JP2018038030A - Signal processing device - Google Patents

Abstract

[Problem] To reduce the cost of a signal processing device for a vehicle, etc. [Solution] A signal processing device 100 processes a signal for controlling the start of a power source provided in a target device, and includes a high-frequency receiving unit 20 that receives a high-frequency signal and converts it into an intermediate signal with a lower frequency than the high-frequency signal, a signal processing unit 60 that processes the intermediate signal, and an input switching unit 40 that receives a low-frequency signal with a lower frequency than the high-frequency signal in communication for starting the power source of the target device, and switches between inputting the intermediate signal or the low-frequency signal to the signal processing unit. [Selected Figure] Figure 1

Description

  The present invention relates to a signal processing apparatus.

Conventionally, a signal processing device that is provided in a vehicle or the like and processes a low-frequency signal and a high-frequency signal is known (see, for example, Patent Document 1). For example, when realizing an immobilizer function of a vehicle, the signal processing device performs short-range wireless communication with a user's key terminal using a low-frequency signal. When realizing a keyless entry function or the like, the signal processing device receives a high frequency signal from a key terminal or the like carried by the user.
Patent Document 1 Japanese Patent Application Laid-Open No. 2012-250584

  If the signal processing device is provided with a processing circuit for high-frequency signals and a processing circuit for low-frequency signals, the circuit scale increases.

  In one aspect of the present invention, a signal processing device for processing a signal for controlling the start of a power source provided in a target device is provided. The signal processing device may include a high frequency receiving unit that receives a high frequency signal and converts the high frequency signal into an intermediate signal having a frequency lower than that of the high frequency signal. The signal processing device may include a signal processing unit that processes the intermediate signal. In the communication for authentication when starting the power source of the target device, the signal processing device receives a low frequency signal having a frequency lower than that of the high frequency signal and inputs an intermediate signal to the signal processing unit, or An input switching unit that switches whether to input a low-frequency signal may be provided.

  The signal processing apparatus may include a setting unit that sets at least one of a target frequency or a frequency bandwidth of signal processing in the signal processing unit. The input switching unit, the high frequency receiving unit, and the signal processing unit may be formed on the same chip. You may further provide the signal output part which is provided in the exterior of the chip | tip and outputs the starting signal for starting a power source. An external processing unit that is provided outside the chip and processes a network signal that communicates with a network in the target device may be further provided. The external processing unit may generate a start signal and input it to the signal output unit.

  The external processing unit may generate a data pattern to be transmitted to the outside according to a signal output from the chip and input the data pattern to the signal output unit. The signal output unit may generate a transmission signal corresponding to the data pattern.

  The high frequency signal may be a signal for unlocking a lock provided in the target device. The high frequency signal may be a signal for operating at least one of a lamp and a buzzer provided in the target device. The high-frequency signal may be a signal indicating the measurement result of the air pressure of the tire provided in the target device.

  The above summary of the present invention does not enumerate all of the features of the present invention. A sub-combination of these feature groups can also be an invention.

It is a block diagram which shows the structural example of the signal processing apparatus 100 which concerns on embodiment of this invention. 3 is a diagram illustrating a configuration example of an input switching unit 40, a high frequency receiving unit 20, and a signal processing unit 60. FIG. 1 is a diagram illustrating an example of an overall configuration of a signal processing device 100. FIG. It is a figure which shows the structural example of the control system 200 which controls an object apparatus.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is a block diagram illustrating a configuration example of a signal processing device 100 according to an embodiment of the present invention. The signal processing device 100 controls a low-frequency signal for authentication when starting a power source provided in a target device such as a vehicle and a predetermined component of the target device, or communicates with a predetermined component. The high frequency signal used for the processing is processed.

  The target device of this example is a vehicle, and the signal processing device 100 is mounted on the vehicle. The power source of the target device of this example is a vehicle engine or motor. As an example, the predetermined component of the target device is an air pressure measurement unit that measures the air pressure of a vehicle door lock or a vehicle tire.

  An example of using a low-frequency signal is short-range wireless communication between a key terminal 110 carried by a user and a vehicle-side device. More specifically, there is an immobilizer function in a vehicle that starts a power source by inserting a mechanical key provided in the key terminal 110 into a key cylinder. When the mechanical key is inserted into the key cylinder, the communication unit provided in the key terminal 110 and the signal processing device 100 perform short-range wireless communication with a low-frequency signal. On the condition that the key terminal 110 is authenticated by the communication, the start of the power source of the vehicle is permitted.

  Further, in a vehicle in which the power source is started by pressing the start button in a state where the key terminal 110 is authenticated, when the battery of the key terminal 110 runs out, the key terminal 110 and the device on the vehicle side perform a low frequency signal. Short-distance wireless communication using For example, the key terminal 110 is brought close to a specific part such as a start button, and short-range wireless communication is performed between the key terminal 110 and the vehicle-side device. On the condition that the key terminal 110 is authenticated by the communication, the start of the power source of the vehicle is permitted.

  An example of using a high-frequency signal is a keyless entry function. For example, the key terminal 110 is provided with a button for unlocking and locking the door and trunk of the vehicle. When the user presses the button, the key terminal 110 unlocks or opens the signal processing device 100. A high-frequency signal instructing locking is wirelessly transmitted. On the condition that the key terminal 110 is authenticated by the communication, the door of the vehicle is unlocked or locked.

  As another example of using a high-frequency signal, there is a location notification function that turns on a lamp or sounds a buzzer to notify the location of the vehicle when the user presses a button on the key terminal 110. Also in this case, a radio frequency signal instructing location notification is wirelessly transmitted from the key terminal 110 to the signal processing device 100. On the condition that the key terminal 110 is authenticated by the communication, the lamp and buzzer of the vehicle are controlled.

  As another example of using a high-frequency signal, there is a smart ride function that unlocks a door and a trunk of a vehicle when a user carrying the key terminal 110 approaches the vehicle or contacts a specific place of the vehicle. Also in this case, a high frequency signal instructing unlocking is wirelessly transmitted from the key terminal 110 to the signal processing device 100. On the condition that the key terminal 110 is authenticated by the communication, the door of the vehicle is unlocked. Further, when the start button is pressed while the key terminal 110 is authenticated, the power source is started.

  Another example of using a high-frequency signal is an air pressure measurement function that measures the air pressure of a vehicle tire. Each tire is provided with an air pressure measurement unit, and each air pressure measurement unit wirelessly transmits a high-frequency signal indicating a measurement result of the air pressure of each tire to the signal processing device 100.

  The signal processing apparatus 100 performs processing corresponding to at least one of the above-described keyless entry function, location notification function, smart ride function, and air pressure measurement function as a function that uses a high-frequency signal. The signal processing apparatus 100 may perform processing corresponding to a plurality of functions among the functions described above, or may perform processing corresponding to all functions.

  In this example, the operation of the signal processing apparatus 100 will be described using a keyless entry function or a smart ride function. The signal processing device 100 receives a high frequency signal for opening and closing a lock such as a door of a vehicle from a key terminal 110 carried by a user of the vehicle. The high frequency signal may be set for each key terminal 110 and may include encrypted identification information. The signal processing device 100 authenticates the key terminal 110 based on the identification information included in the high frequency signal. For example, the signal processing apparatus 100 authenticates the key terminal 110 when the identification information matches with preset information. The signal processing apparatus 100 may generate a signal for operating a lock provided on the vehicle on condition that the key terminal 110 is authenticated.

  The high frequency signal may be transmitted from the key terminal 110 when the user operates the key terminal 110. For example, the key terminal 110 is provided with an operation button or the like for unlocking or locking the door lock of the vehicle. In another example, the key terminal 110 may transmit a high-frequency signal when the user carrying the key terminal 110 approaches within a predetermined distance from the vehicle, and the user carrying the key terminal 110 The key terminal 110 may transmit a high-frequency signal when it comes into contact with a predetermined location such as a vehicle door. In this case, the signal processing apparatus 100 may transmit a signal to the key terminal 110 by detecting that the user has touched the vehicle door or the like. When the key terminal 110 receives the signal, the key terminal 110 may transmit a high-frequency signal including identification information. Further, the key terminal 110 transmits a high-frequency signal at a constant cycle, and the signal processing apparatus 100 opens the door when the user contacts the vehicle door or the like with the key terminal 110 being authenticated. May be locked.

  As described above, the signal processing apparatus 100 may receive a high-frequency signal indicating the measurement result of the air pressure from the air pressure measurement unit provided in the vehicle tire. The air pressure measurement unit may be provided for each tire. The signal processing device 100 generates a warning or the like to the user according to the measurement result in the air pressure measurement unit.

  As described above, the high-frequency signal may be a signal for operating at least one of the lamp and the buzzer of the vehicle. In this case, the high frequency signal may be transmitted from the key terminal 110 when the user operates the key terminal 110. The high frequency signal includes identification information of the key terminal 110.

  Next, an example using a low frequency signal will be described. The vehicle is provided with a power source operation unit 120 for starting and stopping a power source such as an engine. The power source operation unit 120 has a key cylinder into which a mechanical key is inserted, for example. In this case, a mechanical key may be provided integrally with the key terminal 110. Near the key cylinder, a short-range wireless communication unit that communicates with the key terminal 110 is provided.

  The short-range wireless communication unit in the key terminal 110 includes an antenna coil that generates a current in accordance with a magnetic field generated by the key cylinder or the like and transmits a signal when the mechanical key is inserted into the key cylinder. Accordingly, communication can be performed between the key terminal 110 and the power source operation unit 120 even when the battery in the key terminal 110 is discharged.

  Further, the power source operation unit 120 may have a start button for starting the power source. Near the start button, a short-range wireless communication unit that communicates with the key terminal 110 is provided. The key terminal 110 is also provided with a short-range wireless communication unit that communicates with a communication unit near the start button. The short-range wireless communication unit in the key terminal 110 includes an antenna coil that generates a current according to the magnetic field generated by the key cylinder or the like when the key terminal 110 approaches the start button and transmits a signal. Accordingly, communication can be performed between the key terminal 110 and the power source operation unit 120 even when the battery is discharged.

  In short-range wireless communication between the key terminal 110 and the power source operation unit 120, a low-frequency signal having a frequency lower than that of a high-frequency signal in communication for controlling the lock is transmitted and received. The high frequency signal may be a megahertz band signal and the low frequency signal may be a kilohertz band signal. However, the frequency of the signal is not limited to this.

  The signal processing device 100 authenticates the key terminal 110 based on the low frequency signal received by the power source operation unit 120. The low frequency signal may be set for each key terminal 110 and may include encrypted identification information. The signal processing apparatus 100 authenticates the key terminal 110 when the identification information matches with preset information. The signal processing device 100 starts the power source of the vehicle on the condition that the key terminal 110 is authenticated and a predetermined operation is performed on the key cylinder or the start button. With such a configuration, it is possible to prevent unauthorized start of the power source of the vehicle.

  The signal processing apparatus 100 of this example includes a high frequency receiving unit 20, a signal processing unit 60, and an input switching unit 40. The high frequency receiver 20 receives the above-described high frequency signal. For example, the high frequency receiving unit 20 receives a high frequency signal from the key terminal 110 in communication for unlocking a lock provided in the vehicle.

  The high frequency receiving unit 20 converts the received high frequency signal into an intermediate signal having a frequency lower than that of the high frequency signal. For example, the high frequency receiving unit 20 multiplies the received high frequency signal by a predetermined local signal to generate an intermediate signal having a frequency difference between the frequency of the high frequency signal and the frequency of the local signal. The frequency of the intermediate signal is a frequency at which signal processing can be performed in the signal processing unit 60 in the subsequent stage.

  The signal processing unit 60 processes the intermediate signal. For example, the signal processing unit 60 converts the intermediate signal into a digital signal. The signal processing unit 60 may demodulate the intermediate signal. The signal processing unit 60 may perform processing for comparing the identification information of the key terminal 110 included in the intermediate signal with preset information. In another example, in the subsequent circuit to which the output signal of the signal processing unit 60 is input, a process of collating the identification information of the key terminal 110 with predetermined information may be performed.

  The input switching unit 40 switches whether to input a signal from the high frequency receiving unit 20 or a low frequency signal from the power source operation unit 120 to the signal processing unit 60. For example, when the input switching unit 40 receives a low frequency signal from the power source operation unit 120, the input switching unit 40 inputs the low frequency signal to the signal processing unit 60. The control of the lock using the high frequency signal and the start of the power source using the low frequency signal do not need to be performed at the same time, and can be processed by the common signal processing unit 60. The low frequency signal has a frequency and a frequency bandwidth that can be processed by the signal processing unit 60. The frequency of the low frequency signal may be the same as the frequency of the intermediate signal. Moreover, the high frequency receiver 20 may have a configuration for switching the frequency of the intermediate signal to be converted. For example, the high frequency receiving unit 20 has a configuration for switching the frequency of a local signal to be multiplied by the high frequency signal.

  The input switching unit 40 of this example includes a switch 41 and a switch 42. The switch 41 switches whether to input a low frequency signal to the signal processing unit 60. The switch 42 switches whether to input a high frequency signal to the signal processing unit 60. The switch 41 and the switch 42 are controlled so as not to be turned on simultaneously.

  With such a configuration, the high-frequency signal and the low-frequency signal can be processed by the common signal processing unit 60. For this reason, the circuit scale can be reduced.

  In addition, it is preferable that the input switching unit 40, the high frequency receiving unit 20, and the signal processing unit 60 are formed on the same chip 10. The chip 10 may have a single semiconductor substrate. The chip 10 of this example is an integrated circuit in which an input switching unit 40, a high frequency receiving unit 20, and a signal processing unit 60 are integrated.

  The chip 10 has a terminal 12, a terminal 14, and a terminal 16. A power source operation unit 120 and a switch 41 are connected to the terminal 12. An antenna that receives a high-frequency signal from the key terminal 110 and the high-frequency receiving unit 20 are connected to the terminal 14. The signal processing unit 60 and a predetermined external device are connected to the terminal 16.

  By providing the input switching unit 40, the high-frequency receiving unit 20, and the signal processing unit 60 on the same chip 10, the number of chips is reduced as compared with the case of using a high-frequency signal chip and a low-frequency signal chip. be able to. Further, the signal processing device 100 can be downsized, and space saving in the target device such as a vehicle can be realized. In particular, in the vicinity of the start button, the degree of integration of components is often high, and the small signal processing apparatus 100 is useful.

  FIG. 2 is a diagram illustrating a configuration example of the input switching unit 40, the high frequency receiving unit 20, and the signal processing unit 60. The high frequency receiver 20 of this example includes a low noise amplifier 21, a high frequency amplifier 22, a differential amplifier 23-1, a differential amplifier 23-2, a mixer 24-1, a mixer 24-2, a transimpedance amplifier 26-1, a transformer An impedance amplifier 26-2 and a distribution unit 25 are included.

  The low noise amplifier 21 receives a high frequency signal having a relatively low signal level and amplifies it to a predetermined signal level. The low noise amplifier 21 generates less noise than the subsequent amplifier. The high frequency amplifier 22 further amplifies and outputs the high frequency signal amplified by the low noise amplifier 21. The output of the high frequency amplifier 22 is input to each of the two differential amplifiers 23.

  Each differential amplifier 23 converts the input high-frequency signal into a differential signal and outputs the differential signal. Each mixer 24 multiplies the high-frequency signal input from the differential amplifier 23 by a local signal having a predetermined frequency. As a result, an intermediate signal having a frequency difference between the high-frequency signal and the local signal is generated. Each mixer 24 receives local signals having a phase difference of 90 degrees. As a result, each mixer 24 outputs an intermediate signal of I phase (in-phase) and Q phase (orthogonal phase) that are 90 degrees out of phase.

  The distribution unit 25 makes the phase of the local signal having a predetermined frequency differ by 90 degrees and inputs it to each mixer. The distribution unit 25 inputs a differential local signal to each mixer 24. The distribution unit 25 may receive a local signal from the oscillator 30 provided in the chip 10 or may receive a local signal from the outside of the chip 10. The oscillator 30 is, for example, a voltage controlled oscillator. Each transimpedance amplifier 26 converts an intermediate signal of the current signal input from the mixer 24 into an intermediate signal of a voltage signal and inputs the converted signal to the input switching unit 40.

  The input switching unit 40 receives a low frequency signal from the terminal 12 and receives an intermediate signal from the high frequency receiving unit 20. The input switching unit 40 of this example includes a switch 41, a switch 42, a switch 43, a switch 44, a switch 45, and a switch 47. The signal processing unit 60 of this example has differential input ends for each of the I-phase side and the Q-phase side.

  The switch 41 is provided between the terminal 12 and one terminal of the differential input end on the I-phase side of the signal processing unit 60. The switch 42-1 is provided between one of the differential input ends on the I-phase side of the signal processing unit 60 and the high-frequency receiving unit 20.

  The switch 42-2 is provided between the other terminal of the differential input end on the I-phase side of the signal processing unit 60 and the high-frequency receiving unit 20. The switch 43 is provided between the other terminal of the differential input end on the I-phase side of the signal processing unit 60 and a predetermined common potential Vcom. The common potential Vcom is, for example, a common potential for differential signals.

  The switch 41 and the switch 43 operate in synchronization. That is, when the switch 41 is turned on, the switch 43 is also turned on, and when the switch 41 is turned off, the switch 43 is also turned off. The switch 42-1 and the switch 42-2 operate so as not to be turned on simultaneously with the switch 41 and the switch 43.

  When a low frequency signal is input to the signal processing unit 60 by the operation of such a switch, the low frequency signal is input to one terminal of the differential input end on the I-phase side of the signal processing unit 60. A predetermined common potential Vcom is applied to the other terminal of the differential input terminal on the I-phase side of the signal processing unit 60.

  The switch 44 is provided between the common potential and one terminal of the differential input end on the Q phase side of the signal processing unit 60. The switch 45-1 is provided between one terminal of the differential input end on the Q phase side of the signal processing unit 60 and the high frequency receiving unit 20.

  The switch 45-2 is provided between the other terminal of the differential input end on the Q phase side of the signal processing unit 60 and the high frequency receiving unit 20. The switch 47 is provided between the other terminal of the differential input end on the Q-phase side of the signal processing unit 60 and a predetermined common potential Vcom.

  The switch 44 and the switch 47 operate in synchronization. That is, when the switch 44 is turned on, the switch 47 is also turned on, and when the switch 44 is turned off, the switch 47 is also turned off. The switch 45-1 and the switch 45-2 operate so that the switch 44 and the switch 47 are not turned on at the same time. When a low frequency signal is input to the signal processing unit 60, the switch 44 and the switch 47 are turned on, and the switch 45-1 and the switch 45-2 are turned off. When the intermediate signal is input to the signal processing unit 60, the switch 44 and the switch 47 are turned off, and the switch 45-1 and the switch 45-2 are turned on. That is, when a low frequency signal is input to the signal processing unit 60, the same common potential is input to each of the differential input terminals on the Q phase side of the signal processing unit 60.

  The signal processing unit 60 of this example includes an anti-aliasing filter 61, a limiting amplifier 62, and an AD converter 63 on each of the I-phase side and the Q-phase side. Either the intermediate signal or the low-frequency signal selected by the input switching unit 40 is input to the antialiasing filter 61.

  The anti-aliasing filter 61 removes aliasing components in the input signal. For example, the antialiasing filter 61 removes aliasing components generated in the mixer 24. The switch 41 in the example of FIG. 2 is connected to the input terminal of the antialiasing filter 61-1, but the switch 41 in the other example is connected between the terminal 12 and the input terminal of the limiting amplifier 62-1. Also good. That is, the low frequency signal may be input to the limiting amplifier 62-1 without passing through the anti-aliasing filter 61-1.

  The limiting amplifier 62 limits the amplitude of the signal output from the antialiasing filter 61. The limiting amplifier 62 limits the amplitude of the signal input to the AD converter 63 at the subsequent stage to an amplitude suitable for the AD converter 63 to process.

  The AD converter 63 converts the signal input from the limiting amplifier 62 into a digital signal. The AD converter 63 is, for example, a ΔΣ type AD converter.

  The signal processing unit 60 may further include a digital processing unit that processes the digital signal output from the AD converter 63. For example, the signal processing unit 60 may include a digital filter, a digital demodulation unit, and the like. For example, the digital filter and the digital demodulator are digital circuits configured with a delay circuit, a logic circuit, and the like to perform predetermined digital processing.

  The chip 10 of this example has a setting unit 64. The setting unit 64 controls the input switching unit 40. For example, the setting unit 64 includes a register that stores a control value of each switch in the input switching unit 40. The control value is set according to which of the low frequency signal and the intermediate signal is input to the signal processing unit 60. When a low frequency signal is input to the chip 10, the low frequency signal may be preferentially input to the signal processing unit 60.

  The setting unit 64 may further control the signal processing device 100 according to which of the low frequency signal and the intermediate signal is input to the signal processing unit 60. For example, when processing the low-frequency signal, the setting unit 64 may stop the operations of the anti-aliasing filter 61-2, the limiting amplifier 62-2, and the AD converter 63-2 on the Q phase side, and supply power. You may stop. The setting unit 64 may switch the signal processing target frequency in the signal processing unit 60 and the frequency bandwidth. The setting unit 64 may be capable of switching the center frequency and frequency bandwidth of the signal to be processed in the signal processing unit 60 to a plurality of predetermined values. As an example, the signal processing unit 60 switches the signal processing frequency and the reception bandwidth in response to a switching instruction from the setting unit 64. The setting unit 64 may change the cutoff frequency of the anti-aliasing filter 61, and may change the frequency of the operation clock input to the AD converter 63 and the like.

  When at least one of the frequency and the frequency bandwidth is different between the intermediate signal and the low frequency signal, the setting unit 64 determines whether the signal processing unit 60 receives the intermediate signal or the low frequency signal based on which of the intermediate signal and the low frequency signal is input. At least one of the target frequency and the frequency bandwidth in the processing unit 60 may be set. In addition, when the frequency and frequency bandwidth of the intermediate signal output from the high frequency receiver 20 are variable, the setting unit 64 is a signal processor according to the frequency and frequency band of the intermediate signal output from the high frequency receiver 20. The target frequency and frequency bandwidth at 60 may be set. The setting unit 64 may change the gain for the low frequency signal input from the terminal 12. By adjusting the gain, the communication distance in the short-range wireless communication between the key terminal 110 and the signal processing device 100 can be adjusted.

  With such a configuration, even if the frequency of the intermediate signal is different from the frequency of the low frequency signal, the signal processing unit 60 can process the intermediate signal and the low frequency signal. For this reason, it is not necessary to provide a processing circuit for each of the intermediate signal and the low frequency signal, and the circuit scale can be reduced.

  FIG. 3 is a diagram illustrating an example of the overall configuration of the signal processing apparatus 100. The signal processing apparatus 100 of this example includes a chip 10, an MPU 70, a signal output unit 72, a network driver 74, a PMIC 76, and a filter 78. The chip 10 is the same as the chip 10 described in FIG. 1 and FIG.

  The filter 78 receives a high frequency signal via the antenna 80. The filter 78 inputs a signal component of a predetermined band in the received high frequency signal to the terminal 14 of the chip 10.

  The PMIC 76 supplies power received from a power source such as a vehicle battery to each circuit such as the chip 10. The PMIC 76 may adjust the voltage and current of power supplied to the chip 10 and the like. Further, the PMIC 76 may limit the power supplied to the chip 10 or the like when an overcurrent, overvoltage, or overheating occurs in the chip 10 or the like.

  The MPU 70 is an example of an external processing unit that is provided outside the chip 10 and processes a network signal that communicates with a network in a target device such as a vehicle. The MPU 70 communicates with a network mounted on the vehicle via the network driver 74.

  The network driver 74 controls each device such as a door lock, a lamp, an air conditioner, and a display via a network mounted on the vehicle. For example, the network driver 74 unlocks the door when receiving a control signal for unlocking the door from the MPU 70. At this time, the network driver 74 may blink a hazard lamp or the like of the vehicle, or may generate a buzzer sound notifying that the vehicle has been unlocked. The network driver 74 may monitor the state of each device mounted on the vehicle via the network.

  The MPU 70 is connected to the chip 10. The MPU 70 processes a signal output from the chip 10. For example, the MPU 70 generates a control signal for controlling a vehicle door or the like according to a signal output from the chip 10 according to a high-frequency signal. The MPU 70 supplies the generated control signal to the network driver 74.

  The chip 10 receives a low-frequency signal via a transmission / reception unit provided in the vicinity of a key cylinder or a start button. The MPU 70 processes a signal output from the chip 10 according to the low frequency signal, and generates a signal according to the processing result. For example, the MPU 70 authenticates the key terminal 110 according to a signal output from the chip 10. When the key terminal 110 is authenticated and the MPU 70 detects that a predetermined operation has been performed on the key cylinder or the like, the MPU 70 generates a start signal for starting the power source. The MPU 70 supplies the generated start signal to the signal output unit 72 that is a separate circuit from the chip 10. The signal output unit 72 operates the starting motor of the power source based on the starting signal generated by the MPU 70. For example, the signal output unit 72 is a driver that applies a voltage and a current to a subsequent circuit in accordance with a digital start signal input from the MPU 70.

  The MPU 70 may generate a data pattern to be transmitted to the key terminal 110 in accordance with a signal output from the chip 10. In this case, the MPU 70 inputs the data pattern to the signal output unit 72. The data pattern may be a pattern requesting transmission of a low frequency signal. The signal output unit 72 generates a transmission signal corresponding to the data pattern and transmits it to the transmission / reception unit. With such a configuration, it is possible to communicate with the key terminal 110 using the MPU 70 and the signal output unit 72 provided outside the chip 10. In addition, since the signal output unit 72 that controls the starting motor is used in communication with the key terminal 110, the circuit scale can be reduced.

  FIG. 4 is a diagram illustrating a configuration example of a control system 200 that controls the vehicle. The control system 200 includes a signal processing device 100, a key terminal 110, an immobilizer unit 122, an air pressure measurement unit 130, and a starter motor 140. The immobilizer unit 122 includes, for example, the above-described key cylinder or start button, and a short-range wireless communication unit.

  The air pressure measurement unit 130 measures the air pressure of each tire of the vehicle. The air pressure measurement unit 130 notifies the signal processing apparatus 100 of the measurement result by wireless communication. The signal transmitted by the air pressure measurement unit 130 may be a signal having a frequency similar to that of the high frequency signal. The signal transmitted by the air pressure measurement unit 130 may be received by the antenna 80. When the air pressure of one of the tires is out of the predetermined range, the signal processing device 100 notifies the warning by voice through the network in the vehicle or displays the warning.

  The signal processing apparatus 100 of this example is for (1) a high-frequency signal for controlling the lock of the door, (2) a high-frequency signal for notifying the location of the vehicle, and (3) notifying a measurement result of the tire air pressure. The high frequency signal of (4) and the low frequency signal for immobilizer can be processed by one chip 10. For this reason, the number of parts can be reduced and the circuit scale can be reduced.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

DESCRIPTION OF SYMBOLS 10 ... Chip | tip, 12, 14, 16 ... Terminal, 20 ... High frequency receiving part, 21 ... Low noise amplifier, 22 ... High frequency amplifier, 23 ... Differential amplifier, 24 ... Mixer, 25 ... distributing unit, 26 ... transimpedance amplifier, 30 ... oscillator, 40 ... input switching unit, 41, 42, 43, 44, 45, 47 ... switch, 60 ..Signal processing unit 61... Antialias filter 62. Limiting amplifier 63... AD converter 64... Setting unit 70. 74 ... Network driver, 76 ... PMIC, 78 ... Filter, 80 ... Antenna, 100 ... Signal processing device, 110 ... Key terminal, 120 ... Power source operation unit, 122 ... Immobili Parts, 130 ... pressure measuring unit, 140 ... starter motor, 200 ... control system

Claims (9)

A signal processing device for processing a signal for controlling starting of a power source provided in a target device,
Receiving a high-frequency signal and converting it to an intermediate signal having a frequency lower than the high-frequency signal;
A signal processing unit for processing the intermediate signal;
In communication for authentication when starting the power source of the target device, a low frequency signal having a frequency lower than that of the high frequency signal is received, and the intermediate signal is input to the signal processing unit, or An input switching unit that switches whether to input the low-frequency signal. The signal processing device according to claim 1, further comprising a setting unit configured to set at least one of a target frequency or a frequency bandwidth of signal processing in the signal processing unit. The signal processing apparatus according to claim 1, wherein the input switching unit, the high-frequency receiving unit, and the signal processing unit are formed on the same chip. The signal processing device according to claim 3, further comprising a signal output unit that is provided outside the chip and outputs a start signal for starting the power source. An external processing unit that is provided outside the chip and processes a network signal that communicates with a network in the target device;
The signal processing apparatus according to claim 4, wherein the external processing unit generates the start signal and inputs the start signal to the signal output unit. The external processing unit generates a data pattern to be transmitted to the outside according to a signal output from the chip, and inputs the data pattern to the signal output unit.
The signal processing device according to claim 5, wherein the signal output unit generates a transmission signal corresponding to the data pattern. The signal processing device according to any one of claims 1 to 6, wherein the high-frequency signal is a signal for unlocking a lock provided in the target device. The signal processing device according to claim 1, wherein the high-frequency signal is a signal that operates at least one of a lamp and a buzzer provided in the target device. The signal processing device according to any one of claims 1 to 8, wherein the high-frequency signal is a signal indicating a measurement result of an air pressure of a tire provided in the target device.

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