A novel reconfigurable intelligent metasurface antenna based on liquid crystal

Abstract

The present invention relates to a novel liquid crystal-based reconfigurable intelligent metasurface unit structure. From bottom to top, it comprises a first dielectric layer, a ground layer, a liquid crystal layer, a reflective patch structure layer, and a second dielectric layer. A multi-resonant structure is provided on the reflective patch structure layer to increase the phase shift of the intelligent metasurface unit structure, while a double-layered annular pipe is provided on the liquid crystal layer to adjust the reflection phase of the intelligent metasurface unit structure. This invention achieves dynamic phase modulation and offers advantages such as high control accuracy, a wide phase shift range, a large operating bandwidth, and high integration. It further expands the design and application of reconfigurable metasurface antennas.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a liquid crystal-based information reconfigurable intelligent metasurface antenna. Background Art

[0002] Precise control of electromagnetic waves has long been a goal of modern antenna development. However, due to the relatively fixed electromagnetic parameters of materials, this control has been limited to transmitters and receivers. In recent years, intelligent metasurfaces (RIS), which offer the ability to flexibly manipulate electromagnetic properties in a channel environment, have garnered widespread attention within the industry. RIS consist of a large array of specially designed electromagnetic units. By applying control signals to adjustable elements within these units, the electromagnetic properties of the units are dynamically controlled, enabling active and intelligent manipulation of electromagnetic waves in space, achieving dynamic control of phase, amplitude, polarization, and frequency. The introduction of RIS transforms wireless propagation from passive adaptation to active control, greatly facilitating the artificial manipulation of electromagnetic waves. However, conventional metasurfaces face a key challenge: after fabrication, their electromagnetic properties and functionality are severely limited, enabling only fixed control functions. For example, reflective metasurfaces, for example, have fixed beam pointing upon fabrication, making electronically controlled scanning like phased array antennas impossible.

[0003] Traditional metasurface research focuses on passive designs. Once fabricated, their functionality is fixed, enabling only fixed control of electromagnetic waves. For example, after processing, traditional reflective metasurfaces have fixed beam pointing directions, making them incapable of flexible electronic scanning of phased array antennas. Furthermore, current reconfigurable metasurface antennas still suffer from high sidelobe levels, low phase control accuracy, and poor beamforming capabilities, making them difficult to meet the precise electromagnetic wave control requirements of modern intelligent metasurface antennas. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a new type of reconfigurable intelligent metasurface antenna based on liquid crystal, which solves the shortcomings of the prior art.

[0005] The object of the present invention is achieved through the following technical solutions: a novel reconfigurable intelligent metasurface unit structure based on liquid crystal, which comprises, from bottom to top, a first dielectric layer, a ground layer, a liquid crystal layer, a reflective patch structure layer, and a second dielectric layer;

[0006] A multi-resonance structure is set on the reflective patch structure layer to increase the phase shift of the smart metasurface unit structure, and a double-layer ring pipe is set on the liquid crystal layer to adjust the reflection phase of the smart metasurface unit structure.

[0007] The reflective patch structure layer includes an upper patch and a multi-resonance structure arranged on the upper surface to meet the multi-bit phase quantization requirements and achieve sufficient phase shift.

[0008] The upper patch includes a lantern-shaped opening patch, and the multi-resonance structure is arranged in the middle position of the lantern-shaped opening patch.

[0009] The inner annular pipe and the outer annular pipe are filled with liquid crystal, and the reflection phase of the smart metasurface unit structure is increased by adjusting the distance between the inner annular pipe and the outer annular pipe.

[0010] An opening is provided on each side of the outer annular pipe, and connection between two adjacent intelligent metasurface unit structures is achieved through the opening.

[0011] A new type of reconfigurable intelligent metasurface antenna based on liquid crystal includes multiple intelligent metasurface unit structures, and the multiple intelligent metasurface unit structures are arranged in an array.

[0012] The present invention has the following advantages: a new type of reconfigurable intelligent metasurface antenna based on liquid crystal, which realizes dynamic phase adjustment and has the advantages of high control accuracy, wide phase shift range, large working bandwidth, and high integration, further expanding the design scheme and application mode of reconfigurable metasurface antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of the intelligent metasurface unit structure of the present invention;

[0014] Figure 2 Schematic diagram of a top view of the reflective patch structure layer;

[0015] Figure 3 is a schematic structural diagram of the liquid crystal layer;

[0016] Figure 4 A schematic structural diagram of the present invention

[0017] In the figure: 1-first dielectric layer, 2-ground layer, 3-liquid crystal layer, 4-reflective patch structure layer, 5-second dielectric layer, 6-liquid crystal, 7-inner annular pipe, 8-outer annular pipe, 9-upper patch, 10-multi-resonance structure, 11-opening. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present application provided below in conjunction with the drawings is not intended to limit the scope of protection of the present application for which protection is claimed, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application. The present invention is further described below in conjunction with the drawings.

[0019] One embodiment of the present invention relates to a new type of reconfigurable intelligent metasurface unit structure based on liquid crystal, which is used in the Ka band. When designing the metasurface unit, the unit size is required to be as small as possible, and the unit size is generally required to be less than half the wavelength of the operating frequency. Secondly, in order to meet the requirements of multi-bit phase quantization, reduce sidelobes, improve gain and beamforming effects, it is necessary to achieve sufficient phase shift in the unit design. Therefore, the present invention designs a multi-resonance structure 10 to increase the phase shift of the metasurface unit structure without expanding the size of the unit structure. Because the unit structure will have a larger phase shift at the resonance point, superimposing two adjacent resonance point structures will also cause their phase shifts to be superimposed, thereby increasing the phase shift range.

[0020] like Figure 1 As shown, the intelligent metasurface unit structure includes, from bottom to top, a first dielectric layer 1, a ground layer 2, a liquid crystal layer 3, a reflective patch structure layer 4, and a second dielectric layer 5; wherein, the first dielectric layer 1 and the second dielectric layer 5 are both glass.

[0021] The phase shift of the smart metasurface unit structure is increased by arranging a multi-resonance structure 10 on the reflective patch structure layer 4, and the reflection phase of the smart metasurface unit structure is adjusted by arranging a double-layer annular pipe on the liquid crystal layer 3.

[0022] Furthermore, if Figure 2 As shown, the reflective patch structure layer 4 includes an upper patch 9 and a multi-resonance structure 10 arranged on the upper surface to meet the multi-bit phase quantization requirements and achieve sufficient phase shift.

[0023] Among them, the upper patch 9 includes a lantern-shaped open patch, and the multi-resonance structure 10 is arranged in the middle position of the lantern-shaped open patch; the multi-resonance structure 10 is composed of two adjacent resonant structures superimposed, one of which is a square structure and the other is a circular structure. The two resonant structures are superimposed to increase the phase shift amount.

[0024] Furthermore, if Figure 3 As shown, the inner annular pipe 7 and the outer annular pipe 8 are filled with liquid crystal 6. By adjusting the distance between the inner annular pipe 7 and the outer annular pipe 8 d The electrically tunable nature of liquid crystal 6 is reflected in its ability to change the resonant frequency as the dielectric constant changes when used as a microwave device substrate. This is the basis for liquid crystal 6 to be an electrically tunable material.

[0025] An opening 11 is provided on each side of the outer annular pipe 8 , and the connection between two adjacent intelligent metasurface unit structures is achieved through the opening 11 .

[0026] When designing a reconfigurable reflective metasurface, electrically controlled switching devices are generally used to achieve changes in the phase of the reflective unit. n electrically controlled switches are n-bit encoding. At this time, one unit has 2n states, and the phase difference between two adjacent states is 360° / 2n. For example, a 2-bit unit uses four digital coding states "00", "01", "10", and "11" to represent the four phase response states of 0°, 90°, 180°, and 270°. When all metasurface units are represented by digital codes, their electromagnetic response patterns can be converted into digital coding sequences. Combined with field programmable modules such as FPGA, the electromagnetic functions of the metasurface can be switched to achieve reflected wave beamforming. Based on the above principles, the number of coding states n and the phase shift φ of adjacent units must satisfy , 3-bit phase quantization can be used to form an array based on antenna performance and quantity requirements.

[0027] Therefore, if Figure 4 As shown, another embodiment of the present invention relates to a new type of reconfigurable smart metasurface antenna based on liquid crystal, characterized in that it includes multiple smart metasurface unit structures involved in the first embodiment, and the multiple smart metasurface unit structures are arranged in a 4×4 array.

[0028] The foregoing description is merely a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Rather, the present invention is capable of various other combinations, modifications, and improvements, and is capable of modifications within the scope of the concepts described herein, through the above teachings, or through techniques or knowledge in the relevant fields. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention are intended to be within the scope of the appended claims.

Claims

1. A novel liquid crystal-based reconfigurable intelligent metasurface unit structure, characterized by: It includes, from bottom to top, a first dielectric layer (1), a ground layer (2), a liquid crystal layer (3), a reflective patch structure layer (4), and a second dielectric layer (5); The phase shift of the smart metasurface unit structure is increased by arranging a multi-resonance structure (10) on the reflective patch structure layer (4), and the reflection phase of the smart metasurface unit structure is adjusted by arranging a double-layer annular pipe on the liquid crystal layer (3); The reflective patch structure layer (4) includes an upper patch (9) and a multi-resonance structure (10) arranged on the upper surface to meet the multi-bit phase quantization requirements and achieve a sufficient phase shift amount; The upper patch (9) includes a lantern-shaped opening patch, and the multi-resonance structure (10) is arranged in the middle of the lantern-shaped opening patch. The multi-resonance structure (10) is formed by superimposing two adjacent resonant structures, one of which is a square structure and the other is a circular structure. The two resonant structures are superimposed to increase the phase shift amount. The double-layer annular pipe comprises an inner annular pipe (7) and an outer annular pipe (8), wherein the inner annular pipe (7) is filled with liquid crystal (6), and the reflection phase of the intelligent metasurface unit structure is increased by adjusting the distance between the inner annular pipe (7) and the outer annular pipe (8).

2. The novel liquid crystal-based reconfigurable intelligent metasurface unit structure according to claim 1, characterized in that: An opening (11) is provided on each side of the outer annular pipe (8), and connection between two adjacent intelligent super-surface unit structures is achieved through the opening (11).

3. A new liquid crystal-based reconfigurable smart metasurface antenna, characterized by: It comprises a plurality of intelligent metasurface unit structures as claimed in claim 1 or 2, and the plurality of intelligent metasurface unit structures are arranged in an array.

Images