Miniaturized metasurface broadband wide-angle scanning circularly polarized antenna

Abstract

The invention discloses a miniaturized metasurface broadband wide-angle scanning circularly polarized antenna, and belongs to the technical field of antennas. A wide-angle scanning phased-array antenna can be formed by using the miniaturized metasurface broadband wide-angle scanning circularly polarized antenna as a unit. The miniaturized metasurface broadband wide-angle scanning circularly polarized antenna comprises three layers of dielectric plates, four metal layers and a group of metalized via holes. And by utilizing the non-linear characteristic of a metasurface dispersion curve, the first-order resonant frequency and the second-order resonant frequency are fused to realize broadband radiation. The metasurface antenna is miniaturized by increasing the propagation constant, so that the array element spacing in the array is reduced, and wide-angle scanning is realized. The invention has the characteristics of few layers, small size, large bandwidth, wide-angle scanning and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of antenna, in particular to a miniaturized metasurface wideband wide-angle scanning circularly polarized antenna. BACKGROUND

[0002] As an advanced antenna technology, phased array antenna has the advantages of flexible beam scanning, high pointing accuracy, strong multi-beam forming capability, etc., and is widely used in radar, satellite communication, mobile communication and other fields. Traditional low-profile phased array antennas mostly use microstrip patch antennas, but their narrow operating bandwidth cannot meet the wideband requirement. In recent years, metamaterial antennas have attracted much attention due to their low profile and wide bandwidth, but the size of the antenna unit is relatively large, which makes it difficult to apply in phased array antennas with large scanning angles. Current methods for miniaturizing metasurface antennas include using a stacked structure, using a high dielectric constant plate, and using a meander line technique, but these methods have the problems of complex structure and narrow bandwidth. SUMMARY

[0003] The present application relates to the technical field of antenna, in particular to a miniaturized metasurface wideband wide-angle scanning circularly polarized antenna.

[0004] The purpose of the present application is achieved by the following technical solutions: A miniaturized metasurface wideband wide-angle scanning circularly polarized antenna, comprising a plurality of antenna units arranged in an array, each antenna unit comprising three layers of dielectric plates stacked in order, namely an upper dielectric plate (1), a middle dielectric plate (2), and a lower dielectric plate (3). The upper surface of the upper dielectric plate (1) is provided with a metasurface patch (4), and the metasurface patch is provided with four and arranged in a 2x2 array. The upper surface of the middle dielectric plate (2) is provided with a first metal ground plate (5); the center of the first metal ground plate (5) is provided with a cross-shaped slot (8). The upper surface of the lower dielectric plate (3) is provided with an omega-shaped strip line (6), and the lower surface is provided with a second metal ground plate (7). The first metal ground plate (5) and the second metal ground plate (7) are connected by a metallized via (9); the metallized via (9) is provided with a plurality of metallized vias (9) arranged in an annular region, and the omega-shaped strip line (6) is located in the annular region.

[0005] Further, the shape of the metasurface patch is rectangular, circular, triangular, or other regular or irregular shape.

[0006] Further, the metasurface patch is a single-layer patch.

[0007] Further, the first metal floor is etched with a cross-shaped slot.

[0008] Further, the cross-shaped slot is composed of two vertically intersecting linear slots.

[0009] Further, the omega-shaped stripline is an axisymmetric structure, which includes a circular ring segment stripline and two strip lines; the circular ring segment stripline has an opening, and the two strip lines are connected to the two ends of the circular ring segment stripline and are perpendicular to each other and outward.

[0010] Further, the spacing between adjacent metallized vias satisfies the following formula:

[0011] wherein c represents the propagation speed in free space of electromagnetic waves, f0 represents the working center frequency, w represents the spacing of metallized vias, and D represents the diameter of the metallized via.

[0012] Further, the four antenna units are an array element, and the four antenna units in the same array element are arranged in a 2x2 rectangular array, and the openings of the omega-shaped striplines of the four antenna units are all inward.

[0013] Compared with the prior art, the present application adopts a small-sized single-layer metasurface patch combined with a cross-shaped slot coupling design, and the advantages include: (1) The metasurface antenna is miniaturized, and the antenna size can be reduced to within half a wavelength required for wide-angle scanning of a phased array; (2) Compared with the laminated miniaturization method, the number of antenna layers is not increased, the structure is simple, and the processing cost is low; compared with the meandering miniaturization method, no inductive component is introduced, and the antenna has a wider working bandwidth; (3) The cross-shaped coupling slot cooperates with the omega-shaped stripline to realize wideband dual-circular polarization radiation.

[0014] The small-sized metasurface wideband wide-angle scanning circularly polarized antenna is used as a unit to form a subarray through 2x2 rotating feeding, and the two-dimensional expansion of the subarray can be expanded to a wide-angle scanning phased array antenna of any scale. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is an exploded view of the small-sized metasurface wideband wide-angle scanning circularly polarized antenna of the present application.

[0016] Figure 2 is a top view of the small-sized metasurface wideband wide-angle scanning circularly polarized antenna of the present application.

[0017] Figure 3is a dispersion simulation schematic diagram of the miniaturized metasurface wideband wide-angle scanning circularly polarized antenna of the application.

[0018] Figure 4 is a dispersion simulation result of the miniaturized metasurface wideband wide-angle scanning circularly polarized antenna of the application.

[0019] Figure 5 is a working bandwidth simulation result of the miniaturized metasurface wideband wide-angle scanning circularly polarized antenna of the application.

[0020] Figure 6 is a directional diagram simulation result of the miniaturized metasurface wideband wide-angle scanning circularly polarized antenna of the application.

[0021] Figure 7 is a top view of the miniaturized metasurface wideband wide-angle scanning circularly polarized antenna 2x2 array of the application.

[0022] Figure 8 is a top view of the miniaturized metasurface wideband wide-angle scanning circularly polarized antenna 8x8 array of the application. DETAILED DESCRIPTION

[0023] The technical solutions of the application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0024] As shown in Figures 1 to 8 , the application provides a miniaturized metasurface wideband wide-angle scanning circularly polarized antenna. The antenna adopts a laminated multi-layer dielectric plate structure to realize low profile and miniaturized design, and is suitable for a wideband wide-angle scanning circularly polarized phased array system.

[0025] The antenna unit mainly includes three layers of dielectric plates, four layers of metal layers, and a group of metallized vias. The three layers of dielectric plates are sequentially arranged from top to bottom as follows: The first dielectric plate (1): located at the uppermost layer, used for carrying the metasurface radiation patch; The second dielectric plate (2): located at the middle layer, with a first metal ground plate arranged on the top surface; The third dielectric plate (3): located at the lowermost layer, with an Ω-shaped strip line arranged on the top surface and a second metal ground plate arranged on the bottom surface.

[0026] The three layers of dielectric plates can adopt conventional PCB materials (such as TSM-DS3, with a dielectric constant of about 2.94), or can be realized by LTCC, HTCC, etc. to meet different frequency band and integration requirements.

[0027] Super surface patch (4): etched on the upper surface of the first dielectric plate (1), composed of four rectangular patches of the same size arranged in a 2 × 2 array. The 2 × 2 super surface structure has a higher propagation constant than the traditional multi-cell super surface (such as N × N, N ≥ 3) of the same size, which is beneficial to the frequency improvement and size reduction of the antenna, and realizes miniaturization.

[0028] First metal floor (5): etched on the upper surface of the second dielectric plate (2), as a coupling ground layer. The center is etched with a cross-shaped coupling slot (8), which is composed of two equal-length and equal-width one-dimensional slots intersecting with each other, used to realize circular polarization excitation and wideband coupling.

[0029] Ω type strip line (6): etched on the upper surface of the third dielectric plate (3), which is an axisymmetric structure, including an open circular ring strip line and two vertical strips respectively connecting the two ends of the circular ring and extending outward. The structure is used to realize wideband dual circular polarization feed.

[0030] Second metal floor (7): etched on the lower surface of the third dielectric plate (3), which together with the first metal floor (5) forms a shielding cavity to suppress surface waves and parasitic radiation.

[0031] A number of metalized vias (9) are arranged between the first metal floor (5) and the second metal floor (7), which are arranged in a ring array around the area where the Ω type strip line (6) is located. The diameter D and the spacing w of the via need to satisfy the following relationship:

[0032] Where c represents the propagation speed in free space of electromagnetic wave, f0 represents the working center frequency, w represents the spacing of the metalized via, and D represents the diameter of the metalized via.

[0033] Taking the center frequency of about 15 GHz as an example, using PCB process, the specific size of the antenna unit is as follows, the overall unit size: 7 mm × 7 mm × 2.4 mm. The thickness of the first dielectric plate: 1.5 mm. The thickness of the second dielectric plate: 0.75 mm. The thickness of the third dielectric plate: 0.25 mm Super surface patch size: single patch 3.2 mm × 3.2 mm, patch spacing 0.2 mm Cross-shaped slot width: 0.25 mm, length: 3 mm Ω type strip line width: 0.15 mm, middle circular ring radius: 1 mm Metalized via diameter: 0.2 mm, via spacing: 0.7 mm When the antenna works, the signal is excited by the Ω-shaped strip line (6), coupled to the upper-layer metasurface patch (4) through the cross-shaped slot (8), and the circularly polarized radiation is excited. The 2×2 metasurface patch array and the metalized via hole ring jointly regulate the electromagnetic wave propagation characteristics, realizing the performance of wideband, low profile and high scanning angle. Four antenna units can form a 2×2 rotating feed antenna array, which can further expand to form a wide-angle scanning phased array of any size.

Claims

1. A miniaturized metasurface wideband wide-angle scanning circularly polarized antenna comprising a plurality of antenna elements arranged in an array, characterized in that, Each antenna unit comprises three layers of dielectric plates stacked in sequence, namely an upper dielectric plate (1), a middle dielectric plate (2) and a lower dielectric plate (3); The upper surface of the upper dielectric plate (1) is provided with four super surface patches (4) arranged in a 2x2 array; The upper surface of the middle dielectric plate (2) is provided with a first metal ground plate (5); the center of the first metal ground plate (5) is provided with a cross-shaped slot (8); The upper surface of the lower dielectric plate (3) is provided with an omega-shaped strip line (6), and the lower surface is provided with a second metal ground plate (7); The first metal ground plate (5) and the second metal ground plate (7) are connected by a plurality of metallized vias (9); the plurality of metallized vias (9) form an annular region in an array, and the omega-shaped strip line (6) is located in the annular region.

2. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The shape of the super surface patch is rectangular, circular, triangular or other regular or irregular shape.

3. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The super surface patch is a single-layer patch.

4. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The first metal ground plate is etched with a cross-shaped slot.

5. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The cross-shaped slot is composed of two perpendicular one-shaped slots.

6. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The omega-shaped strip line is an axisymmetric structure, which includes a circular ring segment strip line and two strip lines; the circular ring segment strip line has an opening, and the two strip lines are connected to both ends of the circular ring segment strip line and are perpendicular to each other and outward.

7. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The distance between adjacent metallized vias satisfies the following formula: ； Wherein, c represents the propagation speed in the free space of electromagnetic wave, f0 represents the working center frequency, w represents the distance between metallized vias, and D represents the diameter of the metallized via.

8. The miniaturized metasurface wideband wide-angle scanning circularly polarized antenna according to claim 1, wherein, The four antenna units are an array element, and the four antenna units of the same array element are arranged in a 2x2 rectangular array, and the openings of the omega-shaped strip lines of the four antenna units are all inward.

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