Ultra wide band wearable antenna

Abstract

The invention, which relates to the technical field of the antenna, discloses an ultra-wideband wearable antenna comprising a dielectric substrate, a circular patch, a microstrip feeder line, two first grounding plates and a second grounding plate. The annular patch, the microstrip feeder line and the two first grounding plates are all arranged on the surface of one side of the dielectric substrate, and the second grounding plate is arranged on the surface of the other side of the dielectric substrate; one end of the micro-strip feeder line is connected with the bottom end of the annular patch, and the other end of the micro-strip feeder line is aligned with the bottom end of the dielectric substrate; the two first grounding plates are symmetrically arranged on the two sides of the microstrip feeder line, and the upper part of one side, far away from the microstrip feeder line, of each first grounding plate is provided with a cut corner; and an upper semicircular gap, two lower semicircular gaps, two inverted L-shaped gaps and two rectangular gaps are etched on the circular patch. According to the invention, the ultra-wideband characteristic under a full grounding layer structure can be realized.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and particularly to an ultra-wideband wearable antenna. Background Art

[0002] With the deep integration of Industry 4.0 and Internet of Things technologies, Cyber-Physical Systems (CPS) have achieved intelligent collaboration between physical devices and computing systems through wireless communication technologies. Among them, Wireless Body Area Network (WBAN), as the core communication architecture of wearable devices, has shown important value in fields such as medical monitoring and sports monitoring. Currently, the design of wearable antennas faces multiple technical challenges: it is necessary to overcome the interference of human tissues on electromagnetic characteristics on the basis of miniaturization and flexibility, and at the same time meet the requirements of Specific Absorption Rate (SAR) safety limits. In traditional solutions, although some grounding mechanisms can achieve low-profile bandwidth characteristics, the SAR suppression is insufficient. While Artificial Magnetic Conductor (AMC) and Electromagnetic Band Gap (EBG) structures can suppress backward radiation through a fully grounded layer, they have the defects of too high profile and limited bandwidth.

[0003] Ultra-wideband (UWB) technology provides an ideal short-range communication solution for WBAN with its high transmission rate and anti-interference ability in the 3.1 - 10.6 GHz frequency band. However, existing fully grounded layer UWB antennas are restricted by narrowband characteristics and it is difficult to balance broadband performance and human body safety; research shows that the high dielectric characteristics of human tissues will significantly change the antenna impedance matching state, resulting in a decrease in radiation efficiency and pattern distortion, and at the same time increasing the risk of electromagnetic wave absorption; the application of flexible substrates improves the wearing comfort, but exacerbates the dielectric loss and environmental impact sensitivity.

[0004] In view of the problems of the above-mentioned prior art, those skilled in the art urgently need an ultra-wideband wearable antenna to solve the deficiency of the existing fully grounded structure antenna in terms of bandwidth. Summary of the Invention

[0005] The purpose of the present invention is to provide an ultra-wideband wearable antenna to solve the problems existing in the above-mentioned prior art and to achieve ultra-wideband characteristics under a fully grounded layer structure.

[0006] To achieve the above purpose, the present invention provides the following solution:

[0007] The present invention provides an ultra-wideband wearable antenna, which includes a dielectric substrate, a circular patch, a microstrip feed line, two first ground planes and a second ground plane; the circular patch, the microstrip feed line and the two first ground planes are all arranged on one side surface of the dielectric substrate, and the second ground plane is arranged on the other side surface of the dielectric substrate; one end of the microstrip feed line is connected to the bottom end of the circular patch, and the other end is aligned with the bottom end of the dielectric substrate; the two first ground planes are symmetrically arranged on both sides of the microstrip feed line, and a chamfer is provided on the upper part of the side of the first ground plane away from the microstrip feed line; an upper semi-circular ring slot, two lower semi-circular ring slots, two inverted L-shaped slots and two rectangular slots are etched on the circular patch; the upper semi-circular ring slot is arranged on the upper half of the circular patch, and the bottom ends on both sides of the upper semi-circular ring slot are connected to one end of the corresponding lower semi-circular ring slot; the two rectangular slots are symmetrically arranged on the upper half of the circular patch; the two inverted L-shaped slots are symmetrically arranged on the lower half of the circular patch.

[0008] In some embodiments, the arc opening of the lower semi-circular ring slot faces the opposite direction to the arc opening of the upper semi-circular ring slot, and the inner diameter of the lower semi-circular ring slot is smaller than the inner diameter of the upper semi-circular ring slot; the inverted L-shaped slot includes a horizontal section and a vertical section, one end of the vertical section is perpendicularly connected to one end of the horizontal section, and the other end of the vertical section extends to the edge of the circular patch to form a first opening, and the other ends of the horizontal sections of the two inverted L-shaped slots extend in opposite directions; one end of the rectangular slot is connected to the upper semi-circular ring slot and the other end extends to the edge of the circular patch to form a second opening; the upper semi-circular ring slot, the two lower semi-circular ring slots, the two inverted L-shaped slots and the two rectangular slots are all symmetrically arranged with respect to the same diameter line of the circular patch.

[0009] In some embodiments, the dielectric substrate is made of a textile material, and the relative dielectric constant of the textile material is 1.72 and the loss tangent is 0.045; the length of the dielectric substrate is 80 mm, the width is 65 mm, and the thickness is 2 mm; the length of the second ground plane is equal to the length of the dielectric substrate, and the width of the second ground plane is equal to the width of the dielectric substrate.

[0010] In some embodiments, the outer radius of the circular patch is 19 mm and the inner radius is 5 mm.

[0011] In some embodiments, the center of the upper semi-circular ring slot is coaxially arranged with the center of the circular patch, and the inner radius of the upper semi-circular ring slot is 17 mm and the outer radius is 18 mm; the centers of the two lower semi-circular ring slots and the center of the circular patch are located on a straight line. One end of the lower semi-circular ring slot far from the center of the circular patch is connected to the bottom end of the upper semi-circular ring slot. The inner radius of the lower semi-circular ring slot is 4.3 mm and the outer radius is 5.3 mm.

[0012] In some embodiments, the lengths of the vertical section and the horizontal section of the inverted L-shaped slot are equal, and the distance between the vertical sections of the two inverted L-shaped slots is 9 mm. The slot width of the inverted L-shaped slot is 1 mm.

[0013] In some embodiments, the vertical distance from the top edge of the rectangular slot to the center of the circular patch is 12 mm, and the slot width of the rectangular slot is 1 mm.

[0014] In some embodiments, the width of the microstrip feed line is 3.48 mm and the length is 30 mm; the bottom end of the first ground plane is flush with the bottom end of the dielectric substrate, and one side end of the first ground plane far from the microstrip feed line is flush with the side end of the dielectric substrate. The distance between the other end of the first ground plane close to the microstrip feed line and the microstrip feed line is 0.5 mm, and the distance from the top end to the bottom end of the first ground plane is 29 mm; the chamfer is in a triangular structure, and the two right-angled sides of the triangular structure are equal and are 7 mm.

[0015] In some embodiments, the thickness dimensions of the circular patch, the microstrip feed line, the first ground plane, and the second ground plane are all 0.085 mm.

[0016] In some embodiments, the circular patch, the microstrip feed line, the first ground plane, and the second ground plane are all made of conductive cloth, and the surface resistance of the conductive cloth is less than 0.05 Ω / sq.

[0017] The present invention has achieved the following technical effects compared with the prior art:

[0018] The ultra-wideband wearable antenna of the present invention suppresses backward radiation by providing a second ground plane on one surface (i.e., the back surface) of the dielectric substrate, and this second ground plane is a full ground plane. Moreover, by providing a circular patch, a microstrip feed line, and two first ground planes on the other surface (i.e., the front surface) of the dielectric substrate, and simultaneously etching an upper semi-circular slot, two lower semi-circular slots, two inverted L-shaped slots, and two rectangular slots on the circular patch, the ultra-wideband characteristics under the full ground plane structure can be achieved. The present invention utilizes the inherent broadband characteristics of the circular planar monopole, improves the impedance mismatch caused by loading the full ground structure, and then broadens the bandwidth by introducing designs such as slots to stimulate multi-stage resonance of the antenna and introduce new resonance points; that is, the present invention can achieve the collaborative optimization of ultra-wideband characteristics and low SAR performance under the full ground plane structure. Description of the Drawings

[0019] 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 use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 Schematic three-dimensional structure diagram of the ultra-wideband wearable antenna in some embodiments of the present invention;

[0021] Figure 2 Front view of the ultra-wideband wearable antenna in some embodiments of the present invention;

[0022] Figure 3A Schematic diagram of a circular patch provided on the dielectric substrate in some embodiments of the present invention;

[0023] Figure 3B Schematic diagram of etching an upper semi-circular slot and a lower semi-circular slot on the circular patch in some embodiments of the present invention;

[0024] Figure 3C Schematic diagram of forming a circular patch on the circular patch in some embodiments of the present invention;

[0025] Figure 3D Schematic diagram of etching an inverted L-shaped slot on the circular patch in some embodiments of the present invention;

[0026] Figure 3E Schematic diagram of etching a rectangular slot on the circular patch in some embodiments of the present invention;

[0027] Figure 4 Reflection coefficient curve diagram of the ultra-wideband wearable antenna in some embodiments of the present invention;

[0028] Figure 5A The radiation pattern of the ultra-wideband wearable antenna in the x-z plane at 3.65 GHz for some embodiments of the present invention;

[0029] Figure 5B The radiation pattern of the ultra-wideband wearable antenna in the y-z plane at 3.65 GHz for some embodiments of the present invention;

[0030] Figure 6A The radiation pattern of the ultra-wideband wearable antenna in the x-z plane at 5.8 GHz for some embodiments of the present invention;

[0031] Figure 6B The radiation pattern of the ultra-wideband wearable antenna in the y-z plane at 5.8 GHz for some embodiments of the present invention;

[0032] Figure 7A The radiation pattern of the ultra-wideband wearable antenna in the x-z plane at 7.78 GHz for some embodiments of the present invention;

[0033] Figure 7B The radiation pattern of the ultra-wideband wearable antenna in the y-z plane at 7.78 GHz for some embodiments of the present invention;

[0034] Figure 8A The radiation pattern of the ultra-wideband wearable antenna in the x-z plane at 10.15 GHz for some embodiments of the present invention;

[0035] Figure 8B The radiation pattern of the ultra-wideband wearable antenna in the y-z plane at 10.15 GHz for some embodiments of the present invention.

[0036] In the figure: 1 - dielectric substrate; 2 - circular patch; 3 - microstrip feeder; 4 - first ground plane; 5 - upper semi-circular slot; 6 - lower semi-circular slot; 7 - inverted L-shaped slot; 8 - rectangular slot; 9 - chamfer. Detailed implementation manners

[0037] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0038] The purpose of the present invention is to provide an ultra-wideband wearable antenna to solve the problems existing in the above-mentioned prior art, and to achieve the collaborative optimization of the ultra-wideband characteristics and low SAR performance under the all-ground layer structure.

[0039] To make the above objects, features, and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0040] The present invention provides an ultra-wideband wearable antenna, as Figure 1 shown in FIGS. 5 to 8, including a dielectric substrate 1, a circular patch 2, a microstrip feed line 3, a first ground plane 4, and a second ground plane. Among them, the circular patch 2 is a radiation patch, the first ground plane 4 is a partial ground plane, and the second ground plane is a full ground plane.

[0041] As Figure 1 shown, in this embodiment, one side plane of the dielectric substrate 1 is defined as the xy plane. The length direction of the dielectric substrate 1 corresponds to the y direction, the width direction of the dielectric substrate 1 corresponds to the x direction, and the z direction is perpendicular to the xy plane; and it is defined that Figure 1 the direction indicated by the arrow in the y direction is upward, and the opposite direction of the direction indicated by the arrow in the y direction is downward.

[0042] One side surface of the dielectric substrate 1 is its front surface, and a circular patch 2, a microstrip feed line 3, and two first ground planes 4 are provided on the front surface of the dielectric substrate 1. One end of the microstrip feed line 3 is connected to the bottom end of the circular patch 2, and the other end of the microstrip feed line 3 is flush with the bottom end of the dielectric substrate 1; the two first ground planes 4 are symmetrically arranged on both sides of the microstrip feed line 3, and a cut-off corner 9 is provided on the upper part of the side of the first ground plane 4 away from the microstrip feed line 3; the other side surface of the dielectric substrate 1 is its back surface, and a second ground plane is provided on the back surface of the dielectric substrate 1, and the second ground plane has the same width and length as the dielectric substrate 1, realizing a full ground structure.

[0043] An upper semi-circular ring slot 5, two lower semi-circular ring slots 6, two inverted L-shaped slots 7, and two rectangular slots 8 are etched on the circular patch 2; among them, the upper half of the circular patch 2 is etched with an upper semi-circular ring slot 5, the center of the upper semi-circular ring slot 5 is coaxially arranged with the center of the circular patch 2, and the two bottom ends of the upper semi-circular ring slot 5 are respectively connected to one end of the two lower semi-circular ring slots 6.

[0044] The centers of the two lower semi-circular ring slots 6 and the center of the circular patch 2 are located on the same straight line, and the end of the lower semi-circular ring slot 6 away from the circular patch 2 is connected to the bottom end of the upper semi-circular ring slot 5; the arc-shaped opening of the lower semi-circular ring slot 6 is arranged upward, and the arc-shaped opening of the upper semi-circular ring slot 5 is arranged downward, that is, the arc-shaped openings of the lower semi-circular ring slot 6 and the upper semi-circular ring slot 5 face different directions; and the inner radius of the lower semi-circular ring slot 6 is smaller than the inner radius of the upper semi-circular ring slot 5.

[0045] Two inverted L-shaped slots 7 are symmetrically arranged in the lower half of the circular patch 2. The inverted L-shaped slot includes a vertical section and a horizontal section. One end of the vertical section is perpendicularly connected to one end of the horizontal section, and the other end of the vertical section extends to the edge of the circular patch 2 to form a first opening. The two vertical sections of the two inverted L-shaped slots 7 are arranged in parallel, and the other ends of the two horizontal sections of the two inverted L-shaped slots 7 extend in opposite directions to form closed ends.

[0046] Two rectangular slots 8 are symmetrically arranged in the upper half of the circular patch 2. One end of the rectangular slot 8 is connected to the upper half circular ring slot 5, and the other end extends to the edge of the circular patch 2 to form a second opening.

[0047] Moreover, the upper half circular ring slot 5, the two lower half circular ring slots 6, the two inverted L-shaped slots 7, and the two rectangular slots 8 of the present invention are all symmetrically arranged with respect to the same diameter line of the circular patch 2.

[0048] In some embodiments of the present invention, the dielectric substrate 1 is made of a textile material, and the relative dielectric constant of the textile material is 1.72, and the loss tangent is 0.045.

[0049] It should be noted that the dielectric substrate 1 can be made of jeans, or other synthetic materials with similar characteristic parameters such as relative dielectric constant and loss tangent; and the dielectric substrate 1 of the present invention can also be made of a flexible material such as felt, but the thickness of the dielectric substrate 1 needs to be adjusted according to the relative dielectric constant.

[0050] As Figure 2 described, the length L1 of the dielectric substrate 1 is 80 mm, the width W1 is 65 mm, and the thickness is 2 mm; the length and width of the second ground plane are respectively equal to the length and width of the dielectric substrate 1.

[0051] In some embodiments of the present invention, the outer radius R1 of the circular patch 2 is 19 mm and its inner radius dimension R3 is 4.5 mm.

[0052] In some embodiments of the present invention, the inner radius R2 of the upper half circular ring slot 5 is 17 mm and the outer radius is 18 mm, that is, the slot width of the upper half circular ring slot 5 is 1 mm.

[0053] The centers of the two lower half circular ring slots 6 are located on a straight line with the center of the circular patch 2, and one end of the lower half circular ring slot 6 far from the center of the circular patch 2 is correspondingly connected to the bottom end of the upper half circular ring slot 5, and the other end of the lower half circular ring slot 6 close to the center of the circular patch 2 is a closed end; the inner radius R4 of the lower half circular ring slot 6 is 4.3 mm and the outer radius is 5.3 mm, that is, the slot width of the lower half circular ring slot 6 is 1 mm.

[0054] It should be noted that the central angles corresponding to both ends of the upper semi-circular ring gap 5 of the present invention are 180 degrees, that is, the upper semi-circular ring gap 5 is half of the corresponding entire ring; the central angle corresponding to both ends of the lower semi-circular ring gap 6 is 180 degrees, that is, the lower semi-circular ring gap 6 is half of the corresponding entire ring.

[0055] In some embodiments of the present invention, the length y1 of the vertical section of the inverted L-shaped gap 7 is 7 mm, and the length L2 of the horizontal section is 7 mm; the two vertical sections of the two inverted L-shaped gaps 7 are arranged along the length direction of the circular patch 2 and the distance X1 between them is 9 mm, and the slot width S3 of the two inverted L-shaped gaps 7 is 1 mm.

[0056] In some embodiments of the present invention, the rectangular gap 8 is arranged along the width direction of the circular patch 2, and the vertical distance y2 from the top edge of the rectangular gap 8 to the center of the circular patch 2 is 12 mm, and the slot width S2 of the rectangular gap 8 is 1 mm.

[0057] In some embodiments of the present invention, the width W2 of the microstrip feed line 3 is 3.48 mm, and the length L4 is 30 mm.

[0058] The bottom end of the first ground plane 4 is flush with the bottom end of the dielectric substrate 1, and the side end of the first ground plane 4 away from the microstrip feed line 3 is flush with the side end of the dielectric substrate 1. The distance S1 between the other end of the first ground plane 4 close to the microstrip feed line 3 and the microstrip feed line 3 is 0.5 mm, and the distance L3 from the top end to the bottom end of the first ground plane 4 is 29 mm; the chamfer 9 of the first ground plane 4 has a triangular structure, and the dimensions of the two right-angled sides of this triangular structure are a and b respectively, and both a and b are 7 mm.

[0059] In some embodiments of the present invention, the thickness dimensions of the circular patch 2, the microstrip feed line 3, the first ground plane 4 and the second ground plane are all 0.085 mm.

[0060] It should be noted that the above-mentioned various dimensions of the embodiments of the present invention are described by taking fixed values as examples. Those skilled in the art can also set each dimension within a certain range. For example, each dimension can be in the range of the fixed value ±(1% - 4%), and the present invention does not make specific limitations.

[0061] In some embodiments of the present invention, the circular patch 2, the microstrip feed line 3, the first ground plane 4 and the second ground plane are all made of conductive cloth, and the surface resistance of this conductive cloth is less than 0.05 Ω / sq; specifically, this conductive cloth can be copper-nickel plated flexible plain polyester material or other conductive fabrics.

[0062] As Figures 3A to 3E shown, the circular patch 2 of the present invention has been optimized and designed through the following process:

[0063] Figure 3A A circular patch is disposed on the dielectric substrate 1;

[0064] Figure 3B An upper semi-circular ring slot 5 and two lower semi-circular ring slots 6 are etched on the circular patch;

[0065] Figure 3C A small circular patch is cut off from the middle of the circular patch to form an annular patch 2;

[0066] Figure 3D Two symmetrically arranged inverted L-shaped slots 7 are etched on the lower half of the annular patch 2;

[0067] Figure 3E Two symmetrically arranged rectangular slots 8 are etched on the upper half of the annular patch 2.

[0068] As Figure 4 shown in the reflection coefficient curve graph of the ultra-wideband wearable antenna of the present invention, it can be seen that the operating frequency bands of the antenna of the present invention below -10 dB are 3.16 - 3.83 GHz and 4.9 - 10.4 GHz respectively; that is, in terms of impedance matching, the antenna achieves coverage of the frequency bands of 3.16 - 3.83 GHz and 4.9 - 10.4 GHz, broadening the bandwidth.

[0069] And representative frequency points on the reflection coefficient curve are selected: 3.65 GHz, 5.8 GHz, 7.78 GHz, and 10.15 GHz, and their radiation patterns are shown in FIGS. 5 to 8; among them, the radiation pattern at the 3.65 GHz frequency point is as Figure 5A and Figure 5B shown, the radiation pattern at the 5.8 GHz frequency point is as Figure 6A and Figure 6B shown, the radiation pattern at the 7.78 GHz frequency point is as Figure 7A and Figure 7B shown, the radiation pattern at the 10.15 GHz frequency point is as Figure 8A and Figure 8B shown.

[0070] It can be known from the radiation patterns in FIGS. 5 to 8 that the radiation patterns exhibit good unidirectional radiation characteristics, that is, it indicates that the back radiation of the antenna is significantly suppressed; and the maximum gain reaches 7.61 dBi at 10.15 GHz.

[0071] Combining the above working bandwidth and the far-field effect of the antenna, it can be found that the present invention effectively suppresses the back radiation of the antenna on the basis of realizing ultra-wideband, and has stable operation, meeting the requirements of the WBAN working scenario. And the antenna selects a textile material as the dielectric substrate 1, which has low cost, good flexibility, good air permeability and is easy to integrate with clothing.

[0072] The main design principle of the present invention is to utilize the inherent broadband characteristics of the circular planar monopole, improve the impedance mismatch caused by loading the full-ground structure, and then stimulate the multi-stage resonance of the antenna and introduce new resonance points to broaden the bandwidth by introducing slits or loading parasitic patches, etc. The introduction of the full-ground is mainly to suppress the backward radiation of the antenna, improve the ability of the antenna to resist the near-field perturbation of the human body while reducing the impact of the antenna radiation on human health, and achieve the isolation of the human-antenna system.

[0073] Specific examples are applied in the present invention to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, there will be changes in the specific implementation manner and application scope according to the idea of the present invention. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A ultra-wideband wearable antenna, characterized in that, It includes a dielectric substrate, a circular patch, a microstrip feeder, two first ground planes, and a second ground plane; The circular patch, the microstrip feeder, and the two first ground planes are all disposed on one side surface of the dielectric substrate, and the second ground plane is disposed on the other side surface of the dielectric substrate; One end of the microstrip feeder is connected to the bottom end of the circular patch, and the other end is aligned with the bottom end of the dielectric substrate; the two first ground planes are symmetrically disposed on both sides of the microstrip feeder, and a chamfer is provided at the upper part of the side of the first ground plane away from the microstrip feeder; An upper semi-circular ring slot, two lower semi-circular ring slots, two inverted L-shaped slots, and two rectangular slots are etched on the circular patch; the upper semi-circular ring slot is disposed in the upper half of the circular patch, and the bottom ends on both sides of the upper semi-circular ring slot are connected to one end of the corresponding lower semi-circular ring slot; the two rectangular slots are symmetrically disposed in the upper half of the circular patch; the two inverted L-shaped slots are symmetrically disposed in the lower half of the circular patch.

2. The ultra-wideband wearable antenna according to claim 1, characterized in that The arc opening of the lower semi-circular ring slot faces the opposite direction to the arc opening of the upper semi-circular ring slot, and the inner diameter of the lower semi-circular ring slot is smaller than the inner diameter of the upper semi-circular ring slot; The inverted L-shaped slot includes a horizontal section and a vertical section, one end of the vertical section is perpendicularly connected to one end of the horizontal section, and the other end of the vertical section extends to the edge of the circular patch to form a first opening, and the other ends of the horizontal sections of the two inverted L-shaped slots extend in opposite directions; One end of the rectangular slot is connected to the upper semi-circular ring slot and the other end extends to the edge of the circular patch to form a second opening; The upper semi-circular ring slot, the two lower semi-circular ring slots, the two inverted L-shaped slots, and the two rectangular slots are all symmetrically arranged with respect to the same diameter line of the circular patch.

3. The ultra-wideband wearable antenna according to claim 1, wherein, The dielectric substrate is made of a textile material, and the relative dielectric constant of the textile material is 1.72, and the tangent of the loss angle is 0.045; The length of the dielectric substrate is 80 mm, the width is 65 mm, and the thickness is 2 mm; the length of the second ground plane is equal to the length of the dielectric substrate, and the width of the second ground plane is equal to the width of the dielectric substrate.

4. The ultra-wideband wearable antenna according to claim 1, characterized in that, The outer radius of the circular patch is 19 mm and the inner radius is 5 mm.

5. The ultra-wideband wearable antenna according to claim 2, characterized in that, The center of the upper semi-circular ring slot is coaxially arranged with the center of the circular patch, and the inner radius of the upper semi-circular ring slot is 17 mm and the outer radius is 18 mm; The centers of the two lower semi-circular ring slots are located on a straight line with the center of the circular patch, one end of the lower semi-circular ring slot away from the center of the circular patch is connected to the bottom end of the upper semi-circular ring slot, and the inner radius of the lower semi-circular ring slot is 4.3 mm and the outer radius is 5.3 mm.

6. The ultra-wideband wearable antenna according to claim 2, wherein, The lengths of the vertical section and the horizontal section of the inverted L-shaped slot are equal, and the distance between the vertical sections of the two inverted L-shaped slots is 9 mm, and the slot width of the inverted L-shaped slot is 1 mm.

7. The ultra-wideband wearable antenna according to claim 2, characterized in that, The vertical distance between the top edge of the rectangular slot and the center of the circular patch is 12 mm, and the slot width of the rectangular slot is 1 mm.

8. The ultra-wideband wearable antenna according to claim 1, characterized in that The width of the microstrip feed line is 3.48 mm and the length is 30 mm; The bottom end of the first ground plane is flush with the bottom end of the dielectric substrate, and one side end of the first ground plane away from the microstrip feed line is flush with the side end of the dielectric substrate. The distance between the other end of the first ground plane close to the microstrip feed line and the microstrip feed line is 0.5 mm, and the distance from the top end to the bottom end of the first ground plane is 29 mm; The chamfer is in a triangular structure, and the two right-angled sides of the triangular structure are equal and are 7 mm.

9. The ultra-wideband wearable antenna according to claim 1, characterized in that, The thickness dimensions of the circular patch, the microstrip feed line, the first ground plane and the second ground plane are all 0.085 mm.

10. The ultra-wideband wearable antenna according to claim 1, characterized in that, The circular patch, the microstrip feed line, the first ground plane and the second ground plane are all made of conductive cloth, and the surface resistance of the conductive cloth is less than 0.05 Ω / sq.

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