Multiband microwave metasurface absorber

Abstract

The invention discloses a multiband microwave metasurface absorber, and relates to the technical field of microwave functional devices, the multiband microwave metasurface absorber comprises a plurality of unit structures which are periodically arranged, and each unit structure comprises a metal grounding layer, an intermediate dielectric layer and a top metal resonance structure which are arranged from bottom to top; the top metal resonant structure comprises a peripheral closed ring and a metal cross-shaped structure arranged in the center of the peripheral closed ring, and the peripheral closed ring is formed by connecting four square metal rings end to end; the size of each square metal ring and the size of the metal cross-shaped structure are configured to enable the absorber to excite at least two resonance absorption peaks with the quality factors larger than 400 in the microwave frequency band of 8 GHz to 20 GHz. The dual requirements of multi-band coverage and high-frequency selectivity are met at the same time.

Description

Technical Field

[0001] This application relates to the field of microwave functional device technology, and in particular to a multi-band microwave metasurface absorber. Background Technology

[0002] Microwave metasurface absorbers, as artificially designed two-dimensional electromagnetic structures, can efficiently absorb incident electromagnetic waves in specific frequency bands, and have wide applications in radar stealth, electromagnetic compatibility, sensing and detection, and communication systems. Their core performance indicators include absorptivity, operating bandwidth, and frequency selectivity.

[0003] In recent years, significant progress has been made in the research of metasurface absorbers. Some metamaterial absorbers have achieved high absorption at a single frequency, but their quality factor (Q value) is low, and their frequency selectivity is limited, making it difficult to distinguish closely adjacent frequency signals. Subsequently, researchers explored multi-band and tunable absorbers, such as graphene-based metasurfaces, to achieve switching of absorption modes. However, related technologies still face challenges: single-frequency absorbers cannot meet the requirements of multi-band systems; and common multi-band or broadband absorbers typically have wide resonant peaks (low Q values), resulting in poor isolation between different frequency bands and easy signal interference. This severely limits their use in applications requiring high-precision frequency resolution (such as precision spectrum sensing and multi-frequency communication channel filtering).

[0004] Therefore, developing a metasurface absorber that can cover multiple commonly used communication frequency bands and has extremely high frequency selectivity is of great practical value and an urgent technical need. Summary of the Invention

[0005] The purpose of this application is to provide a multi-band microwave metasurface absorber that achieves the excitation of multiple sharp resonant absorption peaks with high Q values ​​over a wide frequency range, thereby simultaneously meeting the dual requirements of multi-band coverage and high frequency selectivity.

[0006] To achieve the above objectives, this application provides the following solution.

[0007] This application provides a multi-band microwave metasurface absorber, comprising: multiple periodically arranged unit structures, each of which includes: a metal ground layer, an intermediate dielectric layer and a top metal resonant structure arranged from bottom to top; The top-level metal resonant structure includes: an outer closed loop and a metal cross-shaped structure disposed at the center of the outer closed loop, wherein the outer closed loop is formed by four square metal rings connected end to end; The dimensions of each of the square metal rings and the dimensions of the metal cross structure are configured such that the absorber excites at least two resonant absorption peaks with a quality factor greater than 400 in the microwave frequency band from 8 GHz to 20 GHz.

[0008] In one embodiment, the period of the unit structure is 8 mm, and the thickness of the intermediate dielectric layer is 3 mm.

[0009] In one embodiment, the side length of the outer closed loop is 7.2 mm.

[0010] In one embodiment, the width of the metal wire in the metal cross-shaped structure is 0.4 mm, the width of the metal wire on the outer edge of the square metal ring is 0.4 mm, and the width of the metal wire on the inner edge of the square metal ring is 0.5 mm.

[0011] In one embodiment, the metal ground layer and the top metal resonant structure are made of gold, and the intermediate dielectric layer is made of silicon.

[0012] In one embodiment, there is no electrical connection between the metal cross-shaped structure and the outer closed loop.

[0013] In one embodiment, the absorber excites six resonant absorption peaks in the frequency band from 8 GHz to 20 GHz.

[0014] In one embodiment, the absorption frequencies of the six resonant absorption peaks are 11.876 GHz, 14.216 GHz, 15.992 GHz, 16.58 GHz, 18.548 GHz and 19.469 GHz, respectively.

[0015] In one embodiment, at least one of the six resonant absorption peaks has a quality factor greater than 1000.

[0016] In one embodiment, the thickness of both the metal grounding layer and the top metal resonant structure is 30 μm.

[0017] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application discloses a multi-band microwave metasurface absorber, wherein the top-layer metal resonant structure in each unit structure can effectively excite at least two independent resonant absorption peaks in a wide frequency range of 8 GHz to 20 GHz, completely covering the X and Ku bands and extending to the K band; at the same time, the quality factor (Q value) of these resonant absorption peaks is greater than 400, and their frequency selectivity is improved by more than an order of magnitude compared with traditional absorbers (Q value of about 25), which can accurately distinguish adjacent frequency band signals, fundamentally solving the problem of signal crosstalk when operating in multiple frequency bands, and realizing the excitation of multiple sharp resonant absorption peaks with high Q values ​​in a wide frequency range, thereby simultaneously meeting the dual requirements of multi-band coverage and high frequency selectivity. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A structural diagram of a multi-band microwave metasurface absorber provided in an embodiment of this application; Figure 2 This is the absorption spectrum of a multi-band microwave metasurface absorber. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described 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 of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The purpose of this application is to provide a multi-band microwave metasurface absorber that aims to excite multiple sharp resonant absorption peaks with high Q values ​​over a wide frequency range, thereby simultaneously meeting the dual requirements of multi-band coverage and high frequency selectivity.

[0022] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] In one exemplary embodiment, such as Figure 1 As shown, a multi-band microwave metasurface absorber is provided, comprising: multiple unit structures arranged periodically, each unit structure including: a metal grounding layer, an intermediate dielectric layer and a top metal resonant structure arranged from bottom to top.

[0024] The top-level metal resonant structure includes an outer closed loop and a metal cross-shaped structure set at the center of the outer closed loop. The outer closed loop is composed of four square metal rings connected end to end.

[0025] The dimensions of each square metal ring and the metal cross structure are configured such that the absorber excites at least two resonant absorption peaks with a quality factor greater than 400 in the microwave frequency band from 8 GHz to 20 GHz.

[0026] Specifically, the high Q value (quality factor greater than 400) gives the multi-band microwave metasurface absorber extremely strong frequency selectivity, which can accurately distinguish adjacent frequency band signals; the multi-resonant peak design achieves complete coverage of the X and Ku bands and extends to the K band.

[0027] As an optional implementation, the period (P) of the unit structure is 8 mm and the thickness (P1) of the intermediate dielectric layer is 3 mm.

[0028] As an alternative implementation, the side length (P2) of the outer closed loop is 7.2 mm.

[0029] As an optional implementation, the width (W1) of the metal wire in the metal cross-shaped structure is 0.4 mm, the width (W2) of the metal wire on the outer edge of the square metal ring is 0.4 mm, and the width (W3) of the metal wire on the inner edge of the square metal ring is 0.5 mm.

[0030] As an alternative implementation, the metal ground layer and the top metal resonant structure are made of gold, and the intermediate dielectric layer is made of silicon.

[0031] As an alternative implementation, there is no electrical connection between the metal cross-shaped structure and the outer closed loop.

[0032] As an alternative implementation, the absorber excites six resonant absorption peaks in the frequency band from 8 GHz to 20 GHz.

[0033] As an optional implementation, the absorption frequencies of the six resonant absorption peaks are 11.876 GHz, 14.216 GHz, 15.992 GHz, 16.58 GHz, 18.548 GHz and 19.469 GHz, respectively.

[0034] As an alternative implementation, at least one of the six resonant absorption peaks has a quality factor greater than 1000.

[0035] Specifically, the Q values ​​of the six resonant absorption peaks are 403, 575, 529, 954, 1101, and 1854, respectively.

[0036] As an optional implementation, the thickness of both the metal grounding layer and the top metal resonant structure is 30 μm.

[0037] Specifically, such as Figure 2 As shown, the multi-band microwave metasurface absorber of this application has an absorption rate of over 70% at absorption frequencies of 11.876 GHz, 16.58 GHz, 18.548 GHz and 19.469 GHz.

[0038] This application's multi-band microwave metasurface absorber overcomes the performance bottleneck of traditional single-band, low-selectivity microwave metasurface absorbers. On the one hand, its design covering X / Ku / K bands aligns with the current technological trend of multi-band collaborative operation in fields such as communication and radar, reducing the size and cost of integrating multiple devices. On the other hand, the strong frequency selectivity brought by the ultra-high Q value solves the industry pain point of easy interference of multi-band signals, providing high-resolution core device support for microwave sensing, high-precision spectrum detection, and other scenarios. Furthermore, the absorber adopts a gold-silicon heterostructure, and its fabrication process is compatible with existing semiconductor processes, combining performance advantages with industrialization potential. It has significant practical value in promoting the miniaturization and high-precision development of microwave functional devices.

[0039] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0040] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the device and its core ideas. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A multi-band microwave metasurface absorber, characterized in that, The multi-band microwave metasurface absorber includes: multiple periodically arranged unit structures, each of which includes: a metal grounding layer, an intermediate dielectric layer and a top metal resonant structure arranged from bottom to top; The top-level metal resonant structure includes: an outer closed loop and a metal cross-shaped structure disposed at the center of the outer closed loop, wherein the outer closed loop is formed by four square metal rings connected end to end; The dimensions of each of the square metal rings and the dimensions of the metal cross structure are configured such that the absorber excites at least two resonant absorption peaks with a quality factor greater than 400 in the microwave frequency band from 8 GHz to 20 GHz.

2. The multi-band microwave metasurface absorber according to claim 1, characterized in that, The period of the unit structure is 8mm, and the thickness of the intermediate dielectric layer is 3mm.

3. The multi-band microwave metasurface absorber according to claim 1, characterized in that, The side length of the outer closed loop is 7.2 mm.

4. The multi-band microwave metasurface absorber according to claim 1, characterized in that, The width of the metal wire in the metal cross-shaped structure is 0.4 mm, the width of the metal wire on the outer edge of the square metal ring is 0.4 mm, and the width of the metal wire on the inner edge of the square metal ring is 0.5 mm.

5. The multi-band microwave metasurface absorber according to claim 1, characterized in that, The metal grounding layer and the top metal resonant structure are made of gold, and the intermediate dielectric layer is made of silicon.

6. The multi-band microwave metasurface absorber according to claim 1, characterized in that, There is no electrical connection between the metal cross-shaped structure and the outer closed loop.

7. The multi-band microwave metasurface absorber according to claim 1, characterized in that, The absorber excites six resonant absorption peaks in the frequency band from 8 GHz to 20 GHz.

8. The multi-band microwave metasurface absorber according to claim 7, characterized in that, The absorption frequencies of the six resonant absorption peaks are 11.876 GHz, 14.216 GHz, 15.992 GHz, 16.58 GHz, 18.548 GHz and 19.469 GHz, respectively.

9. The multi-band microwave metasurface absorber according to claim 7, characterized in that, At least one of the six resonant absorption peaks has a quality factor greater than 1000.

10. The multi-band microwave metasurface absorber according to claim 1, characterized in that, The thickness of both the metal grounding layer and the top metal resonant structure is 30 μm.

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