Scale-shaped wearable patch antenna

Abstract

The invention relates to the technical field of wireless communication, in particular to a scaly wearable patch antenna, which comprises metal radiation patch units, a fabric dielectric plate, a metal ground and a coaxial feed part, each patch is cut along an E surface and an H surface to form a scale-like metal arrangement structure formed by multiple units, the 20 patches are arranged into a four-layer structure by adopting a mode of firstly arranging the H surface and then arranging the E surface, and a certain number of metal columns with the same radius are used on an overlapping region to connect adjacent patch units of the E surface and the H surface so as to ensure the formation of conducting current; by adjusting the size of each patch and the distance between the metal columns, impedance matching coaxial with 50 ohms can be achieved, and therefore it is guaranteed that the radiation characteristic is kept consistent with that of a traditional rectangular microstrip patch antenna. Compared with a conventional similar patch antenna, the antenna provided by the invention is small in size, has better flexibility, and is suitable for the design of a wearable antenna.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technologies, and particularly to a scale-shaped wearable patch antenna. Background Art

[0002] Conventional microstrip patch antennas can effectively reduce the electromagnetic waves radiated towards the human body due to their complete large ground plane, making them widely studied in wearable antennas. However, wearable devices require a small size, leaving very limited space for the antenna.

[0003] The radiation patch of the patch antenna has a large area, which leads to being easily affected by human activities after conformal to the human body. Different degrees of deformation will have different degrees of influence on the antenna performance, restricting its further application in the practical research of wearable antennas. Summary of the Invention

[0004] The purpose of the present invention is to provide a scale-shaped wearable patch antenna, aiming to provide a solution idea for the technical problem of poor flexibility of patch antennas in existing wearable applications.

[0005] To achieve the above purpose, the present invention provides a scale-shaped wearable patch antenna, which includes a metal radiation patch unit, a fabric dielectric board, a metal ground, and a coaxial feeding part. The metal radiation patch unit, the fabric dielectric board, and the metal ground are arranged in sequence from top to bottom. The metal radiation patch unit is cut into 20 pieces in the E-plane and H-plane directions, and is distributed in a stepped stack above the fabric dielectric board, and is supported on the upper surface of the fabric dielectric board by metal columns at the overlapping part of the units. The metal ground is fixedly connected to the fabric dielectric board and is attached to the lower surface of the fabric dielectric board. The probe part of the coaxial feeding part penetrates through the fabric dielectric board and is connected to a single unit of the topmost metal radiation patch unit. The penetration position is on one side of the center of the fabric dielectric board biased towards the X-axis direction, and the coaxial outer ground surface is connected to the metal ground located on the lower surface of the fabric dielectric board.

[0006] Among them, the metal radiation patch unit is set as a 4-layer structure with different heights. The first-layer metal radiation patch unit is arranged at the topmost. The second-layer metal radiation patch unit is adjacent to the E-plane of the first-layer metal radiation patch unit. The third-layer metal radiation patch unit is adjacent to the H-plane of the first-layer metal radiation patch unit. The fourth-layer metal radiation patch unit is arranged at the bottommost and is located on the upper surface of the fabric dielectric board.

[0007] Among them, the shape of the metal ground is rectangular, and the metal ground is fixedly connected to the outer surface grounding end of the coaxial feeding part.

[0008] Among them, the shape of the fabric dielectric board is consistent with that of the metal ground plane, the dielectric constant is 1.6, the loss tangent tanδ is 0.02, and the thickness of the fabric dielectric board is 1.5 mm.

[0009] Among them, the coaxial feeding part uses an SMA connector, the base size of the connector part is 6.5 mm * 6.5 mm, and the inner and outer radii of the corresponding coaxial cable are 0.5 and 1.15 mm respectively.

[0010] The present invention provides a scaly wearable patch antenna, which includes a metal radiation patch unit, a fabric dielectric board, a metal ground plane, and a coaxial feeding part. Among them, the metal radiation patch unit adopts a stepped stacked distribution. Each patch is cut along the E-plane and H-plane to form a multi-unit scaly metal arrangement structure. Twenty patch units are arranged in a four-layer structure in the order of H-plane first and then E-plane. A certain number of metal posts with the same radius are used in the overlapping area to connect the adjacent patch units on the E-plane and H-plane to ensure the formation of conduction current. By adjusting the size of each patch and the distance between the metal posts, impedance matching with a 50-ohm coaxial cable can be achieved, thus ensuring that the radiation characteristics are consistent with those of a traditional rectangular microstrip patch antenna. Compared with conventional similar patch antennas, the present invention is small in size, has better flexibility, and is more suitable for wearable antenna design. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0012] Figure 1 It is a three-dimensional structural schematic diagram of a scaly wearable patch antenna of the present invention.

[0013] Figure 2 It is a top view of a scaly wearable patch antenna of the present invention.

[0014] Figure 3 It is a front view of a scaly wearable patch antenna of the present invention.

[0015] Figure 4 It is a side view of a scaly wearable patch antenna of the present invention.

[0016] Figure 5 It is a schematic diagram of the reflection coefficient of a specific embodiment of the present invention compared with a traditional patch antenna.

[0017] Figure 6It is a schematic diagram of the current distribution in a specific embodiment of the present invention.

[0018] Figure 7 It is a schematic diagram of the E-plane gain pattern comparing a specific embodiment of the present invention with a traditional patch antenna.

[0019] Figure 8 It is a schematic diagram of the H-plane gain pattern comparing a specific embodiment of the present invention with a traditional patch antenna.

[0020] 1 - First-layer metal radiation patch unit, 2 - Second-layer metal radiation patch unit, 3 - Third-layer metal radiation patch unit, 4 - Fourth-layer metal radiation patch unit, 5 - Fabric dielectric board, 6 - Metal ground plane, 7 - Coaxial feeding part. Detailed implementation manners

[0021] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0022] Please refer to Figures 1 to 4 , the present invention provides a scale-shaped wearable patch antenna, including a metal radiation patch unit, a fabric dielectric board 5, a metal ground plane 6, and a coaxial feeding part 7. The metal radiation patch unit, the fabric dielectric board 5, and the metal ground plane 6 are arranged in sequence from top to bottom. The metal radiation patch unit is cut into 20 pieces in the E-plane and H-plane directions and is distributed in a stepped stacked manner above the fabric dielectric board 5, and is supported on the upper surface of the fabric dielectric board 5 by metal columns at the overlapping part of the units. The metal ground plane 6 is fixedly connected to the fabric dielectric board 5 and is attached to the lower surface of the fabric dielectric board 5. The coaxial feeding part 7 penetrates the fabric dielectric board 5 and is respectively connected to a single unit at the edge along the X-axis direction of the first-layer (uppermost layer) metal radiation patch unit, and the outer surface of the coaxial ground connection is connected to the metal ground plane 6 located on the lower surface of the fabric dielectric board 5.

[0023] The metal radiation patch unit is set as a 4-layer structure with different heights. The first-layer metal radiation patch unit 1 is arranged at the topmost. The second-layer metal radiation patch unit 2 is adjacent to the E-plane of the first-layer metal radiation patch unit 1. The third-layer metal radiation patch unit 3 is adjacent to the H-plane of the first-layer metal radiation patch unit 1. The fourth-layer metal radiation patch unit 4 is arranged at the bottommost and is located on the upper surface of the fabric dielectric board 5.

[0024] The shape of the metal ground plane 6 is rectangular, and the metal ground plane 6 is fixedly connected to the outer surface of the ground connection of the coaxial feeding part 7.

[0025] The shape of the fabric dielectric board 5 is consistent with that of the metal ground 6. The dielectric constant is 1.6, the loss tangent tanδ is 0.02, and the thickness of the fabric dielectric board 5 is 1.5 mm.

[0026] The coaxial feeding part 7 uses an SMA connector. The base size of the connector part is 6.5 mm * 6.5 mm, and the inner and outer radii of the corresponding coaxial cable are 0.5 and 1.15 mm respectively.

[0027] In this embodiment, the fabric dielectric board 5 is composed of pure cotton canvas material with a dielectric constant of 1.6. The thickness of the fabric dielectric board 5 is 1.5 mm. By adjusting the size of the patch unit and the metal posts in the overlapping area between the patch units, the radiation characteristics design of a traditional patch antenna is realized. The fourth-layer metal radiation patch unit 4 and the metal ground 6 are respectively attached to the upper and lower surfaces of the fabric dielectric board 5.

[0028] Further, please refer to Figures 5 to 8 , and the present invention is further illustrated by simulation experiments:

[0029] The following table shows the specific dimensions of each part of the scale-shaped wearable patch antenna in the specific embodiment.

[0030] parameter value parameter value parameter value <![CDATA[l1]]> 5.1 <![CDATA[l4]]> 6.62 <![CDATA[h3]]> 3 <![CDATA[w1]]> 5.1 <![CDATA[w4]]> 5.1 <![CDATA[g l > 0.5 <![CDATA[l2]]> 4.5 <![CDATA[w5]]> 5.1 <![CDATA[g w > 0.5 <![CDATA[w2]]> 5.1 h 1.5 <![CDATA[x p > 5.4 <![CDATA[l3]]> 4.5 <![CDATA[h1]]> 2 L 18.62 <![CDATA[w3]]> 5.1 <![CDATA[h2]]> 2.5 W 25.5

[0031] Figure 5 In the schematic diagram of the return loss of each part of the scale-shaped wearable patch antenna of the present invention in the frequency band, the shown frequency range is from 5.0 GHz to 6.5 GHz. Through Figure 5 It can be intuitively found that the curve has an obvious depression at 5.8 GHz, and its value is below -35 dB, indicating that the energy can leak out well at the corresponding frequency. The frequency band range is: 5.61 GHz - 6.02 GHz, the resonant frequency is 5.8 GHz, and the bandwidth is 410 MHz.

[0032] Figure 6 In the current distribution diagram of each part of the scale-shaped wearable patch antenna of the present invention at 5.8 GHz, the maximum current density of the proposed scale-shaped patch antenna is concentrated on the patch unit outside the H-plane. The probe feeds the current to the top-layer patch unit to form a TM10 mode, and then the metal posts conduct the current to each patch unit to ensure the performance of the antenna.

[0033] Figure 7 This is the comparison of the E-plane gain far-field radiation pattern of the scale-shaped wearable patch antenna of the present invention with that of a traditional patch antenna at the resonant frequency of 5.8 GHz.

[0034] Figure 8Comparison of the H-plane gain far-field radiation patterns between the flaky wearable patch antenna of the present invention and a conventional patch antenna at a resonant frequency of 5.8 GHz.

[0035] In summary, in the present invention, a certain number of metal posts with the same radius are used in the overlapping area between patch units to connect adjacent patch units on the E-plane and H-plane to ensure the generation of conduction current. At the same time, by adjusting the size of each patch unit and the spacing between metal posts, impedance matching with a 50-ohm coaxial cable can be achieved, ensuring that the current flow direction is the same as that of the conventional patch current, so that the radiation characteristics of the antenna are consistent with those of the conventional rectangular microstrip patch antenna. Through corresponding adjustments, the present invention provides an analysis idea for the technical problem of the deterioration of antenna performance caused by bending in the application field of patch antennas in the prior art.

[0036] The above-disclosed are only one or more preferred embodiments of the present invention. Of course, the scope of the rights of the present invention cannot be limited thereby. Those of ordinary skill in the art can understand all or part of the processes of implementing the above embodiments, and the equivalent changes made according to the claims of the present invention still fall within the scope covered by the invention.

Claims

1. A scaly wearable patch antenna, characterized in that: It includes a metal radiation patch unit, a fabric dielectric plate, a metal ground and a coaxial feeding part. The metal radiation patch unit, the fabric dielectric plate and the metal ground are arranged in sequence from top to bottom. The metal radiation patch unit is cut into 20 pieces in the E-plane and H-plane directions, and is distributed in a stepped stacking manner above the fabric dielectric plate, and is supported on the upper surface of the fabric dielectric plate by metal columns of the overlapping parts of the units. The metal ground is fixedly connected to the fabric dielectric plate and attached to the lower surface of the fabric dielectric plate. The probe part of the coaxial feeding part penetrates the fabric dielectric plate and is connected to a single unit of the uppermost metal radiation patch unit. The penetration position is located on the side of the center of the fabric dielectric plate deviating from the X-axis direction. The coaxial external ground surface is connected to the metal ground located on the lower surface of the fabric dielectric plate.

2. The scaly wearable patch antenna according to claim 1, characterized in that: The metal radiation patch units are arranged as a 4-layer structure with different heights, the first layer of metal radiation patch units are arranged at the top, the second layer of metal radiation patch units are adjacent to the E surface of the first layer of metal radiation patch units, the third layer of metal radiation patch units are adjacent to the H surface of the first layer of metal radiation patch units, and the fourth layer of metal radiation patch units are arranged at the bottom and located on the upper surface of the fabric dielectric plate.

3. The scaly wearable patch antenna according to claim 2, characterized in that: The metal ground is in a rectangular shape and is fixedly connected to the outer surface of the coaxial feeding part.

4. The scaly wearable patch antenna according to claim 3, characterized in that: The shape of the fabric dielectric plate is consistent with that of the metal ground, the dielectric constant is 1.6, the loss tangent tanδ is 0.02, and the thickness of the fabric dielectric plate is 1.5 mm.

5. The scaly wearable patch antenna according to claim 4, characterized in that: The coaxial feeding part uses an SMA connector, the base size of the connector part is 6.5mm*6.5mm, and the corresponding inner and outer radii of the coaxial line are 0.5 and 1.15 mm respectively.

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