TWM617752U - Automatic test system for electric field simulation of three-board line field intensity interference of automotive electronic parts - Google Patents

Abstract

An automatic test system for electric field simulation of three-board line field intensity interference of automotive electronic parts is used to detect a device to be tested. The system includes a terminal unit with a computer host and software to control a signal generator, set a power amplifier, a directional coupler, and an attenuator, and can read a dual-channel power meter and a single-channel power meter. Calculate the average field strength, midpoint power, impedance, etc. to form a field strength meter, and the software calibrates a three-board wire fixture according to the field strength meter; the software receives the change in the output of the device under test that is subjected to electromagnetic interference, And along with the output, an induced electromagnetic intensity is transmitted to the host computer to determine the test status of the device under test, and then the test result of the device under test and the interference signal are used to determine whether the interference signal affects the test result of the device under test. The ability of the device under test to resist interference in the signal.

Description

Automatic test system for electric field simulation of three-board line field intensity interference of automotive electronic parts

This creation is related to a test system for automotive electronic parts, especially an automatic test system for electric field simulation of three-board line field intensity interference of automotive electronic parts.

In recent years, with the rapid development of technology and technology, the global automobile industry has become more and more dependent on in-vehicle electronics, which has led to the rapid growth of in-vehicle electronics. ) The test is required to have more electromagnetic susceptibility (EMS) test items. The electromagnetic tolerance detection method is to simulate the transmission of external disturbance energy to the object under test to determine the endurance capability of the object under test. Generally speaking, different disturbance energies must have different testing methods, and an appropriate coupling method can be selected to smoothly blend the energy to the object to be tested, so as to verify whether the automotive electronic products can work normally under the effect of electromagnetic interference. Electromagnetic tolerance/sensitivity reflects the ability of the product under test to resist interference, and is related to the overall quality and safety of the car in the future. The electromagnetic tolerance/sensitivity test of the automobile was mainly carried out by manually operating the test instrument in the past. Because the test system cannot respond immediately to the performance of the DUT under the interference state, and requires human intervention to observe the test state of the DUT, and the test operation must cooperate with regulations and procedures to perform multiple operations on one or more instruments. Repeated operations for several times, sometimes it is necessary to record the experimental data of multiple instruments, which is undoubtedly a very heavy work for the experimenter, the efficiency is low, and there is a possibility that the test may lose accuracy and automaticity.

In order to improve the above-mentioned problems, the main purpose of this creation is to provide a test system that uses software to monitor the output of a device under test that has been subjected to electromagnetic interference through the three-board wire fixture test, and generates an induced electromagnetic intensity transmission with the output through a field intensity meter. Receive records for a terminal unit to determine the test status of the device under test, thereby improving the accuracy and reliability of the test. Another purpose of this creation is to provide a test system that realizes automatic control of the test process according to test standards, and effectively completes the electromagnetic tolerance/sensitivity test program of automotive electronic parts that simulates the three-board line field strength interference test. In order to achieve the above purpose, this creation provides an automatic test system for electric field simulation of three-plate line field strength interference of automotive electronic parts, which is applied to a device under test with a transmitting antenna, which includes: a signal generator, a power amplifier, and a Directional coupler, an attenuator, a power meter, a three-board wire fixture, a field strength meter and a terminal unit. Wherein, the signal generator generates a radio frequency interference signal; the power amplifier receives the radio frequency interference signal, and amplifies the radio frequency interference signal into a high-power interference signal and transmits it through a directional coupler and an attenuator; the The power meter includes a dual-channel power meter and a single-channel power meter respectively connected to the directional coupler and the attenuator for measuring the high-power interference signal passing through the directional coupler and measuring the passing through the attenuator An electromagnetic field strength signal after attenuation; one end of the three-board line fixture is connected to the directional coupler to input the high-power interference signal and the other end is connected to the attenuator, the three-board line fixture is connected to the device under test through the transmitting antenna An electromagnetic interference is applied and the electromagnetic field strength signal emitted by the transmitting antenna can be monitored; the field strength meter receives the three-board wire fixture to monitor the electromagnetic field strength signal, and the field strength meter is used to measure an output of the device under test An induced electromagnetic intensity generated by the change; the terminal unit, which is electrically connected to the signal generator and the power amplifier, can read the dual-channel power meter and the single-channel power meter, and receive the induced electromagnetic intensity, and The test state of the device under test is determined according to the received electromagnetic intensity. In one embodiment, the aforementioned terminal unit includes a computer with a control unit and software. In one embodiment, the aforementioned terminal unit is used to control the signal generator, set the power amplifier, the directional coupler and the attenuator, and calculate an average field strength, a midpoint power, and impedance. In one embodiment, the aforementioned directional coupler is integrated in the power amplifier, and the high-power interference signal is connected to the transmitting antenna through the directional coupler. In one embodiment, one end of the aforementioned single-channel power meter is connected to the terminal unit through a bus bar, and the other end is connected to the output end of the three-board wire fixture to measure the intensity of the interference signal generated by the power amplifier, and The intensity value of the interference signal is transmitted to the control unit. In one embodiment, the aforementioned directional coupler has an input terminal, a pair of coupling terminals, and an output terminal. The input terminal receives the high-power interference signal output by the power amplifier, and the coupling terminals output a small portion of the high-power interference signal To the power meter, the remaining high-power interference signal output from the output terminal passes through the attenuator. In one embodiment, the aforementioned dual-channel power meter has dual input channels for simultaneously measuring the forward power of the power amplifier and transmitting the reverse power to the terminal unit to calculate the forward power based on the high-power interference signal received. And the difference of the reverse power. In one embodiment, the aforementioned terminal unit adjusts an output level of the signal generator according to the deviation of the induced electromagnetic strength from a preset electromagnetic strength so that the induced electromagnetic strength reaches the preset electromagnetic strength value. In this way, this creation has the following beneficial effects. The system includes a terminal unit with a computer host and software for controlling a signal generator, setting a power amplifier, a directional coupler, and an attenuator, and can read a pair of Channel power meter, a single-channel power meter, calculate the average field strength, midpoint power, impedance, etc. to form a field strength meter, and use the software to calibrate a three-board wire fixture according to the field strength meter; Electromagnetic interference changes in the output of the device under test (such as light or sound), and along with the output, an induced electromagnetic intensity is transmitted to the computer host to determine the test status of the device under test, and then to detect the device under test test The result and the interference signal determine whether the interference signal affects the test result of the device under test, and finally obtain the anti-interference ability of the device under test in the signal.

，最後依據如下公式，即可計算得「平均中點功率」。 E _AVG=

步驟三：如第5圖所示，平均中點功率校正方案說明：本校正方式與前述定功率校正方案的功率計讀取/記錄等操作皆相似故不贅述之，其差異在於，必須先算出平均場強，再計算中點功率係以中點功率達成平均中點功率值為主要，是依據如下公式得到： P _mid=

當得到後，進而完成所有頻率點的平均中點功率校正，最後，再完成平均中點功率校正。 步驟四：如第6圖所示，三板線測試方案說明：本校正方式主要在於，待測裝置設置於該三板線治具上後，依照校正時所得各頻點阻抗值Z(f)，套用公式A1 如下： E _v(f) =

算出符合Ev(f) 場強所需的中點功率(Pmid(f))，先參考校正得到SG Level 值輸出後，調整SG level 再使實際中點功率(Pmid (f)符合要求。也就是，將訊號產生器產生的射頻干擾訊號調節至所述校準時得到的訊號產生器的輸出值；按指定方向和單位位移移動天線和待測裝置的位置進行測試，並即時獲取待測裝置的變化狀態參數；根據該待測裝置的變化狀態參數得出測試評估結果。 因此，前述校正及測試過程中每個階段步進均需進行誤差測試並記錄，並根據該等誤差測試以該終端單元8的測試軟體82來進行多次校正以符合法規定定義，最後，才進行可實現在電磁場干擾過程中的電磁誤差測試(即三板線測試)，進而實現校正若無存在大於指定值的功率偏差值，则校准完成。測試時，根據設置的頻率點步進值，對測試下一頻點進行相同測試，直至測試所有頻率點均測試完成，待所有頻率點測試結束後，再通過單一頻率點測試來確定該頻率點是否為待測裝置開始出現異常。根據觀察並記錄下的被測裝置在異常頻率點和在其它頻率點的預設電平值，當完成所有頻率點的測試，對測試獲得資料進行處理，最後檢視待測裝置是否出現任何異狀，若無，則產出測試報表，若有，則待測裝置列為需加以修改清單。在測試過程中，讀入功率計、場強計的值時，均連續讀取3 次，取平均值，以提高測試精度。 據此，藉由上述構件的組合實施，參閱如圖1至圖6 所示，本創作利用軟體82根據場強計7去校正一三板線治具6，以及軟體82接收被施加電磁干擾的待測裝置91的輸出(例如燈光或聲音)的變化，並隨著該輸出產生一感應電磁強度傳至該電腦主機81判斷該待測裝置91是否受特定頻率的平擾訊號干擾等測試狀態，及判斷該待測裝置91 在該射頻干擾訊號的最大干擾量及最小干擾量時的輸出表現，據以檢測出該待測裝置測試結果與該干擾訊號判斷干擾訊號是否影響待測裝置91測試結果，最終獲得待測裝置在訊號抗干擾的能力，進而提昇測試的準確性。 以上已將本創作做一詳細說明，惟以上所述者，僅為本創作之一較佳實施例而已，當不能限定本創作實施之範圍。即凡依本創作申請範圍所作之均等變化與修飾等，皆應仍屬本創作之專利涵蓋範圍。 The above-mentioned purpose of this creation and its structural and functional characteristics will be described based on the preferred and specific embodiments of the accompanying drawings. Please refer to Figure 1 for a block diagram of the creation test system; Figure 2 is a block diagram of the directional coupler in Figure 1; Figure 3 is a block diagram of the creation constant field strength correction; Figure 4 is a creation constant power calibration block Schematic diagram; Figure 5 is a schematic diagram of the creation average midpoint power correction block diagram; Figure 6 is a schematic diagram of the creation three-board line test block diagram. As shown in the figure, the authoring test system is used to measure and calibrate a device under test 91. The device under test 91 can be connected to a transmitting antenna 92. The device under test 91 is, for example, a car lamp or car audio. The measuring device 91 and the transmitting antenna 92 are electrically connected to a power source to provide a voltage for normal operation. The test system includes: a signal generator 1, a power amplifier 2, a directional coupler 3, an attenuator 4, a power meter 5 with a dual-channel power meter 51 and a single-channel power meter 52, and a three-board wire fixture 6. A strong plan 7, and a terminal unit 8 with a computer host 81 and software 82. The structure and interrelationship of the aforementioned systems are detailed as follows. The signal generator 1 is controlled by the terminal unit 8 to generate a radio frequency interference signal for simulating the source of the interference signal. The frequency range of the radio frequency interference signal can be adjusted, for example, 1 MHz to 400 MHz. The power amplifier 2 is connected to the signal generator 1. As the power is defined by law, it is necessary to use an amplifier to generate interference signals. That is, the power amplifier 2 receives the radio frequency interference signal generated by the signal generator 1 and amplifies the radio frequency interference signal into a high-power interference signal. The high-power interference signal can be transmitted to the single-channel power meter 52 of the power meter 5 via the directional coupler 3 and the attenuator 4 to simulate an electromagnetic interference source and then apply an electromagnetic interference to the device under test 91. The directional coupler 3 may be integrated in the power amplifier 2 to become a part of the power amplifier 2, or it may be a stand-alone entity. As shown in Figure 2, the directional coupler 3 has an input terminal 131, an output terminal 132, and a pair of coupling terminals 133a, 133b. The input terminal 131 receives the high-power interference signal output by the power amplifier 12. The terminals 133a and 133b output a small part of the high-power interference signal to the dual-channel power meter 51 of the power meter 5, and the output terminal 132 outputs the remaining high-power interference signal to the attenuator via the three-board wire fixture 6. 4 Perform attenuation. Specifically, since the power amplified by the power amplifier 2 is relatively large and easily exceeds the power measurement range, it is necessary to install a bidirectional directional coupler 3 and calculate the value through the software 82 of the terminal unit 8 to comply with the monitoring. The aforementioned directional coupler 3 connects the transmitting antenna 92 to connect the high-power interference signal to the transmitting antenna 92 to apply electromagnetic interference to the device under test 91. The attenuator 4 is used as the front end of the single-channel power meter 52 of the power meter 5 to reduce the amplitude or power of the high-power interference signal to prevent the high-power interference signal from being at the front end of the single-channel power meter 52 Damage is caused to protect the single-channel power meter 52 of the power meter 5. One end of the attenuator 4 is connected to an output end 62 of the three-board wire fixture 6. The power meter 5 is connected to the directional coupler 3 and the attenuator 4 by the dual-channel power meter 51 and the single-channel power meter 52, respectively, and the dual-channel power meter 51 and the single-channel power meter 52 can pass through A bus bar is connected to the terminal unit 8. Among them, the dual-channel power meter 51 is used to measure (ie, read and record) the intensity of the high-power interference signal transmitted through the directional coupler 3, and can output and transmit the value of the high-power interference signal intensity. To the terminal unit 8; the single-channel power meter 52 is used to measure an electromagnetic field strength signal monitored by the three-board wire fixture 6 and attenuated by the attenuator 4. Specifically, the aforementioned dual-channel power meter 51 has dual input channels, and the dual input channels can be connected to the directional coupler 3 via a power probe for measuring the intensity of the high-power interference signal transmitted through the directional coupler 3 , And simultaneously measure (ie, read and record) the "forward power" and "reverse power" of the power amplifier 2 based on the received high-power interference signal and transmit them to the terminal unit 8, and through the terminal The software 82 of the unit 8 reads and calculates the difference between the forward power and the reverse power to reflect the load status of the power amplifier 2, and the terminal unit 8 is less than a set according to the difference between the forward power and the reverse power When the value is set, it is determined that the power amplifier 2 is in a no-load state, and then the output of the signal generator 1 is automatically controlled to drop to the initial value to protect the power amplifier 2. Specifically, one end of the aforementioned single-channel power meter 52 can be connected to the terminal unit 8 through a bus bar, and the other end is connected to the output end 62 of the three-board wire fixture 6 through the attenuator 4, which facilitates the measurement of the power amplifier 2 The intensity value of the generated interference signal is transmitted to the terminal unit 8 and corrected by the software 82. Specifically, as shown in Fig. 3, for the aforementioned power meter 5, when a high-power interference signal is fed to the power meter 5 through a power probe, the terminal unit 8 control software 82 reads the value of the power meter 5 and monitors Sensing changes in the intensity of high-power interference signals. When the intensity of the induced high-power interference signal deviates from the preset signal strength, adjust the output level of the signal generator 1 until the intensity of the induced high-power interference signal monitored by the power meter 5 reaches the preset signal strength value. When the actual forward power of the power amplifier is a predetermined multiple (for example, 3 times) of the predetermined forward power and still does not reach the predetermined level value, the adjustment is stopped and the test at the frequency point is ended. For the three-board wire jig 6, one input end 61 is connected to the directional coupler 3 to input the high-power interference signal, and the other output end 62 is connected to the attenuator 4, and the three-board wire jig 6 is between the plates The device under test 91 is provided and an electromagnetic interference is applied to the device under test 91 through the transmitting antenna 92. The three-plate wire jig 6 is used to monitor the electromagnetic field strength signal emitted by the transmitting antenna 92. The electromagnetic field strength signal emitted by the transmitting antenna 92 is fed back to the field meter 7. Specifically, the three-plate line fixture 6 (Triplate, referred to as TPL for short) is an open transmission line composed of three plates. The outer plate is at ground potential and is connected to the shielding layer of the coaxial cable that feeds the signal. In this embodiment, the three-plate wire fixture 6 is used as an open transverse electromagnetic unit, which is a broadband parallel plate structure, which mainly has a grounded top outer plate and a bottom outer plate, and an isolated center plate. When the high-power interference signal is input to the input terminal 61, an electromagnetic field will be generated between the boards, and the output terminal is terminated with a 50Ω load. That is, the test function is to use the transmitting antenna 92 to radiate disturbance energy to form a uniform electromagnetic field around the device under test 91, which facilitates the subsequent test mode of the three-board wire fixture 6. The field strength meter 7 can receive the three-board wire fixture 6 through an optical fiber to monitor the electromagnetic field strength signal emitted by the transmitting antenna (used to simulate electromagnetic interference to the device under test), and the field strength meter 7 is used to measure An induced electromagnetic intensity generated by an output change of the device under test 91 and the measured induced electromagnetic intensity are transmitted to the computer host 81 of the terminal unit 8. Specifically, the field strength meter 7 is an instrument that can measure the electric field intensity emitted by the transmitter (ie, radio frequency transmitting antenna). After it is tuned to a specific frequency, the electric field intensity at the corresponding position can be measured and the field intensity probe can be used to measure the electric field intensity. The monitored electromagnetic field strength signal is fed back to the host computer 81 of the terminal unit 8 through an optical fiber, so that the radiation of the antenna can be accurately measured. Among them, the function of the field intensity probe is to sense the electromagnetic intensity near the device under test. Specifically, as shown in Fig. 3, if electromagnetic interference signals of different frequencies are applied to the device under test 91, when the field strength correction scheme is determined, the field strength meter 7 reads the induction in the three-plate wire fixture 6 The electromagnetic strength is mainly based on reaching the target field strength. The terminal unit 8 has the computer host 81 and software 82. In this embodiment, the computer host 81 may have a control unit and a detector; the terminal unit 8 is used to communicate with the signal generator 1 and the power amplifier 2 Electrically connect and control the signal generator 1, set the power amplifier 2, the directional coupler 3, the attenuator 4, and the dual-channel power meter 51 and single-channel power meter 52 that can read the power meter 5, and calculate Average field strength, midpoint power, impedance, etc., and the terminal unit 8 can receive the induced electromagnetic strength from the field meter 7, and the control unit receives a deviation of the induced electromagnetic strength from a preset electromagnetic strength. Value, an output level of the signal generator 1 is adjusted so that the induced electromagnetic intensity reaches the preset electromagnetic intensity value, which is used to determine the test state of the device under test 91. Specifically, as shown in Fig. 3, if electromagnetic interference signals of different frequencies are applied to the device under test 91, it will be calibrated many times before the three-board wire fixture 6 is tested, so that the three-board wire fixture 6 is tested Obtain high-quality electromagnetic field strength signals to feed the field meter 7. Specifically, in one implementation, the aforementioned detector may be a light source detector for detecting changes in the output (ie, light source) of the device under test 91 (for example, a car light); or in another implementation, the aforementioned detection The device is a sound detector for detecting changes in the output (that is, sound) of the device under test 91 (for example, audio). The detector is used to detect a change in an output of the device under test 91 subjected to electromagnetic interference to generate a detection signal and output it to the computer host 81. Specifically, the host computer 81 of the terminal unit 8 reads the intensity of the induced electromagnetic signal monitored by the three-board wire fixture 6 of the field strength meter 7 through the software 82, and monitors the change of the intensity of the induced electromagnetic signal. When the intensity of the induced electromagnetic signal deviates from the intensity of a preset electromagnetic signal, adjust an output level of the signal generator 1 until the power meter 5 measures that the intensity of the induced electromagnetic signal reaches the preset electromagnetic signal Strength value. Furthermore, the computer host 81 of the terminal unit 8 receives the detection signal generated by the detector, records the detection signal at the same time, and then determines the test of the device under test 91 (such as a car product) based on the detection signal According to the status, the ability of the device under test 91 (such as a car product) to resist signal interference is detected. Specifically, for example, the device under test 91 is a car light, and the detector detects the light source change of the car light to generate a light source detection signal and output it to the terminal unit 8. The terminal unit 8 records the light source detection signal, and then The light source detection signal determines whether the car light is interfered by a specific frequency interference signal, and the light source performance of the car light at the maximum interference amount and the minimum interference amount of the radio frequency interference signal is determined based on the light source detection signal. The aforementioned automatic correction and test schemes for the intensity of the induced electromagnetic signal monitored by the three-plate line fixture 6, as shown in Figures 3, 4, 5, and 6 are constant field strength correction, constant power correction, and average midpoint power correction. , And a schematic diagram of the three-board line test block. It mainly uses the midpoint power to flatten the field according to the specified field strength to perform calibration to determine the impedance of the three-board line at each test frequency. That is, the field strength of the center line of the triangle at five different positions (such as P1~P5) is measured by the three-board wire fixture 6, the net power entering the triangle (positive direction minus the negative direction) and from the triangle The power from the other end of the polygon will measure three power levels, and the software 82 used for testing will control the computer (or instrument) and continuously adjust the power level to achieve the required test level. In order to save time for each frequency, control the test software to read only forward power readings until the forward power exceeds the required midpoint power. Then, only obtain the forward and reverse power readings until the required midpoint power is exceeded to determine the power level at the midpoint of the three-board wire fixture. This, together with the impedance of the triple metal plate of the three-plate wire jig, is used to determine how much power is required to achieve the specified field strength, and then include the output power to finally reach the required test level, thereby determining that the device under test 91 is applied The electromagnetic field strength value ensures that the power amplifier will not be damaged due to excessive reflected power in this frequency range, which effectively guarantees the smooth progress of the radiation sensitivity test and the safety of the power amplifier. Specifically, referring to Figs. 3 to 6, the above components and structural design are used to test and analyze the relevant experiments, as follows: Step 1: As shown in Fig. 3, the fixed field strength correction scheme is explained: the purpose is to seek first The corresponding impedance value Z(f) of the three-plate wire fixture at each frequency point is obtained, and the Ev field strength formula is inserted to obtain the midpoint power Pmid(f) of the three-plate wire fixture; that is, the radio frequency interference signal of the signal generator Output to the power amplifier 2 for power amplification. The power amplifier 2 transmits through one of the two directions of the directional coupler 3 (the red line in the figure) to the field emitted by the transmitting antenna 92 and read by the field strength meter 7. First, place the field strength meter 7 at the P3 position, measure the power value of each frequency point that meets the field strength, and perform the field strength correction of the frequency point; among them, set the field strength meter at the device under test 91 to monitor the field strength . If electromagnetic interference signals of different frequencies are applied to the device under test 91, the field strength meter 7 reads the induced electromagnetic strength in the third board wire fixture 6 to achieve the target field strength, and then the power meter 5 The forward power, reverse power, and output power read/recorded; when the power amplifier is adjusted multiple times so that the actual forward power is the preset forward power, obtain the value of each specified calibration point within the specified frequency range Forward power value, and calculate the power deviation of each designated calibration point in each designated frequency band according to the preset corresponding forward power standard value, and determine whether there is a power deviation value greater than the designated value, if not; That is, the midpoint power is calculated and obtained. At this time, the frequency point correction is completed, and the field strength correction is completed, and then you can switch to the next constant power correction scheme. Furthermore, if the intensity of the induced high-power interference signal deviates from the preset signal strength, adjust the output level of the signal generator 1 until the intensity of the induced high-power interference signal monitored by the power meter 5 reaches the preset signal strength If the actual forward power of the power amplifier is adjusted to a predetermined multiple (for example, 3 times) of the predetermined forward power and still does not reach the preset level value, the adjustment is stopped and the test at the frequency point is ended. Step 2: As shown in Figure 4, the description of the constant power correction scheme: This correction method is similar to the above-mentioned constant field strength correction scheme for completing frequency point correction, completing field strength correction and other operations, so I will not repeat them. The difference is: After completing the frequency point calibration and completing the field strength correction, proceed to all positions (for example, place the field strength meter 7 at P1, P2, P4, P5, etc.), and measure the frequency points at each position to meet the field strength requirements. Power value, and perform the field strength correction of each frequency point at each position; based on the foregoing method, five constant power correction plan result tables will be presented, so according to the following formula and the 5 constant power correction plan result tables are added to the sum ÷5 is the calculation of "Average Field Strength": E _AVG =

, And finally the "average midpoint power" can be calculated according to the following formula. E _AVG =

Step 3: As shown in Figure 5, the average midpoint power correction scheme description: This correction method is similar to the power meter reading/recording operation of the aforementioned constant power correction scheme, so I will not repeat it. The difference is that it must be calculated first Average field strength, and then calculate the mid-point power system based on the mid-point power to achieve the average mid-point power value, which is obtained according to the following formula: P _mid =

When it is obtained, the average midpoint power correction of all frequency points is completed, and finally, the average midpoint power correction is completed. Step 4: As shown in Figure 6, the description of the three-board line test plan: This calibration method mainly consists in that the device to be tested is installed on the three-board line fixture and applied according to the impedance value Z(f) at each frequency point obtained during calibration. The formula A1 is as follows: E _v (f) =

Calculate the midpoint power (Pmid(f)) required to meet the Ev(f) field strength, first refer to the correction to obtain the SG Level value output, adjust the SG level and then make the actual midpoint power (Pmid (f) meet the requirements. , Adjust the radio frequency interference signal generated by the signal generator to the output value of the signal generator obtained during the calibration; move the antenna and the position of the device under test according to the specified direction and unit displacement to test, and obtain the change of the device under test in real time State parameters; the test evaluation results are obtained according to the change state parameters of the device under test. Therefore, each step of the calibration and testing process needs to be tested and recorded for error, and the terminal unit 8 is used according to the error test The test software 82 is used to perform multiple calibrations to comply with the definition of the law. Finally, the electromagnetic error test (ie three-board line test) that can be realized in the electromagnetic field interference process is carried out, and then the correction is realized if there is no power deviation value greater than the specified value , The calibration is completed. During the test, according to the set frequency point step value, the same test is performed on the next frequency point to be tested until all the frequency points are tested. After all the frequency points are tested, the single frequency point test is passed To determine whether the frequency point is that the device under test is beginning to be abnormal. According to the observed and recorded preset level values of the tested device at the abnormal frequency point and other frequency points, when the test of all frequency points is completed, the test is obtained Process the data, and finally check whether there are any abnormalities in the device under test. If there is no abnormality, a test report will be generated. If there is, the device under test will be listed as a list that needs to be modified. During the test, read in the power meter and field strength When calculating the value, read 3 times in succession and take the average value to improve the test accuracy. According to this, the combination of the above components is implemented, as shown in Figure 1 to Figure 6, this creation uses the software 82 according to the field strength The meter 7 corrects a three-board wire fixture 6, and the software 82 receives the change in the output (such as light or sound) of the device under test 91 that is subjected to electromagnetic interference, and generates an induced electromagnetic intensity along with the output and transmits it to the computer The host 81 judges whether the device under test 91 is interfered by a flat interference signal of a specific frequency and other test conditions, and judges the output performance of the device under test 91 at the maximum interference amount and the minimum interference amount of the radio frequency interference signal, and then detects The test result of the device under test and the interference signal determine whether the interference signal affects the test result of the device under test 91, and finally obtain the anti-interference ability of the signal of the device under test, thereby improving the accuracy of the test. This creation has been described in detail above. However, the above is only a preferred embodiment of this creation, and should not limit the scope of implementation of this creation. That is, all equal changes and modifications made in accordance with the scope of this creation application should still belong to this creation Patent coverage.

1: Signal generator 2: Power amplifier 3: Directional coupler 131: Input 132: output 133a, 133b: coupling end 4: Attenuator 5: Power meter 51: Dual channel power meter 52: Single channel power meter 6: Three-board wire fixture 61: Input 62: output 7: Field strength meter 8: terminal unit 81: computer host 82: Software 91: device under test 92: Transmitting antenna

Figure 1 is a block diagram of the creation and testing system; Figure 2 is a block diagram of the directional coupler in Figure 1; Figure 3 is a schematic diagram of the creation of a fixed field strength correction block; Figure 4 is a schematic diagram of the creation of a constant power calibration block; Figure 5 is a schematic diagram of the creation average midpoint power correction block diagram; Figure 6 is a schematic diagram of the creation of the three-board line test block.

1: Signal generator

2: Power amplifier

3: Directional coupler

4: Attenuator

5: Power meter

51: Dual channel power meter

52: Single channel power meter

6: Three-board wire fixture

61: Input

62: output

7: Field strength meter

8: terminal unit

81: computer host

82: Software

91: device under test

92: Transmitting antenna

Claims (11)

An automatic test system for electric field simulation of three-board line field intensity interference of automotive electronic parts is applied to a device under test with a transmitting antenna. The test system includes: A signal generator generates a radio frequency interference signal; A power amplifier, receiving the radio frequency interference signal, amplifying the radio frequency interference signal into a high-power interference signal and transmitting it through a directional coupler and an attenuator; A power meter, including a dual-channel power meter and a single-channel power meter respectively connected to the directional coupler and the attenuator, for measuring the high-power interference signal passing through the directional coupler and measuring the attenuation An electromagnetic field strength signal of the device; A three-board line fixture, one end of which is connected to the directional coupler to input the high-power interference signal and the other end to the attenuator, the three-board line fixture applies electromagnetic interference to the device under test through the transmitting antenna, and can The electromagnetic field strength signal emitted by the transmitting antenna is monitored; A field strength meter, receiving the electromagnetic field strength signal monitored by the three-board wire fixture, the field strength meter being used to measure an induced electromagnetic strength generated by an output change of the device under test; and A terminal unit, electrically connected to the signal generator and the power amplifier, can read the dual-channel power meter and the single-channel power meter, and receive the induced electromagnetic strength, and determine according to the received induced electromagnetic strength The test status of the device under test. According to claim 1, the electric field simulation three-board line field intensity interference automatic test system of automotive electronic parts, wherein the terminal unit includes a computer host with a control unit and software. According to claim 1 or 2, the electric field simulation three-plate line field strength interference automatic test system of automotive electronic parts, wherein the terminal unit is used to control the signal generator, set the power amplifier, the directional coupler and the attenuator, And calculate an average field strength, a midpoint power, and impedance. The electric field simulation three-plate line field intensity interference automatic test system for automotive electronic parts as described in claim 1, wherein the directional coupler is integrated in the power amplifier, and the high-power interference signal is connected to the transmitter through the directional coupler antenna. According to claim 1, the electric field simulation three-plate line field intensity interference automatic test system of automotive electronic parts, wherein one end of the single-channel power meter is connected to the terminal unit through a bus bar, and the other end is connected to the terminal unit through the attenuator The output terminal of the three-board wire fixture is used to measure the intensity of the interference signal generated by the power amplifier and transmit the intensity value of the interference signal to the terminal unit. The electric field simulation three-plate line field strength interference automatic test system for automotive electronic parts according to claim 1, wherein the directional coupler has an input end, a pair of coupling ends and an output end, and the input end receives the high output of the power amplifier. For power interference signals, the coupling ends output a small portion of high-power interference signals to the power meter, and the output ends output the remaining high-power interference signals through the attenuator. The electric field simulation three-plate line field strength interference automatic test system for automotive electronic parts according to claim 6, wherein the dual-channel power meter has dual input channels for simultaneously measuring the power amplifier based on the high-power interference signal received The forward power and reverse power are transmitted to the terminal unit to calculate the difference between the forward power and the reverse power. According to claim 1, the electric field simulation three-plate line field intensity interference automatic test system of automotive electronic parts, wherein the terminal unit adjusts an output level of the signal generator according to the deviation of the induced electromagnetic intensity from a preset electromagnetic intensity Make the induced electromagnetic intensity reach the preset electromagnetic intensity value. According to claim 1, the electric field simulation three-board line field intensity interference automatic test system for automotive electronic parts, wherein the three-board line fixture has a grounded top outer plate and a bottom outer plate, and an isolated center plate. According to claim 1 or 9, the electric field simulation three-board line field intensity interference automatic test system for automotive electronic parts, wherein the device to be tested is arranged between the three boards of the three-board line fixture. According to claim 1, the electric field simulation three-plate line field intensity interference automatic test system of automotive electronic parts, wherein the three-plate line fixture uses the transmitting antenna to radiate disturbance energy to form a uniform electromagnetic field around the device under test,

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