Test apparatus and test method

Abstract

The application discloses a test device and a test method. The test device comprises a test cavity for placing a device to be tested, an antenna, a radio frequency module comprising at least two filters, a radio frequency switch and an analog-to-digital converter, the at least two filters being connected to the antenna, the sampling frequency bands of the at least two filters being different, the radio frequency switch being connected to the analog-to-digital converter and the at least two filters, and the radio frequency switch being used for switching the connection link of the analog-to-digital converter and each filter. In the test device, at least two filters with different sampling frequency bands are arranged, so that the wideband spectrum analysis can be met, a low-bandwidth analog-to-digital converter can be used for sampling, the import regulation can be avoided, and the cost can be reduced.

Description

Technical Field

[0001] This invention relates to the field of electronic equipment testing technology, and in particular to a testing device and a testing method. Background Technology

[0002] In EMC testing of related technologies, spurious signals radiated by the device under test (DUT) in various frequency bands are received by an antenna and fed into a spectrum analyzer. The spectrum analyzer then transmits the monitored spectrum and amplitude to a host computer to generate a test report. However, the spectrum analyzer used is an imported ultra-wideband receiver, which internally employs an ultra-wideband radio frequency sampling analog-to-digital converter (ADC), and ADCs are subject to import controls. Summary of the Invention

[0003] This invention provides a testing device and a testing method.

[0004] A testing device according to an embodiment of the present invention includes:

[0005] The test chamber is used to house the device under test.

[0006] antenna;

[0007] The radio frequency module includes at least two filters, a radio frequency switch, and an analog-to-digital converter. The at least two filters are connected to the antenna and have different sampling frequency bands. The radio frequency switch is connected to the analog-to-digital converter and the at least two filters and is used to switch the connection link between the analog-to-digital converter and each of the filters.

[0008] In the aforementioned testing equipment, by setting at least two filters with different sampling frequency bands, sampling can be achieved using a low-bandwidth analog-to-digital converter while satisfying broadband spectrum analysis requirements, thus avoiding import controls and reducing costs.

[0009] In some embodiments, the at least two filters include a first filter and a second filter, the sampling frequency band of the first filter is greater than that of the second filter, the RF switch includes a first RF switch, the RF module further includes a first mixer and a second mixer, the first mixer is connected to the first filter and the first RF switch, the second mixer is connected to the analog-to-digital converter, the second filter is connected to the first RF switch, and the first RF switch is used to switch the connection link between the second mixer and the first mixer and the second filter.

[0010] In some embodiments, the radio frequency module further includes a first amplifier and a second amplifier, the first amplifier being connected to the first mixer and the first filter, and the second amplifier being connected to the first radio frequency switch and the second filter.

[0011] In some embodiments, the at least two filters include a third filter whose sampling frequency band is less than that of the second filter. The RF module further includes a second RF switch connected to the second mixer and the analog-to-digital converter. The third filter is connected to the second RF switch, which is used to switch the connection link between the analog-to-digital converter and the third filter and the second mixer.

[0012] In some embodiments, the radio frequency module further includes a third amplifier connected to the third filter and the second radio frequency switch.

[0013] In some implementations, the amplifier is an adjustable amplifier.

[0014] In some embodiments, the test equipment includes a digital signal link unit connected to the analog-to-digital converter (ADC), which is used to perform spectrum analysis based on the digital signal output by the ADC.

[0015] In some embodiments, the radio frequency module further includes a control unit connected to the radio frequency switch and used to control the radio frequency switch to switch the connection link between the analog-to-digital converter and each of the filters.

[0016] In some embodiments, the test equipment includes an electrical chamber and a heat dissipation assembly located outside the test cavity. The heat dissipation assembly and the radio frequency module are located inside the electrical chamber. The heat dissipation assembly includes a fan and an air guide shroud. The air guide shroud covers the radio frequency module and has an air inlet and an air outlet. The air inlet is correspondingly arranged with the fan.

[0017] One embodiment of the present invention provides a testing method using the testing equipment described in any of the above embodiments. The testing method includes:

[0018] Place the device under test into the test chamber;

[0019] Turn on the device under test;

[0020] The radio frequency switch switches the connection link between the analog-to-digital converter and each of the filters until the frequency band sampling of all filters is completed;

[0021] The digital signal output from the analog-to-digital converter is processed to obtain the electromagnetic spectrum analysis of the electromagnetic waves radiated by the device under test.

[0022] In the above testing method, by setting at least two filters with different sampling frequency bands, sampling can be achieved using a low-bandwidth analog-to-digital converter while satisfying broadband spectrum analysis, thus avoiding import controls and reducing costs.

[0023] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 This is an exploded view of the testing equipment according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the test equipment according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the test method according to an embodiment of the present invention.

[0028] The realization of the objective, functional characteristics and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0029] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. They can refer to a mechanical connection or an electrical connection. They can refer to a direct connection or an indirect connection through an intermediate medium, and they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0034] Please refer to Figure 1 and Figure 2 A test device 100 according to an embodiment of the present invention includes a test cavity 12, an antenna 14, and a radio frequency module 16. The test cavity 12 is used to place the device under test (DUT). The antenna 14 can be used to receive electromagnetic waves radiated to the external interface by the DUT during operation. The radio frequency module 16 includes at least two filters, a radio frequency switch, and an analog-to-digital converter (ADC) 18. The at least two filters are connected to the antenna 14, and the at least two filters have different sampling frequency bands. The radio frequency switch is connected to the ADC 18 and the at least two filters, and the radio frequency switch is used to switch the connection link between the ADC 18 and each filter.

[0035] In the aforementioned test equipment 100, by setting at least two filters with different sampling frequency bands, sampling can be achieved using a low-bandwidth analog-to-digital converter 18 while satisfying broadband spectrum analysis, thus avoiding import controls and reducing costs.

[0036] Specifically, the aforementioned test equipment 100 can be an EMC (Electromagnetic Compatibility) test equipment, which can be used for EMI (Electromagnetic Interference) radiation testing in EMC testing. When the device under test (DUT) is operating, it can radiate electromagnetic waves (electromagnetic interference signals) to the outside world. By sampling the electromagnetic waves radiated by the DUT, the spectrum analysis of the DUT can be obtained.

[0037] Please combine Figure 1 The front side of the test chamber 12 is also provided with an opening 20 and a door 22. The door 22 is rotatably connected to the test chamber 12 and is used to close and open the opening 20. The test chamber 12 can be a metal chamber with an absorbing layer formed on its inner wall to reduce the adverse effects of electromagnetic waves reflected from the test chamber 12 on the test results. The door 22 can be an electromagnetically shielded door 22.

[0038] In this embodiment of the invention, the test chamber 12 can form a miniature anechoic chamber. The antenna 14 of the test device 100 is capable of receiving the electromagnetic waves radiated to the outside by the device under test (DUT) inside the test chamber 12 when it is working. After receiving the electromagnetic waves radiated by the DUT, the antenna 14 transmits them to the filter electrically connected to it.

[0039] The radio frequency module 16 may include a receiver, which includes at least two filters, an radio frequency switch, and an analog-to-digital converter 18. The number of filters can be determined based on the frequency band sampled by the device under test. No specific limitation is made here. In one example, the receiver may include three filters, each with a different sampling frequency band, enabling ultra-wideband spectrum analysis from DC to 18.5 GHz, with a maximum sampling rate of only 100 MHz.

[0040] The number of antennas 14 can be single or multiple. Antennas 14 can be arranged in the test cavity 12 to receive electromagnetic waves radiated by the device under test. Antennas 14 can be in the form of dipole antennas or slot antennas, etc. Antennas 14 can be mounted on the top wall of the test cavity 12 via a base.

[0041] The RF switch is used to switch the connection link between the analog-to-digital converter 18 and each filter. The RF switch can individually turn on the connection link between the analog-to-digital converter 18 and each filter, allowing the electromagnetic wave signal filtered by each filter to be transmitted to the analog-to-digital converter 18. The analog-to-digital converter 18 outputs a digital signal, and the receiver processes the digital signal output by the analog-to-digital converter 18 to obtain the electromagnetic wave spectrum analysis of the device under test.

[0042] The receiver can transmit the spectrum analysis results to a host computer (such as a personal computer) via wired or wireless means, and the host computer can then export a test report. The test equipment 100 may also include a display screen (not shown), which can display spectrum graphs for operator reference.

[0043] In one embodiment, the test equipment 100 can perform EMS (Electromagnetic Susceptibility) testing, and the radio frequency module 16 may further include a transmitter. The transmitter can emit electromagnetic waves into the test cavity 12 to simulate whether the device under test can operate normally in an electromagnetic interference environment.

[0044] In some embodiments, at least two filter packages are included: a first filter 24 and a second filter 36. The sampling frequency band of the first filter 24 is greater than that of the second filter 36. The radio frequency switch includes a first radio frequency switch 38. The radio frequency module 16 also includes a first mixer 40 and a second mixer 42. The first mixer 40 is connected to the first filter 24 and the first radio frequency switch 38. The second mixer 42 is connected to the analog-to-digital converter 18. The second filter 36 is connected to the first radio frequency switch 38. The first radio frequency switch 38 is used to switch the connection link between the second mixer 42 and the first mixer 40 and the second filter 36. In this way, the electromagnetic wave signal passing through the first filter 24 and the second filter 36 can be mixed to reduce the sampling frequency band.

[0045] Specifically, when the first RF switch 38 connects the second mixer 42 and the first mixer 40, the electromagnetic wave signal output by the first filter 24 can undergo two-stage mixing. In one embodiment, the first filter 24 can be a high-frequency filter. In one example, the sampling frequency band of the high-frequency filter is the 1GHz to 2GHz band.

[0046] With the first RF switch 38 activating the connection between the second mixer 42 and the second filter 36, the electromagnetic wave signal output from the second filter 36 can undergo a single-stage mixing. In one embodiment, the second filter 36 can be an intermediate frequency (IF) filter. In one example, the sampling frequency band of the IF filter is the 100MHz to 1GHz band.

[0047] The output from the filter to the mixer is an RF signal. In the mixer, the local oscillator signal is processed with the RF signal (e.g., by subtraction) to obtain the intermediate frequency (IF) signal. The local oscillator signal can be provided by the phase-locked loop of the RF module 16. In one example, a two-stage mixer can reduce the frequency of the electromagnetic signal output from the first filter 24 to 100MHz, and a single-stage mixer can reduce the frequency of the electromagnetic signal output from the second filter 36 to 100MHz. Therefore, the analog-to-digital converter 18 can be a low-bandwidth analog-to-digital converter.

[0048] In some embodiments, the RF module 16 further includes a first amplifier 44 and a second amplifier 46. The first amplifier 44 is connected to the first mixer 40 and the first filter 24, and the second amplifier 46 is connected to the first RF switch 38 and the second filter 36. This amplifies the RF signal to improve test accuracy.

[0049] Specifically, the input terminal of the first amplifier 44 is connected to the output terminal of the first filter 24. The first amplifier 44 can amplify the radio frequency signal output by the first filter 24, which can reduce test errors and improve test accuracy in subsequent processing.

[0050] The input terminal of the second amplifier 46 is connected to the output terminal of the second filter 36. The second amplifier 46 can amplify the radio frequency signal output by the second filter 36, which can reduce test errors and improve test accuracy in subsequent processing.

[0051] In some embodiments, at least two filters include a third filter 48, whose sampling frequency band is less than that of the second filter 36. The RF module 16 also includes a second RF switch 50, which is connected to the second mixer 42 and the analog-to-digital converter 18. The third filter 48 is connected to the second RF switch 50, which is used to switch the connection link between the analog-to-digital converter 18, the third filter 48, and the second mixer 42. In this way, the electromagnetic wave output by the third filter 48 can be directly sampled.

[0052] Specifically, in one implementation, the third filter 48 may be a low-frequency filter. In one example, the frequency band starting from the lowest segment, DC to 100MHz, enters the low-frequency filter for direct sampling.

[0053] In some embodiments, the RF module 16 further includes a third amplifier 52, which is connected to a third filter 48 and a second RF switch 50. This amplifies the RF signal to improve test accuracy.

[0054] Specifically, the input terminal of the third amplifier 52 is connected to the output terminal of the third filter 48. The third amplifier 52 can amplify the radio frequency signal output by the third filter 48, which can reduce test errors and improve test accuracy in subsequent processing.

[0055] In some implementations, please refer to Figure 2 The amplifier is an adjustable amplifier. This allows for adjustment of the amplifier's gain to flexibly adapt to different application scenarios.

[0056] Specifically, the first amplifier 44, the second amplifier 46, and the third amplifier 52 can all be adjustable amplifiers. The gain of the adjustable amplifiers can be adjusted to adapt to various changes in the radio frequency signal, ensuring that the amplified radio frequency signal meets the requirements. It is understood that in other embodiments, the first amplifier 44, the second amplifier 46, and the third amplifier 52 can also be other types of amplifiers.

[0057] In some embodiments, the test device 100 includes a digital signal link unit 54 connected to an analog-to-digital converter 18. The digital signal link unit 54 is used to perform spectrum analysis based on the digital signal output by the analog-to-digital converter 18. Thus, the digital signal output by the analog-to-digital converter 18 can be processed to obtain a spectrum analysis of the electromagnetic waves radiated by the device under test.

[0058] Specifically, the digital signal link unit 54 can process the digital signal output by the analog-to-digital converter 18 to obtain a spectrum analysis corresponding to the digital signal. The spectrum analysis yields a spectrum graph, thus enabling the visualization of the digital signal. That is, through human visual perception, one can intuitively identify the frequency band, amplitude, and other information of electromagnetic waves, or perform relevant numerical comparisons to determine whether the device under test meets safety requirements. Specifically, the digital signal link unit 54 can perform Fourier transform processing on the digital signal output by the analog-to-digital converter 18 and obtain the corresponding spectrum graph.

[0059] In one embodiment, the test device 100 may further include a display screen that can display a spectrum graph. The spectrum graph can also be sent to a host computer for display, and the host computer can export the test results.

[0060] In some embodiments, the RF module 16 further includes a control unit 56, which is connected to the RF switch and used to control the RF switch to switch the connection link between the analog-to-digital converter 18 and each filter. This enables automatic switching of the RF switch.

[0061] Specifically, the control unit 56 can control the RF switches according to a certain timing sequence to enable which filter to conduct with the analog-to-digital converter 18.

[0062] In one embodiment, the control unit 56 may include an MCU, which can control the switching state of the first RF switch 38 and the second RF switch 50 to complete the sampling of the electromagnetic wave frequency bands of all filter outputs by the analog-to-digital converter 18.

[0063] In some embodiments, the test equipment 100 includes an electrical chamber 58 located outside the test cavity 12 and a heat dissipation assembly. The heat dissipation assembly and the radio frequency module 16 are located inside the electrical chamber 58. The heat dissipation assembly includes a fan 60 and an air guide shroud 62. The air guide shroud 62 covers the radio frequency module 16 and has an air inlet and an air outlet, with the air inlet corresponding to the fan 60. In this way, the radio frequency module 16 can be cooled, ensuring that the radio frequency module 16 operates within its normal temperature range.

[0064] Specifically, when the fan 60 is working, it draws in cold air from the outside. The cold air is blown into the air guide shroud 62 through the air inlet, flows through the radio frequency module 16, absorbs heat to form hot air, and finally flows out of the air guide shroud 62 through the air outlet. Furthermore, the wall of the electrical room 58 may be provided with through holes, through which hot air is blown to the outside of the electrical room 58.

[0065] In some embodiments, the test equipment 100 also includes a control panel 64. The control panel 64 can be installed in front of the electrical room 58. The control panel 64 may be equipped with a display screen, operation buttons, etc. The display screen can display the corresponding operation interface, and the display screen may also be a touch screen, through which the operating status of the test equipment 100 can be set and controlled.

[0066] The test equipment 100 also includes a power supply module 66 disposed above the air guide shroud 62. The power supply module 66 can supply power to electrical components, which may include an RF module 16, a fan 60, a control panel 64, etc. The power supply module 66 can also supply power to the device under test (DUT) inside the test chamber 12. In one embodiment, the power supply module 66 can convert AC power to DC power. The power supply module 66 disposed above the air guide shroud 62 can also be cooled.

[0067] Please refer to Figure 3 One embodiment of the present invention provides a testing method using the testing equipment 100 described in any of the above embodiments. The testing method includes:

[0068] Step 11: Place the device under test into the test chamber 12;

[0069] Step 13, turn on the device under test;

[0070] Step 15: Switch the connection link between the RF switch and each filter until the frequency band sampling of all filters is completed;

[0071] Step 17: Process the digital signal output by the analog-to-digital converter to obtain the electromagnetic spectrum analysis of the device under test.

[0072] In the above testing method, by setting at least two filters with different sampling frequency bands, sampling can be achieved using a low-bandwidth analog-to-digital converter 18 while satisfying broadband spectrum analysis, thus avoiding import controls and reducing costs.

[0073] Specifically, door 22 can be opened to place the device under test (DUT) into test chamber 12. The DUT can be connected to a power plug, which is powered by power supply module 66. After the DUT is powered on, it can be turned on to start operating. Then door 22 can be closed.

[0074] The antenna 14 receives the electromagnetic wave signal radiated by the device under test when it is working, and finally the digital signal sampled by the digital signal link unit 54 processes the digital signal to obtain the corresponding spectrum graph.

[0075] Since the radio frequency module 16 of this embodiment includes at least two filters, each of which can sample different frequency bands, it can meet the requirements of ultra-wideband spectrum analysis (such as 18.5G ultra-wideband spectrum analysis) even when using a low-bandwidth analog-to-digital converter 18.

[0076] It should be noted that the above explanation of the implementation method and beneficial effects of the testing equipment 100 also applies to the testing method of this implementation method. To avoid redundancy, it will not be elaborated in detail here.

[0077] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0078] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A testing device, characterized in that, include: The test chamber is used to house the device under test. antenna; The radio frequency module includes at least two filters, a radio frequency switch, and an analog-to-digital converter. The at least two filters are connected to the antenna and have different sampling frequency bands. The radio frequency switch is connected to the analog-to-digital converter and the at least two filters and is used to switch the connection link between the analog-to-digital converter and each of the filters. The at least two filters include a first filter and a second filter, the sampling frequency band of the first filter is greater than the sampling frequency band of the second filter, the RF switch includes a first RF switch, the RF module further includes a first mixer and a second mixer, the first mixer is connected to the first filter and the first RF switch, the second mixer is connected to the analog-to-digital converter, the second filter is connected to the first RF switch, and the first RF switch is used to switch the connection link between the second mixer and the first mixer and the second filter; The at least two filters include a third filter, the sampling frequency band of the third filter being less than that of the second filter, the radio frequency module further includes a second radio frequency switch, the second radio frequency switch being connected to the second mixer and the analog-to-digital converter, the third filter being connected to the second radio frequency switch, and the second radio frequency switch being used to switch the connection link between the analog-to-digital converter and the third filter and the second mixer; The analog-to-digital converter (ADC) is a low-bandwidth ADC, and only one ADC is provided.

2. The testing equipment according to claim 1, characterized in that, The radio frequency module further includes a first amplifier and a second amplifier, wherein the first amplifier is connected to the first mixer and the first filter, and the second amplifier is connected to the first radio frequency switch and the second filter.

3. The testing equipment according to claim 1, characterized in that, The radio frequency module also includes a third amplifier, which is connected to the third filter and the second radio frequency switch.

4. The testing equipment according to claim 2 or 3, characterized in that, The amplifier is an adjustable amplifier.

5. The testing equipment according to claim 1, characterized in that, The test equipment includes a digital signal link unit connected to the analog-to-digital converter (ADC), and the digital signal link unit is used to perform spectrum analysis based on the digital signal output by the ADC.

6. The testing equipment according to claim 1, characterized in that, The radio frequency module also includes a control unit, which is connected to the radio frequency switch and is used to control the radio frequency switch to switch the connection link between the analog-to-digital converter and each of the filters.

7. The testing equipment according to claim 1, characterized in that, The test equipment includes an electrical chamber and a heat dissipation assembly located outside the test cavity. The heat dissipation assembly and the radio frequency module are located inside the electrical chamber. The heat dissipation assembly includes a fan and an air guide shroud. The air guide shroud covers the radio frequency module and has an air inlet and an air outlet. The air inlet is correspondingly arranged with the fan.

8. A testing method, characterized in that, Using the testing equipment according to any one of claims 1-7, the testing method includes: Place the device under test into the test chamber; Turn on the device under test; The radio frequency switch switches the connection link between the analog-to-digital converter and each of the filters until the frequency band sampling of all filters is completed; The digital signal output from the analog-to-digital converter is processed to obtain the electromagnetic spectrum analysis of the electromagnetic waves radiated by the device under test.

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