PEPS key low-frequency field intensity-based consistency verification system and method

Abstract

The invention discloses a consistency detection system and method based on PEPS key low-frequency field intensity, and the system comprises a Helmholtz coil and a to-be-detected PEPS key, and the PEPS key and the Helmholtz coil are disposed in a shielding box. A Helmholtz coil is driven to emit magnetic fields in three directions, corresponding magnetic field signals are received by X, Y and Z low-frequency antennas of a PEPS key, corresponding magnetic field intensity is acquired and sensed, and then magnetic field intensity signals emitted by a PEPS module are acquired; and the upper computer analyzes the received magnetic field intensity signals in three directions sent by the PEPS key to obtain the field intensity data of the three channels. The method has the advantages that the field intensity consistency test on the PEPS key is simply and reliably realized, the hardware cost is low, and the test operation is convenient.

Description

Technical Field

[0001] The invention relates to the field of testing of automobile PEPS keys, and in particular to a consistency verification system and method based on low-frequency field strength of a PEPS key. Background Art

[0002] At present, PEPS smart keys are becoming more and more popular in cars. The field strength value of the low-frequency antenna is used to locate the key, and the field strength consistency of the key is very high. In this context, it is particularly important to improve the consistency of the low-frequency field strength. In order to accurately locate the position information of the key inside and outside the car, the consistency of the field strength of the key at the same point is very high. Due to the impedance difference of the hardware circuit of the circuit matching of the low-frequency antenna, the deviation of capacitance and resistance, etc., the consistency of the low-frequency field strength is not good. If there is a difference in the consistency of the low-frequency field strength, it will cause inaccurate positioning, and then there will be erroneous actions on the opening and closing of the PEPS key to lock the door, affecting the accuracy of the function of the PEPS key. A common test in the prior art is the PEPS function test, such as a test device and method for a PEPS system with patent application number 201410005705.2, which belongs to the field of automotive technology. The test device of the PEPS system includes: a door handle antenna monitoring module, which is used to check whether the door handle antenna is working properly; a door lock status generation module, which is used to generate a door lock status signal after the door handle antenna monitoring module checks that the door handle antenna is working properly, and send the door lock status signal to the body controller; the body controller is used to convert the received door lock status signal into a CAN signal and send it to the CAN bus; the CAN signal monitoring module is used to monitor the CAN bus to determine whether the PEPS system is normal. The test device and method of the PEPS system can very conveniently test whether the PEPS system is working properly, and after a fault is found during the test, the fault location can be accurately and quickly locked.

[0003] The above patent discloses a test of a traditional PEPS key, which is generally a test of the function, that is, whether the PEPS function is normal, but does not test the field strength consistency of the PEPS. The field strength consistency affects the positioning accuracy in the PEPS key system, which is crucial to the accurate operation of the PEPS system. No related technology is disclosed in the prior art. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a consistency detection system and method based on the low-frequency field strength of a PEPS key, so as to implement a field strength consistency test on a PEPS key.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a consistency detection system based on the low-frequency field strength of a PEPS key, comprising a Holm-Hertz coil and a PEPS key to be tested, wherein the PEPS key and the Holm-Hertz coil are both arranged in a shielding box, and the Holm-Hertz coil is driven to emit magnetic fields in three directions respectively, and the three low-frequency antennas XYZ of the PEPS key receive the corresponding magnetic field signals and collect the corresponding magnetic field strengths sensed, and then the magnetic field strength signals emitted by the PEPS module are collected, and the upper computer analyzes the received magnetic field strength signals in three directions emitted by the PEPS key to obtain field strength data of three channels.

[0006] The Holm Hertz coil is arranged inside the shielding box, and its three-dimensional antenna generates magnetic fields that are equal in three directions; the PEPS key is arranged inside the shielding box and is located at the center of the magnetic field of the Holm Hertz coil.

[0007] The three low-frequency antennas of the PEPS key correspond one to one with the three directions of the Holm-Hertz coil antenna. Only one Holm-Hertz coil antenna is driven at the same time to generate a stable magnetic field in one direction corresponding to one of the low-frequency antennas of the PEPS key for reception.

[0008] The detection system also includes a baseband signal generator, a waveform signal generator, and a channel switching module; the baseband signal generator and the waveform signal generator are used to generate low-frequency data and a carrier signal output to the Holm Hertz coil, the output end of the baseband signal generator is connected to the waveform signal generator, and the output end of the waveform signal generator switches the driving signal to the antenna corresponding to the Holm Hertz coil through the channel switching module.

[0009] The detection system also includes a host computer, in which host computer software runs. The host computer software is used to send drive control signals to the baseband signal generator, the waveform signal generator and the channel switching module respectively, so as to control the operation of the baseband signal generator, the waveform signal generator and the channel switching module respectively.

[0010] The PEPS key receives the low-frequency signal through the low-frequency antenna, collects and obtains the field strength signal, and sends the corresponding high-frequency signal through the high-frequency antenna; a high-frequency signal receiver is arranged in the shielding box, and the host computer obtains the corresponding field strength signal by acquiring the signal in the high-frequency signal receiver.

[0011] The high-frequency signal receiver is configured to receive a high-frequency signal and convert it into a CAN signal. The output end of the high-frequency signal receiver is connected to a CAN communication module outside the shielding box to transmit the signal to the CAN communication module outside the shielding box. The host computer is connected to the CAN communication module to obtain a CAN signal corresponding to the high-frequency signal. The host computer software in the host computer parses the CAN signal and obtains a field strength signal.

[0012] A consistency detection method based on low-frequency field strength of a PEPS key comprises arranging a PEPS key and a Holm-Hertz coil in a shielding box, driving the Holm-Hertz coil to respectively emit magnetic fields in three directions and having three low-frequency antennas XYZ of the PEPS key receive corresponding magnetic field signals and collect and sense corresponding magnetic field strengths, then collecting magnetic field strength signals emitted by a PEPS module, having a host computer analyze the received magnetic field strength signals in three directions emitted by the PEPS key to obtain field strength data of three channels, and analyzing and judging consistency based on the received field strength data of the three channels.

[0013] The three low-frequency antennas of the PEPS key correspond to the three directions of the Holm-Hertz coil antenna one by one. Only one Holm-Hertz coil antenna is driven at the same time to generate a stable magnetic field in one direction corresponding to one of the low-frequency antennas of the PEPS key for reception.

[0014] The host computer software drives the baseband signal generator and the waveform signal generator to generate a sinusoidal baseband signal which acts on the Holm Hertz coil through channel switching. The host computer software drives the channel switching to select an antenna in one direction of the Holm Hertz coil in which the sinusoidal baseband signal acts.

[0015] After receiving the low-frequency data and magnetic field generated by the Holm-Hertz coil, the PEPS key sends the field strength data in the form of a high-frequency signal through the high-frequency antenna of the PEPS key. The upper computer software establishes a connection with the high-frequency receiver through CAN communication and acquires the field strength data through the high-frequency receiver. The upper computer software analyzes the field strength data of the three channels output by the PEPS key obtained through CAN communication and determines the field strength consistency result.

[0016] The advantages of the present invention are: simple and reliable implementation of field strength consistency test for PEPS keys, low hardware cost, and convenient test operation; the field strength value can be used to check whether the matching of the low-frequency circuit is correct, and it can also be used to verify the consistency of the field strength value after the key is low-frequency calibrated, and it has strong versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The following is a brief description of the contents expressed in the drawings of the present invention and the symbols in the drawings:

[0018] Figure 1 This is a schematic diagram of the principle of the key field strength consistency detection system of the present invention;

[0019] Figure 2 The diagram is a schematic diagram of the interface circuit of the low-frequency antenna of the key of the present invention. DETAILED DESCRIPTION

[0020] The specific implementation of the present invention will be further explained in detail below by describing the optimal embodiment with reference to the accompanying drawings.

[0021] The main purpose of this embodiment is to realize the consistency detection of the low-frequency field strength of the PEPS key. The field strength consistency is determined by detecting the low-frequency field strength signal of the PEPS key. Based on the field strength consistency, the matching of the low-frequency circuit is checked to see if it is correct. It can also be used to verify the consistency of the field strength value after the key is low-frequency calibrated. It is used for factory detection or development detection and verification of PEPS keys. The specific scheme is as follows:

[0022] like Figure 1 As shown, it is a schematic diagram of the electrical system architecture corresponding to a consistency detection system based on the low-frequency field strength of a PEPS key, including a Holm Hertz coil, a PEPS key to be tested, a high-frequency receiver, a CAN communication module, a baseband signal generator, a waveform signal generator, a channel switching module, a host computer and host computer software, and a shielding box, wherein the PEPS key and the Holm Hertz coil are both arranged in the shielding box, and the PEPS key has three built-in low-frequency antennas, which are three low-frequency antennas perpendicular to each other. When the PEPS key is in use, the low-frequency signal emitted by the base station in the vehicle forms a vector electromagnetic field around the vehicle, and the three antennas of the key will excite a current limit. PEPS converts the excitation current through the three low-frequency antennas into a voltage, and the AD signal representing the magnitude of the magnetic field strength is obtained after AD sampling by the MCU control unit of the PEPS, and then the high-frequency antenna is driven by the PEPS control unit to emit a magnetic field strength signal in the form of a high-frequency signal. This signal can locate the position of the PEPS key, and the base station in the vehicle can control the unlocking of the door according to the position represented by the magnetic field strength of the PEPS key. Figure 2 The figure shows the schematic diagram of the three low-frequency antennas of the PEPS key, and different magnetic field signals are obtained through the three low-frequency antennas. Based on the working principle of PEPS, since the PEPS key has three antennas, namely the X-axis, Y-axis, and Z-axis antennas, the Holm Hertz coil can generate magnetic fields in three directions, corresponding to the XYZ-axis low-frequency antennas of the PEPS key. The Holm Hertz coil is set inside the shielding box, and its three-dimensional antenna generates equal magnetic fields in three directions; the PEPS key is set inside the shielding box and is at the center of the magnetic field of the Holm Hertz coil.

[0023] By driving the Holm-Hertz coil to emit magnetic fields in three directions respectively, the XYZ three low-frequency antennas of the PEPS key receive the corresponding magnetic field signals and collect the corresponding magnetic field strength. Then, by collecting the magnetic field strength signal emitted by the PEPS module, the upper computer analyzes the received magnetic field strength signals in three directions emitted by the PEPS key to obtain the field strength data of the three channels.

[0024] The three low-frequency antennas of the PEPS key correspond to the three directions of the Helmholtz coil antenna one by one. Only one Helmholtz coil antenna is driven at the same time to generate a stable magnetic field in one direction, which is received by one of the low-frequency antennas of the PEPS key. When driving and controlling, the antennas of the Helmholtz coils corresponding to the X, Y, and Z axes of the PEPS key are controlled in turn to generate magnetic fields, which are then acquired by the low-frequency antennas of the X, Y, and Z axes of the PEPS key. Then, the high-frequency signals output by the PEPS key corresponding to the X, Y, and Z axes are collected respectively, and the field strength data corresponding to the three high-frequency signals are received and analyzed in turn. The field strength data corresponding to the three high-frequency signals can be compared and analyzed to obtain consistent results.

[0025] The Helmholtz coil is set in the shielding box to generate magnetic field signals in three directions corresponding to the low-frequency antenna of the PEPS key. The magnetic field signal in each direction corresponds to a low-frequency antenna of the PEPS key. Therefore, it is necessary to control the operation of the Helmholtz coil and select the working state of different antennas in the Helmholtz coil in turn; therefore, in this scheme, different channels are switched through the channel switching module, and for this purpose, a baseband signal generator, a waveform signal generator, and a channel switching module can be used to achieve this; wherein the baseband signal generator and the waveform signal generator are used to generate low-frequency data and carrier signals output to the Holmholtz coil, and the output end of the baseband signal generator is connected to the waveform signal generator, and the output end of the waveform signal generator switches the driving signal to the antenna corresponding to the Holmholtz coil through the channel switching module. The sinusoidal carrier signals generated by the baseband signal generator and the waveform signal generator are loaded on the antennas of different Helmholtz coils through the channel switching module, respectively, so that the magnetic field signals corresponding to the XYZ antennas of the PEPS key can be generated according to the requirements. The channel switching module can be implemented by a switch, and the sinusoidal carrier signal can be controlled by the switch to be sent to different Helmholtz coil antennas.

[0026] In this scheme, the host computer is the core component of consistency judgment, which is used to control the parameters of the sine wave signal output to the Helmholtz coil and receive and analyze the field strength signals collected by different low-frequency antennas output by the PEPS key; that is, the host computer is used as the core control component, and the host computer has built-in host computer software and corresponding peripherals such as display screens, and the display screens and other peripherals are used to input control parameters, display collected parameters, and analyze and process results. The host computer software runs in the host computer, and the host computer software is used to send drive control signals to the baseband signal generator, the waveform signal generator and the channel switching module respectively, and is used to control the work of the baseband signal generator, the waveform signal generator and the channel switching module respectively. That is, the host computer software can drive and control the parameters of the sine wave signal formed by the baseband signal generator and the waveform signal generator, and can adjust the parameters such as the amplitude and frequency of the sine carrier signal manually or automatically. The drive signal sent to the channel switching module can adjust the channel of the sine carrier signal sent to the Helmholtz coil, thereby achieving the generation of different magnetic fields.

[0027] To achieve the detection of field strength consistency, it is necessary to collect the field strength signals corresponding to the signals of the three different low-frequency antennas XYZ output by the PEPS key and send them to the host computer for analysis. Therefore, the PEPS key receives the low-frequency signal through the low-frequency antenna and collects the field strength signal and sends the corresponding high-frequency signal through the high-frequency antenna; a high-frequency signal receiver is set in the shielding box, and the host computer obtains the corresponding field strength signal by acquiring the signal in the high-frequency signal receiver. The high-frequency receiver is set at the high-frequency receiving end. In order to avoid interference with the CAN communication method to read and acquire the signal, the high-frequency signal receiver is configured to receive the high-frequency signal and convert it into a CAN signal. The output end of the high-frequency signal receiver is connected to the CAN communication module outside the shielding box to transmit the signal to the CAN communication module outside the shielding box. The host computer is connected to the CAN communication module to obtain the CAN signal corresponding to the high-frequency signal. The host computer software in the host computer parses the CAN signal and obtains the field strength signal.

[0028] In this embodiment, a shielding box is used to avoid interference from other external magnetic field signals, so the Helmholtz coil and the PEPS key are both arranged in the shielding box; the channel switching module switches the sinusoidal carrier signal and connects it to the inside of the shielding box and the Helmholtz coil through a cable; similarly, the high-frequency receiver receives the high-frequency signal and converts it into a CAN signal that is not easily interfered with and transmits it to the host computer.

[0029] The present solution also provides a consistency detection method based on the low-frequency field strength of the PEPS key, including placing the PEPS key and the Holm-Hertz coil in a shielding box, driving the Holm-Hertz coil to respectively emit magnetic fields in three directions and having the three low-frequency antennas XYZ of the PEPS key receive corresponding magnetic field signals and collect and sense corresponding magnetic field strengths, then collecting the magnetic field strength signals emitted by the PEPS module, and having the upper computer analyze the received magnetic field strength signals in three directions emitted by the PEPS key to obtain field strength data of three channels, and analyzing and judging the consistency based on the received field strength data of the three channels.

[0030] The three low-frequency antennas of the PEPS key correspond one to one with the three directions of the Holm Hertz coil antenna. Only one Holm Hertz coil antenna is driven at the same time to generate a stable magnetic field in one direction corresponding to one of the low-frequency antennas of the PEPS key for reception. The baseband signal generator and the waveform signal generator are driven by the host computer software to generate a sinusoidal baseband signal that acts on the Holm Hertz coil through channel switching. The host computer software drives the channel switching to select the sinusoidal baseband signal to act on the antenna in one direction of the Holm Hertz coil.

[0031] After receiving the low-frequency data and magnetic field generated by the Holm-Hertz coil, the PEPS key sends the field strength data in the form of a high-frequency signal through the high-frequency antenna of the PEPS key. The upper computer software establishes a connection with the high-frequency receiver through CAN communication and acquires the field strength data through the high-frequency receiver. The upper computer software analyzes the field strength data of the three channels output by the PEPS key obtained through CAN communication and determines the field strength consistency result.

[0032] The present invention relates to a verification method based on the consistency of low-frequency field strength of a PEPS key, which can be used for debugging verification of circuit matching of a low-frequency antenna and verification of field strength effect after three-axis calibration. The verification method mainly controls a baseband signal generator through host computer software to generate a low-frequency baseband and carrier signal, loads it onto a sinusoidal carrier signal output by a signal generator, outputs it to a Holm Hertz coil, sends low-frequency data to wake up the key, and the key collects the uniform magnetic field strength value generated by the Holm Hertz coil. By switching the X / Y / Z three channel coils, the field strength values ​​of different channels are collected, and the consistency of the key field strength of the three channels can be judged by the size of the field strength value. It mainly includes host computer control software, a baseband signal generator, a signal generator, a three-axis coil switching device, a Holm Hertz coil, a key, a high-frequency receiver, a CAN communication device, a shielding box, etc. It is mainly used to judge whether the field strength of the X / Y / Z three axes of the key is consistent, and realize the consistency detection of the field strength value of the key at the same point. In order to accurately locate the position information of the key inside and outside the car, the consistency of the field strength of the key at the same point is very high. The low-frequency field strength consistency is poor due to the impedance difference of the hardware circuit of the circuit matching of the low-frequency antenna, the deviation of the capacitance and resistance, etc. The consistency detection device and method of this scheme can check whether the matching of the low-frequency circuit is correct through the field strength value, and can also be used to detect the consistency of the field strength value after the key low-frequency calibration.

[0033] The present invention uses software to control the device to simulate and generate low-frequency data and carrier waves, and the high-frequency receiving end receives the field strength value and feeds it back to the host computer, and the consistency of the field strength value is judged by the host computer software.

[0034] In view of the increasing popularity of smart car keys, the consistency of low-frequency field strength needs to be improved for the accuracy of field strength positioning. The baseband signal generator and waveform signal generator are controlled by software, and the signal generator generates a sinusoidal baseband signal. The host computer controls the switching of the drive signal of the X / Y / Z 3 axes, and the Helmholtz coil generates low-frequency data and field strength. The key feeds back the field strength signal to the receiving controller, and then feeds back to the host computer for processing through CAN. The specific implementation plan is as follows:

[0035] First, the host computer controls the baseband signal generator and the waveform signal generator. The signal generator generates a sinusoidal carrier signal. The driving signals of the three channels X / Y / Z are switched through the switching device. The Helmholtz coils send out low-frequency data and generate magnetic fields respectively.

[0036] Secondly, after the key senses the signal from the Helmholtz coil, it will collect the sensed magnetic field strength and send the magnetic field strength signal to the high-frequency receiver through high frequency. The high-frequency receiver analyzes the high-frequency data and sends the field strength signal to the host computer through CAN communication. The host computer analyzes the consistency of the field strength data. The switching device can realize the detection of field strength data of 3 channels.

[0037] like Figure 1 As shown, it is a structural block diagram of the detection device of the low-frequency field strength consistency of the key: the baseband signal generator, the signal generator, and the channel switching device are controlled by the host computer software to output the low-frequency data and the carrier to the Holm Hertz coil. After the key receives the low-frequency data, it collects the field strength signal and sends it to the high-frequency receiving end through the high frequency. The host computer reads the field strength value through CAN communication to detect the consistency of the low-frequency field strength data.

[0038] Obviously, the specific implementation of the present invention is not limited to the above-mentioned methods. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, they are all within the protection scope of the present invention.

Claims

1. A consistency detection system based on the low-frequency field strength of a PEPS key, characterized by: The method comprises a Holm-Hertz coil and a PEPS key to be tested, wherein the PEPS key and the Holm-Hertz coil are both arranged in a shielding box, and the Holm-Hertz coil is driven to respectively emit magnetic fields in three directions, and the three low-frequency antennas XYZ of the PEPS key receive corresponding magnetic field signals and collect and sense corresponding magnetic field strengths, and then the magnetic field strength signals emitted by the PEPS module are collected, and the upper computer analyzes the received magnetic field strength signals in three directions emitted by the PEPS key to obtain field strength data of three channels.

2. A consistency detection system based on low-frequency field strength of a PEPS key as claimed in claim 1, characterized in that: The Holm Hertz coil is arranged inside the shielding box, and its three-dimensional antenna generates magnetic fields that are equal in three directions; the PEPS key is arranged inside the shielding box and is located at the center of the magnetic field of the Holm Hertz coil.

3. A consistency detection system based on low-frequency field strength of a PEPS key as claimed in claim 1 or 2, characterized in that: The three low-frequency antennas of the PEPS key correspond one to one with the three directions of the Holm-Hertz coil antenna. Only one Holm-Hertz coil antenna is driven at the same time to generate a stable magnetic field in one direction corresponding to one of the low-frequency antennas of the PEPS key for reception.

4. A consistency detection system based on low-frequency field strength of a PEPS key as claimed in claim 1 or 2, characterized in that: The detection system also includes a baseband signal generator, a waveform signal generator, and a channel switching module; the baseband signal generator and the waveform signal generator are used to generate low-frequency data and a carrier signal output to the Holm Hertz coil, the output end of the baseband signal generator is connected to the waveform signal generator, and the output end of the waveform signal generator switches the driving signal to the antenna corresponding to the Holm Hertz coil through the channel switching module.

5. A consistency detection system based on low-frequency field strength of a PEPS key as claimed in claim 4, characterized in that: The detection system also includes a host computer, in which host computer software runs. The host computer software is used to send drive control signals to the baseband signal generator, the waveform signal generator and the channel switching module respectively, so as to control the operation of the baseband signal generator, the waveform signal generator and the channel switching module respectively.

6. A consistency detection system based on low-frequency field strength of a PEPS key as described in any one of claims 1 to 5, characterized in that: The PEPS key receives the low-frequency signal through the low-frequency antenna, collects and obtains the field strength signal, and sends the corresponding high-frequency signal through the high-frequency antenna; a high-frequency signal receiver is arranged in the shielding box, and the host computer obtains the corresponding field strength signal by acquiring the signal in the high-frequency signal receiver.

7. A consistency detection system based on low-frequency field strength of a PEPS key as described in any one of claims 1 to 5, characterized in that: The high-frequency signal receiver is configured to receive a high-frequency signal and convert it into a CAN signal. The output end of the high-frequency signal receiver is connected to a CAN communication module outside the shielding box to transmit the signal to the CAN communication module outside the shielding box. The host computer is connected to the CAN communication module to obtain a CAN signal corresponding to the high-frequency signal. The host computer software in the host computer parses the CAN signal and obtains a field strength signal.

8. A consistency detection method based on the low-frequency field strength of a PEPS key, characterized in that: The PEPS key and the Holm-Hertz coil are both placed in a shielding box. The Holm-Hertz coil is driven to emit magnetic fields in three directions respectively, and the three low-frequency antennas XYZ of the PEPS key receive the corresponding magnetic field signals and collect the corresponding magnetic field strength. Then, the magnetic field strength signal emitted by the PEPS module is collected, and the upper computer analyzes the received magnetic field strength signals in three directions emitted by the PEPS key to obtain the field strength data of the three channels. The consistency is analyzed and judged based on the received field strength data of the three channels.

9. A consistency detection method based on low-frequency field strength of a PEPS key as claimed in claim 8, characterized in that: The three low-frequency antennas of the PEPS key correspond to the three directions of the Holm-Hertz coil antenna one by one. Only one Holm-Hertz coil antenna is driven at the same time to generate a stable magnetic field in one direction corresponding to one of the low-frequency antennas of the PEPS key for reception. The host computer software drives the baseband signal generator and the waveform signal generator to generate a sinusoidal baseband signal which acts on the Holm Hertz coil through channel switching. The host computer software drives the channel switching to select an antenna in one direction of the Holm Hertz coil in which the sinusoidal baseband signal acts.

10. A consistency detection method based on low-frequency field strength of a PEPS key as claimed in claim 8 or 9, characterized in that: After receiving the low-frequency data and magnetic field generated by the Holm-Hertz coil, the PEPS key sends the field strength data in the form of a high-frequency signal through the high-frequency antenna of the PEPS key. The upper computer software establishes a connection with the high-frequency receiver through CAN communication and acquires the field strength data through the high-frequency receiver. The upper computer software analyzes the field strength data of the three channels output by the PEPS key obtained through CAN communication and determines the field strength consistency result.

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