E-plane decoupling two-unit metasurface indoor antenna

Abstract

The invention belongs to the technical field of antennas, and provides an E-plane decoupling two-unit metasurface indoor antenna, which comprises a first substrate structure and a second substrate structure which are stacked, wherein the first substrate structure is composed of a metasurface radiator, a first substrate and a bottom plate which are stacked in sequence; the metasurface radiator is sequentially provided with a first patch group, a second patch group and a third patch group from the two sides to the middle, and the third patch group is used for forming radiation edges on the surfaces of the two sides. The third patch group serves as a common patch group of the first patch groups on the two sides to form two separated radiation edges, each radiation edge corresponds to the first patch group on one side, when a decoupling structure is added to the third patch group shared in the middle column, radiation of the respective antenna radiation edge is not affected, and the radiation efficiency of the antenna is improved. Therefore, the influence on the impedance matching performance and the radiation performance is reduced.

Description

Technical Field

[0001] The present invention belongs to the field of antenna technology, and in particular relates to a two-unit metasurface indoor antenna with E-plane decoupling. Background Art

[0002] Metasurface antenna technology demonstrates exceptional technical advantages through its unique design concept and innovative architecture. Through the sophisticated design of the metasurface radiator, this technology achieves superior performance, including wide bandwidth and high gain, while maintaining a low profile. Compared to traditional patch antennas, metasurface antennas take a different approach, effectively increasing the radiating aperture, successfully breaking through the technical bottlenecks of bandwidth and gain improvement while maintaining a low structural profile. This gives them a significant competitive advantage in space-constrained applications.

[0003] As a cutting-edge decoupling solution, mode cancellation decoupling technology offers significant technological innovation compared to traditional defective ground technology, decoupling network technology, and neutralization line technology. This technology cleverly utilizes a set of modes existing within the radiator to superimpose on each other. Through precise phase control, it cancels out the electromagnetic fields at the unexcited ports, thereby achieving efficient decoupling. Compared to traditional decoupling methods, mode cancellation decoupling technology eliminates the need for additional complex decoupling structures or intentionally increasing antenna spacing. This not only simplifies the antenna design process but also enables a tighter arrangement of antenna elements, effectively reducing the overall size of the antenna array and providing a new approach to the design of compact antenna systems.

[0004] However, the existing decoupling technology still has certain limitations. The existing decoupling technology usually requires a certain distance between the two antennas, on the one hand to reduce the original coupling between the antennas, and on the other hand to set up various decoupling structures; in addition, the radiation of the existing metasurface antenna is mainly generated by multiple radiating edges. When one radiating edge reused between two E-plane coupled metasurface antennas is suppressed, the impedance matching performance will be deteriorated. Summary of the Invention

[0005] In order to solve the problems in the background technology, the present invention proposes a two-unit metasurface indoor antenna with E-plane decoupling.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: An E-plane decoupled two-unit metasurface indoor antenna, comprising a first substrate structure and a second substrate structure stacked together; The first substrate structure is composed of a metasurface radiator, a first substrate and a bottom plate stacked in sequence; The metasurface radiator is provided with a first patch group, a second patch group and a third patch group in sequence from both sides to the middle; The first patch group is provided with a plurality of groups, which are symmetrically arranged with the third patch group as the symmetry center; the second patch group is provided with a plurality of groups, which are symmetrically arranged with the third patch group as the symmetry center; the third patch group is provided with a group, which is used to form a radiation edge on the surface facing the second patch group; A short-circuit via is installed on the first substrate, and the short-circuit via is used to connect the third patch group and the bottom plate.

[0007] Preferably, the second substrate structure includes a second substrate and a feeding network installed on the bottom surface of the second substrate; the second substrate and the bottom plate are stacked on each other.

[0008] Preferably, the second patch group is provided with two groups, which respectively correspond to the radiation edges of the two side surfaces of the third patch group; and the third patch group is provided with six groups.

[0009] Preferably, the first patch group includes a plurality of patches distributed in an array; The second patch group includes a plurality of patches distributed in an array; The third patch group includes a plurality of patches distributed in an array, and each patch is connected to at least two of the short-circuit vias.

[0010] Preferably, the patches in the first patch group, the second patch group and the third patch group are all rectangular or square.

[0011] Preferably, the bottom plate is a metal plate.

[0012] Preferably, a plurality of slits are etched on the surface of the base plate, and the slits are used to couple the energy of the feeding network to the metasurface radiator for radiation.

[0013] Preferably, a plurality of the feed networks are arranged in parallel, and each of the feed networks is a Y-shaped structure or a linear structure.

[0014] Preferably, the Y-shaped feeding network includes an output feeder, an impedance transformation line and an input feeder; Both ends of the impedance transformation line are connected to the output feeder respectively; One end of the input feeder is connected to the middle section of the impedance transformation line.

[0015] Preferably, the short-circuit via is a metal via.

[0016] Beneficial effects of the present invention: 1. The metasurface radiator of the present invention installs the second patch group and the third patch group between the first patch groups on both sides, wherein the third patch group serves as a common patch group of the first patch groups on both sides to form two separate radiation edges, so that each radiation edge corresponds to the first patch group on one side. When a decoupling structure is added to the third patch group shared in the middle column, it will not affect the radiation of each antenna radiation edge, thereby reducing the impact on the impedance matching performance and radiation performance.

[0017] 2. The present invention uses a mode cancellation structure, and installs the second patch group and the third patch group in the gap between the first patch groups on both sides. No additional antenna spacing is required, and a more compact size can be achieved.

[0018] Other features and advantages of the present invention will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic structural diagram of a two-unit metasurface indoor antenna with E-plane decoupling according to the present invention is shown; Figure 2 A schematic structural diagram of the metasurface radiator of the present invention is shown; Figure 3 Shows a schematic structural diagram of the base plate of the present invention; Figure 4 A schematic diagram showing the structure of a Y-shaped feeding network of the present invention is shown; Figure 5 A schematic diagram showing the S-parameter simulation results of an existing E-plane coupled two-unit metasurface antenna is shown; Figure 6 A schematic diagram of the S-parameter simulation results of the E-plane decoupled two-unit metasurface indoor antenna of the present invention is shown.

[0021] In the figure: 1. metasurface radiator; 101. first patch group; 102. second patch group; 103. third patch group; 2. short-circuit via; 3. first substrate; 4. bottom plate; 401. gap; 5. second substrate; 6. feeding network; 601. output feed line; 602. impedance transformation line; 603. input feed line. DETAILED DESCRIPTION

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0023] like Figure 1 As shown, a two-unit metasurface indoor antenna with E-plane decoupling includes a first substrate structure and a second substrate structure that are stacked. Combine Figure 2 It can be seen that the first substrate structure is composed of a metasurface radiator 1, a first substrate 3 and a bottom plate 4 stacked in sequence. The metasurface radiator 1 is the core component of the antenna to achieve signal radiation, and it is sequentially provided with a first patch group 101, a second patch group 102 and a third patch group 103 from both sides to the middle. The first patch group 101 is provided with several groups, which are symmetrically arranged with the third patch group 103 as the symmetry center; the second patch group 102 is also provided with several groups, which are symmetrically arranged with the third patch group 103 as the symmetry center; and the third patch group 103 is provided with only one group, whose main function is to form a radiation edge on the surface facing the second patch group 102, and work together with the first patch group 101 and the second patch group 102 to achieve efficient signal radiation. In practical applications, this symmetrical setting method can make the antenna's radiation pattern more uniform and stable, and reduce signal attenuation and distortion.

[0024] The first substrate 3 is provided with a short-circuit via 2, which is used to achieve electrical connection between the third patch group 103 and the bottom plate 4, changing the current distribution in the antenna structure, thereby effectively reducing the electromagnetic coupling effect.

[0025] As an optional solution, short-circuit via 2 is a metal via, equivalent to a metal probe. Short-circuit via 2 enhances the ability to suppress E-plane electromagnetic coupling. In practice, short-circuit via 2 modifies the antenna's electromagnetic field distribution, significantly reducing electromagnetic coupling between antenna elements in the E-plane direction, thereby improving antenna isolation. Furthermore, the E-plane refers to the direction of electric field polarization, specifically along the long side of the metasurface radiator 1. The straight line formed by short-circuit via 2 is perpendicular to the direction indicated by the E-plane.

[0026] In addition, Figure 1The second substrate structure includes a second substrate 5 and a feed network 6 mounted on its bottom surface. The second substrate 5 and the bottom plate 4 are stacked together. The feed network 6 is responsible for introducing external signals into the antenna system and processing and distributing the signals. Several feed networks 6 are arranged in parallel, each in a Y-shaped or linear configuration.

[0027] like Figure 4 As shown, the Y-shaped feed network 6 includes an output feeder 601, an impedance transformation line 602, and an input feeder 603. The impedance transformation line 602 is connected to the output feeder 601 at both ends, while the input feeder 603 is connected to the middle section of the impedance transformation line 602 at one end. This Y-shaped feed network 6 achieves impedance matching for the input signal through the impedance transformation line 602, reducing signal reflections and improving signal transmission efficiency. For example, when the impedance of the external signal source does not match the impedance of the subsequent portion of the antenna, the impedance transformation line 602 can adjust the signal's impedance, ensuring smooth transmission to the base plate 4.

[0028] As an optional solution, the resistance of the output feeder 601 and the input feeder 603 is 50 ohms, and the resistance of the impedance transformation line 602 is 70.7 ohms.

[0029] In terms of specific structure, the second patch group 102 is provided with two groups, corresponding to the radiating edges of the two side surfaces of the third patch group 103; the third patch group 103 is provided with six groups. The patches in the first patch group 101, the second patch group 102, and the third patch group 103 are all rectangular or square, and each patch includes several patches distributed in an array. Among them, each patch in the third patch group 103 is connected to at least two short-circuit vias 2. This design can further optimize the radiation performance and decoupling effect of the antenna. For example, the array-distributed patches can increase the effective radiation area of the antenna and improve radiation efficiency. The connection method of the third patch group 103 and the multiple short-circuit vias 2 can more effectively suppress electromagnetic coupling.

[0030] like Figure 3 As shown, the base plate 4 is a metal plate with several slits 401 etched on its surface. These slits 401 are used to couple the energy of the feed network 6 to the metasurface radiator 1 for radiation. By properly adjusting the parameters of the slits 401, the energy of the feed network 6 can be efficiently transmitted to the metasurface radiator 1, avoiding energy loss.

[0031] The following describes the working process of the two-element metasurface indoor antenna with E-plane decoupling: When the antenna is operating, the signal enters the feed network 6 through the input feed line 603. After impedance matching is achieved through the impedance transformation line 602, the signal is transmitted to the base plate 4 by the output feed line 601. The slots 401 on the surface of the base plate 4 couple the energy of the feed network 6 to the metasurface radiator 1. The third patch group 103 in the metasurface radiator 1 forms radiating edges on both sides of the surface, combining with the first patch group 101 and the second patch group 102 to achieve signal radiation. At the same time, the short-circuit via 2 effectively suppresses electromagnetic coupling between antenna elements in the E-plane direction, achieving E-plane decoupling and improving the antenna's isolation and radiation performance.

[0032] like Figure 5 and Figure 6 As shown, S11 represents the reflection coefficient and |S11| is the magnitude of the reflection coefficient. It reflects the matching of the antenna port, that is, how much of the input signal is reflected back to the signal source. The smaller the |S11| value, the better the matching between the antenna and the feeder, and the less signal reflection. Figure 5 and Figure 6 In the figure, the changes of |S11| at different frequencies can be observed, thereby evaluating the matching performance of the antenna at each frequency point.

[0033] Here, S21 refers to the coupling between the two ports, specifically the energy transferred from port 1 to port 2. The decoupling mechanism of this invention aims to reduce the energy transferred from port 1 to port 2 by radiating as much energy into space as possible while maintaining an S11 reflection coefficient of less than -10 dB. Specifically, given the same |S11|, the smaller the |S21|, the more energy the antenna radiates into space. Conversely, energy transfers to the other port, resulting in less energy radiated into space.

[0034] like Figure 5 Figure 2 shows the S-parameter simulation results of a traditional E-plane coupled two-element metasurface antenna using a uniform 4×16 square patch. The figure shows that the isolation between the two antenna ports is poor, at only 15dB.

[0035] like Figure 6 As shown, the E-plane decoupling antenna proposed in the present invention can improve the isolation to 27dB while ensuring the impedance matching performance, which is 12dB higher than the non-decoupling case, and ensures that the impedance matching performance does not deteriorate significantly.

[0036] Figure 5 and Figure 6 The specific performance comparison is as follows: Reflection performance comparison exist Figure 5In the figure, the |S11| curve reaches high values at certain frequency points. For example, in the gray-shaded frequency band, |S11| fluctuates around -10dB, indicating that the signal reflection is relatively large and the port matching performance is not particularly ideal.

[0037] exist Figure 6 The |S11| curve performs better overall. In the gray-shaded frequency band, the |S11| value is generally lower than -20dB, which means that in this frequency band, the antenna's signal reflection is significantly reduced, the port matching performance is better, and the input signal can be more effectively transmitted to the antenna for radiation, reducing signal loss at the port.

[0038] Transmission performance comparison exist Figure 5 In the figure, the antenna's |S21| curve fluctuates to a certain extent throughout the frequency band, and the value is higher in the gray shaded frequency band, indicating that there is a certain loss in the signal during transmission.

[0039] exist Figure 6 In the figure, the antenna's |S21| curve has lower values in the gray-shaded frequency band, indicating greater signal transmission loss from one unit to the other. This invention provides decoupling between two-port antennas. In addition to the reflection coefficient reflected back to the port, the input signal is divided into S21 transmitted to the other port and energy radiated into space. To maximize energy radiation into space, |S21| needs to be as small as possible.

[0040] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A two-element metasurface indoor antenna with E-plane decoupling, characterized in that: comprising a first substrate structure and a second substrate structure which are stacked; The first substrate structure is composed of a metasurface radiator (1), a first substrate (3) and a bottom plate (4) stacked in sequence; The metasurface radiator (1) is provided with a first patch group (101), a second patch group (102) and a third patch group (103) in sequence from both sides toward the middle; The first patch group (101) is provided with a plurality of groups, which are symmetrically arranged with the third patch group (103) as the symmetry center; the second patch group (102) is provided with a plurality of groups, which are symmetrically arranged with the third patch group (103) as the symmetry center; the third patch group (103) is provided with a group, which is used to form a radiation edge on the surface facing the second patch group (102); A short-circuit via (2) is installed on the first substrate (3), and the short-circuit via (2) is used to connect the third patch group (103) and the bottom plate (4).

2. The E-plane decoupled two-unit metasurface indoor antenna according to claim 1, characterized in that: The second substrate structure comprises a second substrate (5) and a feed network (6) installed on the bottom surface of the second substrate (5); the second substrate (5) and the bottom plate (4) are stacked on each other.

3. The two-unit metasurface indoor antenna with E-plane decoupling according to claim 1, characterized in that: The second patch group (102) is provided with two groups, respectively corresponding to the radiation edges of the two side surfaces of the third patch group (103); the third patch group (103) is provided with six groups.

4. The E-plane decoupled two-unit metasurface indoor antenna according to claim 1, characterized in that: The first patch group (101) includes a plurality of patches distributed in an array; The second patch group (102) includes a plurality of patches distributed in an array; The third patch group (103) includes a plurality of patches distributed in an array, and each patch is connected to at least two of the short-circuit vias (2).

5. The E-plane decoupled two-unit metasurface indoor antenna according to claim 4, characterized in that: The patches in the first patch group (101), the second patch group (102) and the third patch group (103) are all rectangular or square.

6. The E-plane decoupled two-unit metasurface indoor antenna according to claim 1, characterized in that: The bottom plate (4) is a metal plate.

7. The E-plane decoupled two-unit metasurface indoor antenna according to claim 1, characterized in that: A plurality of slits (401) are etched on the surface of the base plate (4), and the slits (401) are used to couple the energy of the feeding network (6) to the metasurface radiator (1) for radiation.

8. The E-plane decoupled two-unit metasurface indoor antenna according to claim 2, characterized in that: A plurality of the feed networks (6) are arranged in parallel, and each feed network (6) is a Y-shaped structure or a linear structure.

9. The E-plane decoupled two-unit metasurface indoor antenna according to claim 8, characterized in that: The Y-shaped feeding network (6) comprises an output feeder (601), an impedance transformation line (602) and an input feeder (603); Both ends of the impedance transformation line (602) are respectively connected to the output feeder line (601); One end of the input feeder line (603) is connected to the middle section of the impedance transformation line (602).

10. The E-plane decoupled two-unit metasurface indoor antenna according to any one of claims 1 to 9, characterized in that: The short-circuit via (2) is a metal via.

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