Dual-band antenna and wearable device

Abstract

The utility model discloses a dual -frequency antenna and wearable equipment relates to antenna technical field. Dual -frequency antenna includes: antenna radiation unit, magnetic conductor array reflection board and air layer, antenna radiation unit includes antenna dielectric substrate and the antenna radiation patch of being pasted on its top, the antenna radiation patch includes T type patch, the magnetic conductor array reflection board includes n x m periodic arrangement's magnetic conductor unit, the magnetic conductor unit includes reflection dielectric substrate, reflection radiation patch and radiation backplate respectively pasted on the top and the bottom of reflection dielectric substrate, reflection radiation patch includes interval setting's first reflection patch and second reflection patch, second reflection patch is located in the first hollow structure in first reflection patch, second reflection patch includes second hollow structure, air layer is located between antenna radiation unit and magnetic conductor array reflection board, and antenna dielectric substrate is located air layer far from reflection radiation patch one side, the utility model has improved the radiation gain of dual -frequency antenna in dual -frequency band.

Description

Technical Field

[0001] This utility model relates to the field of antenna technology, and in particular to a dual-band antenna and a wearable device. Background Technology

[0002] With the development of the Internet of Things, wireless body area networks, smart medical devices, and personal communication devices, wearable antennas are widely used in vital sign monitoring and short-range wireless data transmission due to their thinness, flexibility, and ease of integration. Among them, 3.5GHz has a wide coverage and low propagation loss, providing a stable link for wireless body area communication and medical monitoring, while 5.8GHz is compatible with short-range high-speed protocols such as WLAN and Wi-Fi, making it suitable for large-scale data sensing and real-time interaction. Therefore, 3.5GHz and 5.8GHz have become common frequency band choices for dual-band wearable antennas.

[0003] Wearable antennas in the present technology usually adopt a design that combines an antenna radiating element with an artificial magnetic conductor array reflector. The artificial magnetic conductor array reflector achieves zero-phase reflection at the target frequency, effectively suppressing the back radiation of the antenna radiating element and reducing the near-field coupling between the antenna radiating element and the human body, thereby reducing the specific absorption rate (SAR) and improving the radiation gain.

[0004] However, most wearable antennas in the current technology are optimized for single frequency. When dual frequencies coexist, the ability to suppress back radiation and reduce SAR is unbalanced, resulting in large performance fluctuations of wearable antennas in dual frequency bands, which limits the stability and communication reliability of wearable antennas in dual frequency band applications. Utility Model Content

[0005] This invention provides a dual-band antenna and a wearable device. By setting an antenna radiating patch and a reflective radiating patch as a preset structure, the back radiation of the dual-band antenna in both frequency bands is suppressed, and its radiation gain in both frequency bands is improved.

[0006] The first aspect of this utility model provides a dual-frequency antenna, which includes: an antenna radiating element, a magnetic conductor array reflector, and an air layer;

[0007] The antenna radiating element includes an antenna dielectric substrate and an antenna radiating patch attached above the antenna dielectric substrate; the antenna radiating patch includes at least a T-shaped patch;

[0008] 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.

[0009] The magnetic conductor unit includes a reflective dielectric substrate, a reflective radiation patch attached above the reflective dielectric substrate, and a radiation backplate attached below the reflective dielectric substrate; the reflective radiation patch includes a first reflective patch and a second reflective patch spaced apart; the first reflective patch includes a first hollow structure; the second reflective patch is located within the first hollow structure; the second reflective patch includes at least one second hollow structure;

[0010] 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.

[0011] Optionally, the second reflective patch includes two second hollow structures that are symmetrically arranged and not connected to each other.

[0012] Optionally, the centers of the first reflective patch and the second reflective patch coincide.

[0013] 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;

[0014] One end of the main feeder is connected to the T-shaped patch.

[0015] Optionally, the antenna radiating patch further includes a first extension patch;

[0016] The first extension patch is connected between the main feed line and the T-shaped patch.

[0017] Optionally, the first extension patch includes a first sub-extension patch and a first M-type patch and a second M-type patch located on opposite sides of the first sub-extension patch;

[0018] The first side of the first sub-extension patch is connected to one end of the T-shaped patch that extends in the longitudinal direction, and the first sub-extension patch is provided with a first opening structure.

[0019] The second side and the third side of the first sub-extension patch are respectively connected to the first M-type patch and the second M-type patch, and the second side and the third side are both arranged adjacent to the first side;

[0020] The main feeder is connected to the first M-type patch and the second M-type patch, respectively.

[0021] Optionally, the longitudinal length L of the antenna dielectric substrate is in the range of 0.222λ0 < L < 0.7λ0;

[0022] The width W of the antenna dielectric substrate in the lateral direction ranges as follows: 0.187λ0 < W < 0.327λ0;

[0023] The value range of the longitudinal length L1 of the T-shaped patch is: 0.033λ0 < L1 < 0.064λ0;

[0024] The value range of the width W9 of the T-shaped patch along the horizontal direction is: 0.163λ0 < W9 < 0.198λ0;

[0025] The width Ws of the reflective medium substrate in the transverse direction ranges as follows: 0.18λ0 < Ws < 0.196λ0;

[0026] The width W1 of the first reflective patch in the lateral direction ranges as follows: 0.153λ0 < W1 < 0.162λ0;

[0027] The width W2 of the second reflective patch in the lateral direction ranges as follows: 0.126λ0 < W2 < 0.14λ0;

[0028] λ0 is the wavelength in free space.

[0029] Optionally, the distance W3 between the two second hollow structures can be in the range of: 0.006λ0 < W3 < 0.07λ0;

[0030] λ0 is the wavelength in free space.

[0031] Optionally, the width W4 of the first sub-extension patch in the lateral direction ranges from 0.047λ0 to W4 to 0.089λ0.

[0032] The width W7 of the first opening structure in the transverse direction ranges from 0.001λ0 to W7 to 0.062λ0.

[0033] λ0 is the wavelength in free space.

[0034] The second aspect of this utility model provides a wearable device, which includes the dual-band antenna described above.

[0035] The technical solution of this utility model involves setting an antenna radiating element, a magnetic conductor array reflector, and an air layer in a dual-band antenna. 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. This allows the antenna radiating element to convert electrical signals into electromagnetic waves for outward radiation. The magnetic conductor array reflector achieves zero-phase reflection at the target frequency, and the air layer enhances the resonant stability of the dual-band antenna by providing appropriate spacing. By setting an antenna dielectric substrate and an antenna radiating patch attached above the antenna dielectric substrate in the antenna radiating element, and by setting a T-shaped patch in the antenna radiating patch, the current path in the antenna radiating patch can be extended, introducing additional resonant modes, thereby enabling the antenna radiating patch to achieve dual-band radiation. By setting n×m periodically arranged magnetic conductor elements in the magnetic conductor array reflector, the magnetic conductor array reflector can achieve zero-phase reflection through the coordinated operation of multiple magnetic conductor elements. By incorporating a reflective dielectric substrate within a magnetic conductor unit, and attaching reflective radiation patches and a radiation backplate above and below the substrate respectively, and by spaced first and second reflective patches within the reflective radiation patches, placing the second reflective patch within a first perforated structure in the first reflective patch, and by providing at least one second perforated structure within the second reflective patch, the first and second reflective patches can respectively form an outer-ring oscillation circuit and an inner-ring oscillation circuit, achieving spatial coupling between the two. This allows the magnetic conductor array reflector to suppress back radiation and improve the actual gain of dual-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 dual-band antenna, the communication reliability, battery life, and wearing comfort of wearable devices are significantly improved.

[0036] 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

[0037] 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.

[0038] Figure 1 This is a schematic diagram of the structure of a dual-frequency antenna provided in an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of the structure of a magnetic conductor array unit provided in an embodiment of the present invention;

[0040] Figure 3 This is a schematic diagram of the structure of an antenna radiating unit provided in an embodiment of this utility model;

[0041] Figure 4 This is a schematic diagram of another antenna radiating element provided in this embodiment of the present invention;

[0042] Figure 5 This is a schematic diagram of another magnetic conductor array reflector provided in this embodiment of the present invention;

[0043] Figure 6 A schematic diagram of the reflection characteristic curve of the magnetic conductor array reflector provided in this embodiment of the utility model;

[0044] Figure 7 A schematic diagram of the equivalent circuit of the magnetic conductor array reflector provided in this embodiment of the utility model;

[0045] Figure 8 A schematic diagram of the reflection characteristic curve of the equivalent circuit of the magnetic conductor array reflector provided in the embodiment of this utility model;

[0046] Figure 9 A schematic diagram of the effect curve of the rotation of the magnetic conductor array reflector structure on its reflection coefficient provided in an embodiment of this utility model;

[0047] Figure 10 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;

[0048] Figure 11 Normalized far-field radiation pattern of a dual-frequency antenna provided in this embodiment of the present invention;

[0049] Figure 12 A simulation result of the specific absorption rate of the dual-band antenna at 3.5 GHz provided for an embodiment of this utility model;

[0050] Figure 13 The simulation results of the specific absorption rate of the dual-frequency antenna at 5.8 GHz provided in this embodiment of the utility model are shown in the figure. Detailed Implementation

[0051] 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.

[0052] 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.

[0053] Figure 1 This is a schematic diagram of the structure of a dual-frequency antenna provided in an embodiment of this utility model. Figure 1 As shown, the dual-band antenna 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 above the antenna dielectric substrate 11; the antenna radiating patch 12 includes at least a T-shaped patch 101; 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 element 21 includes a reflective dielectric substrate 22 and a reflective element attached above the reflective dielectric substrate 22. The antenna radiating patch 23 and the radiating backplate attached below the reflective dielectric substrate 22; the reflective radiating patch 23 includes a first reflective patch 201 and a second reflective patch 202 spaced apart; the first reflective patch 201 includes a first cutout structure 203; the second reflective patch 202 is located within the first cutout structure 203; the second reflective patch 202 includes at least one second cutout structure 204; an air layer is located 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.

[0054] Specifically, the antenna radiating element 1 is used to receive frequency signals output by the wireless communication module built into wearable devices, such as smartwatches or medical testing equipment, for example, dual-frequency signals of 3.5GHz and 5.8GHz. 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 and 5.8GHz, 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 resonant stability of the dual-band antenna in both 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 dual-band antenna.

[0055] Specifically, the antenna radiating unit 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 3.1 and possesses flexibility, transparency, good mechanical stability, and excellent biocompatibility, meeting the requirements of wearable applications. The thickness of the antenna dielectric substrate 11 can be 1 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 thickness of the antenna radiating patch 12 can be 0.08 mm. The antenna radiating patch 12 includes at least a T-shaped patch 101, which includes two ends extending laterally and one end extending longitudinally. By providing the T-shaped patch 101 in the antenna radiating patch 12, the current path in the antenna radiating patch 12 can be extended, introducing additional resonant modes. Meanwhile, the T-shaped patch 101 not only achieves the stability of dual-band radiation of the antenna radiating element 1, but also ensures that the antenna radiating element 1 maintains better current distribution and radiation characteristics when bent.

[0056] 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 and 5.8GHz, 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 3×3 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 the 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 waves radiated by the antenna radiation unit 1 are 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, and the thickness of the reflective radiation patch 23 can be 0.08 mm.

[0057] The reflective radiation patch 23 includes a first reflective patch 201 and a second reflective patch 202 spaced apart. The first reflective patch 201 includes a first hollow structure 203 to form an outer ring oscillation circuit. The first hollow structure 203 increases distributed capacitance and inductance, generating low-frequency resonance, thereby enabling zero-phase reflection at 3.5 GHz. The second reflective patch 202 is located within the first hollow structure 203 and includes at least one second hollow structure 204 to form an inner ring oscillation circuit. For example, the second hollow structure 204 may include an arcuate profile to form a semi-circular or elliptical resonant path, increasing high-frequency electric field concentration, thereby enabling zero-phase reflection at 5.8 GHz. Simultaneously, the electromagnetic fields generated by the outer ring oscillation circuit and the inner ring oscillation circuit can be spatially coupled through the first hollow structure 203 to modulate each other's resonant frequencies, thereby achieving stable zero-phase reflection of the magnetic conductor array reflector 2 at both frequency points and ensuring that the reflected electromagnetic wave is in phase with the incident electromagnetic wave. Furthermore, the flexible properties of the PDMS reflective substrate 22 further enhance the stability of the magnetic conductor array reflector 2 under bending conditions.

[0058] Compared to traditional wearable antennas that can only be optimized for a single frequency, this dual-band antenna, by setting the antenna radiating patch 12 in the dual-band antenna to a preset structure, can achieve dual-band resonance at 3.5GHz and 5.8GHz. This significantly reduces the reflection coefficient of the dual-band antenna in both frequency bands, reduces energy loss, and improves the radiation gain of the dual-band antenna in both bands. Simultaneously, by setting the reflective radiating patch 23 in the dual-band antenna to a preset structure, zero-phase reflection can be achieved at target frequencies, such as 3.5GHz and 5.8GHz. 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 gain of the dual-band radiation. 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 dual-band antenna, the structural compactness of the dual-band antenna is improved, the radiation gain and security of the dual-band antenna 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.

[0059] In this embodiment, by incorporating an antenna radiating element, a magnetic conductor array reflector, and an air layer in a dual-band antenna, and 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 can convert electrical signals into electromagnetic waves for outward radiation. The magnetic conductor array reflector can achieve zero-phase reflection at the target frequency, and the air layer can enhance the resonant stability of the dual-band antenna by providing appropriate spacing. By incorporating an antenna dielectric substrate and an antenna radiating patch attached above the antenna dielectric substrate in the antenna radiating element, and by incorporating a T-shaped patch in the antenna radiating patch, the current path in the antenna radiating patch can be extended, introducing additional resonant modes, thereby enabling the antenna radiating patch to achieve dual-band radiation. By incorporating n×m periodically arranged magnetic conductor elements in the magnetic conductor array reflector, the magnetic conductor array reflector can achieve zero-phase reflection through the cooperative operation of multiple magnetic conductor elements. By incorporating a reflective dielectric substrate within a magnetic conductor unit, and attaching reflective radiation patches and a radiation backplate above and below the substrate respectively, and by spaced first and second reflective patches within the reflective radiation patches, placing the second reflective patch within a first perforated structure in the first reflective patch, and by providing at least one second perforated structure within the second reflective patch, the first and second reflective patches can respectively form an outer-ring oscillation circuit and an inner-ring oscillation circuit, achieving spatial coupling between the two. This allows the magnetic conductor array reflector to suppress back radiation and improve the actual gain of dual-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 dual-band antenna, the communication reliability, battery life, and wearing comfort of wearable devices are significantly improved.

[0060] 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 second reflective patch 202 includes two second hollow structures 204 that are symmetrically arranged and not connected to each other.

[0061] Specifically, the second reflective patch 202 includes two symmetrically arranged and unconnected second hollow structures 204. Each of the two second hollow structures 204 can include a first semi-circular hollow structure A1 and a second semi-circular hollow structure A2. The right-angled sides of the first semi-circular hollow structure A1 and the second semi-circular hollow structure A2 are symmetrically arranged along the center point of the second reflective patch 202 and are unconnected, thus ensuring the structural symmetry of the magnetic conductor array reflector 2. This allows the magnetic conductor array reflector 2 to maintain good performance when electromagnetic waves are incident at different angles. Simultaneously, the second reflective patch 202, including the two symmetrically arranged and unconnected second hollow structures 204, can expand the bandwidth and stabilize the zero-phase reflection point, enabling the second reflective patch 202 to achieve zero-phase reflection at 5.8 GHz.

[0062] Optional, continue to refer to Figure 2 The centers of the first reflective patch 201 and the second reflective patch 202 coincide.

[0063] Specifically, the second reflective patch 202 is located within the first hollow structure 203 inside the first reflective patch. The first reflective patch 201, the second reflective patch 202, and the first hollow structure 203 can all be rectangular patches, and the centers of the first reflective patch 201 and the second reflective patch 202 coincide. That is, the first reflective patch 201 can have a rectangular ring structure, allowing adjustment of the equivalent capacitance and resonant frequency of the magnetic conductor array reflector 2. The rectangular ring structure of the first reflective patch 201 can form an outer ring oscillation circuit, increasing distributed capacitance and inductance, and generating low-frequency resonance, thereby achieving zero-phase reflection at 3.5 GHz. The second reflective patch 202 is located within the first hollow structure 203, allowing the second reflective patch 202 to form an inner ring oscillation circuit. Two symmetrically arranged and unconnected second hollow structures 204 within the second reflective patch 202 can form a resonant path resembling a semicircle or ellipse to increase the concentration of the high-frequency electric field, thereby achieving zero-phase reflection at 5.8 GHz through the second reflective patch 202. Simultaneously, the electromagnetic fields generated by the outer and inner ring oscillation circuits can be spatially coupled through the first hollow structure 203, modulating each other's resonant frequencies to achieve stable zero-phase reflection of the magnetic conductor array reflector 2 at both frequency points. This ensures that the reflected electromagnetic wave is in phase with the incident electromagnetic wave, improving the actual gain of the dual-band radiation. Furthermore, the symmetrical structure of the first and second reflective patches 201 and 202 makes the magnetic conductor array reflector 2 insensitive to electromagnetic waves with different polarization angles incident perpendicularly, and it maintains good performance regardless of the incident angle of the electromagnetic wave.

[0064] Optional, Figure 3This is a schematic diagram of the structure of an antenna radiating element provided in 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 T-shaped patch 101.

[0065] 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 T-shaped patch 101, so that the T-shaped patch 101 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 dual-band radiation of 3.5GHz and 5.8GHz. 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. 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 T-shaped patch 101 to support high radiation gain in both 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.

[0066] Optional, continue to refer to Figure 3 The antenna radiating patch 12 also includes a first extension patch 102, which is connected between the main feed line 31 and the T-shaped patch 101.

[0067] Specifically, the first extension patch 102 is connected between the main feed line 31 and the T-shaped patch 101. The first extension patch 102 serves as an intermediate link for current transmission, transmitting the electrical signal input from the main feed line 31 to the T-shaped patch 101, thereby further extending the current path in the antenna radiating patch 12. The connection between the first extension patch 102 and the T-shaped patch 101 increases the physical length and geometric complexity of current propagation, ensuring that the antenna radiating element 1 can achieve dual-frequency resonance at 3.5GHz and 5.8GHz, and reducing the reflection coefficient of the antenna radiating element 1 at both frequencies, thereby improving the radiation gain.

[0068] Optional, continue to refer to Figure 3The first extension patch 102 includes a first sub-extension patch 103 and a first M-shaped patch 104 and a second M-shaped patch 105 located on opposite sides of the first sub-extension patch 103; the first side of the first sub-extension patch 103 is connected to one end of the T-shaped patch 101 extending in the longitudinal direction, and a first opening structure 106 is provided in the first sub-extension patch 103; the second side and the third side of the first sub-extension patch 103 are respectively connected to the first M-shaped patch 104 and the second M-shaped patch 105, and the second side and the third side are both adjacent to the first side; the main feeder 31 is connected to the first M-shaped patch 104 and the second M-shaped patch 105 respectively.

[0069] Specifically, the first side of the first sub-extension patch 103 is connected to one end of the T-shaped patch 101 extending in the longitudinal direction. The first sub-extension patch 103 has a first opening structure 106. The first sub-extension patch 103 serves as an extension of the current path of the antenna radiating element 1, enabling the guidance and distribution of current, thereby optimizing the dual-frequency resonance of the antenna radiating element 1 at 3.5 GHz and 5.8 GHz. Simultaneously, the first opening structure 106 further increases the inductance and capacitance effects, assisting in adjusting the resonant frequency of the antenna radiating element 1.

[0070] The second and third sides of the first sub-extension patch 103 are respectively connected to the first M-type patch 104 and the second M-type patch 105, and both the second and third sides are adjacent to the first side. Simultaneously, the main feed line 31 is connected to the first M-type patch 104 and the second M-type patch 105, respectively, to further guide and distribute current through the first M-type patch 104 and the second M-type patch 105. For example, the first M-type patch 104 may specifically include a first intermediate straight section 1041, a first upper oblique section 1042, a first upper straight section 1043, a first lower oblique section 1044, and a first lower straight section 1045; the second M-type patch 105 may specifically include a second intermediate straight section 1051, a second upper oblique section 1052, a second upper straight section 1053, a second lower oblique section 1054, and a second lower straight section 1055. The first end of the first upper oblique section 1042 and the first end of the first lower oblique section 1044 are respectively connected to the opposite ends of the first intermediate straight section 1041 extending longitudinally. The second end of the first upper oblique section 1042 is connected to the first upper straight section 1043, and the second end of the first lower oblique section 1044 is connected to the first lower straight section 1045. The first end of the second upper oblique section 1052 and the first end of the second lower oblique section 1054 are respectively connected to the opposite ends of the second intermediate straight section 1051 extending longitudinally. The second end of the second upper oblique section 1052 is connected to the second upper straight section 1053, and the second end of the second lower oblique section 1054 is connected to the second lower straight section 1055. The first intermediate straight section 1041 and the second intermediate straight section 1051 are respectively attached to the second side and the third side of the first sub-extension patch 103, the first lower straight section 1045 and the second lower straight section 1055 are connected, and the main feed line 31 is respectively connected to the first lower straight section 1045 and the second lower straight section 1055.

[0071] The first sub-extension patch 103, the first M-type patch 104, and the second M-type patch 105, by extending the current path and combining with the modulation effect of the first opening structure 106, finely tune the dual-frequency resonant point of the antenna radiating element 1, thereby further reducing the reflection coefficient of the antenna radiating element 1 at 3.5 GHz and 5.8 GHz and improving the radiation gain. Furthermore, by setting the T-type patch 101, the first sub-extension patch 103, the first M-type patch 104, and the second M-type patch 105 in the antenna radiating patch 12, the antenna radiating patch 12 has a symmetrical structure, ensuring the stability of the dual-band radiation of the antenna radiating element 1 at 3.5 GHz and 5.8 GHz. This allows the antenna radiating patch 12 to maintain optimal current distribution and radiation characteristics even when bent, meeting the needs of wearable application scenarios.

[0072] Optional, Figure 4This 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 dual-band radiation of 3.5GHz and 5.8GHz, 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 0.222λ0 and 0.7λ0, the width W of the antenna dielectric substrate 11 along the transverse direction is between 0.187λ0 and 0.327λ0, the length L1 of the T-shaped patch 101 along the longitudinal direction is between 0.033λ0 and 0.064λ0, and the width W9 of the T-shaped patch 101 along the transverse direction is between 0.163λ0 and 0.198λ0. The first grounding feeder 32 and the second grounding feeder 33 have the same dimensions, and the length Lg of the first grounding feeder 32 along the longitudinal direction is between 0.07λ0 and 0.091λ0, the width Wg of the first grounding feeder 32 along the transverse direction is between 0.07λ0 and 0.140λ0, the width W4 of the first sub-extension patch 103 along the transverse direction is between 0.047λ0 and 0.089λ0, and the width W7 of the first opening structure 106 along the transverse direction is between 0.001λ0 and 0.062λ0. The lengths of the first upper oblique line portion 1042 and the second upper oblique line portion 1052 are the same; the lengths of the first upper straight line portion 1043 and the second upper straight line portion 1053 are the same; the lengths of the first lower oblique line portion 1044 and the second lower oblique line portion 1054 are the same; the length W6 of the first upper oblique line portion 1042 is between 0.029λ0 and 0.051λ0; the length W8 of the first upper straight line portion 1043 is between 0.043λ0 and 0.082λ0; and the length W5 of the first lower oblique line portion 1044 is between 0.029λ0 and 0.051λ0.

[0073] at the same time, Figure 5 This is a schematic diagram of another magnetic conductor array reflector provided in an embodiment of this utility model. Figure 5As shown, to ensure that the magnetic conductor array reflector 2 can achieve zero-phase reflection at 3.5GHz and 5.8GHz, 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 dielectric substrate 22 along the lateral direction is between 0.18λ0 and 0.196λ0; the width W1 of the first reflective patch 201 along the lateral direction is between 0.153λ0 and 0.162λ0; and the width W2 of the second reflective patch 202 along the lateral direction is between 0.126λ0 and 0.14λ0. The distance W3 between the two second hollow structures 204 is between 0.006λ0 and 0.07λ0; and the distance r1 between the center point of the second reflective patch 202 and the arc edge of the first semi-circular hollow structure A1 can be between 0.012λ0 and 0.056λ0. 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 dual-band radiation of 3.5GHz and 5.8GHz, λ0 can be determined based on the speed of light and 3.5GHz, that is, the value of λ0 can be 85.7mm. This ensures that the antenna radiation element 1 can achieve dual-band radiation of 3.5GHz and 5.8GHz, and the magnetic conductor array reflector 2 can achieve zero-phase reflection of 3.5GHz and 5.8GHz. This optimizes the radiation gain and security of the dual-band antenna in the dual band, significantly improves the communication reliability, battery life and wearing comfort of the wearable device, and enables the wearable device to adapt to a variety of application scenarios.

[0074] 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 dual-band antenna, the dual-band antenna can achieve dual-band radiation at 3.5 GHz and 5.8 GHz, and achieve zero-phase reflection at 3.5 GHz and 5.8 GHz, the following simulation test can be performed on the dual-band antenna. Figure 6 A 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, the red curve is the total internal reflection characteristic curve of the magnetic conductor array reflector 2, and the black curve is the phase reflection characteristic curve of the magnetic conductor array reflector 2. From the phase reflection characteristic curve, it can be seen that the magnetic conductor array reflector 2 can achieve zero phase reflection at 3.5GHz and 5.8GHz. From the total internal reflection characteristic curve, it can be seen that the reflection coefficient of the magnetic conductor array reflector 2 is -2.29dB at the 3.5GHz frequency and -1.25dB at the 5.8GHz frequency.

[0075] Figure 7 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 7As shown, the equivalent circuit of the magnetic conductor array reflector 2 consists of a free space impedance Z0 with an impedance of 377Ω, an equivalent impedance R1 of the reflective dielectric substrate 22 with an impedance of 214Ω, and two parallel LC resonant branches. The outer ring oscillation circuit is composed of a first capacitor L2 with a capacitance of 0.86nH and a first inductor C1 with an inductance of 2.4pF, which can generate a low-frequency resonance of about 3.5GHz. The inner ring oscillation circuit is composed of a second capacitor L3 with a capacitance of 1.029nH and a second inductor C2 with an inductance of 0.742pF, which can generate a high-frequency resonance of about 5.8GHz. At the same time, the equivalent circuit corrects the phase through a third inductor L1 with a series inductance of 2.9nH. Figure 8 This is a schematic diagram of the reflection characteristic curve of the equivalent circuit of the magnetic conductor array reflector provided in this embodiment of the invention. Figure 8 As can be seen, the blue curve is the reflection characteristic curve of the equivalent circuit, and the red curve is the reflection characteristic curve of the magnetic conductor array reflector 2 in the working frequency band. The two have a high degree of agreement, which verifies the effectiveness of the established circuit model.

[0076] Figure 9 This is a schematic diagram illustrating the effect of rotation on the reflection coefficient of the magnetic conductor array reflector structure provided in an embodiment of the present invention. Figure 9 (a) is a schematic diagram of the structure of the magnetic conductor array reflector 2 rotated. Figure 9 (b) is a graph showing the effect of different rotation angles on the reflection coefficient of the magnetic conductor array reflector 2. Figure 9 (b) It can be seen that, based on the structural symmetry of the magnetic conductor array reflector 2, the center of the magnetic conductor array reflector 2 structure can be rotated by a maximum of ±60°. Under these rotation angles, the magnetic conductor array reflector 2 can still maintain good total reflection characteristics, indicating that the magnetic conductor array reflector 2 has good frequency band stability and robustness.

[0077] Figure 10 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 10 It can be seen that after loading the magnetic conductor array reflector 2, the resonant frequency of the antenna radiating element 1 hardly changes, and the error between the measured result and the simulation result is small, indicating that the antenna radiating element 1 has a good dual-band radiation effect at 3.5GHz and 5.8GHz.

[0078] Figure 11 The normalized far-field radiation pattern of the dual-frequency antenna provided in this embodiment of the present invention, wherein, Figure 11 (a) is the far-field radiation pattern of the dual-band antenna at 3.5 GHz. Figure 11 (b) shows the far-field radiation pattern of the dual-band antenna at 5.8 GHz, derived from... Figure 11 (a) and Figure 11 (b) It can be seen that after loading the magnetic conductor array reflector 2, the difference between the front lobe and the back lobe of the dual-band antenna is greater than 20 dBi at 3.5 GHz and 5.8 GHz. The actual gain at 3.5 GHz increases from 1.415 dBi to 6.151 dBi, and the actual gain at 5.8 GHz increases from 2.312 dBi to 6.988 dBi. This indicates that the dual-band antenna after loading the magnetic conductor array reflector 2 can achieve zero phase reflection at 3.5 GHz and 5.8 GHz, thereby reducing back radiation and enhancing the actual gain.

[0079] Figure 12 The figure shows the simulation results of the specific absorption rate of the dual-band antenna at 3.5 GHz, provided for an embodiment of this utility model. Figure 12 (a) is a graph showing the results of a specific absorption rate simulation of 10g of human tissue. Figure 12 (b) is a graph showing the results of a specific absorption rate simulation of 1g of human tissue. Figure 12 (a) and Figure 12 (b) It can be seen that the specific absorptivity of the dual-frequency antenna at 3.5 GHz is 0.367 W / kg in 1g of human tissue and 0.246 W / kg in 10g of human tissue, which meets the safety standard for specific absorptivity of human tissue. The magnetic conductor array reflector 2 can effectively suppress the back lobe radiation of the dual-frequency antenna and reduce the specific absorptivity of the dual-frequency antenna, thereby reducing the radiation intensity of electromagnetic waves to the human body and ensuring human safety.

[0080] Figure 13 The figure shows the simulation results of the specific absorption rate of the dual-band antenna at 5.8 GHz, provided for an embodiment of this utility model. Figure 13 (a) is a graph showing the results of a specific absorption rate simulation of 10g of human tissue. Figure 13 (b) is a graph showing the results of a specific absorption rate simulation of 1g of human tissue. Figure 13 (a) and Figure 13 (b) It can be seen that the specific absorptivity of the dual-frequency antenna at 3.5 GHz is 0.298 W / kg in 1g of human tissue and 0.149 W / kg in 10g of human tissue, which meets the safety standard for specific absorptivity of human tissue. The magnetic conductor array reflector 2 can effectively suppress the back lobe radiation of the dual-frequency antenna and reduce the specific absorptivity of the dual-frequency antenna, thereby reducing the radiation intensity of electromagnetic waves to the human body and ensuring human safety.

[0081] Based on the same inventive concept, this utility model embodiment also provides a wearable device, which includes the dual-band antenna of the above embodiment.

[0082] Therefore, the wearable device provided in this embodiment has the structure and operation of the dual-band antenna of the above embodiment, and can achieve the effect of the dual-band antenna of the above embodiment. The similarities can be referred to the above description, and will not be repeated here.

[0083] 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 dual-band antenna, 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 above the antenna dielectric substrate; the antenna radiating patch includes at least a T-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 above the reflective dielectric substrate, and a radiation backplate attached below the reflective dielectric substrate; the reflective radiation patch includes a first reflective patch and a second reflective patch spaced apart; the first reflective patch includes a first hollow structure; the second reflective patch is located within the first hollow structure; The second reflective patch includes at least one second 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 dual-band antenna according to claim 1, characterized in that, The second reflective patch includes two second hollow structures that are symmetrically arranged and not connected to each other.

3. The dual-band antenna according to claim 1, characterized in that, The centers of the first reflective patch and the second reflective patch coincide.

4. The dual-band antenna 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 T-shaped patch.

5. The dual-frequency antenna according to claim 4, characterized in that, The antenna radiating patch further includes a first extension patch; The first extension patch is connected between the main feed line and the T-shaped patch.

6. The dual-frequency antenna according to claim 5, characterized in that, The first extension patch includes a first sub-extension patch and a first M-type patch and a second M-type patch located on opposite sides of the first sub-extension patch; The first side of the first sub-extension patch is connected to one end of the T-shaped patch that extends in the longitudinal direction, and the first sub-extension patch is provided with a first opening structure. The second side and the third side of the first sub-extension patch are respectively connected to the first M-type patch and the second M-type patch, and the second side and the third side are both arranged adjacent to the first side; The main feeder is connected to the first M-type patch and the second M-type patch, respectively.

7. The dual-band antenna according to claim 1, characterized in that, The longitudinal length L of the antenna dielectric substrate ranges from 0.222λ0 to L and from 0.7λ0. The width W of the antenna dielectric substrate in the lateral direction ranges as follows: 0.187λ0 < W < 0.327λ0; The value range of the longitudinal length L1 of the T-shaped patch is: 0.033λ0 < L1 < 0.064λ0; The value range of the width W9 of the T-shaped patch along the horizontal direction is: 0.163λ0 < W9 < 0.198λ0; The width Ws of the reflective medium substrate in the transverse direction ranges as follows: 0.18λ0 < Ws < 0.196λ0; The width W1 of the first reflective patch in the lateral direction ranges as follows: 0.153λ0 < W1 < 0.162λ0; The width W2 of the second reflective patch in the lateral direction ranges as follows: 0.126λ0 < W2 < 0.14λ0; λ0 is the wavelength in free space.

8. The dual-frequency antenna according to claim 2, characterized in that, The distance W3 between the two second hollow structures ranges from 0.006λ0 to W3 to 0.07λ0. λ0 is the wavelength in free space.

9. The dual-frequency antenna according to claim 6, characterized in that, The first grounding feeder and the second grounding feeder have the same dimensions; The longitudinal length Lg of the first grounding feeder ranges from 0.07λ0 to Lg to 0.091λ0. The value range of the width Wg of the first grounding feeder in the lateral direction is: 0.07λ0 < Wg < 0.140λ0; The value range of the width W4 of the first sub-extension patch along the lateral direction is: 0.047λ0 < W4 < 0.089λ0; The width W7 of the first opening structure in the transverse direction ranges from 0.001λ0 to W7 to 0.062λ0. λ0 is the wavelength in free space.

10. A wearable device, characterized in that, include: The dual-band antenna as described in any one of claims 1-9.

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