Radiation scattering integrated low rcs metasurface antenna
Patent Information
- Application Number
- CN202522060633.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-25
- Publication Date
- 2026-08-28
- Estimated Expiration
- 2035-09-25
AI Technical Summary
[0005]但是，上述超表面天线均是通过加载的方式实现RCS的缩减，存在增加剖面高度、提升模型复杂度的缺点，且未能实现工作频带内的主极化RCS缩减，而带内主极化RCS占据了天线总RCS的很大一部分
本实用新型所提供的辐射散射一体化的低RCS超表面天线在同一口径面下共同设计超表面散射单元和天线辐射贴片，实现了良好的辐射性能和散射调控性能；本实用新型剖面低，结构紧凑，易于实现，具有很强的工程实践意义；通过调节变容二极管的电容值，调控超表面天线单元作为散射体时的反射相位。通过合理的阵列排布，能够进一步缩减天线阵列端接匹配负载时的带内主极化RCS。
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Figure CN224696966U_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of microwave antenna technology, specifically relating to a low RCS metasurface antenna that integrates radiation and scattering. Background Technology
[0002] Radar stealth technology is an important technique for reducing the probability of being detected by radar. Radar cross section (RCS) is a measure of a target's ability to scatter electromagnetic waves in the direction a radar receives it; it is characterized by the ratio of the power scattered by the target in the radar receiving direction to the power density incident on the target. Reducing the target's RCS can decrease the power scattered by the target, thus lowering the probability of the target being detected.
[0003] Antennas differ from ordinary structures in that, in addition to the scattering field caused by structural factors, they also possess a secondary radiation field due to port mismatch, namely the antenna mode scattering field. Furthermore, as a crucial component for radiating and receiving electromagnetic waves, antennas need to reduce their RCS value while ensuring their own radiation performance.
[0004] In recent years, electromagnetic metasurface technology has developed rapidly. It possesses electromagnetic properties not found in naturally occurring materials, enabling flexible manipulation of electromagnetic waves. Introducing metasurfaces into the design of low-RCS antennas can fully utilize their electromagnetic manipulation capabilities while maintaining good radiation and scattering performance. Y. Zheng et al. designed a low-RCS metasurface antenna based on artificial magnetic conductors. This antenna was loaded with artificial magnetic conductor metasurface units with different reflection phases, achieving RCS reduction. S. Xiao et al. proposed a low-RCS metasurface antenna with a loaded polarization rotating surface. By loading a mirror-symmetric polarization rotating metasurface on a floor, they achieved out-of-band RCS reduction in the 6-18 GHz dual-polarization range using the principle of scattered field cancellation.
[0005] However, the above metasurface antennas all achieve RCS reduction by loading, which has the disadvantages of increasing the profile height and increasing the model complexity. Furthermore, they fail to achieve RCS reduction of the main polarization within the operating frequency band, while the main polarization RCS within the band accounts for a large part of the antenna's total RCS. Summary of the Invention
[0006] To address the aforementioned issues, this invention proposes a low-RCS metasurface antenna based on an integrated radiation and scattering design. By co-designing the metasurface scattering unit and the radiating patch, it achieves excellent radiation and scattering control performance on the same aperture surface. It features a lower profile and a more compact structure, making it suitable for further reduction of the in-band main polarization RCS when the antenna array is terminated with a matched load.
[0007] To achieve the above objectives, this utility model provides the following technical solution: a low RCS metasurface antenna integrating radiation and scattering, comprising, from top to bottom, an integrated radiation and scattering metal structure, a varactor diode loaded on the integrated radiation and scattering metal structure, a first dielectric substrate, a metal ground plane, a second dielectric substrate, and a microstrip transmission line. The integrated radiation scattering metal structure, the metal ground plane, and the microstrip transmission line work together to achieve radiation. The integrated radiation-scattering metal structure and the varactor diode work together to achieve scattering control.
[0008] The low RCS metasurface antenna integrating radiation and scattering provided by this utility model also has the following technical features: the integrated radiation and scattering metal structure includes concentric square metal patches and square annular metal patches disposed around the square metal patches.
[0009] The low RCS metasurface antenna with integrated radiation and scattering provided by this utility model also has the following technical feature: the square metal patch has a side length of 8-9mm.
[0010] The low RCS metasurface antenna integrating radiation and scattering provided by this utility model also has the following technical features: the outer side length of the square annular metal patch is 13-15mm and the width is 0.6-1mm.
[0011] The low RCS metasurface antenna integrating radiation and scattering provided by this utility model also has the following technical features: the relative permittivity of the first dielectric substrate is 2.6-2.7, and the loss tangent is 0.001-0.002.
[0012] The low RCS metasurface antenna integrating radiation and scattering provided by this utility model also has the following technical features: the metal ground plane has a dumbbell-shaped slot, and the metal ground plane and the microstrip transmission line constitute the feeding structure when the metasurface antenna acts as a radiator.
[0013] The low RCS metasurface antenna integrating radiation and scattering provided by this utility model also has the following technical features: the relative permittivity of the second dielectric substrate is 3.4-3.6, and the loss tangent is 0.0015-0.0025.
[0014] Beneficial effects This invention provides a low RCS metasurface antenna integrating radiation and scattering, where the metasurface scattering element and antenna radiating patch are designed together under the same aperture plane, achieving excellent radiation and scattering control performance. This invention features a low profile, compact structure, and ease of implementation, making it highly significant for engineering practice. The reflection phase of the metasurface antenna element as a scatterer can be controlled by adjusting the capacitance value of the varactor diode. Through reasonable array arrangement, the in-band main polarization RCS can be further reduced when the antenna array is terminated with a matched load. Attached Figure Description
[0015] To more clearly illustrate the technical solutions of the embodiments of this disclosure, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0016] Figure 1 A three-dimensional structural schematic diagram of the low RCS metasurface antenna unit integrating radiation and scattering provided in an embodiment of this utility model; Figure 2 This is a side view of the low RCS metasurface antenna element with integrated radiation and scattering as mentioned in the embodiment of this utility model; Figure 3 This is a schematic diagram of the top patch structure of a low RCS metasurface antenna unit that integrates radiation and scattering according to this utility model.
[0017] Figure 4 This is a schematic diagram of the metal ground plane structure of a low RCS metasurface antenna element that integrates radiation and scattering according to this utility model.
[0018] Figure 5 This is a schematic diagram of the underlying microstrip transmission line structure of a low RCS metasurface antenna unit that integrates radiation and scattering according to this utility model.
[0019] Figure 6 This invention relates to a low RCS metasurface antenna element that integrates radiation and scattering, when used as a radiator, and presents its port reflection coefficient curve.
[0020] Figure 7 This invention relates to a low RCS metasurface antenna element that integrates radiation and scattering, which serves as a radiator. The radiation patterns of the E-plane and H-plane at 6 GHz are shown.
[0021] Figure 8 This invention relates to a low RCS metasurface antenna element that integrates radiation and scattering, which serves as a scatterer. The reflection amplitude curves are shown when the varactor tube has different capacitance values.
[0022] Figure 9 This invention relates to a low RCS metasurface antenna element that integrates radiation and scattering, which is used as a scatterer. The reflection phase curves are shown when the varactor tube has different capacitance values.
[0023] Figure 10 This is a comparison of the RCS curves of a low RCS metasurface antenna array integrating radiation and scattering, and a contrast array, according to this utility model. Wherein, 1: metal structure; 2: varactor diode; 3: metal ground plane; 4: microstrip transmission line; 5: first dielectric substrate; 6: second dielectric substrate. Detailed Implementation
[0024] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be noted that these embodiments are not intended to limit the present invention. Equivalent transformations or substitutions in function, method, or structure made by those skilled in the art based on these embodiments are all within the protection scope of the present invention.
[0025] In the description of the embodiments of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limiting this utility model.
[0026] Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.
[0027] The terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.
[0028] like Figure 1As shown, this embodiment of the present invention provides a low RCS metasurface antenna integrating radiation and scattering, comprising, from top to bottom, an integrated radiation and scattering metal structure 1, a varactor diode 2 loaded on the integrated radiation and scattering metal structure 1, a first dielectric substrate 5, a metal ground plane 3, a second dielectric substrate 6, and a microstrip transmission line 4. The integrated radiation scattering metal structure 1, the metal ground plane 3, and the microstrip transmission line 4 work together to achieve radiation. The integrated radiation and scattering metal structure 1 and the varactor diode 2 work together to achieve scattering control.
[0029] In some embodiments, the radiation scattering integrated metal structure 1 includes concentrically arranged square metal patches and square annular metal patches disposed around the square metal patches.
[0030] In some embodiments, the square metal patch has a side length of 8-9 mm.
[0031] In some embodiments, the outer side length of the square annular metal patch is 13-15mm and the width is 0.6-1mm.
[0032] In some embodiments, the relative permittivity of the first dielectric substrate 5 is 2.6-2.7, and the loss tangent is 0.001-0.002.
[0033] In some embodiments, the metal ground plane 3 has a dumbbell-shaped slot, and the metal ground plane and the microstrip transmission line constitute the feeding structure when the metasurface antenna is used as a radiator.
[0034] In the above embodiments, the dumbbell-shaped slit, compared to the rectangular slit, introduces an additional resonant path by extending an additional dumbbell-shaped structure at the end, which can excite multimode resonance and thus broaden the operating bandwidth.
[0035] In some embodiments, the relative permittivity of the second dielectric substrate 6 is 3.4-3.6, and the loss tangent is 0.0015-0.0025.
[0036] In some embodiments, such as Figure 2-10 As shown, Figure 2 A side view of the metasurface antenna element is given. From top to bottom, it consists of an integrated radiation and scattering metal structure 1, a varactor diode 2 loaded on the metal patch 1, a dielectric substrate 5, a metal ground plane 3, a dielectric substrate 6, and a microstrip transmission line 4. The dielectric substrate 5 has a thickness t1 = 3.4 mm, a relative permittivity of 2.65, and a loss tangent of 0.0015; the dielectric substrate 6 has a thickness t2 = 0.508 mm, a relative permittivity of 3.5, and a loss tangent of 0.002.
[0037] like Figure 3 As shown, the radiation scattering integrated metal structure 1 includes a square metal patch and an outer metal ring structure. The square metal patch has a side length l2 = 8.8 mm, and the outer metal ring structure has a side length l1 = 14 mm and a width w1 = 0.8 mm. Two varactor diodes are symmetrically loaded on the metal ring structure.
[0038] like Figure 4 As shown, the metal ground plane 3 has a dumbbell-shaped gap with a length l4 = 9.4 mm and a width w3 = 1.6 mm.
[0039] The parameters of the embodiments of the present invention are shown in the following table: Table 1. Structural parameters of metasurface antennas (unit: mm)
[0040] Full-wave simulation was performed on the metasurface antenna element to analyze its performance as a radiator and scatterer. As a radiator, the port reflection coefficient curve of the metasurface antenna element is shown below. Figure 6 As shown in the figure, the metasurface antenna element |S 11 The bandwidth of |<-10dB is 5.48-6.72GHz. Figure 7 The figures show the E-plane and H-plane radiation patterns of the metasurface antenna element at 6 GHz when it acts as a radiator. The maximum gain of the metasurface antenna element at 6 GHz is 6.22 dBi, the 3 dB beamwidth of the E-plane is 83.8°, and the 3 dB beamwidth of the H-plane is 95°. When it acts as a scatterer, the simulation settings are as follows: periodic boundaries are set around the element, and the element is terminated with a 50Ω matched load. Figure 8 and Figure 9 The reflection amplitude and phase curves of the metasurface antenna element are shown for different capacitance values of the applied varactor tube. As can be seen from the figure, when the varactor tube capacitance is set to 0.06pF and 0.08pF, the reflection amplitude of the metasurface antenna element is equal at 6.05GHz, and the reflection phase difference is 189°. In the 6.1-6.2GHz range, the reflection amplitude is approximately the same, and the reflection phase is within the range of 180°±37°, which meets the scattering cancellation condition. Equal numbers of the two types of metasurface antenna elements with varactor tube capacitance values of 0.06pF and 0.08pF are arranged to form a 4*4 array, with 50Ω matched loads connected to the array elements, and their RCS performance is simulated. Figure 10The figures show the RCS comparison curves of the proposed metasurface antenna array and the comparison array. In comparison array 1, the varactor diodes are all set to 0.06 pF, and in comparison array 2, they are all set to 0.08 pF. The comparison array and the proposed array are identical except for the capacitance values. As can be seen from the figures, the proposed array has the lowest RCS of -36 dBsm at 6.14 GHz, and its RCS is lower than that of the comparison array in the 6-6.3 GHz range. This demonstrates that the proposed metasurface antenna element can achieve control over the reflection amplitude and phase while maintaining good radiation performance. By arranging elements with similar reflection amplitudes and opposite reflection phases in an equal number in an array, the main polarization RCS can be further reduced when the array is terminated with a load.
[0041] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model. The above description is only a preferred embodiment of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.