KR100466020B1 - Distance Detecting Circuit of Door Locking Device - Google Patents

Abstract

The present invention relates to a distance sensing circuit of a vehicle door locking device that locks and unlocks a door of a vehicle through radio communication.

A distance sensing circuit of a door lock device that locks and unlocks a door through radio communication, the distance sensing circuit comprising: an antenna for receiving radio waves generated from a wave generator possessed by a user, and received by the antenna; A demodulation circuit for demodulating the received radio wave and a voltage and a reference voltage of the signal demodulated by the demodulation circuit, and when the voltage of the demodulation signal is higher than the reference voltage, outputs a first output and the voltage of the demodulation signal is higher than the reference voltage. If it is low, a second output includes a comparator and a reference voltage generator circuit for generating the reference voltage, wherein the reference voltage generator circuit is configured to vary the reference voltage to be generated according to temperature.

In this way, if the reference voltage is varied according to the temperature, the device detects the distance of the radio wave transmission apparatus based on the strength of the signal transmitted by the portable radio wave transmission apparatus. There is a lot of error in doing so. In particular, when the receiver is installed in the vehicle, the temperature inside the vehicle may rise to 92 ° C., especially during summer, so that the error becomes more severe. However, according to the present invention, even in a case where the temperature changes suddenly in summer or winter, the sensing distance is provided to maintain a constant and accurate effect.

Description

Distance Detecting Circuit of Door Locking Device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distance sensing circuit of a door lock device that locks and unlocks a door through radio communication, and more particularly, to a distance sensing circuit of a door lock device that maintains a constant sensing distance regardless of temperature change.

A door locking device for locking a door and releasing a locked state through radio communication is disclosed in International Patent Application Publication No. WO 02/38895 filed by the present applicant. The door locking device disclosed in the above publication discloses a lock state of the door when the main device on the door side and the wireless communication card carried by the user communicate with each other through radio waves, for example, microwaves. Release the door and lock the door when the user moves out of the predetermined distance. The door may be a door of a vehicle, may be a door of a house, and is not limited to a target to which the door is mounted.

However, in the system for locking and releasing the door of the vehicle through the radio communication between the main device on the door side and the radio communication card, the sensing distance for detecting the user carrying the radio communication card must be kept constant.

Particularly, in the case of a door lock device of a vehicle, if the vehicle is parked outdoors in a hot summer, the temperature inside the vehicle may rise to about 92 ° C. An error occurs in the data about the distance measured by the receiver, such that the door lock device may not be released even if the user carrying the wireless communication card is within a predetermined distance. In addition, there is a problem that the sensing distance that the locked state of the door is released or locked also varies according to the temperature in the vehicle.

An object of the present invention is to provide a distance detection circuit for a vehicle door lock device that can maintain a constant sensing distance at all times without being affected by the temperature inside the vehicle in the door lock device through wireless communication to solve this problem. do.

1 is a system block diagram of a door locking device according to the present invention.

2 is a block diagram of a main device of the system shown in FIG.

3 is a block diagram of the wireless communication card shown in FIG.

4 is a block diagram of a remote control transmitter shown in FIG.

5 is a block diagram of a distance sensing circuit according to a first embodiment of the present invention.

6 is a block diagram of a distance sensing circuit according to a second embodiment of the present invention.

7 is a block diagram of a distance sensing circuit according to a third embodiment of the present invention.

The distance sensing circuit of the door locking device according to the first aspect of the present invention for achieving the object of the present invention, the antenna for receiving the radio wave generated from the radio wave generator possessed by the user, and the radio wave received by the antenna Compares a demodulation circuit for demodulating a signal with a voltage of a signal demodulated by the demodulation circuit and a reference voltage, and outputs a first output when the voltage of the demodulation signal is higher than a reference voltage, and when the voltage of the demodulation signal is lower than a reference voltage. And a comparator for outputting a second output and a reference voltage generator circuit for generating the reference voltage, wherein the reference voltage generator circuit allows the reference voltage to be generated to vary with temperature.

According to such a distance sensing circuit, since the reference voltage varies with temperature, even if the characteristics of the receiver change with temperature, an accurate and constant sensing distance is always maintained.

The distance sensing circuit of the door locking device according to the second aspect of the present invention is the distance sensing circuit of the first aspect, wherein the reference voltage generating circuit includes a temperature sensor.

In the distance sensing circuit according to the first or second aspect of the third aspect of the present invention, the temperature sensor is any one of a thermistor, resistance temperature detector, and semiconductor temperature sensor.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Although the door locking device described as an embodiment herein is applied to a vehicle, it should be understood that the present invention is not limited to the door locking device of the vehicle.

[First Embodiment]

1 shows a system block diagram of a door lock of a vehicle using a wireless communication card, comprising a reference voltage generator circuit according to the invention.

The system includes a main device 100, a remote control transmitter 300, a wireless communication card 200, a door switch unit 500, and a vehicle controller 400.

The main device 100 is mounted inside the vehicle and receives the first and third microwaves VHF1 and VHF3 transmitted from the wireless communication card 200 and outputs a door unlock signal when the IDs match. The vehicle control unit 400 is connected to the output side of the main device 100, the start and stop of the vehicle, the locking / unlocking of the door, the generation of alarm sounds, etc. by the control signal output from the main device 100 Perform the action.

2 is a detailed block diagram of the main device 100 and the vehicle control unit 400.

The main device 100 includes a first microprocessor 110, a first microwave transceiver 140, a first microwave transmit / receive antenna 150, an ypyrom 160, and a constant voltage circuit 170.

The first microwave transceiver 140 generates a second microwave VHF2 to be transmitted to the wireless communication card 200. The first microwave transmit / receive antenna 150 transmits a second microwave VHF2 output from the microwave receiver 140 to a space.

The microwave transmit / receive antenna 150 includes first and third microwaves VHF1 and VHF3 including a catch signal and a door release signal transmitted from the wireless communication card 200, and a remote device installed inside the vehicle. When the driver operates the start button, the mode button, or the forced alarm button, the adjustment transmitter 300 receives the fourth microwave VHF4 transmitted from the remote control transmitter 300, and checks the check items set when setting other functions. It is sent to the remote control transmitter 300 as the fifth ultra-high frequency VHF5.

The first microprocessor 110 is connected to an input terminal and an output terminal of the microwave transceiver 120. The first microprocessor 110 compares and analyzes the signals transmitted from the wireless communication card 200 and the remote control transmitter 300 to read the first microwave transceiver. The ID confirmation signal is transmitted through the 140, and a predetermined control signal is output to the vehicle controller 400. One side of the first microprocessor 110 is connected to the Y pyrom 160, which stores the ID of the wireless communication card and data related to the control of the system, and the opening and closing signal of the door to the first microprocessor 110 The door switch part 500 to transmit is connected.

The vehicle controller 400 is connected to an output terminal of the first microprocessor 110. The vehicle control unit 400 applies a current to the ignition coil of the vehicle when operating the start button of the remote control transmitter 300 to start the start control circuit 420 and sends a vehicle width light and an alarm sound when the forced alarm button is operated. The vehicle door lighting circuit 430, the forced alarm control circuit 440, and the door control circuit 410 for locking and unlocking the door in accordance with the access of the wireless communication card 200.

The remote control transmitter 300 is installed inside the vehicle, and the driver transmits an operation signal of the fourth microwave VHF4 to the main device 100 when the driver operates the start button, the mode button, and the forced alarm button. ) Transmits the confirmation items set when setting other functions to the fifth microwave (VHF5) to confirm the function settings.

4 is a detailed block diagram of a remote control transmitter 300 installed in a vehicle according to the present invention. As shown in FIG. 4, the remote control transmitter 300 includes a start button 340, a mode button 350, a forced alarm button 360, an automatic start switching switch 370, and a third microprocessor 310. , Microwave transceiver 320 and battery 330.

The third microprocessor 310 outputs a control signal proportional thereto when the buttons 340 to 370 are operated. The second microwave transceiver 320 transmits a fourth microwave VHF4 that is an operation signal to the main device 100 according to the control signal of the third microprocessor 310. In addition, according to a preferred embodiment of the present invention, the remote control transmitter 300 is an operating state display lamp 380 for displaying an operating state and an automatic or manual operating state under the control of the third microprocessor 310. And landmark lamps 390, battery status indicator lamps for vehicles and wireless communication cards.

The main device 100 receives the first microwave VHF1 including the catch signal and the ID transmitted by the wireless communication card 200, verifies the ID included in the first microwave VHF1. When there is a match among the stored IDs, the second microwave VHF2 including the confirmation signal is transmitted, and the third microwave VHF3 including the door lock state release command is received.

The wireless communication card 200 transmits the first microwave VHF1 including the catch signal and the ID. When the main device 100 transmits the second microwave VHF2 including the ID confirmation signal, the wireless communication card 200 receives the second microwave VHF2. The third microwave VHF3 including the door lock release command is transmitted.

The door switch unit 500 is connected to the input terminal of the main device 100 and transmits a lock signal of the door to the main device 100. The wireless communication card 200 and the main device 100 operate through a process of mutually confirming that they are the owners of the vehicle through bidirectional data communication, so that the vehicle cannot be operated without the wireless communication card corresponding to the vehicle.

3 shows a detailed block diagram of a wireless communication card 200 in accordance with the present invention. As shown in FIG. 3, the wireless communication card 200 includes a second microwave transceiver 250, a second microwave transceiver 260, a second microprocessor 210, a switching circuit 220, and a function button ( 230 and battery 240. The function button 230 may be one or plural. The wireless communication card 200 is not limited to the form of the card, but may take the form of a remote controller or various various forms.

The second microwave transceiver 250 transmits the first and third microwaves VHF1 and VHF3 to the main device 100 through the second microwave transmit / receive antenna 260, and the main device 100 transmits the first and third microwaves VHF1 and VHF3. 2 Receives very high frequency (VHF2). The switching circuit 220 supplies the power of the battery 240 to the second microprocessor 210 by the synchronization signal and the function button 230.

On the other hand, the remote control transmitter and the main device 100 may communicate with each other by wire. The remote control transmitter may receive power supplied from the vehicle battery via the main device 100 without installing a separate battery.

5 is a block diagram of a distance sensing circuit according to a first embodiment of the present invention. The distance sensing circuit includes a microwave receiving antenna 150 for receiving microwaves transmitted by the wireless communication card 200, a first band pass filter 2, a first amplifier 3, a mixer 4, A second band pass filter 5, a second amplifier 6, a detector 7, a first comparator 8, a first buffer amplifier 9, and a voltage controlled oscillator 10. ), Loop filter 11, reference oscillator 18, phase detector 12, low pass filter 13, second comparator 14, second buffer amplifier 15, and a reference voltage generator 16.

The signal received by the microwave receiving antenna 150 passes only the band set to receive while passing through the first band pass filter 2, and the rest of the signal is attenuated. For example, a surface acoustic wave filter may be used as the first band pass filter 2. The signal passing through the first band pass filter 2 is first amplified by the first amplifier 3 and enters the mixer 4 and is mixed with the local signal.

The frequency of the local signal is obtained by dividing the frequency oscillated by the voltage adjusting oscillator 10 by 68, comparing this frequency with the frequency oscillated by the reference oscillator 18 and its phase in the phase detector 12, and then outputting the difference. It is made by varying the frequency of the voltage adjusting oscillator 10 by making it the average voltage from which phase noise is removed in the loop filter. The value dividing the frequency oscillated by the voltage controlled oscillator 10 can be changed depending on the designer or the type of semiconductor used. The frequency Fo of the local signal is determined by the frequency Fs and the intermediate frequency Fi of the received signal. That is Fo = Fs-Fi.

The frequency of the signal passed through the first amplifier 3 and the local signal mixed in the mixer 4 is Fs, Fo, Fs + Fo, Fs-Fo, etc., and the signal is the second band pass filter 5 ), Only the signal of Fs-Fo frequency passes and the signal of the rest of the frequency does not pass and is attenuated. The signal passing through the second band pass filter 5 is amplified while passing through the second amplifier 6 and passes through the detector 7, leaving only the audio signal, which passes through the first comparator 8 and the digital signal. Is converted to. Since the converted signal has high impedance, data may be damaged by the line. Therefore, this signal is output as data after changing the impedance via the first buffer amplifier 9.

Determining whether or not the wireless communication card 200 that has transmitted the microwave is within a predetermined sensing distance detects the signal from the detector 7, removes the noise by the low pass filter 13, and then the second comparator 14. ), The voltage of the signal is compared with the voltage generated by the reference voltage generating circuit 16, and if the voltage of the signal is higher than the reference voltage, it is determined by sending a "High" output. This output allows the output of the distance to pass through the second buffer amplifier 15 so as not to be affected by the outside. The signal from the detector 7 is detected by a voltage or a received signal strength indicator (RSSI) voltage that varies with the strength of the signal.

The RSSI voltage is compared with the reference voltage generated by the reference voltage generating circuit 16 to check whether the user having the wireless communication card 200 is within a predetermined sensing distance. The reference voltage generating circuit includes a temperature sensor, It is generated by changing the reference voltage according to the temperature. The temperature sensor may be a thermistor, resistance temperature detector, semiconductor temperature sensor, or the like. Referring to FIG. 8, a circuit for generating a reference voltage will be described. As shown in FIG. 8, the thermistor TH refers to an element whose resistance value changes with temperature, and the resistance value of the thermistor TH changes with temperature. Using the general characteristics, the fixed resistors R1 and R2 and thermistor TH are configured in series in the voltage distribution circuit. Here, the reference voltage is the relative potential difference generated between the fixed resistors R1 and R2 and the thermistor TH, that is, the voltage across the node N1. The reference voltage and the RSSI voltage are compared in a comparator CC. Therefore, since the reference voltage is generated by changing according to the temperature, even if the characteristic change of the microwave receiving unit occurs depending on the temperature, the sensing distance can be kept constant.

Second Embodiment

6 is a block diagram of a distance sensing circuit according to a second embodiment of the present invention.

The distance sensing circuit according to the second embodiment includes an antenna 150 for receiving microwaves transmitted by the wireless communication card 200, a first band pass filter 2, a first amplifier 3, and a mixer 4. ), A local oscillator 20, a second band pass filter 5, a second amplifier 6, a detector 7, a first comparator 8, a first buffer amplifier 9, The signal voltage detector 21, the second comparator 14, the second buffer amplifier 15, and the reference voltage generator 16 are included. The same reference numerals are given to the same components as the circuit of the first embodiment.

The signal received by the antenna 150 passes only the band set to be received by the first band pass filter 2 and attenuates the rest. A surface acoustic wave filter may be used for the first band pass filter 2 as in the first embodiment. The signal passing through the first band pass filter 2 is amplified in the first amplifier 3 and mixed with the local signal in the mixer. The frequency of the local signal is generated using an X-TAL oscillator circuit or an LC oscillator circuit. The frequency Fo of the local signal is determined by the frequency Fs and the intermediate frequency Fi of the received signal. That is, local frequency Fo = reception frequency Fs-intermediate frequency Fi.

The signal received in this way and mixed with the local signal and the local signal, and the signal from the mixer 4 has a frequency of Fs, Fo, Fs + Fo, Fs-Fo, etc. The second band pass filter 5 Passing) will leave only the signal with frequency Fs-Fo and will attenuate the signal with the remaining frequency. The signal from the second band pass filter 5 is amplified by the second amplifier 6 and passed through the detector 7, leaving only the audio signal, which is passed through the first comparator 8 to a digital signal. This signal is again output through the first buffer amplifier 9 in order to prevent the characteristic of the first comparator 8 from changing externally.

On the other hand, the audio signal from the detector 7 is converted into a DC signal that changes according to amplitude, and is then used by the signal voltage detector 21 for automatic gain control (AGC) of the primary and secondary amplifier stages. . This signal is compared with the reference voltage in the second comparator 14, and if it is higher than the reference voltage, an output of "High" is output and this output is passed through the second buffer amplifier 15 so that it is not affected by the outside. Is output.

Third Embodiment

7 is a block diagram of a distance sensing circuit according to a third embodiment of the present invention.

The distance sensing circuit of the third embodiment includes a microwave receiving antenna 150 for receiving microwaves transmitted by the wireless communication card 200, a first band pass filter 2, a first amplifier 3, and a mixer 4 ), A second band pass filter (5), a voltage controlled oscillator (10), a loop filter (11), a reference oscillator (18), a phase detector (12), , A comparator 14, a buffer amplifier 15, and a reference voltage generator 16.

The signal received through the antenna 150 is mixed with the local signal in the mixer 4 and passed through the second band pass filter 5 as in the first embodiment. The third embodiment differs from the first embodiment in that the signal from the second band pass filter 5 enters an intermediate frequency demodulator 40 (IF Demodulator). The signal entering the intermediate frequency demodulator 40 is amplified by an amplifier stage inside the demodulator 40 and mixed with the signal of the frequency generated by the local oscillator 21, which is then mixed with the third band pass filter. The signal is converted into a signal having a predetermined band frequency by 30, detected by a discriminator or a tuning circuit, and an audio signal is output. The signal is converted into a digital signal by an amplifier inside the demodulator 40 and output.

On the other hand, there is an RSSI signal in the output of the intermediate frequency demodulator 40, which is compared with the reference voltage in the comparator 14, and outputs a "High" output when the voltage is higher than the reference voltage, so as not to be affected by the outside. In order to output through the buffer amplifier 15.

Although the above-described embodiment relates to a distance sensing circuit applied to a door locking device of a vehicle, the distance sensing circuit according to the present invention is not limited to a door locking device of a vehicle, and locks a door and releases a lock state through radio communication. It can be applied to any door lock. In addition, the main device mounted on the door side and the wireless communication card do not perform bidirectional communication, and are applicable to a door locking device that transmits microwaves in one direction only from the wireless communication card to the main device.

The scope of the present invention is not limited to the configuration of the above-described embodiment, but is determined by the appended claims, and as long as the technical idea of the present invention is included, the improvement or modification of the invention described in the claims is also present. Obviously, it belongs to the scope of the invention.

According to the present invention, a vehicle door lock device in which a door of a vehicle is automatically unlocked only by a user approaching the vehicle without having a mechanical key by the communication between the wireless communication card and the main device inside the vehicle. Even when the temperature inside the vehicle changes rapidly, such as in summer or winter, the distance detection for recognizing the wireless communication card is kept constant.

Claims (3)

A distance sensing circuit of a door lock device that locks and unlocks a door through radio communication, wherein the distance sensing circuit includes: An antenna for receiving radio waves generated from a wave generator owned by the user; A demodulation circuit for demodulating a radio wave received by the antenna; A comparator for comparing the voltage of the signal demodulated by the demodulation circuit with a reference voltage, and outputting a first output if the voltage of the demodulation signal is higher than the reference voltage and outputting a second output if the voltage of the demodulation signal is lower than the reference voltage; , A reference voltage generator circuit for generating the reference voltage; And the reference voltage generator circuit includes a temperature sensor, wherein the reference voltage generator is configured to vary the generated reference voltage according to temperature. (delete) The method of claim 1, The temperature sensor is any one of a thermistor, a resistance temperature detector, and a semiconductor temperature sensor.