A directional pattern reconfigurable antenna based on bistable structure

Abstract

The application discloses a kind of based on bistable structure's directional diagram reconfigurable antenna in the field of antenna, including bistable bending structure and dielectric substrate;The upper surface of the dielectric substrate is equipped with metal bottom plate;Metal bottom plate top is provided with bistable bending structure;The top of the bistable bending structure is equipped with polygonal metal ring;Bistable bending structure surface is provided with several metal strips;Each metal strip electrically connected the polygonal metal ring forms multi-arm spiral antenna, the dielectric substrate below is provided with coaxial feed structure, the metal probe in the coaxial feed structure passes through dielectric substrate and metal bottom plate, and electrically connected to the metal strip;The application has the characteristics of low cost, light, portability and high flexibility, when the bistable bending structure changes steady-state configuration, realizes antenna directional diagram substantial reconfiguration.

Description

Technical Field

[0001] This invention belongs to the field of radiating antenna technology, specifically relating to a pattern reconfigurable antenna based on a bistable structure. Background Technology

[0002] With the continuous upgrading of wireless communication systems and the increasing diversity of users and application demands, the fixed structure and operating frequency band of traditional antennas can no longer meet the complex and ever-changing communication environments and requirements. To solve this problem, reconfigurable antennas have emerged. By dynamically adjusting the antenna's structure or parameters, they can reconfigure various characteristics such as frequency, radiation pattern, and polarization, thereby adapting to different communication needs.

[0003] Currently, reconfigurable antenna implementation technologies are mainly divided into two categories: electronic switching technology and mechanical deformation technology. Electronic switching technology has the advantages of easy integration and rapid response, but its reliance on electronic components can lead to stability issues and a small range of reconfiguration direction changes, reducing reliability during application. While mechanical deformation technology offers high reliability and a large range of reconfiguration direction changes, it requires additional mechanical transmission devices and servo systems, increasing system complexity and manufacturing costs.

[0004] In summary, existing technologies struggle to reconstruct reliability, flexibility, and manufacturing costs simultaneously, limiting their widespread adoption in practical applications. Therefore, optimizing the design of reconfigurable antennas to reduce complexity and cost while improving flexibility and reliability has become a pressing technical challenge. Summary of the Invention

[0005] The purpose of this invention is to provide a pattern reconfigurable antenna based on a bistable structure, which features low cost, lightweight, portability and high flexibility, and achieves significant antenna pattern reconfiguration.

[0006] To achieve the above objectives, the first aspect of the present invention provides a pattern reconfigurable antenna based on a bistable structure, comprising a bistable bending structure and a dielectric substrate; a metal base plate is provided on the upper surface of the dielectric substrate; a bistable bending structure is disposed above the metal base plate; and a polygonal metal ring is provided at the top of the bistable bending structure. The surface of the bistable bending structure is provided with a plurality of metal strips; each metal strip is electrically connected to the polygonal metal ring to form a multi-arm spiral antenna; a coaxial feed structure is provided below the dielectric substrate; a metal probe in the coaxial feed structure passes through the dielectric substrate and the metal base plate and is electrically connected to the metal strips; when the bistable bending structure changes its steady-state configuration, the radiation pattern of the multi-arm spiral antenna is reconstructed.

[0007] Furthermore, the bistable bending structure is provided with multiple bendable surfaces, each bendable surface including an upper connecting part, a lower connecting part, and a bending part; the upper connecting part and the lower connecting part of each bendable surface are connected end to end; The bending section includes a bendable upper triangular plate and a lower triangular plate. The upper triangular plate is connected to the upper connecting section, and the lower triangular plate is connected to the lower connecting section. The individual side lengths of the upper and lower triangular plates overlap and are connected to each other, and the connection between the upper and lower triangular plates can be bent.

[0008] Furthermore, the upper and lower triangles are identical in shape and size.

[0009] Furthermore, the bendable surface is configured to correspond one-to-one with the side length of the polygonal metal ring.

[0010] Furthermore, the bendable surfaces are configured in a one-to-one correspondence with the metal strips.

[0011] Furthermore, the bistable bending structure includes a first stable configuration and a second stable configuration; when the bistable bending structure changes from the first stable configuration to the second stable configuration, the polygonal metal ring twists 90 degrees counterclockwise; when the bistable bending structure changes from the second stable configuration to the first stable configuration, the polygonal metal ring twists 90 degrees clockwise.

[0012] Furthermore, the metal strip is inclined, with the lower half of the metal strip attached to the lower triangular plate and the upper half of the metal strip attached to the upper triangular plate.

[0013] Furthermore, the coaxial power supply structure includes an outer conductor, an insulator, and a metal probe; the insulator is sleeved outside the metal probe, the outer conductor is sleeved outside the insulator, and the outer conductor and the metal probe are coaxially arranged.

[0014] Furthermore, the metal base plate and the dielectric substrate are provided with through holes for the metal probe to pass through; the through holes are coaxially arranged with the metal probe.

[0015] Furthermore, the dielectric constant of the bistable bending structure is set to [2.0, 10.0]; the dielectric constant of the dielectric substrate is set to [2.0, 10.0]; the upper connecting part, lower connecting part, and bending part in the bistable bending structure all have a thickness h1, and the value range of thickness h1 is [0.001λ0, 0.01λ0]; the thickness h2 of the dielectric substrate is set to [0.002λ0, 0.02λ0], where λ0 is the free space wavelength.

[0016] Furthermore, the lateral distance S1 between the lower left corner vertex of the metal strip and the lower left corner vertex of the bendable surface is set to [0.01λ0, 0.03λ0]; the lateral distance S2 between the upper right corner vertex of the metal strip and the upper right corner vertex of the bendable surface is set to [0.01λ0, 0.03λ0]. The width W1 of the metal strip is set to [0.005λ0, 0.015λ0]; the width W2 of the polygonal metal ring is set to [0.005λ0, 0.015λ0], where λ0 is the free space wavelength.

[0017] Furthermore, the side length L1 of the metal base plate is set to [0.35λ0, 0.8λ0], the side length L2 of the bistable bending structure is set to [0.18λ0, 0.36λ0], the lateral distance L3 between the bistable bending structure and the edge of the metal base plate is set to [0.13λ0, 0.26λ0], and the height H of the bistable bending structure is set to [0.3λ0, 0.8λ0], where λ0 is the free space wavelength.

[0018] A second aspect of the present invention provides a method for manufacturing a pattern-reconfigurable antenna, comprising: A bistable bending structure is formed by bending, cutting and bonding rectangular insulating boards. A polygonal metal ring is attached to the upper connecting part, and several metal strips are respectively attached to the bending parts of each bendable surface, and the polygonal metal ring is connected to form a multi-arm spiral antenna. A metal base plate is attached to a dielectric substrate, and through holes are made in the dielectric substrate and the metal base plate; a bistable bending structure is fixedly installed on the metal base plate. The metal probes within the coaxial feed structure pass through through holes in the dielectric substrate and the metal base plate and are connected to the metal strip.

[0019] Furthermore, the rectangular insulating material is bent, cut, and bonded to form a bistable bending structure, specifically including: The bistable bending structure has multiple bendable surfaces, each bendable surface including an upper connecting part, a lower connecting part, and a bending part; the upper connecting parts and lower connecting parts of each bendable surface are connected end to end; the bending part is a bendable upper triangular plate and a lower triangular plate. A rectangular insulating board is bent to form several bendable surfaces of the same size, and the bendable surfaces are arranged side by side. The surface of the unit is bent to form an upper connecting part, a bent part and a lower connecting part; the bent part is cut to form an upper triangular plate and a lower triangular plate, and the single side length of the upper triangular plate and the lower triangular plate overlap and connect to each other, and the connection between the upper triangular plate and the lower triangular plate can be bent; The bendable surfaces at both ends of a rectangular insulating board are bonded together to form a bistable bending structure.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: The bistable bending structure described in this invention has a polygonal metal ring at its top; several metal strips are disposed on the surface of the bistable bending structure; each metal strip is electrically connected to the polygonal metal ring to form a multi-arm spiral antenna; a coaxial feed structure is disposed below the dielectric substrate; a metal probe in the coaxial feed structure passes through the dielectric substrate and the metal base plate and is electrically connected to the metal strips; when the bistable bending structure changes its steady-state configuration, the radiation pattern of the multi-arm spiral antenna is reconstructed; using the bistable structure to achieve radiation pattern reconstruction eliminates the need for complex electronic control equipment and a large number of feed networks, reducing the complexity and cost of the system; the design of the bistable structure ensures that the transition between the two steady-state configurations is stable and repeatable, and will not easily change its state due to external interference, thus improving the reliability and stability of the antenna. Attached Figure Description

[0021] Figure 1 This is a first steady-state configuration diagram of the pattern-reconfigurable antenna provided in Example 1; Figure 2 This is a second steady-state configuration diagram of the pattern-reconfigurable antenna provided in Example 1; Figure 3 This is a front view of the pattern-reconfigurable antenna provided in Example 1; Figure 4 A top view of the pattern-reconfigurable antenna provided in Embodiment 1; Figure 5 This is an unfolded diagram of the bistable bending structure provided in Example 1; Figure 6 A physical diagram of the bistable bending structure provided in Example 1; Figure 7 The |S11| curves of the pattern reconfigurable antenna provided in Example 1 in two steady-state configurations; Figure 8 The radiation pattern of the pattern-reconfigurable antenna provided in Example 1 when it is in the first steady-state configuration at 1.44 GHz; Figure 9 The radiation pattern of the pattern-reconfigurable antenna provided in Example 1 when it is in the second steady-state configuration at 1.44 GHz; Figure 10 The normalized half-power beamwidth rectangles in the xz plane for the pattern reconfigurable antenna provided in Example 1 when it is in the first steady-state configuration at 1.44 GHz and the second steady-state configuration at 1.14 GHz; Figure 11The yz plane normalized half-power beamwidth rectangles of the pattern reconfigurable antenna provided in Example 1 when it is in the first steady-state configuration at 1.44 GHz and the second steady-state configuration at 1.14 GHz; Figure 12 The axial ratio radiation patterns of the pattern reconfigurable antenna provided in Example 1 in the first and second steady-state configurations; In the figure: 1 is a bistable bending structure, 11 is the upper connecting part, 12 is the bending part, 121 is the upper triangular plate, 122 is the lower triangular plate, 13 is the lower connecting part, 2 is a metal strip, 3 is a polygonal metal ring, 4 is a dielectric substrate, 41 is a metal base plate, 42 is a through hole, 5 is a coaxial feeding structure, 51 is a metal probe, 52 is an insulating layer, and 53 is an outer conductor. Detailed Implementation

[0022] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0023] It should be noted that in the description of this invention, the terms "front," "rear," "left," "right," "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. The terms "front," "rear," "left," "right," "upper," and "lower" used in the description of this invention refer to the directions shown in the accompanying drawings, while the terms "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0024] Example 1

[0025] like Figures 1 to 6 As shown, a pattern reconfigurable antenna based on a bistable structure includes a bistable bending structure 1 and a dielectric substrate 4; a metal base plate 41 is provided on the upper surface of the dielectric substrate 4; through holes 42 for metal probes to pass through are provided on the metal base plate 41 and the dielectric substrate 4; in this embodiment, the through hole 42 and the metal probe 51 are coaxially arranged.

[0026] A bistable bending structure 1 is provided above the metal base plate 41; the bistable bending structure 1 is provided with multiple bendable surfaces, each bendable surface including an upper connecting part 11, a lower connecting part 13 and a bending part 12; the upper connecting part 11 and the lower connecting part 13 of each bendable surface are connected end to end; The bending portion 12 includes a bendable upper triangular plate 121 and a lower triangular plate 122. In this embodiment, the upper triangular plate 121 and the lower triangular plate 122 have the same shape and size. The upper triangular plate 121 is connected to the upper connecting portion 11, and the lower triangular plate 122 is connected to the lower connecting portion 13. The single side lengths of the upper triangular plate 121 and the lower triangular plate 122 overlap and are connected to each other. The connection between the upper triangular plate 121 and the lower triangular plate 122 can be bent.

[0027] The top of the bistable bending structure 1 is provided with a polygonal metal ring 3; the bendable surface is set in a one-to-one correspondence with the side length of the polygonal metal ring 3.

[0028] The surface of the bistable bending structure 1 is provided with a plurality of metal strips 2; the bendable surface is provided in a one-to-one correspondence with the metal strips 2. The metal strips 2 are inclined, and the lower half of the metal strips 2 is attached to the lower triangular plate 122, and the upper half of the metal strips 2 is attached to the upper triangular plate 121.

[0029] Each metal strip 2 is electrically connected to the polygonal metal ring 3 to form a multi-arm helical antenna. A coaxial feed structure 5 is disposed below the dielectric substrate 4. The coaxial feed structure 5 includes an outer conductor 53, an insulator 52, and a metal probe 51. The insulator sleeve 52 is disposed outside the metal probe 51, and the outer conductor sleeve 53 is disposed outside the insulator sleeve 52. The outer conductor 53 and the metal probe 51 are coaxially arranged. The metal probe 51 in the coaxial feed structure passes through the dielectric substrate 4 and the metal base plate 41 and is electrically connected to the metal strip 2.

[0030] When the bistable bending structure 1 changes its steady-state configuration, the radiation pattern of the multi-arm spiral antenna is reconstructed. In this embodiment, the bistable bending structure 1 includes a first steady-state configuration and a second steady-state configuration. When the bistable bending structure 1 changes from the first steady-state configuration to the second steady-state configuration, the polygonal metal ring 3 twists 90 degrees counterclockwise; when the bistable bending structure 1 changes from the second steady-state configuration to the first steady-state configuration, the polygonal metal ring 3 twists 90 degrees clockwise. The design of the bistable structure in this embodiment ensures that the transition between the two steady-state positions is stable and repeatable, and will not easily change its state due to external interference, thus improving the reliability and stability of the antenna.

[0031] The dielectric constant of the bistable bending structure 1 is set to [2.0, 10.0]; the dielectric constant of the dielectric substrate 4 is set to [2.0, 10.0]; the upper connecting part, lower connecting part and bending part in the bistable bending structure are all of thickness h1, and the value range of thickness h1 is [0.001λ0, 0.01λ0]; the thickness h2 of the dielectric substrate is set to [0.002λ0, 0.02λ0], where λ0 is the free space wavelength.

[0032] The lateral distance S1 between the lower left corner vertex of the metal strip 2 and the lower left corner vertex of the bendable surface is set to [0.01λ0, 0.03λ0]; the lateral distance S2 between the upper right corner vertex of the metal strip 2 and the upper right corner vertex of the bendable surface is set to [0.01λ0, 0.03λ0]. The width W1 of the metal strip 2 is set to [0.005λ0, 0.015λ0]; the width W2 of the polygonal metal ring 3 is set to [0.005λ0, 0.015λ0], where λ0 is the free space wavelength.

[0033] The side length L1 of the metal base plate 41 is set to [0.35λ0, 0.8λ0], the side length L2 of the bistable bending structure 1 is set to [0.18λ0, 0.36λ0], the lateral distance L3 between the bistable bending structure 1 and the edge of the metal base plate 41 is set to [0.13λ0, 0.26λ0], and the height H of the bistable bending structure 1 is set to [0.3λ0, 0.8λ0], where λ0 is the free space wavelength.

[0034] In this embodiment, the specific parameters are set as follows: the thickness h1 of the bistable twisted origami structure is 0.5 mm; the thickness h2 of the dielectric substrate is 1 mm; the distance S1 between the lower left corner vertex of the metal strip and the lower left corner vertex of the surface of the bistable twisted origami structure is 5 mm; the distance S2 between the upper right corner vertex of the metal strip and the upper right corner vertex of the surface of the bistable twisted origami structure is 5 mm; the width W1 of the metal strip is 2.5 mm; and the width W2 of the metal annular strip is 2.5 mm.

[0035] The side length L1 of the square metal floor is 100mm, the side length L2 of the bottom square of the bistable torsion origami structure is 40mm, the distance L3 between the bistable torsion origami structure and the edge of the square metal floor is 30mm, and the height H of the bistable torsion origami structure is 80mm.

[0036] The diameter R1 of the circular hole etched on the metal floor is 3mm, and the diameter of the metal probe used for power supply is 0.6mm. The circular hole and the metal probe are concentric, and the center of the circular hole coincides with the midpoint of the bottom of the metal strip.

[0037] like Figures 7 to 12 As shown, the radiation patterns of the bistable antenna in the first and second steady-state configurations can be calculated using electromagnetic simulation software. Both configurations exhibit normal radiation capability and good circular polarization characteristics within the operating frequency band.

[0038] Table 1. Comparison of antenna performance under two steady states;

[0039] In this embodiment, both the first and second steady-state configurations radiate in the positive z-axis direction. By rotating, the antenna is transformed from the first steady-state configuration to the second steady-state configuration, resulting in a change in the surface metal radiation strip structure. The 3dB beamwidth in both the xz and yz planes changes by 62°, and the matching gain changes by 2.88dBi, as shown in Table 1. The antenna pattern beamwidth is successfully reconfigurable, and the matching is good in each operating frequency band.

[0040] In this embodiment, in a multi-user environment, the reconfigurable antenna can flexibly adjust its radiation pattern according to the location and needs of different users, achieving efficient coverage for multiple users and increasing the system's communication capacity. Utilizing a bistable structure for radiation pattern reconfiguration eliminates the need for complex electronic control equipment and extensive feed networks, reducing system complexity and cost. The simple design also makes the antenna easier to manufacture and maintain, reducing the risk of failure and maintenance costs associated with complex electronic components.

[0041] Example 2 This embodiment provides a method for fabricating a pattern-reconfigurable antenna. The method described in this embodiment is used to fabricate the pattern-reconfigurable antenna described in Embodiment 1. The fabrication method includes: The process of bending, cutting, and bonding rectangular insulating sheets to form a bistable bending structure includes: The rectangular insulating board is a cardboard or plastic board. The rectangular insulating board is bent to form several bendable surfaces of the same size, and the bendable surfaces are arranged side by side. The surface of the unit is bent to form an upper connecting part 11, a bent part 12 and a lower connecting part 13; the bent part 12 is cut to form an upper triangular plate 121 and a lower triangular plate 122, and the single side length of the upper triangular plate 121 and the lower triangular plate 122 overlap and are connected to each other, and the connection between the upper triangular plate 121 and the lower triangular plate 122 can be bent. The bendable surfaces at both ends of a rectangular insulating board are bonded together to form a bistable bending structure 1; A polygonal metal ring 3 is attached to the upper connecting part 11; several metal strips 2 are respectively attached to the bending parts 12 of each bendable surface, and connected to the polygonal metal ring 3 to form a multi-arm spiral antenna. A metal base plate 41 is attached to a dielectric substrate 4, and through holes 42 are formed in the dielectric substrate 4 and the metal base plate 41; a bistable bending structure 1 is fixedly installed on the metal base plate 41. The metal probe 51 in the coaxial feed structure 5 passes through the through hole 42 on the dielectric substrate and the metal base plate and is connected to the metal strip 2.

[0042] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A pattern-reconfigurable antenna based on a bistable structure, characterized in that, It includes a bistable bending structure and a dielectric substrate; a metal base plate is provided on the upper surface of the dielectric substrate; a bistable bending structure is provided above the metal base plate; a polygonal metal ring is provided on the top of the bistable bending structure; The surface of the bistable bending structure is provided with a plurality of metal strips; each metal strip is electrically connected to the polygonal metal ring to form a multi-arm spiral antenna; a coaxial feed structure is provided below the dielectric substrate; a metal probe in the coaxial feed structure passes through the dielectric substrate and the metal base plate and is electrically connected to the metal strips; when the bistable bending structure changes its steady-state configuration, the radiation pattern of the multi-arm spiral antenna is reconstructed. The bistable bending structure has multiple bendable surfaces, each bendable surface including an upper connecting part, a lower connecting part, and a bending part; the upper connecting parts and lower connecting parts of each bendable surface are connected end to end; The bending section includes a bendable upper triangular plate and a lower triangular plate. The upper triangular plate is connected to the upper connecting section, and the lower triangular plate is connected to the lower connecting section. The individual side lengths of the upper and lower triangular plates overlap and are connected to each other, and the connection between the upper and lower triangular plates can be bent. The metal strip is inclined, with the lower half of the metal strip attached to the lower triangular plate and the upper half of the metal strip attached to the upper triangular plate.

2. The pattern-reconfigurable antenna according to claim 1, characterized in that, The bendable surface is configured to correspond one-to-one with the side length of the polygonal metal ring; the bendable surface is configured one-to-one with the metal strip.

3. The pattern-reconfigurable antenna according to claim 1, characterized in that, The bistable bending structure includes a first stable configuration and a second stable configuration; when the bistable bending structure changes from the first stable configuration to the second stable configuration, the polygonal metal ring is twisted 90 degrees counterclockwise; when the bistable bending structure changes from the second stable configuration to the first stable configuration, the polygonal metal ring is twisted 90 degrees clockwise.

4. The pattern-reconfigurable antenna according to claim 1, characterized in that, The dielectric constant of the bistable bending structure is set to [2.0, 10.0]; the dielectric constant of the dielectric substrate is set to [2.0, 10.0]; the upper connecting part, lower connecting part and bending part in the bistable bending structure are all of thickness h1, and the value range of thickness h1 is [0.001λ0, 0.01λ0]; the thickness h2 of the dielectric substrate is set to [0.002λ0, 0.02λ0], where λ0 is the free space wavelength.

5. The pattern-reconfigurable antenna according to claim 1, characterized in that, The lateral distance S1 between the lower left corner vertex of the metal strip and the lower left corner vertex of the bendable surface is set to [0.01λ0, 0.03λ0]; the lateral distance S2 between the upper right corner vertex of the metal strip and the upper right corner vertex of the bendable surface is set to [0.01λ0, 0.03λ0]. The width W1 of the metal strip is set to [0.005λ0, 0.015λ0]; the width W2 of the polygonal metal ring is set to [0.005λ0, 0.015λ0], where λ0 is the free space wavelength.

6. The pattern-reconfigurable antenna according to claim 1, characterized in that, The side length L1 of the metal base plate is set to [0.35λ0, 0.8λ0], the side length L2 of the polygonal metal ring is set to [0.18λ0, 0.36λ0], the lateral distance L3 between the bistable bending structure and the edge of the metal base plate is set to [0.13λ0, 0.26λ0], and the height H of the bistable bending structure is set to [0.3λ0, 0.8λ0], where λ0 is the free space wavelength.

7. The method for manufacturing a pattern-reconfigurable antenna according to any one of claims 1 to 6, characterized in that, include: A bistable bending structure is formed by bending, cutting and bonding rectangular insulating boards. A polygonal metal ring is attached to the upper connecting part, and several metal strips are respectively attached to the bending parts of each bendable surface, and the polygonal metal ring is connected to form a multi-arm spiral antenna. A metal base plate is attached to a dielectric substrate, and through holes are made in the dielectric substrate and the metal base plate; a bistable bending structure is fixedly installed on the metal base plate. The metal probes within the coaxial feed structure pass through through holes in the dielectric substrate and the metal base plate and are connected to the metal strip.

8. The method for manufacturing a pattern-reconfigurable antenna according to claim 7, characterized in that, The process of bending, cutting, and bonding rectangular insulating sheets to form a bistable bending structure includes: The bistable bending structure has multiple bendable surfaces, each bendable surface including an upper connecting part, a lower connecting part, and a bending part; the upper connecting parts and lower connecting parts of each bendable surface are connected end to end; the bending part is a bendable upper triangular plate and a lower triangular plate. A rectangular insulating board is bent to form several bendable surfaces of the same size, and the bendable surfaces are arranged side by side. The surface of the unit is bent to form an upper connecting part, a bent part and a lower connecting part; the bent part is cut to form an upper triangular plate and a lower triangular plate, and the single side length of the upper triangular plate and the lower triangular plate overlap and connect to each other, and the connection between the upper triangular plate and the lower triangular plate can be bent; The bendable surfaces at both ends of a rectangular insulating board are bonded together to form a bistable bending structure.

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