 15 ... ground terminal, 20 ... reception unit, 21 ... reception circuit, 22 ... switch element, 23 ... switch Element, 31 ... power supply terminal, 32 ... power supply terminal, 33 ... power supply terminal, 34 ... power supply control terminal, 35 ... data input terminal, 36 ... control output terminal, 37 ... ground terminal, 40 ... control unit, 41 ... power supply circuit, 42 ... control circuit, 51 ... harness, 52 ... harness, 53 ... harness, 100 ... wireless system, L1 ... power supply line, L2 ... data line, L3 ... GND line.

Claims (17)

A receiving unit having a receiving circuit that outputs a data signal corresponding to a wireless signal from a wireless key from a data output terminal, and a receiving unit.
A control unit having a control circuit for inputting a data signal from the data output terminal from the data input terminal, and
At least one harness connecting the data output terminal of the receiving circuit, the power supply terminal and the ground terminal of the receiving unit, the data input terminal of the control circuit, and the power supply terminal and the ground terminal of the control unit, respectively. ,
Equipped with a,
The control circuit has a control output terminal for controlling the receiving circuit.
The receiving circuit has a control input terminal for inputting a control signal from the control circuit.
The at least one harness has a common signal line commonly used for transmitting a data signal from the data output terminal to the data input terminal and transmitting a control signal from the control output terminal to the control input terminal. ,
The receiving circuit is predetermined according to the detection that the power supply is stopped and the power supply is started again from the state where the power supply is stopped from the power supply terminal of the control unit via the at least one harness. A wireless system that performs reception processing of a second radio signal during the first period . The receiving circuit
A polling timer that specifies a polling period for polling the first wireless signal from the wireless key, and
The wireless system according to claim 1, further comprising a wireless signal processing unit that performs reception processing of the first wireless signal during the polling period. The radio signal processing unit detects the first radio signal during the polling period, but cannot receive at least a part of the transmission content, so that the first radio signal is also after the polling period. The wireless system according to claim 2, wherein the reception process of the above is continued. Wherein the control circuit, the timing of receiving the second non-linear signal from the receiving circuit the wireless key, the power supply from the power supply terminal of the control unit to the receiving unit via the at least one harness The wireless system according to claim 2 or 3. The control circuit stops and resupplys the power supply to the receiving unit in response to an instruction from the outside, and wirelessly instructs the wireless key to transmit the second radio signal. Item 4. The wireless system according to item 4. The control unit
A resistor provided between the common signal line and the first reference potential,
A control switch that switches whether or not to connect the common signal line to the second reference potential according to the control signal from the control output terminal.
Have,
Any one of claims 2 to 5, wherein the receiving unit has a data switch for switching whether or not to connect the common signal line to the second reference potential according to the data signal from the data output terminal. The wireless system described in. The control circuit outputs the first control signal instructing to perform reception processing of the third radio signal from a transmitter different from the wireless key from the control output terminal.
The item according to any one of claims 2 to 6 , wherein the radio signal processing unit performs reception processing of the third radio signal in response to the input of the first control signal from the control input terminal. Wireless system. The claim that the radio signal processing unit performs reception processing of the third radio signal for a predetermined second period in response to the input of the first control signal from the control input terminal. 7. The wireless system according to 7 . At least two of the first radio signal, the second radio signal, and the third radio signal are claimed to differ in at least one of radio frequency, frequency bandwidth, transmission rate, and transmission method. Item 7. The wireless system according to item 7 or 8 . Any one of claims 7 to 9 , wherein the radio signal processing unit can select and receive only one of the first radio signal, the second radio signal, and the third radio signal. The wireless system described in the section. The first wireless signal is a signal for remotely operating the vehicle.
The second radio signal is a signal for operating the vehicle in response to the operation of a button provided on the outer surface of the vehicle.
The wireless system according to any one of claims 7 to 10 , wherein the third wireless signal is a signal for transmitting the state of the vehicle monitored during the operation of the vehicle. A data output terminal that outputs a data signal according to the wireless signal from the wireless key,
A polling timer that specifies a polling period for polling the first wireless signal from the wireless key, and
The second wireless signal from the wireless key is received from the wireless key for a predetermined first period according to the fact that the power supply is stopped from the state in which the power is being supplied and the power supply is restarted . A radio signal processing unit that performs reception processing of the first radio signal during the polling period after the first period, and
A control input terminal that receives a control signal from the control circuit and is connected to a common signal line that is also used to transmit the data signal from the data output terminal to the control circuit.
Receiving circuit with. When the radio signal processing unit detects the first radio signal during the polling period but cannot receive at least a part of the transmission contents, the radio signal processing unit receives the first radio signal even after the polling period. receiving circuit according to claim 1 2 to continue. The control input terminal is connected to a common signal line connected to the first reference potential via a resistor.
The data output terminal in response to said data signal, said common signal line and the receiving circuit according to claim 1 3 for switching the connection state of the data switch provided between the second reference potential. The radio signal processing unit responds to the fact that the first control signal instructing the reception processing of the third radio signal from a transmitter different from the wireless key is input from the control input terminal. The receiving circuit according to any one of claims 12 to 14 , wherein the receiving process of the third radio signal is performed . The claim that the radio signal processing unit performs reception processing of the third radio signal for a predetermined second period in response to the input of the first control signal from the control input terminal. The receiving circuit according to 15 . The 15 or 16 according to claim 15 , wherein the radio signal processing unit can select and receive only one of the first radio signal, the second radio signal, and the third radio signal. Receiving circuit.

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