A low-scattering joint carrier that takes into account RCS testing of multiple finished parts

Abstract

The present invention provides a low-scattering combined carrier that takes into account RCS tests of multiple finished parts, and belongs to the field of electromagnetic scattering measurement. The low-scattering combined carrier is a seamlessly connected teardrop-shaped hollow structure, and three flange interfaces are arranged on its upper surface for connecting the test component. It is designed as an integrated structure with the test component, and is smoothly and tightly connected, which not only eliminates the edge scattering of the tested component, but also shields the inner cavity structure of the component, and better simulates the state of the component when it is actually installed, so that the tested component can be more accurately measured and evaluated for RCS. The low-scattering combined carrier also includes an absorbing sleeve, whose inner surface fits the outer surface of the carrier, and is used for low-frequency RCS testing below S. The present invention can evaluate the RCS of a single tested component individually, and can also jointly evaluate the RCS of three tested components, which solves the problem that it is difficult to take into account the joint evaluation of RCS of multiple test components.

Description

Technical Field

[0001] The invention belongs to the field of electromagnetic scattering measurement, and in particular relates to a low-scattering joint carrier that takes into account RCS (Radar Cross Section) tests of multiple finished parts. Background Art

[0002] The development process of stealth aircraft involves performance tests of multiple stealth finished parts. Once the test piece is separated from the stealth body, the test piece is exposed to electromagnetic waves, and the scattering caused by its edges and internal structure will affect the accuracy of the test. Therefore, it is necessary to design a low-scattering carrier to eliminate the edge scattering of the test piece and shield the internal structure of the test piece. The electromagnetic scattering of a low-scattering carrier is generally 1 to 2 orders of magnitude lower than that of the test piece. The RCS of the test piece can be reflected by installing the test piece on the carrier.

[0003] The current low-scatter carrier is basically designed for low scattering of only one test piece, but there are dozens of aircraft products, and a low-scatter carrier needs to be designed separately for each one, which increases the development capital and time cost of stealth target carrier design. Therefore, in view of the shortcomings of the existing single low-scatter carrier design, it is necessary to provide a low-scatter joint carrier that can take into account multiple stealth test pieces, so as to obtain the RCS performance of multiple test pieces at the same time. This not only reduces the design and manufacturing costs, but also reduces the workload of replacing the carrier during testing, greatly improving work efficiency.

[0004] Publication number CN109212504A, publication date January 15, 2019, the invention patent named "Low scattering carrier with both forward and lateral design" discloses a low scattering carrier and test method with both forward and lateral design. Its advantages are good surface current guiding effect, effective reduction of the contribution of traveling wave scattering, and low scattering level in both forward and lateral directions. Its disadvantage is that it is only for RCS testing of a single test piece, and it is difficult to take into account the joint testing of multiple test pieces.

[0005] The invention patent with publication number CN111504952A and publication date August 7, 2020, entitled "A low-scattering carrier that takes into account both horizontal and vertical polarizations and its test method", solves the problem that the existing low-scattering carrier cannot take into account both horizontal and vertical polarizations well, and can have lower backscattering in a larger angle range. Similarly, its disadvantage is that it is difficult to take into account the joint test of multiple test pieces for the RCS test of a single test piece. Summary of the invention

[0006] The present invention provides a low-scattering joint carrier that takes into account RCS tests of multiple finished parts, including a low-scattering joint carrier that takes into account RCS tests of multiple test pieces, which is designed with an integrated structure with the test component, and is smoothly and tightly connected, which not only eliminates the edge scattering of the tested component, but also shields the internal cavity structure of the component, and better simulates the state of the component when it is actually installed, so that the tested component can be more accurately measured and evaluated for RCS. The problem that the existing low-scattering carrier only evaluates the RCS of a single test piece and cannot better take into account the joint evaluation of multiple tested pieces is solved.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is:

[0008] A low-scattering combined carrier that takes into account RCS tests of multiple finished parts, the low-scattering combined carrier comprises: a main carrier, a test calibration block 9, a supporting shaping foam 10, an elevation adjustment foam 11 and an absorbing sleeve.

[0009] The main carrier includes a left side surface 1, a right side surface 2, a rear side surface 3, an upper surface 4, a lower surface 5, a flange interface 1 6, a flange interface 2 7, and a flange interface 3 8; the upper surface 4 and the lower surface 5 are both smooth curved surfaces, which are seamlessly connected with the left side surface 1, the right side surface 2 and the rear side surface 3 in a gradient radius transition manner, and together form the outer contour of the main carrier; the main carrier is a hollow structure, shaped like a water drop with a pointed cone end, and is bilaterally symmetrical. The curved surface of the main carrier along the length and width directions has a continuous curvature at the joint to reduce the backscattering of the traveling wave; the edge of the main carrier adopts a gradient radius transition curved surface to reduce edge scattering and surface wave backscattering.

[0010] Three flange interfaces are arranged in the middle of the upper surface 4: flange interface 1 6, flange interface 2 7 and flange interface 3 8, which are respectively used to install the components for RCS test. The edges of the three flange interfaces are provided with depressions, which are lower than the upper surface 4 of the main carrier. Several countersunk holes are arranged in the depressions for installing the components to be tested. After installation, the bottom edge of the components to be tested is flush with the upper surface 4. The components to be tested are installed at the corresponding flange interfaces by countersunk screws; after installation, the head direction of the components to be tested is consistent with the forward direction of the main carrier (i.e. the direction of the pointed cone end), the bottom edge of the components to be tested (i.e. the upper surface of the mounting seat of the components to be tested) is flush with the upper surface 4, and the gap between the bottom of the components to be tested and the upper surface 4 is pasted with aluminum foil.

[0011] The absorbing sleeve is composed of a low-frequency left front absorbing sleeve 12, a low-frequency left rear absorbing sleeve 13, a low-frequency right front absorbing sleeve 14 and a low-frequency right rear absorbing sleeve 15. The absorbing sleeve is a hollow structure, a water drop shape with a tip, bilaterally symmetrical, and a smooth curved surface. Its inner side is in contact with the outer side of the main carrier, and an opening is provided in the middle of the upper surface of the absorbing sleeve to avoid the three flange interfaces on the main carrier. During installation, the low-frequency left front absorbing sleeve 12, the low-frequency left rear absorbing sleeve 13, the low-frequency right front absorbing sleeve 14 and the low-frequency right rear absorbing sleeve 15 are respectively assembled on the main carrier and pasted together for low-frequency RCS testing below S. When testing below the S band, the absorbing sleeve needs to be assembled on the main carrier, and the inner surface of the absorbing sleeve is in contact with the outer side of the main carrier.

[0012] The supporting shaped foam 10 is a truncated cone structure, which is placed under the main carrier or the main carrier with an absorbing sleeve, and is used to place the tested component in the test posture during darkroom testing. The elevation adjustment foam 11 is a truncated cone structure with a certain inclination angle, which is placed under the supporting shaped foam 10 and is used to adjust the pitch angle.

[0013] The test calibration block 9 matches the main carrier and is placed at the set position of the central axis in the front part of the upper surface 4 of the main carrier when in use. Its upper surface is a plane and is used in conjunction with a level placed thereon to test the actual placement attitude angle of the main carrier.

[0014] Furthermore, the pointed cone end of the outer contour of the main carrier is chamfered, and the radius of the chamfer is less than 1 mm. If the chamfer radius of the pointed cone end is too large, it will cause mirror reflection of the main carrier head.

[0015] Furthermore, the forward inner angle of the main carrier (i.e., the angle between the two side edges of the upper surface 4 close to the pointed cone end) is 54±5°. When the electromagnetic wave is vertically incident on the side edge of the main carrier, the mirror reflection wave peak is outside the forward RCS key reduction angle region.

[0016] Furthermore, the surface roughness Ra of the upper surface 4 and the lower surface 5 is less than 1.6.

[0017] Furthermore, the low-scattering combined carrier has a length of 2000 mm to 2100 mm, a width of 600 mm to 700 mm, and a height of 220 mm.

[0018] Furthermore, the low-scattering joint carrier can evaluate the RCS performance of a component individually through a sealing process, and can also perform a joint evaluation on three components under test at the same time.

[0019] The design mechanism of the high frequency band of the low scattering combined carrier of the present invention is based on the shape stealth method, so that the surface produces strong scattering such as mirror reflection, multiple reflection and edge diffraction to deviate from the threat angle domain. The low scattering combined carrier can have a good surface current guiding effect by adjusting the angle between its two side edges by design, and combined with the arc-shaped transition form of the upper surface 4 and the lower surface 5 of the carrier, thereby reducing the contribution of traveling wave scattering, and effectively avoiding the fluctuation of the carrier RCS in the low scattering angle domain. The backscattering caused by the traveling wave current can be significantly weakened by the shape of the low scattering combined carrier.

[0020] The low scattering technology achieved by relying on the shape is only effective for radar waves with shorter wavelengths. Therefore, the design mechanism of the low scattering joint carrier of the present invention below the S band uses the electromagnetic wave absorbing effect of the absorbing sleeve to dissipate the edge traveling waves, suppress the edge traveling wave scattering, and obtain low RCS characteristics.

[0021] The RCS of the low-scattering combined carrier is more than 10-20 dBsm lower than the RCS of the test target component, thereby achieving low backscattering of the carrier in a large angle range in both directions.

[0022] During installation, the components to be tested are installed on flange interface 6, flange interface 7 and flange interface 8 respectively by countersunk screws. After installation, the bottom edge of the component to be tested is flush with the upper surface 4, and the gap between the bottom of the component to be tested and the upper surface 4 and the screws are pasted with aluminum foil or conductive adhesive. In this way, the edge and embedded structure of the component to be tested are shielded by the carrier, and the RCS of multiple components can be accurately measured.

[0023] When testing below the S-band, it is necessary to install an absorbing sleeve. The low-frequency left front absorbing sleeve 12, the low-frequency left rear absorbing sleeve 13, the low-frequency right front absorbing sleeve 14, and the low-frequency right rear absorbing sleeve 15 are respectively assembled on the two sides of the carrier and bonded with American paper tape so that the outer edge of the carrier is buried in the absorbing sleeve structure to suppress low-frequency traveling wave scattering. The RCS below the S-band of the low-scattering combined carrier can be accurately measured.

[0024] During the test, the supporting shaping foam 10 and the elevation adjustment foam 11 cooperate to adjust the test angle, and the test calibration block 9 is placed at the set position in front of the upper surface 4 of the low-scattering combined carrier. The actual posture angle of the low-scattering combined carrier is tested in conjunction with a spirit level to accurately measure the posture placement angle during the test to ensure that the test posture angle error is no more than 0.1°.

[0025] When the low-scattering combined carrier measures the RCS performance of a certain component alone, aluminum foil or conductive glue is pasted on two flange interfaces outside the measured component to perform cavity sealing treatment. The surface of the carrier after the cavity sealing treatment is similar to a metal surface, so that the RCS of the measured component can be accurately tested.

[0026] Beneficial effects of the present invention:

[0027] The low-scattering combined carrier provided by the present invention can eliminate the edge scattering of the component, shield the inner cavity structure of the component, better simulate the state of the component when it is actually installed, and at the same time has low backscattering within a large angle range, and will not affect the RCS test of the component, so that the component can be measured and evaluated for RCS more accurately.

[0028] The present invention can evaluate the RCS of a single device under test separately, and can also jointly evaluate the RCS of three devices under test, thus solving the problem of difficulty in taking into account the joint evaluation of RCS of multiple test devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 4 is a top view of a low-scattering combined carrier according to an embodiment of the present invention.

[0030] Figure 2 4 is a side view of a low-scattering combined carrier according to an embodiment of the present invention.

[0031] Figure 3 It is an oblique view of the low-scattering combined carrier according to an embodiment of the present invention.

[0032] Figure 4 It is a side view of a low-scattering combined carrier covered with an absorbing sleeve according to an embodiment of the present invention.

[0033] Figure 5 This is an oblique view of the low-scatter joint carrier after the support foam and the posture adjustment foam are assembled.

[0034] Figure 6 It is an oblique view of the low-scatter joint carrier attitude angle measurement according to an embodiment of the present invention.

[0035] In the figure: 1 left side surface; 2 right side surface; 3 rear side surface; 4 upper surface; 5 lower surface; 6 flange interface one; 7 flange interface two; 8 flange interface three; 9 test calibration block; 10 supporting shaping foam; 11 elevation adjustment foam; 12 low-frequency left front absorbing sleeve; 13 low-frequency left rear absorbing sleeve; 14 low-frequency right front absorbing sleeve; 15 low-frequency right rear absorbing sleeve. DETAILED DESCRIPTION

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. It should be understood that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and therefore should not be regarded as limiting the scope of protection. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technical personnel in this field without making creative work are within the scope of protection of the present invention.

[0037] Example

[0038] After the overall stealth shape design of the aircraft is completed, the stealth performance test of each component will be considered. Once the component under test is separated from the fuselage, the edge and embedded structure of the component under test will be exposed. If the component is tested without any treatment, the scattering of its edge and embedded structure will affect the test accuracy of the component. Therefore, a low-scattering joint carrier is designed to block the edge and embedded structure of the component under test to avoid scattering caused by the edge and embedded structure of the component under test, which affects the test accuracy of the component RCS. Considering cost reduction and efficiency improvement, a low-scattering joint carrier is designed to take into account the RCS testing of multiple finished parts.

[0039] The structure of the low scattering combined carrier is shown in Figures 1 to 3 , including a main carrier, a test calibration block 9, a supporting shaping foam 10, an elevation adjustment foam 11 and an absorbing sleeve.

[0040] The main carrier includes a left side surface 1, a right side surface 2, a rear side surface 3, an upper surface 4, a lower surface 5, a flange interface 1 6, a flange interface 2 7, and a flange interface 3 8; the upper surface 4 and the lower surface 5 are both smooth curved surfaces, seamlessly connected with the left side surface 1, the right side surface 2 and the rear side surface 3 in a gradual radius transition manner, and together form the outer contour of the main carrier; the main carrier is a hollow structure, shaped like a water drop with a pointed cone end, and symmetrical on both sides. The upper surface 4 and the lower surface 5 have a high degree of finish, and the surface roughness Ra (arithmetic mean deviation of the profile) of the two is less than 1.6.

[0041] Three flange interfaces are arranged in the middle of the upper surface 4: flange interface 1 6, flange interface 2 7 and flange interface 3 8, which are respectively used to install components for RCS test above S band. The edges of the three flange interfaces are provided with depressions, and the depressions of the three flange interfaces are lower than the upper surface 4 of the main carrier. Several countersunk holes are arranged in the depressions for installing the components to be tested. After installation, the mounting seat of the components to be tested is installed behind the flange interface, and the upper surface of the mounting seat is flush with the upper surface 4. The components to be tested are installed at the corresponding flange interfaces by countersunk screws; after installation, the head direction of the components to be tested is consistent with the forward direction of the main carrier (i.e. the direction of the pointed cone end), the bottom edge of the components to be tested (i.e. the upper surface of the mounting seat of the components to be tested) is flush with the upper surface 4, and the gap between the bottom of the components to be tested and the upper surface 4 is pasted with aluminum foil.

[0042] In practical applications, all flange interface recesses are set to be lower than the upper surface 4 in order to effectively cover the edge and embedded structure of the tested component. After the tested component is installed, its bottom upper surface is flush with the upper surface 4 of the main carrier. At the same time, the main carrier is a hollow structure, which is convenient for accommodating the part of the test component that needs to be hidden and can reduce the weight of the main carrier.

[0043] The distance between the front end point and the rear end point of the main carrier is 2000 mm, which meets the evaluation and measurement requirements of general low-scattering components and is also convenient for testing.

[0044] The distance between the left and right sides of the main carrier is 600 mm, which meets the evaluation and measurement requirements of general low-scattering components and is also convenient for testing.

[0045] The pointed cone end of the outer contour of the main carrier is chamfered, and the radius of the chamfer is less than 1 mm. If the chamfer radius of the pointed cone end is too large, it will cause mirror reflection of the main carrier head.

[0046] The angle between the two front side edges of the upper surface 4 is 54°, which is beneficial to transferring the scattering of the main carrier head within the range of ±45° and reducing the RCS of the main carrier head within the test angular range according to the electromagnetic scattering theory.

[0047] like Figure 4 As shown, the absorbing sleeve is composed of a low-frequency left front absorbing sleeve 12, a low-frequency left rear absorbing sleeve 13, a low-frequency right front absorbing sleeve 14 and a low-frequency right rear absorbing sleeve 15. The absorbing sleeve is a hollow structure, shaped like a water drop with a tip, symmetrical on both sides, and its surface is a smooth curved surface. The inner side is in contact with the outer side of the main carrier, and an opening is provided in the middle of the upper surface of the absorbing sleeve to avoid the three flange interfaces on the main carrier; the absorbing sleeve is composed of a low-frequency left front absorbing sleeve 12, a low-frequency left rear absorbing sleeve 13, a low-frequency right front absorbing sleeve 14 and a low-frequency right rear absorbing sleeve 15, which are respectively assembled on the main carrier and pasted and spliced ​​together for low-frequency RCS testing below S. When the absorbing sleeve is tested below the S band, it needs to be assembled on the main carrier, and the inner surface of the absorbing sleeve is in contact with the outer side of the main carrier.

[0048] like Figure 5 As shown, the supporting shaped foam 10 is a truncated cone structure, which is placed under the main carrier or the main carrier with an absorbing sleeve, and is used to place the tested component in a test posture during darkroom testing. The elevation angle adjustment foam 11 is a truncated cone structure with a certain inclination angle, which is placed under the supporting shaped foam 10 and is used to adjust the pitch angle.

[0049] like Figure 6 As shown, the test calibration block 9 is matched with the low-scattering joint carrier and is placed at the set position of the central axis in the front part of the upper surface 4 when in use. The top of the block is a plane and is used in conjunction with a level ruler placed thereon to test the actual placement posture angle.

[0050] When the electromagnetic wave is incident on the target carrier at grazing incidence, the mirror reflection does not play a major role. Secondary scattering sources such as edge diffraction and creeping wave will make a major contribution to the target RCS. Once the electric field has a component along the target surface or edge direction, the surface current induced by the electric field will flow along the target surface to form a traveling wave current, generating surface traveling wave scattering. When the carrier is used to test and evaluate the target stealth component, when the electromagnetic wave is incident on the edge of the carrier, edge diffraction will occur; when the wave is incident perpendicular to the edge, the diffraction is stronger, and when it is incident at grazing incidence, the diffraction is weaker; similar to the mirror reflection reduction method, adjusting the vertical direction of the edge to outside the test angle range (low scattering is required in this angle range) can effectively reduce the edge diffraction of the target carrier; therefore, the key to the carrier design is to perform a gradient radius smooth transition process on the adjacent surfaces of the target carrier to reduce edge diffraction and surface wave scattering.

[0051] For low frequency bands below the S band, low scattering technology achieved by shape is only effective for radar waves with shorter wavelengths. As the frequency decreases and the wavelength increases, the effect of low scattering design achieved by shape will gradually weaken, creeping wave scattering and resonance effects will increase, and slight shape changes will have almost no effect on target scattering. This means that for low-frequency radars, low RCS characteristics cannot be obtained within a wider frequency band by relying on shape to achieve low scattering technology. By using absorbing sleeves to attenuate electromagnetic waves, edge scattering and creeping wave diffraction at the edge connection of the target carrier are suppressed, and low scattering effects can be achieved in horizontal and vertical polarization states, covering the requirements of low RCS carriers in high and low frequency bands. The design of the low-scattering combined carrier described in the present invention analyzes the reduction measures at various angles within the carrier broadband.

[0052] The low-scattering joint carrier of the present invention has a good surface current guiding effect. When the component is tested for RCS in the head direction, side direction, and rear direction, it will produce low scattering, which will not affect the accuracy of the test results. In actual measurements, the RCS of the low-scattering joint carrier is more than 10 to 20 dBsm lower than the RCS of the component. In addition, the shape and hollow structure of the low-scattering joint carrier also make it have a small volume and weight.

[0053] During installation, the components to be tested are installed on flange interface 1 6, flange interface 2 7 and flange interface 3 8 respectively by countersunk screws. After installation, the bottom edge of the component to be tested is flush with the upper surface 4, and the gap between the bottom edge of the component to be tested and the upper surface 4 and the screws are pasted with aluminum foil or conductive adhesive. In this way, the edge and embedded structure of the component to be tested are shielded by the carrier, and the RCS of multiple components can be accurately measured.

[0054] When testing below the S-band, the low-frequency left front absorbing sleeve 12, the low-frequency left rear absorbing sleeve 13, the low-frequency right front absorbing sleeve 14, and the low-frequency right rear absorbing sleeve 15 are respectively assembled on the two sides of the carrier and bonded with American paper tape so that the outer edge of the carrier is buried in the absorbing sleeve structure to suppress low-frequency traveling wave scattering, so that the RCS of the low-scattering combined carrier below the S-band can be accurately measured.

[0055] During the test, the support shaping foam 10 and the elevation adjustment foam 11 cooperate to adjust the test angle, the test calibration block 9 is placed at a set position in front of the upper surface 4, and the actual posture angle is tested with a level ruler.

[0056] In this embodiment, the low-scattering combined carrier is a metal carrier, which is composed of an internal metal frame covered with a metal skin, and can be manufactured by casting, CNC machining, etc. Among them, the internal metal frame structure has high overall strength and deformation resistance, and the outer surface of the metal skin has high smoothness. The overall weight of the low-scattering combined carrier does not exceed 42kg, which is convenient for movement.

[0057] In summary, the low-scattering joint carrier and the tested component adopt an integrated structural design, the two are smoothly and tightly combined, and the gaps and screws are sealed with aluminum foil or conductive glue to eliminate the scattering interference of the edge and inner cavity structure of the component, so as to achieve the effect of simulating the actual state of the component when installed, and obtain RCS data that is relatively close to the installed state of the stealth component. The shape of the low-scattering joint carrier is suitable for the test and evaluation of stealth components that meet the size requirements, such as light windows. It can not only obtain the stealth performance of a single component separately, but also obtain the stealth performance of multiple components at the same time, reducing costs and increasing efficiency. It has been verified that within the range of ±45° in the head direction, the forward RCS±45° average of the low-scattering joint carrier is 10 to 20 dBsm lower than the RCS of the component, which can realize accurate testing of the RCS of low-scattering targets. The low-scattering joint carrier is suitable for RCS testing and evaluation of various stealth target components that meet the size requirements.

[0058] The above-described embodiments merely express the implementation methods of the present invention, but they cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A low-scattering joint carrier that takes into account RCS testing of multiple finished products, characterized in that: The low-scattering combined carrier comprises: a main carrier, a test calibration block (9), a supporting shaping foam (10), an elevation adjustment foam (11) and a wave absorbing sleeve; The main carrier comprises a left side surface (1), a right side surface (2), a rear side surface (3), an upper surface (4), a lower surface (5), a flange interface 1 (6), a flange interface 2 (7), and a flange interface 3 (8); the upper surface (4) and the lower surface (5) are both smooth curved surfaces, seamlessly connected with the left side surface (1), the right side surface (2), and the rear side surface (3) in a gradient radius transition manner, and together form the outer contour of the main carrier; the main carrier is a hollow structure, and is in the shape of a water drop with a pointed cone end, and is bilaterally symmetrical; The upper surface (4) is provided with three flange interfaces in the middle: flange interface 1 (6), flange interface 2 (7) and flange interface 3 (8), which are respectively used to install the components to be tested by RCS. The edges of the three flange interfaces are all provided with depressions, which are lower than the upper surface (4) and are used to install the components to be tested. After installation, the bottom edge of the components to be tested is flush with the upper surface (4), and the head direction of the components to be tested is consistent with the direction of the pointed cone end of the main carrier. The absorbing sleeve is composed of a low-frequency left front absorbing sleeve (12), a low-frequency left rear absorbing sleeve (13), a low-frequency right front absorbing sleeve (14) and a low-frequency right rear absorbing sleeve (15). The absorbing sleeve is a hollow structure, shaped like a water drop with a sharp tip, bilaterally symmetrical, and has a smooth curved surface. The inner side surface is in contact with the outer side surface of the main carrier, and an opening is arranged in the middle of the upper surface of the absorbing sleeve to avoid three flange interfaces on the main carrier. During installation, the low-frequency left front absorbing sleeve (12), the low-frequency left rear absorbing sleeve (13), the low-frequency right front absorbing sleeve (14) and the low-frequency right rear absorbing sleeve (15) are respectively assembled on the main carrier and pasted and spliced ​​together for low-frequency RCS testing below the S band. The supporting shaped foam (10) is a truncated cone structure, which is placed under the main carrier or the main carrier with an absorbing sleeve, and is used for testing the placement of the posture; the elevation adjustment foam (11) is a truncated cone structure with a certain inclination angle, which is placed under the supporting shaped foam (10), and is used for adjusting the pitch angle; The test calibration block (9) matches the main carrier and is placed at a set position of the central axis of the front part of the upper surface (4) of the main carrier when in use. Its top is a plane and is used in conjunction with a level ruler placed thereon to test the actual placement posture angle.

2. A low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: A plurality of countersunk holes are arranged at the concave portion of the flange interface edge for mounting the measured component by countersunk screws.

3. A low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: The pointed cone end of the outer contour of the main carrier is chamfered, and the radius of the chamfer is less than 1 mm.

4. The low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: The front inner angle of the main carrier, that is, the angle between the two side edges of the upper surface (4) close to the pointed cone end is 54±5°.

5. The low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: The surface roughness Ra of the upper surface (4) and the lower surface (5) is less than 1.

6.

6. The low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: The low-scattering combined carrier has a length of 2000 mm to 2100 mm, a width of 600 mm to 700 mm, and a height of 220 mm.

7. The low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: The low-scattering joint carrier can perform joint testing on three components under test simultaneously.

8. The low-scattering joint carrier for taking into account RCS tests of multiple finished products according to claim 1, characterized in that: The low-scattering combined carrier is capable of performing RCS testing of a component alone through a sealing process.

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