Wave absorbing structure and test darkroom for antenna test and electromagnetic compatibility test

Abstract

The invention provides a wave-absorbing structure for antenna testing and electromagnetic compatibility testing, and the structure comprises a top wave-absorbing structure which is laid on the top surface of a testing darkroom; the bottom wave-absorbing structure is laid on the bottom surface of the test darkroom; and the four side wave absorbing structures are respectively laid on four side surfaces of the testing darkroom and are sequentially a first wave absorbing structure, a second wave absorbing structure, a third wave absorbing structure and a fourth wave absorbing structure in the clockwise direction. According to the wave-absorbing structure, different types of wave-absorbing material combinations are adopted, so that a multifunctional testing system compatible with antenna testing and electromagnetic compatibility testing is formed in the same testing darkroom space.

Description

Technical Field

[0001] This application relates to the field of electronic testing technology, and more specifically, to an absorbing structure and a test anechoic chamber for antenna testing and electromagnetic compatibility testing. Background Technology

[0002] Electromagnetic compatibility (EMC) testing is an essential part of the research, development, production, and acceptance testing of electronic equipment. It assesses the equipment's ability to emit electromagnetic interference (EMI) and resist external EMI in an electromagnetic environment. According to application standards, EMC testing is generally divided into two main categories: civilian standard testing and military standard testing. These two categories differ significantly in terms of test frequency bands, absorption performance, and power tolerance requirements. To ensure testing accuracy, it is usually necessary to conduct the tests in an environment with good electromagnetic shielding and absorption performance; this environment is called a test anechoic chamber. A test anechoic chamber establishes an ideal testing environment by arranging absorbing materials on the inner wall of the shielding structure to form a specific absorbing structure. However, existing test anechoic chambers generally suffer from limited functionality. In practical engineering, it is often necessary to construct multiple anechoic chambers or frequently change the absorbing structure, resulting in high testing costs and long testing cycles. Summary of the Invention

[0003] This application provides an absorbing structure and an anechoic chamber for antenna testing and electromagnetic compatibility testing, so as to form a multifunctional testing system that is compatible with both antenna testing and electromagnetic compatibility testing within the same anechoic chamber space.

[0004] To achieve the above objectives, the embodiments of this application provide the following technical solutions.

[0005] In a first aspect, embodiments of this application provide an absorbing structure for antenna testing and electromagnetic compatibility testing, comprising: a top absorbing structure laid on the top surface of a test anechoic chamber; a bottom absorbing structure laid on the bottom surface of the test anechoic chamber; and four side absorbing structures laid on the four sides of the test anechoic chamber, arranged clockwise as a first absorbing structure, a second absorbing structure, a third absorbing structure, and a fourth absorbing structure; wherein, the first absorbing structure is provided with a high-power absorbing material area for forming a high-power radiation area within the test anechoic chamber; the second, third, and fourth absorbing structures are each provided with a ferrite / flat-top absorbing material area for forming a 10-meter test area within the test anechoic chamber; the remaining areas of the top absorbing structure, the bottom absorbing structure, and the four side absorbing structures are provided with pyramidal absorbing material areas to meet military standard electromagnetic compatibility testing requirements throughout the test anechoic chamber.

[0006] In some embodiments, the material of the high-power absorbing material region is designed to withstand a continuous power density of not less than 5 kW / m².2 High-power absorbing materials.

[0007] In some embodiments, the high-power absorbing material includes a pyramidal body, a honeycomb support, and a surface coating layer.

[0008] In some embodiments, the three ferrite / flat-top absorbing material regions formed by the second, third, and fourth absorbing structures are spatially adjacent to each other and arranged approximately in a U-shape.

[0009] In some embodiments, the material of the ferrite / flat-top absorbing material region is a composite material formed by stacking ferrite absorbing material and flat-top absorbing material, wherein the absorber of the flat-top absorbing material has a truncated cone or cylinder shape.

[0010] In some embodiments, the material of the pyramidal absorbing material region is a pyramidal absorbing material, and the absorber of the pyramidal absorbing material has a cone-shaped shape.

[0011] In some embodiments, both the top and bottom absorbing structures are entirely composed of pyramidal absorbing material regions; and in the four side absorbing structures, the remaining regions, except for the high-power absorbing material region and the ferrite / flat-top absorbing material region, are also composed of pyramidal absorbing material regions.

[0012] In some embodiments, the high-power absorbing material region is a square region with a side length ranging from 9.7m to 10.7m. In the vertical direction, the distance between the lower end of the high-power absorbing material region and the bottom surface of the test anechoic chamber is 2.5m to 3.5m.

[0013] In some embodiments, in the second absorbing structure, the ferrite / flat-top absorbing material area is a rectangular region adjacent to the bottom surface of the test anechoic chamber and the third absorbing structure, with a width ranging from 10.9m to 11.9m and a height ranging from 7.9m to 8.9m; in the third absorbing structure, the ferrite / flat-top absorbing material area is a rectangular region adjacent to the bottom surface of the test anechoic chamber, with a width ranging from 17.5m to 18.5m and a height ranging from 7.9m to 8.9m; in the fourth absorbing structure, the ferrite / flat-top absorbing material is a rectangular region adjacent to the bottom surface of the test anechoic chamber and the third absorbing structure, with a width ranging from 10.9m to 11.9m and a height ranging from 7.9m to 8.9m.

[0014] Secondly, embodiments of this application also provide a test anechoic chamber, including: a top surface, a bottom surface, and four side surfaces; the top surface, bottom surface, and four side surfaces are respectively covered with the wave-absorbing structures used for antenna testing and electromagnetic compatibility testing.

[0015] Compared with the prior art, the absorbing structure and anechoic chamber for antenna testing and electromagnetic compatibility testing provided in this application embodiment adopt different types of absorbing materials to form a multifunctional testing system that is compatible with both antenna testing and electromagnetic compatibility testing in the same anechoic chamber space, thereby improving the utilization rate and testing efficiency of the anechoic chamber and reducing the cost of repeated construction and maintenance of the testing site. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application 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 embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the overall structure of the absorbing structure and anechoic chamber used for antenna testing and electromagnetic compatibility testing according to an embodiment of this application.

[0018] Figure 2 This is a schematic diagram of the arrangement of an absorbing structure for antenna testing and electromagnetic compatibility testing in a test anechoic chamber according to an embodiment of this application.

[0019] Figure 3 This is a schematic diagram of an optional anechoic chamber structure and the arrangement of absorbing materials according to an embodiment of this application.

[0020] Figure 4 This is a schematic diagram of an optional anechoic chamber structure and the arrangement of absorbing materials according to an embodiment of this application.

[0021] Figure 5 This is a schematic diagram of the absorbing material layout of an optional first absorbing structure according to an embodiment of this application.

[0022] Figure 6 This is a schematic diagram of the absorbing material layout of an optional second absorbing structure according to an embodiment of this application.

[0023] Figure 7 This is a schematic diagram of the absorbing material layout of an optional third absorbing structure according to an embodiment of this application.

[0024] Figure 8 This is a schematic diagram of the absorbing material layout of an optional fourth absorbing structure according to an embodiment of this application.

[0025] Figure 9 The normalized site attenuation (NSA) simulation results are shown for the anechoic chamber according to the embodiments of this application.

[0026] Figure 10The simulation results show the site uniformity (FU) of the absorbing anechoic chamber according to the embodiments of this application.

[0027] Figure 11 The simulation results are for the site voltage standing wave ratio (SVSWR) of the anechoic chamber according to the embodiments of this application.

[0028] Figure 12 The measured results of normalized site attenuation (NSA) of the anechoic chamber according to the embodiments of this application are shown.

[0029] Figure 13 The measured results of the site uniformity (FU) of the absorbing anechoic chamber according to the embodiments of this application are shown.

[0030] Figure 14 The above are the measured results of the site voltage standing wave ratio (SVSWR) of the anechoic chamber according to the embodiments of this application. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to limit the application. The singular forms “a,” “said,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0033] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0034] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the article or device that includes said element.

[0035] As described in the background section, existing electromagnetic compatibility anechoic chambers generally suffer from a single function. Most anechoic chambers are designed and optimized only for a certain type of test (such as antenna performance testing or electromagnetic compatibility testing) or a certain standard system (such as military standards or civilian standards), making it difficult to accommodate different test types and test standard systems within the same test space.

[0036] In practical engineering, balancing different test types and standards within the same test space presents substantial technical challenges. This is because the evaluation indicators, site characteristics, selection of absorbing materials, and power handling requirements for different test scenarios vary significantly and can even be mutually restrictive. For example, antenna testing focuses on measuring the antenna's radiation pattern, gain, and polarization characteristics under near-free-space conditions, with extremely high requirements for the suppression of reflected waves and the uniformity of the field distribution. Electromagnetic compatibility testing, on the other hand, focuses on the emission and immunity performance of the device under test, with strict limitations on indicators such as test field strength, background noise, and electromagnetic shielding effectiveness. There are also significant differences between civilian standards and military standards in terms of test frequency bands, field strength range, absorption performance, and power tolerance.

[0037] Therefore, different test types and standard systems impose their own independent constraints on the electromagnetic characteristics of the anechoic chamber. These constraints often differ in the type of absorbing material, its placement, and structural design, and satisfying multiple test types simultaneously cannot be achieved simply by superimposing them.

[0038] To address the aforementioned problems, one aspect of this application provides an absorbing structure for antenna testing and electromagnetic compatibility testing, comprising: a top absorbing structure laid on the top surface of a test anechoic chamber; a bottom absorbing structure laid on the bottom surface of the test anechoic chamber; and four side absorbing structures laid on the four sides of the test anechoic chamber, arranged clockwise as a first absorbing structure, a second absorbing structure, a third absorbing structure, and a fourth absorbing structure; wherein, the first absorbing structure is provided with a high-power absorbing material area to form a high-power radiation area within the test anechoic chamber; the second, third, and fourth absorbing structures are each provided with a ferrite / flat-top absorbing material area to form a 10-meter test area within the test anechoic chamber; the remaining areas of the top absorbing structure, the bottom absorbing structure, and the four side absorbing structures are provided with pyramidal absorbing material areas to meet military standard electromagnetic compatibility testing requirements throughout the test anechoic chamber.

[0039] Compared with the prior art, the absorbing structure and anechoic chamber for antenna testing and electromagnetic compatibility testing provided in this application embodiment adopt different types of absorbing materials to form a multifunctional testing system that is compatible with both antenna testing and electromagnetic compatibility testing in the same anechoic chamber space, thereby improving the utilization rate and testing efficiency of the anechoic chamber and reducing the cost of repeated construction and maintenance of the testing site.

[0040] To enable those skilled in the art to better understand and implement this application, the concept, principles, and advantages of this application are described in detail below through specific embodiments and in conjunction with specific application scenarios and accompanying drawings.

[0041] The absorbing structure for antenna testing and electromagnetic compatibility testing provided in the embodiments of this application will be described in detail below.

[0042] To ensure that the absorbing structure meets both antenna testing and military / civilian electromagnetic compatibility (EMC) testing requirements, it is necessary to comprehensively consider parameters such as absorption performance, shielding effectiveness, background noise, normalized site attenuation (NSA), site voltage standing wave ratio (SVSWR), field uniformity (FU), and power withstand capability. Relevant standards and typical indicators are as follows.

[0043] Regarding the requirements for absorbing materials, GJB151B "Electromagnetic Emission and Sensitivity Requirements and Measurements for Military Equipment and Subsystems" specifies the requirements for the vertical incidence performance of absorbing materials as shown in Table 1.

[0044] Table 1. Vertical incidence performance requirements of absorbing materials in GJB151B

[0045] Frequency (MHz) Absorption loss (dB) 80～250 ≥6 ＞250 ≥10

[0046] Regarding shielding effectiveness requirements, the design of an electromagnetic compatibility anechoic chamber must cover the entire frequency band of the equipment's electromagnetic emissions and interference immunity, with a typical operating range of 10kHz to 40GHz. Within this 10kHz to 40GHz frequency band, different frequency ranges are dominated by different types of electromagnetic fields, and therefore the corresponding shielding requirements also differ. Table 2 lists the shielding performance requirements for different frequency ranges.

[0047] Table 2 Shielding Performance Requirements

[0048]

[0049]

[0050] Regarding background noise requirements, when testing is conducted in a shielded room, with the Equipment Under Test (EUT) powered off and all auxiliary equipment powered on, the measured electromagnetic environment level should be at least 6 dB lower than the specified limit to ensure that background noise does not affect the EUT.

[0051] Regarding Normalized Site Attenuation (NSA), it is an indicator for electromagnetic compatibility (EMC) test sites according to national standards. Testing is conducted in accordance with CISPR 16-1-4, GB / T 6113.104, GJB 2926, and GB 9254-2008 standards. The requirement is that at a test distance of 10m, within the range of 200MHz to 1000MHz, the NSA should be within ±4dB (see relevant provisions in GB / T 6113.104, GJB 2926, and GB 9254-2008).

[0052] Regarding the Site Voltage Standing Wave Ratio (SVSWR), it is required that SVSWR ≤ 6dB in the range of 1GHz to 18GHz (see relevant provisions in GB / T6113.104-2016).

[0053] Regarding field uniformity (FU), it is required that, within the range of 80MHz to 18GHz, the field strength deviation of at least 12 out of 16 test points should be within -0 to +6dB (see relevant provisions of GB / T17626.3-2016).

[0054] Regarding the power handling performance of absorbing materials, in addition to good absorption properties, absorbing materials must also possess sufficient power handling capacity. Unless otherwise specified, ordinary absorbing materials should be able to withstand power densities exceeding 1 kW / m² for continuous waves. 2 High-power absorbing materials should be able to withstand power densities better than 5 kW / m² for continuous waves. 2 .

[0055] To meet and accommodate the various standards for antenna testing and military and civilian electromagnetic compatibility testing, this application provides an absorbing structure for antenna testing and electromagnetic compatibility testing. This absorbing structure forms multiple functional areas in the same anechoic chamber by setting absorbing materials with different absorption properties on the inner surface of the anechoic chamber. These areas can be used for military standard electromagnetic compatibility testing, 10-meter method testing required by national standards, and antenna performance or high-power radiation testing.

[0056] like Figure 1As shown, the absorbing structure is placed on the inner surface of the test chamber. The test chamber includes a top surface (not shown), a bottom surface (not shown), and four sides, which are arranged clockwise as first side 11, second side 12, third side 13, and fourth side 14. These surfaces together form the overall framework of the test space. Specifically, the top surface of the test chamber is covered with a top absorbing structure (not shown) to absorb electromagnetic wave energy from below, reducing top surface reflection; the bottom surface of the test chamber is covered with a bottom absorbing structure (not shown) to absorb electromagnetic wave energy from above, reducing bottom surface reflection; the first side 11 is covered with a first absorbing structure 110, the second side 12 with a second absorbing structure 120, the third side 13 with a third absorbing structure 130, and the fourth side 14 with a fourth absorbing structure 140.

[0057] For ease of explanation, in some specific embodiments of this application, the first side 11 corresponds to the north side, also known as the north wall; the second side 12 corresponds to the east side, also known as the east wall; the third side 13 corresponds to the south side, also known as the south wall; and the fourth side 14 corresponds to the west side, also known as the west wall. Correspondingly, the first absorbing structure 110 is installed on the north wall of the test anechoic chamber, the second absorbing structure 120 is installed on the east wall of the test anechoic chamber, the third absorbing structure 130 is installed on the south wall of the test anechoic chamber, and the fourth absorbing structure 140 is installed on the west wall of the test anechoic chamber. It should be understood that the above orientation relationships are merely exemplary descriptions used to facilitate the explanation of the structural arrangement of the embodiments of the present invention. This application does not limit the specific orientation of the test anechoic chamber; other implementations with the same functional layout but different orientations may also be adopted.

[0058] like Figure 2 As shown, the first absorbing structure 110, the second absorbing structure 120, the third absorbing structure 130, and the fourth absorbing structure 140 adopt different types of absorbing materials according to the corresponding test requirements, so as to form a multi-functional test system for compatible antenna testing and electromagnetic compatibility testing in the same test anechoic chamber space.

[0059] Specifically, the first absorbing structure 110 is provided with a high-power absorbing material region 101, which is used to form a high-power radiation region 21 in a specific area of ​​the test anechoic chamber, so as to achieve efficient absorption and reflection suppression of high-power electromagnetic waves, thereby meeting the requirements of antenna testing and high-power radiation testing.

[0060] The high-power absorbing material region 101 is made of high-power absorbing material, which possesses high power carrying capacity, wide bandwidth absorption characteristics, and excellent heat dissipation performance. The high-power absorbing material can continuously withstand power loads of not less than 5kW / m². 2 The power density is designed to meet the environmental requirements for high-power radiation testing.

[0061] In some embodiments, the high-power absorbing material is a honeycomb high-power pyramidal absorbing material, which includes a pyramidal body, a honeycomb support, and a surface coating layer. The pyramidal body is made of polyurethane foam containing conductive filler, and the honeycomb support forms periodic polygonal channels to extend the propagation path of electromagnetic waves within the material and improve mechanical strength and heat dissipation performance. The surface coating layer is used for impedance matching and moisture and dust protection. As a specific example, the honeycomb high-power pyramidal absorbing material can be selected from aerospace long-screen honeycomb high-power polyurethane pyramidal absorbing material BPFWE-700.

[0062] The first absorbing structure 110, excluding the high-power absorbing material region 101, has pyramidal absorbing material regions 102 in other areas. Specifically, in the first absorbing structure 110, the high-power absorbing material region 101 is located in the lower central region, and pyramidal absorbing material regions 102 are provided around the high-power absorbing material region 101 to ensure both high-power absorption capability and field uniformity of the test space. In some embodiments, all areas of the first absorbing structure 110 except for the high-power absorbing material region 101 are composed of pyramidal absorbing material regions. In some embodiments, the high-power absorbing material region 101 is a square region with a side length ranging from 9.7m to 10.7m, and the distance between the lower end of the high-power absorbing material region 101 and the bottom surface of the test anechoic chamber in the vertical direction is 2.5m to 3.5m.

[0063] The pyramidal absorbing material region 102 is made of pyramidal absorbing material, which possesses broadband absorption characteristics and excellent impedance matching performance, used to improve the overall absorption effect and field distribution uniformity within the test anechoic chamber. The absorber of the pyramidal absorbing material has a cone-shaped profile, meaning the absorber unit gradually tapers from the inner wall towards the test space, forming a continuous impedance gradient to reduce electromagnetic wave reflection at the incident interface and enhance absorption efficiency. The matrix of the pyramidal absorbing material can be made of polyurethane foam containing conductive filler, and a coating layer can be applied to the surface of the pyramid to achieve incident wave impedance matching and moisture and dust protection. As an example, the pyramidal absorbing material can be aerospace-grade long-screen coated polyurethane pyramidal absorbing material BPUFA-C700 or BPUFA-W700.

[0064] Each of the second absorbing structure 120, the third absorbing structure 130, and the fourth absorbing structure 140 is provided with a ferrite / flat-top absorbing material region 103. These three ferrite / flat-top absorbing material regions 103 are spatially adjacent and arranged approximately in a U-shape to form a 10-meter test area 22, meeting the performance requirements of civilian standards such as field uniformity (FU), normalized field attenuation (NSA), and voltage standing wave ratio (SVSWR). Furthermore, in the areas of the second absorbing structure 120, the third absorbing structure 130, and the fourth absorbing structure 140 other than the ferrite / flat-top absorbing material region 103, pyramidal absorbing material regions 102 are provided to improve the overall absorption performance and electromagnetic field uniformity of the test space, ensuring that reflection control and background noise levels throughout the entire anechoic chamber meet the requirements of military standard electromagnetic compatibility testing. In some embodiments, the second absorbing structure 120, the third absorbing structure 130, and the fourth absorbing structure 140, except for the ferrite / flat-top absorbing material region 103, are all composed of pyramidal absorbing material regions.

[0065] The ferrite / flat-top absorbing material region 103 is made of a composite material formed by layering ferrite absorbing material and flat-top absorbing material. This composite material includes layered ferrite absorbing material and flat-top absorbing material. Ferrite absorbing material is mainly used for absorbing low-frequency electromagnetic waves, reducing their reflection and propagation. Flat-top absorbing material is mainly used for absorbing mid-to-high-frequency electromagnetic waves. The absorber of the flat-top absorbing material has a truncated cone or cylinder shape, meaning the upper end of the absorber is approximately planar. This flat-top design helps provide uniform absorption performance and reduce electromagnetic wave reflection. In some embodiments, polyurethane flat-top absorbing material can be used. The flat-top absorbing material and ferrite absorbing material can be bonded or hot-pressed to form a strong laminated structure. As a specific example, the ferrite absorbing material can be Korean Pear Tree TM55 Tile 52; the flat-top absorbing layer can be Aerospace Long Screen Polyurethane Flat-Top Absorbing Material BPUFA-FP-C700.

[0066] Both the top and bottom absorbing structures are provided with pyramidal absorbing material areas. In some embodiments, both the top and bottom absorbing structures are entirely composed of pyramidal absorbing material areas, meaning that the entire inner surface of the top and bottom surfaces of the test chamber is covered with pyramidal absorbing material. The top and bottom absorbing structures are entirely composed of pyramidal absorbing material, forming a symmetrical pyramidal absorbing interface. Furthermore, the remaining areas of the four side absorbing structures, except for specific functional areas (including the high-power absorbing material area 101 and the ferrite / flat-top absorbing material area 103), are also composed of pyramidal absorbing material areas, ensuring that the entire test space meets the requirements of military standard electromagnetic compatibility testing for background noise and field uniformity.

[0067] In some embodiments, in the second absorbing structure 120, the ferrite / flat-top absorbing material region 103 is a rectangular region with a width ranging from 10.9m to 11.9m and a height ranging from 7.9m to 8.9m. The lower end of the rectangle is adjacent to the bottom surface of the test anechoic chamber, and the right edge of the rectangle is adjacent to the third absorbing structure 130. In the third absorbing structure 130, the ferrite / flat-top absorbing material region 103 is a rectangular region with a width ranging from 17.5m to 18.5m and a height ranging from 7.9m to 8.9m. The lower end of the rectangle is adjacent to the bottom surface of the test anechoic chamber. In the fourth absorbing structure 140, the ferrite / flat-top absorbing material area 103 is a rectangular area with a width ranging from 10.9m to 11.9m and a height ranging from 7.9m to 8.9m. The lower end of the rectangle is adjacent to the bottom surface of the test anechoic chamber, and the left edge of the rectangle is adjacent to the third absorbing structure 130.

[0068] Example 1

[0069] To enable those skilled in the art to better understand the technical solution of this application, the following is combined with... Figures 3 to 8 This application provides a detailed description of an absorbing structure and an anechoic chamber for antenna testing and electromagnetic compatibility testing, as provided in the embodiments of this application.

[0070] like Figure 3 and Figure 4 As shown, the interior of the test anechoic chamber in this embodiment is composed of multiple functional areas formed by a combination of different types of absorbing structures, namely: high-power radiation area 21, 10-meter method test area 22, military standard test table area 23, and whole satellite test area 24.

[0071] The high-power radiation region 21 is formed by a high-power absorbing material region 101 (marked in red in the figure) located on the north wall of the anechoic chamber. The high-power absorbing material region 101 is used to absorb high-intensity electromagnetic radiation energy within this region. The high-power absorbing material region 101 uses honeycomb high-power pyramidal absorbing material, which has high power carrying capacity and excellent heat dissipation performance, and can continuously withstand a power density of not less than 5 kW / m². 2 This is to meet the environmental requirements for high-power antenna radiation testing. A pyramidal absorbing material region 102 (marked in dark blue in the figure) is provided around the high-power absorbing material region 101.

[0072] The 10-meter method test area 22 is formed by three ferrite / flat-top absorbing material zones 103 (marked in light blue in the figure) located on the east, south, and west walls of the test anechoic chamber. These three ferrite / flat-top absorbing material zones 103 are spatially adjacent and arranged approximately in a U-shape to create a 10-meter method electromagnetic compatibility test site that meets national standards within the test anechoic chamber. A pyramidal absorbing material zone 102 (marked in dark blue in the figure) is positioned around each of the ferrite / flat-top absorbing material zones 103.

[0073] In addition, the anechoic chamber is further equipped with a power amplifier room and a control room to provide signal drive and system control for different test scenarios. The anechoic chamber also includes a military standard test table area 23 for conducting military standard electromagnetic compatibility tests. The military standard test table area 23 is located near the west side of the anechoic chamber, adjacent to the power amplifier room and control room, facilitating the connection and switching of test equipment with external signal sources. The military standard test table area 23 is surrounded by pyramidal absorbing material 102. During testing, the device under test (EUT) can be placed on the military standard test table, and combined with the RF signal source provided by the power amplifier room and the monitoring terminal in the control room, multiple tests such as transmission, interference immunity, shielding, and electromagnetic susceptibility can be performed. A whole-satellite test area 24 is located in the center of the anechoic chamber for conducting whole-system electromagnetic compatibility tests on large equipment or satellite systems.

[0074] like Figure 5 As shown, the north wall of the test anechoic chamber is composed of a high-power absorbing material area 101 (marked with a red grid in the figure) and surrounding pyramidal absorbing material areas 102 (marked with a dark blue grid in the figure). The high-power absorbing material area 101 is located slightly below the center of the north wall, corresponding to the high-power radiation area 21 within the test anechoic chamber; the pyramidal absorbing material areas 102 are distributed throughout the remaining areas of the north wall. The figure also provides specific parameters for each area. For example, the high-power absorbing material area 101 is a 10200mm × 10200mm rectangle. Vertically, the bottom of the rectangle is approximately 3000mm from the bottom surface, and horizontally, the rectangle is centered, with both ends 9600mm from the edge of the north wall. Shielding doors (marked with a pink grid in the figure) and air conditioning return air vents (marked with a solid yellow body in the figure) can also be installed on the north wall. It should be noted that… Figure 5 The train tracks and related areas shown in the other accompanying drawings are only used to illustrate an instance arrangement in a specific engineering application and are not structural components that are required by this application.

[0075] like Figure 6As shown, the east wall of the test chamber is composed of a ferrite / flat-top absorbing material area 103 (shown as a light gray area in the figure) and a pyramidal absorbing material area 102 (marked as a dark blue grid in the figure). The ferrite / flat-top absorbing material area 103 is located at the lower part of the east wall and is adjacent to the south wall, while the pyramidal absorbing material area 102 is distributed in the remaining areas of the east wall. The figure also shows the specific parameters of each area. For example, the ferrite / flat-top absorbing material area 103 is a rectangle with a width of 11400mm and a height of 8400mm. In the vertical direction, the bottom of the rectangle is about 0mm from the bottom surface, and in the horizontal direction, the edge of the rectangle is about 0mm from the south wall.

[0076] like Figure 7 As shown, the south wall of the test chamber is composed of a ferrite / flat-top absorbing material area 103 (shown as a light gray area in the figure) and a pyramidal absorbing material area 102 (marked as a dark blue grid in the figure). The ferrite / flat-top absorbing material area 103 is located in the central area of ​​the lower part of the south wall, while the pyramidal absorbing material areas 102 are distributed in the remaining areas of the south wall. The figure also shows the specific parameters of each area. For example, the ferrite / flat-top absorbing material area 103 is a rectangle with a length of 18000mm and a height of 8400mm. In the vertical direction, the bottom end of the rectangle is about 0mm from the bottom surface, and in the horizontal direction, the two sides of the rectangle are about 6000mm from the edge of the south wall.

[0077] like Figure 8 As shown, the west wall of the test chamber is composed of a ferrite / flat-top absorbing material area 103 (shown as a light gray area in the figure) and a pyramidal absorbing material area 102 (marked as a dark blue grid in the figure). The ferrite / flat-top absorbing material area 103 is located at the lower part of the west wall and is adjacent to the south wall, while the pyramidal absorbing material area 102 is distributed in the remaining areas of the west wall. The figure also shows the specific parameters of each area. For example, the ferrite / flat-top absorbing material area 103 is a rectangle with a length of 11400mm and a height of 8400mm. In the vertical direction, the bottom of the rectangle is about 0mm from the bottom surface, and in the horizontal direction, the edge of the rectangle is about 0mm from the south wall.

[0078] According to another aspect of the embodiments of this application, a test anechoic chamber is also provided, comprising: a top surface, a bottom surface, and four side surfaces 11-14; the inner surfaces of the top surface, bottom surface, and four side surfaces 11-14 are respectively covered with the aforementioned absorbing structures for antenna testing and electromagnetic compatibility testing. Specifically, the top surface and bottom surface of the test anechoic chamber are respectively provided with a top absorbing structure and a bottom absorbing structure, and the four side surfaces 11-14 of the test anechoic chamber are sequentially provided with a first absorbing structure 110, a second absorbing structure 120, a third absorbing structure 130, and a fourth absorbing structure 140.

[0079] The aforementioned structural arrangement allows the anechoic chamber to perform multiple testing functions within the same space, including antenna performance testing, military standard and civilian standard electromagnetic compatibility testing, etc. The absorbing structure employs different combinations of absorbing materials at different wall locations to create multiple functional areas within the anechoic chamber, such as high-power radiation area 21, 10-meter method testing area 22, and military standard testing areas 23 and 24. This enables multi-scenario electromagnetic environment control within the same testing space, significantly improving testing efficiency and saving testing space.

[0080] Compared with the prior art, the absorbing structure and anechoic chamber for antenna testing and electromagnetic compatibility testing provided in this application embodiment adopt different types of absorbing materials to form a multifunctional testing system that is compatible with both antenna testing and electromagnetic compatibility testing in the same anechoic chamber space, thereby improving the utilization rate and testing efficiency of the anechoic chamber and reducing the cost of repeated construction and maintenance of the testing site.

[0081] To verify the shielding performance and site characteristics of the test anechoic chamber described in the embodiments of this application, electromagnetic compatibility simulation calculations were performed on the overall structure of the test anechoic chamber disclosed in Embodiment 1.

[0082] To assess the overall shielding performance of the anechoic chamber, its shielding effectiveness (SE) is calculated. Shielding effectiveness characterizes the attenuation capability of the shielding structure against external electromagnetic fields, and its calculation formula is as follows:

[0083]

[0084] Simulation calculations show that the shielding effectiveness of the anechoic chamber described in Example 1 meets the standard requirements in the 10kHz to 40GHz frequency band, as shown in Table 3.

[0085] Table 3

[0086] frequency Shielding effectiveness field 10kHz ≥70dB magnetic field 1MHz ≥90dB magnetic field 1MHz~100MHz ≥100dB electric field 100MHz~1GHz ≥100dB plane wave 1GHz~18GHz ≥90dB microwave 18GHz~40GHz ≥80dB microwave

[0087] As can be seen from the above results, the test anechoic chamber provided in this application can maintain high shielding effectiveness throughout the entire operating frequency band, fully meeting the requirements of relevant standards such as GJB151B and GB / T 6113.104 for shielding performance of magnetic fields, electric fields and plane waves.

[0088] Specifically, the normalized site attenuation (NSA) was simulated, and the simulation results are shown below. Figure 9The NSA distributions are presented for horizontal polarization with antenna heights of 1m and 2m, and for vertical polarization with antenna heights of 1m and 1.5m. The vertical axis represents the NSA error, with corresponding limits of +4dB and -4dB, respectively. Simulation results show that, regardless of horizontal or vertical polarization, the curves at each measurement point fluctuate within the ±4dB limit, exhibiting stable overall distribution and meeting the relevant standards for NSA performance.

[0089] Specifically, the site uniformity (FU) was simulated, and the simulation results are shown below. Figure 10 The field uniformity data distribution under horizontal and vertical polarization conditions are presented respectively. The vertical axis represents the field strength deviation, with corresponding limits of +6dB and 0dB, respectively. The simulation results show that under both horizontal and vertical polarization conditions, the field strength deviation at the test points is distributed within the limit range, indicating that the electromagnetic field distribution inside the anechoic chamber is uniform and meets the relevant standards for FU (Full Electromagnetic Field).

[0090] Specifically, the site voltage standing wave ratio (SVSWR) was simulated and calculated. The simulation results are shown below. Figure 11 The field voltage standing wave ratio (SVSWR) distributions under horizontal and vertical polarization conditions are presented, with the horizontal axis representing frequency and the vertical axis representing the SVSWR value, corresponding to limits of +6 dB and 0 dB, respectively. The simulation results show that under both horizontal and vertical polarization conditions, the SVSWR values ​​in all directions remain within the limits and are far below the +6 dB limit, indicating low electromagnetic wave reflection and a low SVSWR inside the anechoic chamber, meeting the relevant standards for SVSWR.

[0091] Furthermore, the overall performance of the electromagnetic compatibility test anechoic chamber constructed using the absorbing structure described in this application was evaluated and tested. The testing unit was the Beijing Radio Metrology Institute, and the testing content included normalized site attenuation (NSA, see [link]). Figure 12 ), site uniformity (FU, see Figure 13 ) and site voltage standing wave ratio (SVSWR, see Figure 14 Actual test results show that the anechoic chamber described in this embodiment of the invention has excellent electromagnetic shielding performance, low reflection characteristics and high field uniformity within the test frequency range, and can meet the requirements of various tests such as antenna testing, whole satellite testing and military and civilian standard electromagnetic compatibility testing.

[0092] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus described in the embodiments, since they correspond to the methods described in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0093] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An absorbing structure for antenna testing and electromagnetic compatibility testing, characterized in that, The application relates to a wave-absorbing structure for antenna testing and electromagnetic compatibility testing. The wave-absorbing structure comprises: a top wave-absorbing structure arranged on the top surface of the test darkroom; a bottom wave-absorbing structure arranged on the bottom surface of the test darkroom; and four side wave-absorbing structures arranged on the four side surfaces of the test darkroom in a clockwise order, namely a first wave-absorbing structure, a second wave-absorbing structure, a third wave-absorbing structure and a fourth wave-absorbing structure. The first wave-absorbing structure is provided with a high-power wave-absorbing material area for forming a high-power radiation area in the test darkroom; the second wave-absorbing structure, the third wave-absorbing structure and the fourth wave-absorbing structure are respectively provided with ferrite / flat-head type wave-absorbing material areas for forming a 10-meter method test area in the test darkroom; and the remaining areas of the top wave-absorbing structure, the bottom wave-absorbing structure and the four side wave-absorbing structures are provided with pyramid type wave-absorbing material areas for meeting the military standard electromagnetic compatibility test requirements in the whole test darkroom.

2. The wave-absorbing structure for antenna test and electromagnetic compatibility test according to claim 1, characterized in that, The material of the high-power wave-absorbing material area adopts a high-power wave-absorbing material that continuously bears a power density of not less than 5 kW / m 2 .

3. The wave-absorbing structure for antenna test and electromagnetic compatibility test according to claim 2, characterized in that, The high-power wave-absorbing material comprises a pyramid main body, a honeycomb support body and a surface coating layer.

4. The wave-absorbing structure for antenna testing and electromagnetic compatibility testing according to claim 1, characterized in that, The three ferrite / flat-head type wave-absorbing material areas formed by the second wave-absorbing structure, the third wave-absorbing structure and the fourth wave-absorbing structure are adjacent to each other in space and arranged in a U shape.

5. The wave-absorbing structure for antenna test and electromagnetic compatibility test according to claim 1 or 4, characterized in that, The material of the ferrite / flat-head type wave-absorbing material area is a composite material formed by laminating ferrite wave-absorbing material and flat-head type wave-absorbing material, wherein the wave-absorbing body of the flat-head type wave-absorbing material is in the shape of a truncated cone or a truncated column.

6. The wave-absorbing structure for antenna testing and electromagnetic compatibility testing according to claim 1, characterized in that, The material of the pyramid type wave-absorbing material area is a pyramid type wave-absorbing material, and the wave-absorbing body of the pyramid type wave-absorbing material is in the shape of a cone.

7. The wave-absorbing structure for antenna test and electromagnetic compatibility test according to claim 1 or 6, characterized in that, The top wave-absorbing structure and the bottom wave-absorbing structure are both composed of pyramid type wave-absorbing material areas; and the remaining areas of the four side wave-absorbing structures, except the high-power wave-absorbing material area and the ferrite / flat-head type wave-absorbing material area, are also composed of pyramid type wave-absorbing material areas.

8. The wave-absorbing structure for antenna testing and electromagnetic compatibility testing according to claim 1, characterized in that, The high-power wave-absorbing material area is a square area, and the length of the square side ranges from 9.7m to 10.7m; and in the vertical direction, the distance between the lower end of the high-power wave-absorbing material area and the bottom surface of the test darkroom ranges from 2.5m to 3.5m.

9. The wave-absorbing structure for antenna testing and electromagnetic compatibility testing according to claim 1 or 8, wherein in the second wave-absorbing structure, the ferrite / flat-head type wave-absorbing material area is a rectangular area adjacent to the bottom surface of the test darkroom and the third wave-absorbing structure, and the width ranges from 10.9m to 11.9m and the height ranges from 7.9m to 8.9m; in the third wave-absorbing structure, the ferrite / flat-head type wave-absorbing material area is a rectangular area adjacent to the bottom surface of the test darkroom, and the width ranges from 17.5m to 18.5m and the height ranges from 7.9m to 8.9m; in the fourth wave-absorbing structure, the ferrite / flat-head type wave-absorbing material area is a rectangular area adjacent to the bottom surface of the test darkroom and the third wave-absorbing structure, and the width ranges from 10.9m to 11.9m and the height ranges from 7.9m to 8.9m.

10. A test darkroom, comprising: a top surface, a bottom surface and four side surfaces; the top surface, the bottom surface and the four side surfaces are respectively arranged with the wave-absorbing structure for antenna testing and electromagnetic compatibility testing according to any one of claims 1-9.

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