Ultra-wideband dual-polarized phased-array antenna loaded with metasurface structure

Abstract

An ultra-wideband dual-polarization phased-array antenna loaded with a metasurface structure is characterized by comprising a plurality of antenna units, and each antenna unit extends along an X polarization direction and a Y polarization direction to form orthogonally placed dipole antenna units and form a planar array of any size. Each antenna unit sequentially comprises a metal floor, a radiation metal arm and a metasurface structure from bottom to top, and the radiation metal arm is divided into a grounding metal arm and a feed metal arm.

Description

Technical Field

[0001] The present invention belongs to the technical field of phased array antennas, and in particular relates to a metasurface structure and an ultra-wideband dual-polarization technology. Background Art

[0002] Phased array antennas are integrated antennas capable of high-speed scanning and multifunctional operation. They use an array antenna as their basic architecture, combined with phase shifters to achieve beam scanning within a specific airspace. Compared to mechanically scanned antennas, phased array antennas offer advantages such as fast response, convenient beamforming, wide scanning range, high positioning accuracy, and the ability to simultaneously track and process multiple targets. They are widely used in systems such as multi-function military radars, airborne surveillance radars, spaceborne radars, synthetic aperture radars, radio astronomy, and modern land mobile communications.

[0003] With the development of multifunctional apertures and the increasing number of sensing and communication systems on system platforms, there is an increasing need to integrate multiple systems into a single broadband aperture. Because these systems may operate on separate broadband frequency channels, these apertures often require the use of phased array antennas with ultra-wideband characteristics, which has become a research focus and hot topic.

[0004] All-metal phased array antennas, capable of operating in extreme environments, are a hot research topic. Compared to printed-on dielectric substrates, these antennas offer greater structural strength, higher machining precision, and reduced dielectric loss.

[0005] In summary, the all-metal ultra-wideband phased array antenna has a good development prospect. The present invention is proposed specifically for the all-metal ultra-wideband antenna technology. Summary of the Invention

[0006] In order to solve the above problems, an ultra-wideband dual-polarization phased array antenna loaded with a metasurface structure is adopted, which has an ultra-wide operating bandwidth of 9:1 and a wide beam scanning range of ±45°.

[0007] The antenna consists of several antenna units, which extend along the X-polarization direction and the Y-polarization direction respectively. The dipole antenna units are placed orthogonally to achieve dual-polarization function and form a planar array of any size.

[0008] The antenna unit includes a metal floor at the bottom layer, a radiating metal arm in the middle layer, a metasurface structure at the top layer, and an SMP ball head connector. The radiating metal arm is divided into a grounding metal arm and a feeding metal arm. The upper surface of the metasurface structure is printed with a circuit pattern.

[0009] The SMP ball connector on the metal floor is electrically connected to the feed metal arm through an elastic ball head, reducing the welding process and improving assembly consistency. No additional feed balun structure is required. The coaxial core on the metal floor feeds current to the feed metal arm, and radiates energy into free space through four radiating metal arms.

[0010] There are several elliptical holes on the periphery of the radiating metal arm to adjust the impedance matching of the antenna within the ultra-wideband operating bandwidth.

[0011] The metasurface structure is made of polyimide, with an air gap between it and the radiating metal arms, and is supported and fixed with foam.

[0012] Circuit patterns are printed on the metasurface structure to change the equivalent dielectric constant of the polyimide film, adjust the low-frequency impedance matching of the antenna when scanning at a large angle, improve the voltage standing wave ratio, and achieve a low-profile antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is a schematic diagram of the antenna array.

[0014] Figure 2 It is a three-dimensional diagram of the antenna unit.

[0015] Figure 3 It is a side view of the antenna unit.

[0016] Figure 4 It is a top view of the antenna unit.

[0017] Figure 5 This is a simulation diagram of vertical standing waves.

[0018] Figure 6 This is a simulation diagram of horizontal standing waves.

[0019] Figure 7 is the unit pattern.

[0020] Figure 8 is the vertical plane pattern.

[0021] Figure 9 is the horizontal plane pattern. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is described in detail below with reference to the accompanying drawings.

[0023] The antenna array size is 9×9 antenna units, and the 9 antenna units are along x Directionally arranged, the unit spacing is 10mm, and the 9 antenna units are arranged along y Directional arrangement, unit spacing is 10mm, the total height of the antenna unit is 14mm, such as Figure 1 shown.

[0024] The lower metal floor 103 of the antenna unit is a 6mm aluminum plate, which serves as the reflective floor of the antenna unit and fixes the SMP ball connector. The coaxial cores 104 and 105 conduct the current to the feed metal arms 107 and 109. Figure 2 As shown, equal-amplitude reverse currents are returned from the grounded metal arms 106 and 108, radiating energy into free space, thereby achieving 2-18 GHz ultra-wideband impedance matching.

[0025] The upper part of the radiating metal arm has four standard elliptical grooves with a short diameter of 1.15 mm and long diameters of 4.03 mm, 1.76 mm, 1.5 mm, and 1.15 mm from top to bottom, respectively. The ratios of the long and short diameters are 3.5:1, 1.5:1, 1.3:1, and 1:1. Figure 3 As shown, the capacitive coupling between the antennas is increased, the reactance component caused by the metal floor 103 is reduced, and the low-frequency bandwidth of the antenna is increased.

[0026] The feeding metal arms 107, 109 and the grounding metal pillars 106, 108 are asymmetric structures. Figure 4 As shown, the structural freedom of the antenna unit is increased, the impedance matching of the antenna within the entire working bandwidth is improved, and the width of the gap between the metal arms is 0.35 mm.

[0027] The upper surface of the metasurface structure 101 is printed with a pattern 102 with a thickness of 0.05 mm, which adjusts the low-frequency impedance matching of the antenna when scanning at a large angle and improves the voltage standing wave ratio. The relative dielectric constant of the polyimide 101 is 3.5, the thickness is 0.05 mm, and there is a 1 mm air gap between it and the radiating metal arm.

[0028] The simulation results of the vertical plane active voltage standing wave ratio changing with frequency are as follows Figure 5 As shown in the figure, the active voltage standing wave ratio is less than 2.3 in the entire 2-18 GHz frequency range.

[0029] The simulation results of the horizontal plane active voltage standing wave ratio changing with frequency are as follows Figure 6 As shown in the figure, the active voltage standing wave ratio is less than 3.2 in the entire 2-18 GHz frequency range.

[0030] The vertical and horizontal gain unit patterns at 18 GHz at a scan angle of 0° are as follows: Figure 7 As shown, the cross-polarization performance is good and the waveform is normal.

[0031] The vertical radiation pattern of the 9×9 antenna array at 14GHz frequency at 0°, 30°, and 45° scanning angles is as follows Figure 8 As shown, the beam is stable, the pointing is accurate, and the cross-polarization performance is good.

[0032] The horizontal plane radiation pattern of the 9×9 antenna array at 14GHz frequency at 0°, 30°, and 45° scanning angles is as follows Figure 9 As shown, the beam is stable, the pointing is accurate, and the cross-polarization performance is good.

[0033] By adopting an all-metal antenna unit loaded with a metasurface structure, ultra-wideband working bandwidth performance is achieved without the need to design a complex feeding network. It has the advantages of low profile and easy conformality.

[0034] The above are embodiments of the present invention and do not limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention are included in the protection scope of the present invention.

Claims

1. An ultra-wideband dual-polarization phased array antenna loaded with a metasurface structure, characterized in that: include: It consists of several antenna units, each extending along the X-polarization direction and the Y-polarization direction respectively, forming orthogonally arranged dipole antenna units, forming a planar array of any size. Each antenna unit is composed of a metal floor, a radiating metal arm, and a metasurface structure from bottom to top. The radiating metal arm is divided into a grounding metal arm and a feeding metal arm.

2. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 1, characterized in that: The metal floor is electrically connected to the feeding metal arm through the elastic ball head of the SMP ball head connector, current is fed into the feeding metal arm through the coaxial inner core, and equal amplitude reverse current is returned from the grounded metal arm to radiate energy into free space.

3. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 1, characterized in that: The feeding metal arm and the grounding metal column are asymmetrical structures, which increases the structural freedom of the antenna unit.

4. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 1, characterized in that: The periphery of the radiation metal arm is provided with a plurality of elliptical holes for adjusting the impedance matching of the antenna within the ultra-wideband working bandwidth.

5. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 1, characterized in that: The metasurface structure is made of polyimide, with an air gap between it and the radiating metal arm, and is supported and fixed by foam.

6. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 1, characterized in that: A circuit pattern is printed on the upper surface of the metasurface structure to change the equivalent dielectric constant of the polyimide film and adjust the low-frequency impedance matching of the antenna when scanning at a large angle.

7. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 4, characterized in that: The upper part of the radiating metal arm has four standard elliptical grooves with a short diameter of 1.15 mm and long diameters of 4.03 mm, 1.76 mm, 1.5 mm, and 1.15 mm from top to bottom, respectively. The ratios of long to short diameters are 3.5:1, 1.5:1, 1.3:1, and 1:

1.

8. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 7, characterized in that: The width of the gap between the radiation metal arms is 0.35 mm.

9. The ultra-wideband dual-polarized phased array antenna loaded with a metasurface structure according to claim 1, characterized in that: The polyimide thickness of the metasurface structure is 0.05 mm, the air gap between the metasurface structure and the radiating metal arm is 1 mm, and the printed pattern thickness is 0.05 mm.

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