Test system

Abstract

The utility model provides a test system which is used for testing the electromagnetic interference capability of electronic equipment of a vehicle, the test system comprises a signal generator, a power amplifier, an attenuator and an injection probe, and the signal generator is used for generating a detection signal; the power amplifier is connected with the signal generator and is used for amplifying and adjusting the power of the detection signal; the attenuator is connected with the power amplifier, is provided with multiple stages of attenuation ratios, and is used for selectively carrying out attenuation adjustment on the detection signal amplified and adjusted by the power amplifier according to the corresponding attenuation ratio; the injection probe is connected with the attenuator and is used for being coupled with a test wire harness of electronic equipment and converting a detection signal which is attenuated and adjusted by the attenuator into an electromagnetic signal. Through the mode, the test cost of the electromagnetic compatibility test can be effectively reduced, and the test efficiency of the electromagnetic compatibility test can be effectively improved.

Description

Technical Field

[0001] This application relates to the technical field of electromagnetic compatibility testing for vehicle parts, and particularly to a testing system. Background Art

[0002] With the development of automotive (vehicle) technology, more and more electronic products are adopted, making the electromagnetic environment in which the vehicle is located increasingly complex. The complex spatial electromagnetic field is likely to be coupled into the circuit where the electronic product is located through the wiring harness connecting the electronic products, affecting the normal operation of the electronic products. BCI (Bulk Current Injection) testing is a common electromagnetic compatibility testing for automotive parts, used to detect the anti-interference ability of automotive parts. The testing method is to clamp the wiring harness of the device under test (DUT) with an injection probe, and inject interference into the measured wiring harness of the DUT through the injection probe. OEMs in the market have specified the test levels and test frequencies for BCI testing in their respective product standards. However, due to different design considerations and combined with their own product positioning, the test levels and test frequency ranges specified by each OEM are different. During the testing process, within the same test frequency band, electronic products often need to undergo electromagnetic compatibility testing at multiple test levels. In other words, within the same test frequency band, the testing system needs to output detection signals with different powers to conduct electromagnetic compatibility testing on electronic devices. In the existing testing system, the power adjustment gears of the power amplifier for the detection signal are limited. Within the same test frequency band, a single power amplifier often cannot meet the testing requirements, thus requiring frequent replacement of the power amplifier, which greatly affects the testing efficiency and testing cost. Summary of the Utility Model

[0003] This application provides a testing system for testing the electromagnetic interference ability of electronic devices of a vehicle. The testing system includes: a signal generator, a power amplifier, an attenuator, and an injection probe. The signal generator is used to generate a detection signal; the power amplifier is connected to the signal generator and is used to amplify and adjust the power of the detection signal; the attenuator is connected to the power amplifier, and the attenuator is provided with multiple attenuation ratios for selectively attenuating and adjusting the detection signal amplified and adjusted by the power amplifier with the corresponding attenuation ratio; the injection probe is connected to the attenuator and is used to couple with the test wiring harness of the electronic device and convert the detection signal attenuated and adjusted by the attenuator into an electromagnetic signal.

[0004] In some embodiments, the attenuator is integrally provided on the power amplifier.

[0005] In some embodiments, the signal generator, the power amplifier, the attenuator, and the injection probe are all disposed in a shielding area for placing the electronic device to be tested. The test system further includes a controller disposed outside the shielding area. The controller is respectively connected to the signal generator and the power amplifier. The controller is configured to control the signal generator to generate a detection signal outside the shielding area, and to control the power amplifier to amplify and adjust the power of the detection signal outside the shielding area.

[0006] In some embodiments, the controller is further connected to the attenuator and is configured to selectively control the attenuator to switch the attenuation ratio.

[0007] In some embodiments, the controller includes a processing circuit, the attenuator includes an attenuation circuit and an adjustment circuit. The attenuation circuit is connected to the adjustment circuit, and the adjustment circuit is connected to the processing circuit. Wherein, the adjustment circuit adjusts the attenuation ratio of the attenuation circuit based on the control signal of the processing circuit, so that the attenuation circuit attenuates the detection signal that has been amplified and adjusted with the corresponding attenuation ratio.

[0008] In some embodiments, the test system includes multiple groups of communication cables. The signal generator, the power amplifier, and the attenuator are respectively connected to the controller through corresponding communication cables.

[0009] In some embodiments, the communication cable includes a USB cable, a network cable, or an optical fiber.

[0010] In some embodiments, the test system includes: a first power probe, which is respectively connected to the power amplifier and the controller, and is configured to collect the forward power data of the power amplifier and transmit it to the controller; a second power probe, which is respectively connected to the power amplifier and the controller, and is configured to collect the reverse power data of the power amplifier and transmit it to the controller.

[0011] In some embodiments, the signal generator includes a radio frequency circuit, the power amplifier includes a power amplification circuit, the attenuator includes an attenuation circuit and an adjustment circuit for adjusting the attenuation ratio of the attenuation circuit, and the controller includes a processing circuit; the control end of the radio frequency circuit is connected to the first signal end of the processing circuit, the output end of the radio frequency circuit is connected to the input end of the power amplification circuit, the control end of the power amplification circuit is connected to the second signal end of the processing circuit, the output end of the power amplification circuit is connected to the input end of the attenuation circuit, the output end of the attenuation circuit is connected to the injection probe, and the control end of the attenuation circuit is connected to the third signal end of the processing circuit.

[0012] In some embodiments, the attenuator is provided with a shielding member for shielding electromagnetic signals.

[0013] The beneficial effects of the embodiments of the present application are as follows: The present application provides a test system for testing the electromagnetic interference ability of electronic devices of a vehicle. The test system includes a signal generator, a power amplifier, an attenuator, and an injection probe. Among them, an attenuator is arranged between the power amplifier and the injection probe, so that the test level of the test system, that is, the test power, is jointly determined by the power amplifier and the attenuator, and the attenuator is provided with multiple attenuation ratios. In this way, when the power adjustment gear of the power amplifier for the detection signal (that is, the amplification adjustment gear of the power amplifier for the detection signal) cannot meet the test level requirements of the electromagnetic compatibility test, the test system can further attenuate and adjust the detection signal by adjusting the attenuation ratio of the attenuator, so that the power of the detection signal meets the test level requirements of the electromagnetic compatibility test, without replacing the power amplifier and the attenuator, thereby avoiding the loss of test cost and test time caused by replacing the power amplifier and the attenuator, and effectively reducing the test cost of the electromagnetic compatibility test and effectively improving the test efficiency of the electromagnetic compatibility test. Moreover, during the test process, frequently replacing the power amplifier and the attenuator will also increase the damage probability of the power amplifier and the attenuator. Therefore, an attenuator with an adjustable attenuation ratio is arranged between the power amplifier and the injection probe, and there is no need to frequently replace the power amplifier and the attenuator, thereby effectively reducing the damage probability of components such as the power amplifier and the attenuator, and effectively ensuring the accuracy of the electromagnetic compatibility test of the test system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a schematic structural diagram of an embodiment of the test system of the present application;

[0015] Figure 2 is Figure 1 a schematic connection diagram of the circuit structure in the test system shown in DETAILED DESCRIPTION OF THE EMBODIMENTS

[0016] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0017] The terms "first" and "second" in this application are only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. In the description of this application, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0018] As Figure 1 shown, this application provides a test system 10 for testing the electromagnetic interference ability of an electronic device 20 of a vehicle. Specifically, the test system 10 in the embodiments of this application can perform electromagnetic compatibility testing on the electronic device 20 of the vehicle by the bulk current injection method (BCI). Among them, the test system 10 includes a signal generator 100, a power amplifier 200, an attenuator 300, and an injection probe 400.

[0019] The signal generator 100 is used to generate a detection signal. The power amplifier 200 is connected to the signal generator 100 and is used to receive the detection signal and amplify and adjust the detection signal. The attenuator 300 is connected to the power amplifier 200. The attenuator 300 is provided with multiple attenuation ratios, such as 0 dB (that is, the attenuator 300 has no attenuation effect or a very small attenuation effect on the detection signal), 3 dB, and 6 dB, etc., and is used to selectively attenuate and adjust the detection signal amplified and adjusted by the power amplifier 200 with the corresponding attenuation ratio. The injection probe 400 is connected to the attenuator 300 and is used to couple with the test harness of the electronic device 20 to be tested (also known as the device under test) and convert the detection signal attenuated and adjusted by the attenuator 300 into an electromagnetic signal to perform electromagnetic compatibility testing on the electronic device 20.

[0020] It should be noted that in the embodiments of this application, the decibel (dB) is used as the unit of the attenuation ratio to represent the magnitude of the attenuation ratio. The specific definition of the decibel can be referred to in the prior art and will not be elaborated in detail here.

[0021] Specifically, during the testing process, within the same test frequency band, electronic products often need to undergo electromagnetic compatibility tests at multiple test levels. In other words, within the same test frequency band, the test system 10 needs to output detection signals with different powers to conduct electromagnetic compatibility tests on the electronic device 20. Usually, however, the power adjustment gears of the power amplifier 200 for the detection signals are limited. Within the same test frequency band, a single power amplifier 200 often cannot meet the test requirements, thus requiring frequent replacement of the power amplifier 200. This greatly affects the test efficiency and cost. Moreover, frequently switching components in the test system 10 will also increase the damage probability of components such as the power amplifier 200, thereby affecting the accuracy of the electromagnetic compatibility test of the test system 10 on the electronic device 20. In the embodiment of the present application, an attenuator 300 is provided between the power amplifier 200 and the injection probe 400, so that the test level of the test system 10, that is, the test power, is jointly determined by the power amplifier 200 and the attenuator 300. And the attenuator 300 is provided with multiple attenuation ratios. Thus, when the power adjustment gear of the power amplifier 200 for the detection signal (that is, the amplification adjustment gear of the power amplifier 200 for the detection signal) cannot meet the test level requirements of the electromagnetic compatibility test, the test system 10 can further adjust the attenuation ratio of the attenuator 300 to attenuate the detection signal, so that the power of the detection signal meets the test level requirements of the electromagnetic compatibility test, without the need to disassemble and replace the power amplifier 200 and the attenuator 300, thereby avoiding the loss of test cost and test time caused by disassembling and replacing the power amplifier 200 and the attenuator 300, and effectively reducing the test cost of the electromagnetic compatibility test and effectively improving the test efficiency of the electromagnetic compatibility test. And during the testing process, frequently disassembling and replacing the power amplifier 200 and the attenuator 300 will also increase the damage probability of the power amplifier 200 and the attenuator 300. Therefore, by providing an attenuator 300 with an adjustable attenuation ratio between the power amplifier 200 and the injection probe 400, there is no need to frequently disassemble and replace the power amplifier 200 and the attenuator 300, thereby effectively reducing the damage probability of components such as the power amplifier 200 and the attenuator 300, and effectively ensuring the accuracy of the electromagnetic compatibility test of the test system 10.

[0022] For example, Figure 1As shown, in an electromagnetic compatibility test embodiment, the device under test is a rear car taillight provided by a manufacturer. The device under test and the auxiliary device 30 are placed on a low dielectric constant material with a thickness of 5 cm. The auxiliary device 30 includes a storage battery and a control element. The low dielectric constant material is placed on a wooden table covered with a copper plate. The test is conducted according to the test method of GB / T 33014.4-2016. During the test, the entire test frequency range is divided into two test frequency bands, namely the first frequency band and the second frequency band. Among them, in the first frequency band, there are tests with a relatively low test level, and the lowest power adjustment gear of the power amplifier 200 cannot meet the requirements. Therefore, an attenuator 300 is needed to further adjust the detection signal. In the second frequency band, there are tests with a relatively high test level, and the highest power adjustment gear of the power amplifier 200 can meet the test level requirements, so there is no need for the attenuator 300 to perform additional adjustment on the detection signal. Specifically as follows:

[0023] In the first frequency band, the test software (the test software set in the controller 500, specifically refer to the content described below) communicates with the attenuator 300 to control the attenuator 300 to turn on a 6 dB attenuation. The signal generator 100 outputs a detection signal to the power amplifier 200. The power amplifier 200 amplifies the detection signal and transmits it to the attenuator 300. The detection signal undergoes a 6 dB attenuation by the attenuator 300. Finally, the detection signal is output through a radio frequency cable to the injection probe 400, and then is injected into the test harness of the device under test in the form of electromagnetic radiation through the injection probe 400. Subsequently, the test proceeds to the second frequency band. The test software communicates with the attenuator 300 to control the attenuator 300 to turn on a 0 dB attenuation, that is, to make the attenuator 300 not perform attenuation adjustment on the detection signal. Finally, the detection signal is output through a radio frequency cable to the injection probe 400, and then is injected into the test harness of the device under test in the form of electromagnetic radiation through the injection probe 400.

[0024] Optionally, in some embodiments, the attenuator 300 is integrally provided on the power amplifier 200, so that the integration degree of the attenuator 300 and the power amplifier 200 can be effectively improved.

[0025] Optionally, in some embodiments, the attenuator 300 is provided with a shielding member for shielding electromagnetic signals. For example, the detection signals flowing through the power amplifier 200 or injected into the probe 400 will radiate electromagnetic signals to the surrounding area in the form of electromagnetic radiation. The electromagnetic signals will affect the internal circuits of the attenuator 300, such as the attenuation circuit 320, the adjustment circuit 310, etc., which are used to attenuate and adjust the detection signals, thereby affecting the adjustment accuracy of the attenuator 300, and further affecting the accuracy of electromagnetic compatibility testing. Therefore, by providing a shielding member on the attenuator 300, the electromagnetic radiation impact of the power amplifier 200 and / or the injection probe 400 on the attenuator 300 can be effectively reduced, thereby effectively improving the working stability of the attenuator 300 and further effectively improving the accuracy of electromagnetic compatibility testing.

[0026] Optionally, as Figure 1 shown, in some embodiments, the signal generator 100, the power amplifier 200, the attenuator 300, and the injection probe 400 are all disposed in a shielding area 800 for placing the electronic device 20 to be tested. Specifically, the signal generator 100, the power amplifier 200, the attenuator 300, and the injection probe 400 are components for transmitting and conveying detection signals. Placing them in the shielding area 800 can effectively reduce the probability of the detection signals being interfered, thereby effectively improving the accuracy of the electromagnetic compatibility testing of the test system 10. Moreover, by isolating the signal generator 100, the power amplifier 200, the attenuator 300, and the injection probe 400, which are radioactive during operation, through the shielding area 800, the safety of the test personnel can be effectively protected.

[0027] In addition, the test system 10 further includes a controller 500, which is disposed outside the shielding area 800. The controller 500 is respectively connected to the signal generator 100 and the power amplifier 200. The controller 500 is used to control the signal generator 100 to generate detection signals outside the shielding area 800, and to control the power amplifier 200 to amplify and adjust the power of the detection signals outside the shielding area 800. Specifically, the signal generator 100 and the power amplifier 200 are respectively remotely controlled by the controller 500 disposed outside the shielding area 800. Thus, after the signal generator 100, the power amplifier 200, the attenuator 300, and the injection probe 400 are correspondingly connected, and the controller 500 is correspondingly connected to the signal generator 100 and the power amplifier 200, the test personnel can remotely control the signal generator 100 and the power amplifier 200 to work outside the shielding area 800, so that there is no need to enter and exit the shielding area 800, effectively improving the safety of electromagnetic compatibility testing.

[0028] Optionally, in some embodiments, the controller 500 is further connected to the attenuator 300 for selectively controlling the attenuator 300 to switch the attenuation ratio. Specifically, the attenuator 300 is controlled by the controller 500 disposed outside the shielding area 800. The controller 500 can control the attenuator 300 to switch the attenuation ratio. Thus, when it is necessary to frequently switch the test level within a test frequency band, the controller 500 automatically controls or under the manual control of the tester on the controller 500, controls the attenuator 300 to switch the attenuation ratio to switch the test level, without the tester frequently entering and leaving the shielding area 800 to switch the attenuation ratio of the attenuator 300, thereby effectively improving the safety and test efficiency of electromagnetic compatibility testing.

[0029] Optionally, as Figure 2 shown, in some embodiments, the controller 500 includes a processing circuit 510, the attenuator 300 includes an attenuation circuit 320 and an adjustment circuit 310. The attenuation circuit 320 is connected to the adjustment circuit 310, and the adjustment circuit 310 is connected to the processing circuit 510. Among them, the adjustment circuit 310 adjusts the attenuation ratio of the attenuation circuit 320 based on the control signal of the processing circuit 510, so that the attenuation circuit 320 attenuates and adjusts the detected signal that has been amplified and adjusted with the corresponding attenuation ratio.

[0030] Specifically, as Figure 2 shown, the signal generator 100 includes a radio frequency circuit 110, the power amplifier 200 includes a power amplification circuit 210, the attenuator 300 includes an attenuation circuit 320 and an adjustment circuit 310 for adjusting the attenuation ratio of the attenuation circuit 320, and the controller 500 includes a processing circuit 510; the control end of the radio frequency circuit 110 is connected to the first signal end of the processing circuit 510, the output end of the radio frequency circuit 110 is connected to the input end of the power amplification circuit 210, the control end of the power amplification circuit 210 is connected to the second signal end of the processing circuit 510, the output end of the power amplification circuit 210 is connected to the input end of the attenuation circuit 320, and the output end of the attenuation circuit 320 is connected to the injection probe 400. The control end of the attenuation circuit 320 is connected to the third signal end of the processing circuit 510. Among them, the processing circuit 510 is provided with test software, and the processing circuit 510 runs the test software. The tester can manually control the test software or the test software automatically runs according to the existing parameters, so that the processing circuit 510 adjusts the parameters of electromagnetic compatibility testing, such as the frequency of the detected signal output by the radio frequency circuit, and the adjustment gear of the power amplification circuit 210 for the detected signal, and the attenuation ratio of the attenuator 300, etc. Optionally, the controller 500 can be an electronic device 20 such as a computer with certain processing capabilities.

[0031] Optionally, in some embodiments, the test system 10 further includes a first power probe 600 and a second power probe 700. The first power probe 600 is respectively connected to the power amplifier 200 and the controller 500, and is configured to collect forward power data of the power amplifier 200 and transmit it to the controller 500. The second power probe 700 is respectively connected to the power amplifier 200 and the controller 500, and is configured to collect reverse power data of the power amplifier 200 and transmit it to the controller 500. Wherein, the controller 500 can perform feedback adjustment on the power amplifier 200 and the attenuator 300 according to the forward power data and / or the reverse power data, so that the detection signal meets the test level requirements of electromagnetic compatibility testing.

[0032] Optionally, in some embodiments, the test system 10 includes multiple groups of communication cables. For example, in the embodiments of the present application, the communication cables can be communication cables such as USB cables, network cables, or optical fibers. The signal generator 100, the power amplifier 200, and the attenuator 300 are respectively connected to the controller 500 through corresponding communication cables, so as to effectively improve the signal transmission stability of the controller 500 to the signal generator 100, the power amplifier 200, and the attenuator 300, so that the controller 500 can stably control the signal generator 100, the power amplifier 200, and the attenuator 300 to work, and further effectively improve the working stability of the test system 10.

[0033] Specifically, the signal generator 100, the power amplification circuit 210, and the attenuator 300 are all functional devices provided with corresponding circuits. For example, for the signal generator 100, it includes a housing, a corresponding circuit structure for forming the radio frequency circuit 110, and multiple signal plug-in ports for plugging communication cables. Among them, the signal terminals of the radio frequency circuit 110, such as the control terminal and the output terminal, are respectively connected to the corresponding signal plug-in ports. Another example is the power amplifier 200, which includes a housing, a corresponding circuit structure for forming the power amplification circuit 210, and multiple signal plug-in ports for plugging communication cables. Among them, the signal terminals of the power amplification circuit 210, such as the control terminal, the output terminal, and the input terminal, are respectively connected to the corresponding signal plug-in ports. Another example is the attenuator 300, which includes a housing, a corresponding circuit structure for forming the adjustment circuit 310 and the attenuation circuit 320, and multiple signal plug-in ports for plugging communication cables. Among them, the signal terminals of the attenuation circuit 320 and the signal terminals of the adjustment circuit 310, such as the control terminal, the output terminal, and the input terminal, are respectively connected to the corresponding signal plug-in ports. Based on this, the signal generator 100, the power amplifier 200, and the attenuator 300 can be communicatively connected in a plug-in manner through corresponding communication cables.

[0034] Optionally, in some embodiments, the first power probe 600 is connected to the controller 500 and the power amplifier 200 respectively through corresponding communication cables, and the second power probe 700 is connected to the controller 500 and the power amplifier 200 respectively through corresponding communication cables.

[0035] It should be noted that in the accompanying drawings herein, they are only for showing the structural relationship and connection relationship of the products of the present application for utility model, and do not thereby limit the specific structural dimensions of the products of the present application for utility model.

[0036] The above are only the implementation manners of the present utility model, and do not thereby limit the patent scope of the present utility model. Any equivalent structural or equivalent process transformation made by using the content of the specification and drawings of the present utility model, or directly or indirectly applied to other related technical fields, shall equally be included in the patent protection scope of the present utility model.

Claims

1. A testing system, characterized in that: Used to test the electromagnetic interference capability of electronic equipment of a vehicle, the test system comprises: A signal generator, used for generating a detection signal; A power amplifier, connected to the signal generator, for amplifying and adjusting the power of the detection signal; an attenuator connected to the power amplifier, wherein the attenuator is provided with multiple attenuation ratios and is used to selectively attenuate and adjust the detection signal amplified and adjusted by the power amplifier at corresponding attenuation ratios; The injection probe is connected to the attenuator, and is used to couple with the test harness of the electronic device and convert the detection signal attenuated by the attenuator into an electromagnetic signal.

2. The test system according to claim 1, characterized in that: The attenuator is integrated on the power amplifier.

3. The test system according to claim 1, characterized in that: The signal generator, the power amplifier, the attenuator and the injection probe are all arranged in a shielded area for placing the electronic equipment to be tested. The test system also includes a controller, which is arranged outside the shielded area. The controller is connected to the signal generator and the power amplifier respectively. The controller is used to control the signal generator to generate the detection signal outside the shielded area, and is used to control the power amplifier to amplify and adjust the power of the detection signal outside the shielded area.

4. The test system according to claim 3, characterized in that: The controller is also connected to the attenuator for selectively controlling the attenuator to switch the attenuation ratio.

5. The test system according to claim 4, characterized in that: The controller includes a processing circuit, and the attenuator includes an attenuation circuit and an adjustment circuit. The attenuation circuit is connected to the adjustment circuit, and the adjustment circuit is connected to the processing circuit, wherein the adjustment circuit adjusts the attenuation ratio of the attenuation circuit based on a control signal of the processing circuit so that the attenuation circuit attenuates the detection signal that has been amplified and adjusted with a corresponding attenuation ratio.

6. The test system according to claim 3, characterized in that: The test system includes a plurality of groups of communication cables, and the signal generator, the power amplifier and the attenuator are respectively connected to the controller through the corresponding communication cables.

7. The test system according to claim 6, characterized in that: The communication cable includes a USB cable, a network cable, or an optical fiber.

8. The test system according to claim 3, characterized in that: The test system comprises: A first power sensor is connected to the power amplifier and the controller respectively, and is used to collect forward power data of the power amplifier and transmit it to the controller; The second power probe is connected to the power amplifier and the controller respectively, and is used for collecting reverse power data of the power amplifier and transmitting the reverse power data to the controller.

9. The test system according to claim 3, characterized in that: The signal generator includes a radio frequency circuit, the power amplifier includes a power amplification circuit, the attenuator includes an attenuation circuit and an adjustment circuit for adjusting the attenuation ratio of the attenuation circuit, and the controller includes a processing circuit; The control end of the RF circuit is connected to the first signal end of the processing circuit, the output end of the RF circuit is connected to the input end of the power amplifier circuit, the control end of the power amplifier circuit is connected to the second signal end of the processing circuit, the output end of the power amplifier circuit is connected to the input end of the attenuation circuit, the output end of the attenuation circuit is connected to the injection probe, and the control end of the attenuation circuit is connected to the third signal end of the processing circuit.

10. The test system according to claim 1, characterized in that: The attenuator is provided with a shielding member, and the shielding member is used for shielding electromagnetic signals.

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