A three-frequency antenna based on artificial magnetic conductor structure and a wearable device

Abstract

The utility model discloses a three frequency antenna and wearable equipment based on artificial magnetic conductor structure relates to antenna technical field. Three frequency antenna includes antenna radiation unit, magnetic conductor array reflection board and the air layer between both; Antenna radiation unit includes antenna radiation patch; Antenna radiation patch includes first bow type patch, second bow type patch and first extension patch; Magnetic conductor array reflection board includes n x m periodic arrangement's magnetic conductor unit; Magnetic conductor unit includes reflection medium substrate, reflection radiation patch and radiating backboard; Reflection radiation patch includes first reflection patch, second reflection patch and third reflection patch; Second reflection patch is located in the first hollow structure of first reflection patch; Third reflection patch is located in the second hollow structure of second reflection patch; Third reflection patch includes third hollow structure. The utility model improves three frequency antenna in three frequency band's radiation gain, has reduced three frequency antenna in three frequency band's back radiation.

Description

Technical Field

[0001] This utility model relates to the field of antenna technology, and in particular to a tri-band antenna based on an artificial magnetic conductor structure and a wearable device. Background Technology

[0002] With the rapid development of smart healthcare, sports and health, wireless body area networks (BNBs), and the Internet of Things (IoT), wearable devices are increasingly demanding multi-band wireless communication. Especially in body-worn applications, antennas need to support multiple operating frequency bands simultaneously to balance data transmission rates, coverage, and protocol compatibility. Among these, 3.5GHz, as a crucial component of the 5G mid-band, is suitable for wide-area, low-latency transmission; the 5.8GHz band is an open ISM band, compatible with high-speed short-range communication protocols such as Wi-Fi and WLAN; and the 7GHz band is a key candidate frequency for future high-speed data links and expanded body area networks, enabling parallel collaboration between low-power monitoring and big data interaction. Therefore, developing tri-band antennas capable of simultaneously covering 3.5GHz, 5.8GHz, and 7GHz is of great significance for improving the overall communication capabilities of wearable terminals.

[0003] Existing wearable antennas typically employ a design combining an antenna radiating element and an artificial magnetic conductor structure reflector. The artificial magnetic conductor array reflector achieves zero-phase reflection at the target frequency, effectively suppressing back radiation from the antenna radiating element and reducing near-field coupling between the antenna radiating element and the human body, thereby reducing the specific absorption rate (SAR) and improving radiation gain. However, current wearable antenna designs are generally optimized only for single or dual frequencies, making it difficult to achieve simultaneous tuning control at three different frequencies. Furthermore, under flexible media conditions, their frequency response is prone to shift with structural deformation. In addition, existing solutions often employ separate designs for the antenna radiating element and the artificial magnetic conductor structure reflector, lacking a coordinated alignment mechanism between resonant points, resulting in insufficient overall electromagnetic performance matching. Utility Model Content

[0004] This invention provides a tri-band antenna and wearable device based on an artificial magnetic conductor structure. By setting antenna radiating patches and reflective radiating patches as a preset structure, the back radiation of the tri-band antenna in the three frequency bands is suppressed and its radiation gain in the three frequency bands is improved.

[0005] The first aspect of this utility model provides a tri-band antenna based on an artificial magnetic conductor structure, the tri-band antenna based on an artificial magnetic conductor structure includes: an antenna radiating element, a magnetic conductor array reflector, and an air layer; The antenna radiating element includes an antenna dielectric substrate and an antenna radiating patch attached to the antenna dielectric substrate; the antenna radiating patch includes at least a first bow-shaped patch, a second bow-shaped patch, and a first extension patch; the first bow-shaped patch and the second bow-shaped patch are disposed opposite to each other along a first direction and are connected to each other; the first extension patch is located between the first bow-shaped patch and the second bow-shaped patch, and is connected to both the first bow-shaped patch and the second bow-shaped patch; The magnetic conductor array reflector comprises n×m periodically arranged magnetic conductor units; n is a positive integer greater than or equal to 2, and m is a positive integer greater than or equal to 2. The magnetic conductor unit includes a reflective dielectric substrate, a reflective radiation patch attached to one side of the reflective dielectric substrate, and a radiation backplate attached to the side of the reflective dielectric substrate opposite to the reflective radiation patch; the reflective radiation patch includes a first reflective patch, a second reflective patch, and a third reflective patch spaced apart; the first reflective patch includes a first cutout structure; the second reflective patch is located within the first cutout structure and includes a second cutout structure; the third reflective patch is located within the second cutout structure and includes a third cutout structure. The air layer is located between the antenna radiating element and the magnetic conductor array reflector, and the antenna dielectric substrate is located on the side of the air layer away from the reflective radiating patch.

[0006] Optionally, the first reflective patch includes a first sub-reflective patch, a second sub-reflective patch, a third sub-reflective patch, and a fourth sub-reflective patch, which are respectively located at the four corners of the reflective medium substrate and spaced apart. The outer contours of the first sub-reflective patch, the second sub-reflective patch, the third sub-reflective patch, and the fourth sub-reflective patch all include two right-angled sides arranged perpendicularly to each other and rounded edges connected to the two right-angled sides respectively.

[0007] Optionally, the second reflective patch is annular in shape; The center point of the second reflective patch coincides with that of the first hollow structure.

[0008] Optionally, the outer contour of the third reflective patch is circular; the shape of the third hollow structure is a combination of a first sub-hollow structure and a second sub-hollow structure, both of which are rounded rectangles. The center points of the first sub-hollow structure and the second sub-hollow structure coincide, and the first sub-hollow structure and the second sub-hollow structure are set perpendicular to each other.

[0009] Optionally, the antenna radiating element further includes a main feed line attached to the antenna dielectric substrate, and a first ground feed line and a second ground feed line located on opposite sides of the main feed line; One end of the main feeder is connected to the bottom extension end of the first bow-shaped patch and the bottom extension end of the second bow-shaped patch, respectively.

[0010] Optionally, the antenna radiating patch further includes a second extension patch; The second extension patch is connected between the main feed line and the bottom extension end of the first bow-shaped patch and the bottom extension end of the second bow-shaped patch.

[0011] Optionally, the longitudinal length L of the antenna dielectric substrate is in the range of 0.266λ0 < L < 0.327λ0; The width W of the antenna dielectric substrate in the lateral direction ranges as follows: 0.175λ0 < W < 0.222λ0; The length L1 of the first extension patch along the longitudinal direction ranges from 0.064λ0 to L1 to 0.076λ0. The width Ws of the reflective medium substrate in the transverse direction ranges as follows: 0.287λ0 < Ws < 0.333λ0; The width W1 of the first reflective patch in the lateral direction ranges from 0.278λ0 to W1 to 0.298λ0. λ0 is the wavelength in free space.

[0012] Optionally, the radius r1 of the second reflective patch can be in the range of 0.11λ0 < r1 < 0.119λ0; The radius r2 of the second hollow structure has a range of values: 0.091λ0 < r2 < 0.103λ0; λ0 is the wavelength in free space.

[0013] Optionally, the width W5 of the second extension patch in the lateral direction is in the range of: 0.053λ0 < W5 < 0.084λ0; λ0 is the wavelength in free space.

[0014] The second aspect of this utility model provides a wearable device, which includes a tri-band antenna based on an artificial magnetic conductor structure as described above.

[0015] The technical solution of this utility model enhances the resonant stability of a tri-band antenna by incorporating an antenna radiating element, a magnetic conductor array reflector, and an air layer in a tri-band antenna based on an artificial magnetic conductor structure. This is achieved by placing the air layer between the antenna radiating element and the magnetic conductor array reflector, and placing the antenna dielectric substrate on the side of the air layer away from the reflective radiating patch. The antenna radiating element incorporates an antenna dielectric substrate and an antenna radiating patch attached to it. Furthermore, the antenna radiating patch includes a first bow-shaped patch, a second bow-shaped patch, and a first extension patch, which extends the current path within the antenna radiating patch and introduces additional resonant modes, thereby enabling tri-band radiation. Finally, the magnetic conductor array reflector incorporates n×m periodically arranged magnetic conductor elements, achieving zero-phase reflection through the coordinated operation of these multiple magnetic conductor elements. By incorporating a reflective dielectric substrate, reflective radiation patches, and a radiation backplate on opposite sides of the reflective dielectric substrate within a magnetic conductor unit, and by arranging a first, second, and third reflective patch at intervals within the reflective radiation patches, with the second reflective patch positioned within a first hollow structure in the first reflective patch, the third reflective patch positioned within a second hollow structure in the second reflective patch, and a third hollow structure within the third reflective patch, the first, second, and third reflective patches can respectively form an outer ring oscillation circuit, a middle ring oscillation circuit, and an inner ring oscillation circuit. These oscillation circuits can achieve spatial coupling, thereby enabling the magnetic conductor array reflector to suppress back radiation and improve the actual gain of tri-band radiation. Furthermore, the magnetic conductor array reflector can reduce near-field coupling between electromagnetic waves and the human body, effectively reducing electromagnetic wave penetration into the body. By optimizing the radiation gain and safety of the tri-band antenna, the communication reliability, battery life, and wearing comfort of wearable devices are significantly improved.

[0016] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a three-band antenna based on an artificial magnetic conductor structure provided in an embodiment of this utility model; Figure 2 This is a schematic diagram of the structure of a magnetic conductor array unit provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of an antenna radiating unit provided in an embodiment of this utility model; Figure 4 This is a schematic diagram of another antenna radiating element provided in this embodiment of the present invention; Figure 5 This is a schematic diagram of another magnetic conductor array reflector provided in this embodiment of the present invention; Figure 6 A schematic diagram of the reflection characteristic curve of the magnetic conductor array reflector provided in this embodiment of the utility model; Figure 7 A schematic diagram of the structure showing the influence curves of electromagnetic waves with different polarization angles on the reflection characteristics of a magnetic conductor array reflector, provided for embodiments of this utility model; Figure 8 A schematic diagram of the effect curve of the rotation of the magnetic conductor array reflector structure on the reflection phase provided in an embodiment of this utility model; Figure 9 A schematic diagram of the equivalent circuit of the magnetic conductor array reflector provided in this embodiment of the utility model; Figure 10 A schematic diagram of the reflection phase curve of the equivalent circuit of the magnetic conductor array reflector provided in this embodiment of the utility model; Figure 11 A schematic diagram of the reflection coefficient curves of the antenna radiating element before and after loading the magnetic conductor array reflector, provided for an embodiment of this utility model; Figure 12 A schematic diagram of the reflection coefficient curves of a tri-band antenna based on an artificial magnetic conductor structure provided in this embodiment of the utility model under different bending directions and bending radii; Figure 13 Far-field radiation pattern of a three-band antenna based on an artificial magnetic conductor structure provided in this embodiment of the present invention; Figure 14 Simulated three-dimensional far-field radiation map of a three-band antenna based on an artificial magnetic conductor structure provided for embodiments of this utility model; Figure 15 The simulation results of the specific absorption rate of the tri-band antenna based on the artificial magnetic conductor structure provided for the embodiment of this utility model under conditions close to the human body model are shown in the figure. Figure 16 Measured far-field radiation pattern of a tri-band antenna based on an artificial magnetic conductor structure when bent along the x-axis under different bending radii, as provided in this embodiment of the utility model. Figure 17The measured far-field radiation pattern of the tri-band antenna based on the artificial magnetic conductor structure provided in this embodiment of the invention when bent along the y-axis under different bending radii. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] Figure 1 This is a schematic diagram of a three-band antenna based on an artificial magnetic conductor structure provided by an embodiment of this utility model. Figure 1As shown, the tri-band antenna based on an artificial magnetic conductor structure includes: an antenna radiating element 1, a magnetic conductor array reflector 2, and an air layer; the antenna radiating element 1 includes an antenna dielectric substrate 11 and an antenna radiating patch 12 attached to the antenna dielectric substrate 11; the antenna radiating patch 12 includes at least a first bow-shaped patch 121, a second bow-shaped patch 122, and a first extension patch 123; the first bow-shaped patch 121 and the second bow-shaped patch 122 are arranged opposite to each other along a first direction and are connected to each other; the first extension patch 123 is located between the first bow-shaped patch 121 and the second bow-shaped patch 122, and is connected to both the first bow-shaped patch 121 and the second bow-shaped patch 122; the magnetic conductor array reflector 2 includes n×m periodically arranged magnetic conductor elements 21; n is a positive integer greater than or equal to 2, and m is a positive integer greater than or equal to 2; the magnetic conductor array reflector 2 includes n×m periodically arranged magnetic conductor elements 21; n is a positive integer greater than or equal to 2, and m is a positive integer greater than or equal to 2; the magnetic conductor array reflector 2 includes an antenna dielectric substrate 11 and an antenna radiating patch 122. The conductor unit 21 includes a reflective dielectric substrate 22, a reflective radiation patch 23 attached to one side of the reflective dielectric substrate 22, and a radiation backplate attached to the side of the reflective dielectric substrate 22 away from the reflective radiation patch 23. The reflective radiation patch 23 includes a first reflective patch 201, a second reflective patch 202, and a third reflective patch 203 spaced apart. The first reflective patch 201 includes a first cutout structure 204. The second reflective patch 202 is located within the first cutout structure 204 and includes a second cutout structure 205. The third reflective patch 203 is located within the second cutout structure 205 and includes a third cutout structure 206. An air layer is located between the antenna radiation unit 1 and the magnetic conductor array reflector 2, and the antenna dielectric substrate 11 is located on the side of the air layer away from the reflective radiation patch 23.

[0022] Specifically, the antenna radiating element 1 is used to receive frequency signals output by the wireless communication module of wearable devices, such as smartwatches or medical testing equipment, for example, three-frequency signals of 3.5GHz, 5.8GHz, and 7GHz. It can convert electrical signals into electromagnetic waves and radiate them outwards through the antenna radiating patch 12, thereby ensuring stable wireless communication between the wearable device and external devices. The magnetic conductor array reflector 2 is used to achieve zero-phase reflection at target frequencies, such as 3.5GHz, 5.8GHz, and 7GHz, through its periodically arranged magnetic conductor elements 21. This means the reflected electromagnetic waves are in phase with the incident electromagnetic waves, thus concentrating the electromagnetic waves radiated by the antenna radiating element 1 in the forward direction, suppressing back radiation, and reducing near-field coupling between the electromagnetic waves and the human body. An air layer is disposed between the antenna radiating element 1 and the magnetic conductor array reflector 2, and the antenna dielectric substrate 11 is located on the side of the air layer away from the reflective radiating patch 23. This allows the air layer to provide an appropriate spacing between the wireless radiating element 1 and the magnetic conductor array reflector 2, thereby enhancing the resonance stability of the tri-band antenna in the three frequency bands. At the same time, it avoids the magnetic conductor array reflector 2 being directly affected by the antenna radiating element 1, thus improving the durability of the tri-band antenna.

[0023] Specifically, the antenna radiating element 1 includes an antenna dielectric substrate 11 and an antenna radiating patch 12 attached to the antenna dielectric substrate 11. The antenna dielectric substrate 11 can be made of flexible dielectric polydimethylsiloxane (PDMS) material. PDMS has a dielectric constant of 2.75 and possesses flexibility, transparency, good mechanical stability, and excellent biocompatibility, meeting the needs of wearable applications. The thickness of the antenna dielectric substrate 11 can be 1.5 mm. The antenna radiating patch 12 can be made of conductive cloth and attached to the surface of the antenna dielectric substrate 11, thereby forming a highly efficient radiator. The antenna radiating patch 12 includes at least a first bow-shaped patch 121, a second bow-shaped patch 122, and a first extension patch 123. The first bow-shaped patch 121 and the second bow-shaped patch 122 are arranged opposite to each other and connected along a first direction, which can be a transverse direction. Specifically, the top extension ends of the first bow-shaped patch 121 and the second bow-shaped patch 122 are connected, as are the bottom extension ends of the first bow-shaped patch 121 and the second bow-shaped patch 122, thereby forming a continuous conductive channel. This allows the tri-band antenna to achieve dual-band resonance. The first bow-shaped patch 121 and the second bow-shaped patch 122 have the same shape. Between the top and bottom extension ends of the first bow-shaped patch 121, there may be a first straight section, a second straight section, a third straight section, a fourth straight section, and a fifth straight section connected sequentially. The first, second, and fifth straight sections extend longitudinally, while the second and fourth straight sections extend transversely.

[0024] The first extension patch 123 is located between the first bow-shaped patch 121 and the second bow-shaped patch 122, and is connected to both. For example, the first extension patch 123 can be connected to the bottom extension end of the first bow-shaped patch 121 and the bottom extension end of the second bow-shaped patch 122, respectively, to extend the current path and introduce additional resonant modes, enabling the tri-band antenna to achieve tri-band resonance. Simultaneously, the combined structure of the first bow-shaped patch 121, the second bow-shaped patch 122, and the first extension patch 123, while maintaining geometric symmetry, increases the diversity of current distribution and distributed capacitance effect, thereby achieving stable multi-band resonance and improving impedance matching performance.

[0025] The magnetic conductor array reflector 2 comprises n×m periodically arranged magnetic conductor units 21, where n is a positive integer greater than or equal to 2 and m is a positive integer greater than or equal to 2. This allows the magnetic conductor array reflector 2 to achieve zero-phase reflection at target frequencies, such as 3.5GHz, 5.8GHz, and 7GHz, through the coordinated operation of multiple magnetic conductor units 21. This concentrates the electromagnetic waves radiated by the antenna radiating unit 1 in the forward direction and suppresses back radiation. Unless otherwise specified, the embodiments of this utility model use a magnetic conductor array reflector 2 comprising 2×2 periodically arranged magnetic conductor units 21 as an example to illustrate the technical solution of this utility model. The magnetic conductor unit 21 includes a reflective dielectric substrate 22, a reflective radiation patch 23 attached above the reflective dielectric substrate 22, and a radiation backplate attached below the reflective dielectric substrate 22. The reflective dielectric substrate 22 can be made of PDMS material, and the reflective radiation patch 23 and radiation backplate can be made of conductive cloth and are respectively attached to the upper and lower surfaces of the reflective dielectric substrate 22. When the electromagnetic wave radiated by the antenna radiation unit 1 is incident, the electric and magnetic fields between the reflective radiation patch 23 and the radiation backplate interact, thereby generating resonant oscillations similar to an LC oscillating circuit, laying the foundation for achieving zero-phase reflection through the magnetic conductor array reflector 2. The thickness of the reflective dielectric substrate 22 can be 2.5 mm.

[0026] The reflective radiation patch 23 includes a first reflective patch 201, a second reflective patch 202, and a third reflective patch 203 spaced apart. The first reflective patch 201 includes a first hollow structure 204 to form an outer ring oscillation circuit, thereby achieving zero-phase reflection at 5.8 GHz. The second reflective patch 202 is located within the first hollow structure 204 and includes a second hollow structure 205 to form a middle ring oscillation circuit, thereby achieving zero-phase reflection at 3.5 GHz. The third reflective patch 203 is located within the second hollow structure 205 and includes a third hollow structure 206 to form an inner ring oscillation circuit, thereby achieving zero-phase reflection at 7 GHz. Simultaneously, the electromagnetic fields generated by the outer ring oscillation circuit, the middle ring oscillation circuit, and the inner ring oscillation circuit can generate a coupling effect, mutually modulating the resonant frequencies to achieve stable zero-phase reflection of the magnetic conductor array reflector 2 at the three frequency points. This ensures that the reflected electromagnetic wave is in phase with the incident electromagnetic wave, thereby significantly improving directivity and forward gain within the target frequency band. Furthermore, the flexible characteristics of the PDMS reflective substrate 22 further enhance the stability of the magnetic conductor array reflector 2 under bending conditions.

[0027] Compared to traditional wearable antennas that can only optimize for a single frequency, this tri-band antenna, by setting the antenna radiating patch 12 in a pre-defined structure, can achieve tri-band resonance at 3.5GHz, 5.8GHz, and 7GHz. This significantly reduces the reflection coefficient of the tri-band antenna in all three frequency bands, reduces energy loss, and improves the radiation gain of the tri-band antenna in all three bands. Simultaneously, by setting the reflective radiating patch 23 in the tri-band antenna in a pre-defined structure, zero-phase reflection can be achieved at target frequencies, such as 3.5GHz, 5.8GHz, and 7GHz. This allows the electromagnetic waves radiated by the antenna radiating element 1 to be concentrated in the forward direction and suppress back radiation through the magnetic conductor array reflector 2, thereby improving the actual radiation gain in all three frequency bands. Furthermore, the magnetic conductor array reflector 2 can also reduce the near-field coupling between electromagnetic waves and the human body, effectively reducing the penetration of electromagnetic waves into the human body, ensuring that the SAR value is controlled within safe limits, and protecting human safety. By setting an antenna radiating element 1 and a magnetic conductor array reflector 2 in the tri-band antenna, the structural compactness of the tri-band antenna is improved, the radiation gain and security of the tri-band antenna in the three frequency bands are optimized, and the communication reliability, battery life and wearing comfort of the wearable device are significantly improved, enabling the wearable device to adapt to a variety of application scenarios.

[0028] In this embodiment, the resonant stability of the tri-band antenna is enhanced by incorporating an antenna radiating element, a magnetic conductor array reflector, and an air layer in a tri-band antenna based on an artificial magnetic conductor structure. The air layer is positioned between the antenna radiating element and the magnetic conductor array reflector, and the antenna dielectric substrate is positioned on the side of the air layer away from the reflective radiating patch. The antenna radiating element contains an antenna dielectric substrate and an antenna radiating patch attached to it. The antenna radiating patch includes a first bow-shaped patch, a second bow-shaped patch, and a first extension patch, which extends the current path in the antenna radiating patch and introduces additional resonant modes, thereby enabling the antenna radiating patch to radiate in all three frequency bands. The magnetic conductor array reflector contains n×m periodically arranged magnetic conductor elements, achieving zero-phase reflection through the coordinated operation of multiple magnetic conductor elements. By incorporating a reflective dielectric substrate, reflective radiation patches, and a radiation backplate on opposite sides of the reflective dielectric substrate within a magnetic conductor unit, and by arranging a first, second, and third reflective patch at intervals within the reflective radiation patches, with the second reflective patch positioned within a first hollow structure in the first reflective patch, the third reflective patch positioned within a second hollow structure in the second reflective patch, and a third hollow structure within the third reflective patch, the first, second, and third reflective patches can respectively form an outer ring oscillation circuit, a middle ring oscillation circuit, and an inner ring oscillation circuit. These oscillation circuits can achieve spatial coupling, thereby enabling the magnetic conductor array reflector to suppress back radiation and improve the actual gain of tri-band radiation. Furthermore, the magnetic conductor array reflector can reduce near-field coupling between electromagnetic waves and the human body, effectively reducing electromagnetic wave penetration into the body. By optimizing the radiation gain and safety of the tri-band antenna, the communication reliability, battery life, and wearing comfort of wearable devices are significantly improved.

[0029] Optional, Figure 2 This is a schematic diagram of the structure of a magnetic conductor array unit provided in an embodiment of this utility model. Figure 2 As shown, the first reflective patch 201 includes a first sub-reflective patch 2011, a second sub-reflective patch 2012, a third sub-reflective patch 2013, and a fourth sub-reflective patch 2014, which are respectively located at the four corners of the reflective medium substrate 22 and are spaced apart. The outer contours of the first sub-reflective patch 2011, the second sub-reflective patch 2012, the third sub-reflective patch 2013, and the fourth sub-reflective patch 2014 all include two right-angled sides arranged vertically and arc edges connected to the two right-angled sides respectively.

[0030] Specifically, the first reflective patch 201 may include a first sub-reflective patch 2011, a second sub-reflective patch 2012, a third sub-reflective patch 2013, and a fourth sub-reflective patch 2014 located at the upper left, upper right, lower left, and lower right corners of the reflective medium substrate 22, respectively. The first sub-reflective patch 2011, the second sub-reflective patch 2012, the third sub-reflective patch 2013, and the fourth sub-reflective patch 2014 are arranged in pairs at intervals, so that the electromagnetic distribution can be adjusted by the interval between the first sub-reflective patch 2011, the second sub-reflective patch 2012, the third sub-reflective patch 2013, and the fourth sub-reflective patch 2014. The outer contours of the first sub-reflective patch 2011, the second sub-reflective patch 2012, the third sub-reflective patch 2013, and the fourth sub-reflective patch 2014 all include two vertically arranged right-angled sides and arc edges connected to the two right-angled sides, thereby forming a first hollow structure 204 through the four arc edges of the first sub-reflective patch 2011, the second sub-reflective patch 2012, the third sub-reflective patch 2013, and the fourth sub-reflective patch 2014. An outer ring oscillation circuit is formed through the first reflective patch 201, thereby achieving zero-phase reflection at 5.8 GHz.

[0031] Optional, continue to refer to Figure 2 The second reflective patch 202 is circular in shape; the center point of the second reflective patch 202 coincides with the center point of the first hollow structure 204.

[0032] Specifically, the outer contour of the second reflective patch 202 is circular, the shape of the second hollow structure 205 is circular, and the center points of the second reflective patch 202 and the second hollow structure 205 coincide, so that the shape of the second reflective patch 202 is annular, which enables the formation of a middle-circuit oscillation circuit through the second reflective patch 203, and enables zero-phase reflection at 3.5GHz through the second reflective patch 203. At the same time, the center points of the second reflective patch 202 and the first hollow structure 204 coincide, ensuring the structural symmetry of the magnetic conductor array reflector 2.

[0033] Optional, continue to refer to Figure 2 The outer contour of the third reflective patch 203 is circular; the shape of the third hollow structure 206 is a superposition of the first sub-hollow structure 2061 and the second sub-hollow structure 2062, both of which are rounded rectangles; the center points of the first sub-hollow structure 2061 and the second sub-hollow structure 2062 coincide, and the first sub-hollow structure 2061 and the second sub-hollow structure 2062 are set perpendicular to each other.

[0034] Specifically, the outer contour of the third reflective patch 203 is circular, and the shape of the third hollow structure 206 is formed by stacking the first sub-hollow structure 2061 and the second sub-hollow structure 2062. The first and second sub-hollow structures 2061 and 2062 are both rounded rectangles, meaning their outer contours each include two parallel sides and two arcs on opposite sides. The center points of the first and second sub-hollow structures 2061 and 2062 coincide, and they are perpendicular to each other. Therefore, the shape of the third hollow structure 206 is composed of two perpendicularly arranged rounded rectangles, enabling the formation of an inner-ring oscillation circuit through the third reflective patch 203, thereby achieving 7GHz zero-phase reflection.

[0035] The first reflective patch 201, the second reflective patch 202, and the third reflective patch 203 ensure the structural symmetry of the magnetic conductor array reflector 2, so that the magnetic conductor array reflector 2 can maintain good performance when electromagnetic waves are incident at different incident angles. At the same time, the electromagnetic fields generated by the outer ring oscillation circuit, the middle ring oscillation circuit, and the inner ring oscillation circuit can mutually modulate the resonant frequencies through coupling effects, so as to achieve stable zero-phase reflection of the magnetic conductor array reflector 2 at the three frequency points, ensuring that the reflected electromagnetic waves are in phase with the incident electromagnetic waves, thereby significantly improving directivity and forward gain in the target frequency band.

[0036] Optional, Figure 3 This is a schematic diagram of an antenna radiating element structure provided by an embodiment of this utility model. Figure 3 As shown, the antenna radiating unit 1 also includes a main feed line 31 attached above the antenna dielectric substrate 11, and a first ground feed line 32 and a second ground feed line 33 located on opposite sides of the main feed line 31; one end of the main feed line 31 is connected to the bottom extension end of the first bow-shaped patch 121 and the bottom extension end of the second bow-shaped patch 122, respectively.

[0037] Specifically, the main feed line 31 is used to input the electrical signal output by the wireless communication module built into the wearable device to the antenna radiating element 1. One end of the main feed line 31 is connected to the bottom extension end of the first bow-shaped patch 121 and the bottom extension end of the first bow-shaped patch 121, so that the first bow-shaped patch 121, the first bow-shaped patch 121, and the first extension patch 123 can convert the electrical signal into electromagnetic waves and radiate them outward to the magnetic conductor array reflector 2, thereby enabling the antenna radiating element 1 to achieve tri-band radiation of 3.5GHz, 5.8GHz, and 7GHz. The first ground feed line 32 and the second ground feed line 33 are located on opposite sides of the main feed line 31. The first ground feed line 32 and the second ground feed line 33 are specifically used as grounding references, providing a current return path, balancing the electromagnetic field distribution in the antenna radiating element 1, and ensuring stable transmission of the electrical signal input to the antenna radiating element 1. The first grounding feed line 32 and the second grounding feed line 33 can have the same shape. The first grounding feed line 32 may include a first rectangular patch 321 and a second rectangular patch 322. The second rectangular patch 322 is located on the side of the first rectangular patch 321 that is close to the main feed line 31, and the longitudinal length of the second rectangular patch 322 is greater than the longitudinal length of the first rectangular patch 321, so as to enhance the coupling electric field strength and improve the energy transmission efficiency between the main feed line 31 and the antenna radiating patch 12.

[0038] Furthermore, by attaching the main feed line 31, the first ground feed line 32, and the second ground feed line 33 all above the antenna dielectric substrate 11, the transmission loss of electrical signals can be reduced through coplanar waveguide (CPW) feeding, ensuring that electrical signals can be efficiently transmitted to the first bow-shaped patch 121, the second bow-shaped patch 122, and the first extension patch 123 to support high radiation gain across the three frequency bands. Simultaneously, on the antenna dielectric substrate 11 made of flexible PDMS, the CPW structure can adapt to bending and stretching conditions to maintain impedance matching stability and reduce reflection loss caused by deformation.

[0039] Optional, continue to refer to Figure 3 The antenna radiating patch 12 also includes a second extension patch 124, which is connected between the main feed line 31 and the bottom extension end of the first bow-shaped patch 121 and the bottom extension end of the second bow-shaped patch 122.

[0040] Specifically, the second extension patch 124 is connected between the main feed line 31 and the bottom extension ends of the first bow-shaped patch 121 and the second bow-shaped patch 122. The second extension patch 124 serves as an intermediate link for current transmission, transmitting the electrical signal input from the main feed line 31 to the first bow-shaped patch 121, the second bow-shaped patch 122, and the first extension patch 123, thereby further extending the current path in the antenna radiating patch 12. The connection between the second extension patch 124 and the bottom extension ends of the first bow-shaped patch 121 and the second bow-shaped patch 122 increases the physical length and geometric complexity of current propagation, ensuring that the antenna radiating element 1 can achieve tri-frequency resonance at 3.5GHz, 5.8GHz, and 7GHz, and reducing the reflection coefficient of the antenna radiating element 1 at these three frequencies, thereby improving the radiation gain.

[0041] Optional, Figure 4 This is a schematic diagram of another antenna radiating element provided in an embodiment of this utility model. (See diagram below.) Figure 4 As shown, in order to ensure that the antenna radiating element 1 can achieve tri-band radiation of 3.5GHz, 5.8GHz and 7GHz, the electrical dimensional parameters of each structure in the antenna radiating element 1 can be specifically set as follows: the length L of the antenna dielectric substrate 11 along the longitudinal direction is between 0.266λ0 and 0.327λ0, the width W of the antenna dielectric substrate 11 along the transverse direction is between 0.175λ0 and 0.222λ0, the length Ls of the first extension patch 123 along the longitudinal direction is between 0.064λ0 and 0.076λ0, and the width W5 of the second extension patch 124 along the transverse direction is between 0.053λ0 and 0.084λ0. The first grounding feeder 32 and the second grounding feeder 33 have the same dimensions, and the longitudinal length Lg of the first rectangular patch 321 is between 0.058λ0 and 0.093λ0, and the transverse width Wg of the second rectangular patch 322 is between 0.006λ0 and 0.074λ0. The first bow-shaped patch 121 and the second bow-shaped patch 122 have the same dimensions, and the width W11 of the connection structure between the top extension end of the first bow-shaped patch 121 and the top extension end of the second bow-shaped patch 122 along the lateral direction is between 0.131λ0 and 0.173λ0, the length L10 of the first straight portion along the longitudinal direction is between 0.029λ0 and 0.053λ0, the width W9 of the second straight portion along the lateral direction is between 0.035λ0 and 0.056λ0, the length L7 of the fifth straight portion along the longitudinal direction is between 0.049λ0 and 0.078λ0, and the distance W6 between the second extended patch 124 and the fifth straight portion is between 0.047λ0 and 0.069λ0.

[0042] at the same time, Figure 5This is a schematic diagram of another magnetic conductor array reflector provided in an embodiment of this utility model. Figure 5 As shown, to ensure that the magnetic conductor array reflector 2 can achieve zero-phase reflection at 3.5GHz, 5.8GHz, and 7GHz, the electrical dimensional parameters of each structure in the magnetic conductor array reflector 2 can be specifically set as follows: the width Ws of the reflective medium substrate 22 along the lateral direction is between 0.287λ0 and 0.333λ0, and the width W1 of the first reflective patch 201 along the lateral direction is between 0.278λ0 and 0.298λ0. The first sub-reflective patch 2011, the second sub-reflective patch 2012, the third sub-reflective patch 2013, and the fourth sub-reflective patch 2014 have the same size, and the length W2 of the right-angled side of the first sub-reflective patch 2011 is between 0.114λ0 and 0.131λ0. The radius r1 of the second reflective patch 202 ranges from 0.11λ0 to 0.119λ0, the radius r2 of the second hollow structure 205 ranges from 0.091λ0 to 0.103λ0, and the radius r3 of the third reflective patch 203 ranges from 0.063λ0 to 0.072λ0. The first sub-hollow structure 2061 and the second sub-hollow structure 2062 have the same dimensions, and the length W3 of the parallel side of the first sub-hollow structure 2061 ranges from 0.023λ0 to 0.074λ0, and the distance W4 between the two parallel sides of the first sub-hollow structure 2061 ranges from 0.009λ0 to 0.015λ0. Here, λ0 is the free space wavelength, which can be approximately 3 × 10⁻⁶ based on the speed of light. 8 The ratio of m / s and radiation frequency is determined. For example, to achieve tri-band radiation of 3.5GHz, 5.8GHz, and 7GHz, λ0 can be determined based on the speed of light and 3.5GHz, i.e., the value of λ0 can be 85.7mm. This ensures that the antenna radiation element 1 can achieve tri-band radiation of 3.5GHz, 5.8GHz, and 7GHz, and that the magnetic conductor array reflector 2 can achieve zero-phase reflection of 3.5GHz, 5.8GHz, and 7GHz. This optimizes the radiation gain and security of the tri-band antenna, significantly improves the communication reliability, battery life, and wearing comfort of the wearable device, and enables the wearable device to adapt to various application scenarios.

[0043] To verify that after setting the antenna radiating element 1 with the above-mentioned electrical dimensional parameters and the magnetic conductor array reflector 2 with the above-mentioned electrical dimensional parameters in the tri-band antenna, the tri-band antenna can achieve tri-band radiation of 3.5GHz, 5.8GHz and 7GHz, and achieve zero phase reflection at 3.5GHz, 5.8GHz and 7GHz, the following simulation test can be performed on the tri-band antenna. Figure 6A schematic diagram of the reflection characteristic curve of the magnetic conductor array reflector provided in the embodiment of this utility model is shown below. Figure 6 As shown, Figure 6 (a) shows the reflection amplitude curve of the magnetic conductor array reflector 2. Figure 6 (b) shows the reflection phase characteristic curve of the magnetic conductor array reflector 2. The reflection phase characteristic curve shows that the magnetic conductor array reflector 2 can achieve zero-phase reflection at 3.5 GHz, 5.8 GHz and 7 GHz. The reflection amplitude curve shows that the reflection coefficient of the magnetic conductor array reflector 2 is -0.22 dB at 3.5 GHz, -0.28 dB at 5.8 GHz and -0.29 dB at 7 GHz.

[0044] Figure 7 This is a schematic diagram illustrating the influence of electromagnetic waves with different polarization angles on the reflection characteristics of a magnetic conductor array reflector, provided as an embodiment of the present invention. Figure 7 (a) is a graph showing the effect of electromagnetic waves with different polarization angles incident perpendicularly on the reflectivity characteristics of the magnetic conductor array reflector 2. Figure 7 (b) is a graph showing the effect of electromagnetic waves with different polarization angles incident perpendicularly on the reflection phase characteristics of the magnetic conductor array reflector 2. Figure 7 (a) and Figure 7 (b) It can be seen that when electromagnetic waves with different polarization angles are incident perpendicularly on the magnetic conductor array reflector 2, the reflectivity and reflection phase of the magnetic conductor array reflector 2 show only slight differences, indicating that it has good polarization insensitivity characteristics. Thus, the tri-band antenna can still maintain stable electromagnetic performance in complex application scenarios such as dynamic wearables and attitude changes, and has excellent environmental adaptability and robustness.

[0045] Figure 8 This is a schematic diagram illustrating the effect of rotation of the magnetic conductor array reflector structure on the reflection phase, provided in an embodiment of the present invention. Figure 8 (a) is a schematic diagram of the structure of the magnetic conductor array reflector 2 rotated. Figure 8 (b) is a graph showing the effect of different rotation angles on the reflection phase of the magnetic conductor array reflector 2. Figure 8 (b) It can be seen that, based on the structural symmetry of the magnetic conductor array reflector 2, its reflection phase curve remains basically stable when the magnetic conductor array reflector 2 rotates. At the same time, under the condition of perpendicular incidence of electromagnetic waves at different polarization angles, the reflectivity of the magnetic conductor array reflector 2 hardly changes significantly, indicating that it has good polarization stability and structural robustness.

[0046] Figure 9 A schematic diagram of the equivalent circuit of the magnetic conductor array reflector provided in the embodiment of this utility model is shown below. Figure 9As shown, the equivalent circuit of the magnetic conductor array reflector 2 consists of a free space impedance Z with an impedance of 377Ω, an equivalent impedance R1 of the reflective dielectric substrate 22 with an impedance of 377Ω, and two sets of LC resonant branches. The middle ring oscillation circuit consists of a first inductor L1 with an inductance of 1.31nH and a first capacitor C1 with a capacitance of 0.06pF, which can generate a resonance of about 3.5GHz. The outer ring oscillation circuit consists of a second inductor L2 with an inductance of 13.88nH and a second capacitor C2 with a capacitance of 0.049pF, which can generate a resonance of about 5.8GHz. The inner ring oscillation circuit consists of a third inductor L3 with an inductance of 9.67nH, a third capacitor C3 with a capacitance of 0.19pF, a fourth inductor L4 with an inductance of 7.89nH, and a fourth capacitor C4 with a capacitance of 0.06pF, which can generate a resonance of about 7GHz. Figure 10 This is a schematic diagram of the reflection phase curve of the equivalent circuit of the magnetic conductor array reflector provided in this embodiment of the invention. Figure 10 As can be seen, the red curve is the reflection phase curve of the equivalent circuit, and the blue curve is the reflection phase curve of the magnetic conductor array reflector 2 in the operating frequency band. The two have a high degree of agreement, which verifies the effectiveness of the established circuit model and can be used to realize the rapid modeling and optimization design of the magnetic conductor array reflector 2.

[0047] Figure 11 This is a structural schematic diagram showing the reflection coefficient curves of the antenna radiating element before and after loading the magnetic conductor array reflector, as provided in an embodiment of this utility model. Figure 11 It can be seen that without the magnetic conductor array reflector 2, the antenna radiating element 1 exhibits three distinct resonances at approximately 3.35 GHz, 5.73 GHz, and 6.92 GHz, corresponding to a three-band operating mode. After loading the magnetic conductor array reflector 2, the resonant frequencies stabilize at approximately 3.49 GHz, 5.82 GHz, and 7.04 GHz, respectively, and the reflection coefficients in each frequency band are significantly improved, indicating that the introduction of the magnetic conductor array reflector 2 effectively optimizes the impedance matching characteristics. Simultaneously, it can be observed that the measured results and simulation curves maintain good consistency in overall trend, with only slight frequency shifts and bandwidth differences. This is mainly due to errors in the dielectric constant of the flexible substrate, the surface impedance of the conductive cloth, and minor deformations during welding and bending. The loading of the magnetic conductor array reflector 2 makes the impedance matching of the antenna more stable in the three operating frequency bands, verifying the effectiveness of the collaborative design of the antenna radiating element 1 and the magnetic conductor array reflector 2 in improving multi-band performance.

[0048] Figure 12 This is a schematic diagram of the reflection coefficient curves of a three-frequency antenna based on an artificial magnetic conductor structure provided in an embodiment of the present invention under different bending directions and bending radii. Figure 12 (a) shows the simulation results when bending along the x-axis. Figure 12(b) Simulation results for bending along the y-axis. The solid red line represents the tri-band antenna in a planar state, while the orange dotted line, green dashed line, and blue dashed line correspond to bending radii of 50mm, 75mm, and 100mm, respectively. Figure 12 As can be seen, regardless of whether it is bent along the x-axis or y-axis, the tri-band antenna maintains stable multi-frequency resonance characteristics in the three operating frequency bands of 3.5GHz, 5.8GHz, and 7.0GHz. With the decrease of the bending radius, only slight frequency shifts occur at the resonant points of each frequency band; the reflection coefficient curves in the mid-to-high frequency bands change slightly, while the low frequency band remains almost unaffected. Overall, the tri-band antenna maintains good impedance matching characteristics and stable multi-band operating performance under different directions and radii of curvature, indicating that this flexible tri-band antenna possesses excellent mechanical reliability and electromagnetic stability.

[0049] Figure 13 The far-field radiation pattern of the three-band antenna based on an artificial magnetic conductor structure provided in this embodiment of the invention, wherein, Figure 13 (a) shows the far-field radiation patterns of the tri-band antenna in the E-plane and H-plane at 3.5 GHz. Figure 13 (b) shows the far-field radiation patterns of the tri-band antenna in the E and H planes at 5.8 GHz. Figure 13 (c) shows the far-field radiation patterns of the tri-band antenna in the E and H planes at 7 GHz, derived from... Figure 13 (a) Figure 13 (b) and Figure 13 (c) It can be seen that without the magnetic conductor array reflector 2, the tri-band antenna exhibits approximately omnidirectional radiation characteristics on the E-plane and a typical bidirectional radiation distribution on the H-plane, with strong back radiation. After loading the magnetic conductor array reflector 2, the main lobe directions on the E-plane and H-plane are significantly concentrated, back radiation is significantly suppressed, the front-to-back lobe ratio is significantly improved, and the radiated energy is mainly directed towards the spatial region away from the human body. Within the three operating frequency bands, the tri-band antenna with the magnetic conductor array reflector 2 exhibits stable unidirectional radiation characteristics, with consistent main lobe directions, indicating that the magnetic conductor array reflector 2 provides in-phase reflection, effectively enhancing forward radiation and reducing power leakage in the direction of the human body. This result verifies the rationality of the collaborative design of antenna radiating element 1 and magnetic conductor array reflector 2 and its effectiveness in improving directivity and radiation efficiency in multiple frequency bands.

[0050] Figure 14 A simulated three-dimensional far-field radiation diagram of a three-band antenna based on an artificial magnetic conductor structure, provided for an embodiment of this utility model. Figure 14 (a) shows the radiation effect of the tri-band antenna at 3.5 GHz. Figure 14 (b) shows the radiation effect of the tri-band antenna at 5.8 GHz. Figure 14 (c) shows the radiation effect of the tri-band antenna at 7 GHz. Figure 14 As can be seen, the tri-band antenna exhibits obvious unidirectional radiation characteristics in all three operating frequency bands, with a stable main lobe direction and a significantly increased front-to-back lobe difference. After loading the magnetic conductor array reflector 2, the measured maximum gain of the tri-band antenna increased from 1.72 dBi to 6.39 dBi at 3.5 GHz, from 1.82 dBi to 6.24 dBi at 5.8 GHz, and from 3.82 dBi to 8.14 dBi at 7 GHz. The results show that the magnetic conductor array reflector 2 can significantly enhance forward gain, improve directivity, and effectively suppress back radiation across multiple frequency bands.

[0051] Figure 15 The simulation results of the specific absorption rate of the tri-band antenna based on the artificial magnetic conductor structure provided for the embodiment of this utility model under conditions close to the human body model are shown in the figure. Figure 15 (a) and Figure 15 (b) are simulation results of the specific absorption rate of the tri-band antenna at 3.5 GHz. Figure 15 (c) and Figure 15 (d) are simulation results of the specific absorption rate of the tri-band antenna at 5.8 GHz. Figure 15 (e) and Figure 15 (f) are simulation results of the specific absorption rate of the tri-band antenna at 7 GHz. Figure 15 (a) Figure 15 (c) and Figure 15 (e) are all results of specific absorption rate simulation of 10g human tissue. Figure 15 (b) Figure 15 (d) and Figure 15(f) are the simulation results of specific absorption rate (SAR) for 1g of human tissue. The simulation results show that at 3.5GHz, the maximum SAR values ​​are 0.151W / kg (10g) and 0.27W / kg (1g); at 5.8GHz, the maximum SAR values ​​are 0.23W / kg (10g) and 0.427W / kg (1g); and at 7GHz, the maximum SAR values ​​are 0.29W / kg (10g) and 0.549W / kg (1g). All of these results are far below the safety standard for specific absorption rate of human tissue (1.6W / kg for 1g of tissue, 2W / kg for 10g of tissue). Therefore, the magnetic conductor array reflector 2 can effectively suppress the electromagnetic radiation of the tri-band antenna to the human body, significantly reduce the SAR level, and ensure the electromagnetic safety of wearable devices in multi-band near-human use scenarios. Furthermore, at 3.5 GHz, the maximum SAR values ​​for 1g tissue from the chest, arm, and leg using the tri-band antenna were 0.27 W / kg, 0.08 W / kg, and 0.069 W / kg, respectively; and the maximum SAR values ​​for 10g tissue from the chest, arm, and leg were 0.151 W / kg, 0.045 W / kg, and 0.036 W / kg, respectively. At 5.8 GHz, the maximum SAR values ​​for 1g tissue from the chest, arm, and leg using the tri-band antenna were 0.427 W / kg, 0.575 W / kg, and 0.069 W / kg, respectively. The maximum SAR values ​​for 10g of tissue in the chest, arms, and legs were 0.23W / kg, 0.336W / kg, and 0.111W / kg, respectively. At 7GHz, the maximum SAR values ​​for 1g of tissue in the chest, arms, and legs were 0.549W / kg, 0.666W / kg, and 0.239W / kg, respectively, while the maximum SAR values ​​for 10g of tissue in the chest, arms, and legs were 0.29W / kg, 0.345W / kg, and 0.131W / kg, respectively. The relatively high SAR value in the chest area and the significantly lower SAR values ​​in the arms and legs indicate that the tri-band antenna provides excellent electromagnetic safety and radiation suppression in practical wear scenarios.

[0052] Figure 16 The measured far-field radiation pattern of the tri-band antenna based on the artificial magnetic conductor structure provided in this embodiment of the invention when bent along the x-axis under different bending radii. Figure 16 (a) Figure 16 (b) and Figure 16(c) Corresponding to operating frequencies of 3.5 GHz, 5.8 GHz, and 7.0 GHz, respectively. It can be seen that, under conditions of no bending and different bending radii, the main lobe of the tri-band antenna maintains its lateral pointing characteristics in all three frequency bands, and back radiation is effectively suppressed. When the bending radius is reduced to 50 mm, the overall shape of the radiation pattern in each frequency band remains basically unchanged, with only slight lobe broadening and sidelobe undulations appearing in the mid-frequency band. The results show that the tri-band antenna possesses good directivity retention and mechanical robustness when bent along the x-axis, verifying the stable radiation performance of the tri-band antenna under bending conditions.

[0053] Figure 17 The measured far-field radiation pattern of the tri-band antenna based on the artificial magnetic conductor structure provided in this embodiment of the invention when bent along the y-axis under different bending radii. Figure 17 (a) Figure 17 (b) and Figure 17 (c) Corresponding to the operating frequencies of 3.5 GHz, 5.8 GHz, and 7.0 GHz, respectively. As the bending radius decreases, the main lobe direction of the antenna remains stable across all frequency bands, with no significant shift in the lateral radiation pattern. Only a slight lobe splitting phenomenon is observed in the 7.0 GHz high-frequency band. In contrast, the low-frequency 3.5 GHz mode is least affected by curvature and exhibits the highest radiation stability. Overall, the results show that the tri-band antenna can maintain stable radiation pattern characteristics and a high front-to-back lobe ratio even under y-axis bending conditions, further verifying its excellent flexibility and electromagnetic stability.

[0054] Based on the same inventive concept, this utility model embodiment also provides a wearable device, which includes the tri-band antenna based on the artificial magnetic conductor structure described in the above embodiment.

[0055] Therefore, the wearable device provided in this embodiment has the structure and operation of the tri-band antenna based on the artificial magnetic conductor structure in the above embodiment, and can achieve the effect of the tri-band antenna based on the artificial magnetic conductor structure in the above embodiment. The similarities can be referred to the above description, and will not be repeated here.

[0056] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A tri-band antenna based on an artificial magnetic conductor structure, characterized in that, include: Antenna radiating element, magnetic conductor array reflector, and air layer; The antenna radiating element includes an antenna dielectric substrate and an antenna radiating patch attached to the antenna dielectric substrate; the antenna radiating patch includes at least a first bow-shaped patch, a second bow-shaped patch, and a first extension patch; The first bow-shaped patch and the second bow-shaped patch are arranged opposite to each other along a first direction and are connected to each other; the first extension patch is located between the first bow-shaped patch and the second bow-shaped patch, and is connected to both the first bow-shaped patch and the second bow-shaped patch; The magnetic conductor array reflector comprises n×m periodically arranged magnetic conductor units; n is a positive integer greater than or equal to 2, and m is a positive integer greater than or equal to 2. The magnetic conductor unit includes a reflective dielectric substrate, a reflective radiation patch attached to one side of the reflective dielectric substrate, and a radiation backplate attached to the side of the reflective dielectric substrate opposite to the reflective radiation patch; the reflective radiation patch includes a first reflective patch, a second reflective patch, and a third reflective patch spaced apart; the first reflective patch includes a first cutout structure; the second reflective patch is located within the first cutout structure and includes a second cutout structure; the third reflective patch is located within the second cutout structure and includes a third cutout structure. The air layer is located between the antenna radiating element and the magnetic conductor array reflector, and the antenna dielectric substrate is located on the side of the air layer away from the reflective radiating patch.

2. The tri-band antenna based on an artificial magnetic conductor structure according to claim 1, characterized in that, The first reflective patch includes a first sub-reflective patch, a second sub-reflective patch, a third sub-reflective patch, and a fourth sub-reflective patch, which are respectively located at the four corners of the reflective medium substrate and are spaced apart. The outer contours of the first sub-reflective patch, the second sub-reflective patch, the third sub-reflective patch, and the fourth sub-reflective patch all include two right-angled sides arranged perpendicularly to each other and rounded edges connected to the two right-angled sides respectively.

3. The tri-band antenna based on an artificial magnetic conductor structure according to claim 1, characterized in that, The second reflective patch is circular in shape; The center point of the second reflective patch coincides with that of the first hollow structure.

4. The tri-band antenna based on an artificial magnetic conductor structure according to claim 1, characterized in that, The outer contour of the third reflective patch is circular; the shape of the third hollow structure is a combination of a first sub-hollow structure and a second sub-hollow structure, both of which are rounded rectangles. The center points of the first sub-hollow structure and the second sub-hollow structure coincide, and the first sub-hollow structure and the second sub-hollow structure are set perpendicular to each other.

5. The tri-band antenna based on an artificial magnetic conductor structure according to claim 1, characterized in that, The antenna radiating element also includes a main feed line attached to the antenna dielectric substrate, and a first ground feed line and a second ground feed line located on opposite sides of the main feed line. One end of the main feeder is connected to the bottom extension end of the first bow-shaped patch and the bottom extension end of the second bow-shaped patch, respectively.

6. The tri-band antenna based on an artificial magnetic conductor structure according to claim 5, characterized in that, The antenna radiating patch also includes a second extension patch; The second extension patch is connected between the main feed line and the bottom extension end of the first bow-shaped patch and the bottom extension end of the second bow-shaped patch.

7. The tri-band antenna based on an artificial magnetic conductor structure according to claim 1, characterized in that, The longitudinal length L of the antenna dielectric substrate is in the range of 0.266λ0 < L < 0.327λ0; The width W of the antenna dielectric substrate in the lateral direction ranges as follows: 0.175λ0 < W < 0.222λ0; The length L1 of the first extension patch along the longitudinal direction ranges from 0.064λ0 to L1 to 0.076λ0. The value range of the transverse width Ws of the reflective medium substrate is: 0.287λ0 < Ws < 0.333λ0; The width W1 of the first reflective patch in the lateral direction ranges as follows: 0.278λ0 < W1 < 0.298λ0; λ0 is the wavelength in free space.

8. The tri-band antenna based on an artificial magnetic conductor structure according to claim 3, characterized in that, The radius r1 of the second reflective patch has the following range: 0.11λ0 < r1 < 0.119λ0; The radius r2 of the second hollow structure has a range of values: 0.091λ0 < r2 < 0.103λ0; λ0 is the wavelength in free space.

9. The tri-band antenna based on an artificial magnetic conductor structure according to claim 6, characterized in that, The value range of the width W5 of the second extension patch along the horizontal direction is: 0.053λ0 < W5 < 0.084λ0; λ0 is the wavelength in free space.

10. A wearable device, characterized in that, include: The tri-band antenna based on an artificial magnetic conductor structure as described in any one of claims 1-9.

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