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 pasting its top, the antenna radiation patch includes libra 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, the reflection radiation patch of pasting its top and the radiation backboard of pasting its below, the reflection radiation patch includes first reflection patch and second reflection patch, second reflection patch is located in the hollow structure in first reflection patch, the periphery contour of second reflection patch includes at least two mutually connected circular arc, air layer is located between antenna radiation unit and magnetic conductor array reflection board, and antenna dielectric substrate is located in the air layer far from the one side of reflection radiation patch. 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 healthcare 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, 2.45GHz and 5.8GHz are suitable for both low-power sensing and high-speed data interaction, making them 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 balance-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 hollow structure; the second reflective patch is located within the hollow structure; the outer contour of the second reflective patch includes at least two interconnected arcs; the central angle corresponding to the arcs is greater than 180°.

[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 outer contour of the second reflective patch includes four sequentially connected arc segments.

[0012] Optionally, the hollow structure is a shape formed by stacking a first rectangle and a second rectangle;

[0013] The center points of the first rectangle and the second rectangle do not coincide;

[0014] Each side of the first rectangle intersects with two adjacent sides of the second rectangle, and each side of the second rectangle intersects with two adjacent sides of the first rectangle.

[0015] Optionally, the antenna radiating element further includes a main feed line attached above the antenna dielectric substrate, and a first ground plane and a second ground plane located on opposite sides of the main feed line;

[0016] One end of the main feeder is connected to the scale-shaped patch.

[0017] Optionally, the antenna radiating patch further includes a first extension patch, wherein the first extension patch has a first opening structure.

[0018] The first extension patch is connected between the main feed line and the balance-shaped patch.

[0019] Optionally, the Libra-shaped patch further includes a T-shaped patch, a second extension patch, and a third extension patch; the second extension patch has a second opening structure, and the third extension patch has a third opening structure.

[0020] The second extension patch and the third extension patch are respectively connected to the opposite ends of the T-shaped patch extending in the lateral direction.

[0021] Optionally, the longitudinal length L of the antenna dielectric substrate is in the range of 0.258λ0 < L < 0.328λ0;

[0022] The width W of the antenna dielectric substrate in the lateral direction ranges as follows: 0.147λ0 < W < 0.254λ0;

[0023] The width Ws of the reflective medium substrate in the transverse direction ranges as follows: 0.2λ0 < Ws < 0.205λ0;

[0024] The width W6 of the first reflective patch in the lateral direction ranges as follows: 0.198λ0 < W6 < 0.204λ0;

[0025] λ0 is the wavelength in free space.

[0026] Optionally, the first ground plane and the second ground plane have the same size;

[0027] The longitudinal length Lg of the first ground surface ranges from 0.079λ0 to Lg to 0.097λ0.

[0028] The value range of the width Wg of the first ground surface along the lateral direction is: 0.055λ0 < Wg < 0.108λ0;

[0029] The length L2 of the first extension patch along the longitudinal direction ranges from 0.068λ0 to L2 to 0.089λ0.

[0030] The value range of the width W2 of the first extension patch along the lateral direction is: 0.055λ0 < W2 < 0.197λ0;

[0031] The length L1 of the first opening structure along the longitudinal direction ranges from 0 to L1 to 0.072λ0.

[0032] The width W1 of the first opening structure in the transverse direction ranges from 0.001λ0 to W1 to 0.057λ0.

[0033] λ0 is the wavelength in free space.

[0034] Optionally, the second extension patch and the third extension patch are the same size;

[0035] The longitudinal length L3 of the scale-shaped patch ranges from 0.039λ0 to L3 to 0.072λ0.

[0036] The value range of the width W3 of the horizontal axis of the scale-shaped patch is: 0.045λ0 < W3 < 0.1λ0;

[0037] The value range of the length L4 of the second extension patch along the longitudinal direction is: 0.03λ0 < L4 < 0.041λ0;

[0038] The value range of the width W4 of the second extension patch along the lateral direction is: 0.03λ0 < W4 < 0.052λ0;

[0039] λ0 is the wavelength in free space.

[0040] The second aspect of this utility model provides a wearable device, which includes the dual-band antenna described above.

[0041] 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 balance-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 hollow structure in the first reflective patch, and by defining the outer contour of the second reflective patch as at least two interconnected arcs with a central angle greater than 180°, the first and second reflective patches can respectively form an outer-ring oscillation circuit and an inner-ring oscillation circuit, achieving spatial coupling between them. 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.

[0042] 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

[0043] 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.

[0044] Figure 1 This is a schematic diagram of the structure of a dual-frequency antenna provided in an embodiment of the present invention;

[0045] Figure 2 This is a schematic diagram of the structure of a magnetic conductor array unit provided in an embodiment of the present invention;

[0046] Figure 3 This is a schematic diagram of the structure of an antenna radiating unit provided in an embodiment of this utility model;

[0047] Figure 4 This is a schematic diagram of another antenna radiating element provided in this embodiment of the present invention;

[0048] Figure 5 This is a schematic diagram of another magnetic conductor array reflector provided in this embodiment of the present invention;

[0049] Figure 6 A schematic diagram of the total internal reflection characteristic curve and phase reflection characteristic curve of the magnetic conductor array reflector provided in the embodiment of this utility model;

[0050] Figure 7 A schematic diagram showing the effect curves of different polarized electromagnetic waves and incident angles on the reflection phase characteristics of a magnetic conductor array reflector, provided for embodiments of this utility model.

[0051] 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;

[0052] Figure 9 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;

[0053] Figure 10 A schematic diagram of the bending reflection coefficient curve of a dual-frequency antenna provided in an embodiment of this utility model;

[0054] Figure 11 Normalized far-field radiation pattern of a dual-frequency antenna provided in this embodiment of the present invention;

[0055] Figure 12The simulation results of the specific absorption rate of the dual-band antenna at 2.45 GHz provided in this embodiment of the utility model are shown in the figure.

[0056] 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 present invention are shown in the figure. Detailed Implementation

[0057] 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.

[0058] 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.

[0059] Figure 1 This is a schematic diagram of the structure of a dual-frequency antenna provided in an embodiment of this utility model. Figure 1As 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 balance-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 radiating patch 23 attached above the reflective dielectric substrate 22. And a 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 hollow structure 203; the second reflective patch 202 is located within the hollow structure 203; the outer contour of the second reflective patch 202 includes at least two interconnected arcs; the central angle corresponding to the arc is greater than 180°; 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.

[0060] 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, dual-frequency signals of 2.45GHz 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 2.45GHz 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.

[0061] 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, 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 balance-shaped patch 101, which includes two ends extending laterally and one end extending longitudinally. By setting the balance-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 scale-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 a better current distribution and radiation characteristics when bent.

[0062] 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 2.45GHz 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 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 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.

[0063] 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 hollow structure 203 to form an outer ring oscillation circuit. The geometry of the hollow structure 203, such as the design of its corners, can increase distributed capacitance and inductance, generating low-frequency resonance, thereby enabling zero-phase reflection at 2.45 GHz through the first reflective patch 201. The second reflective patch 202 is located within the hollow structure 203, and its outer contour includes at least two interconnected arcs with a central angle greater than 180°, enabling the formation of an inner ring oscillation circuit through the second reflective patch 202. The arc contour of the second reflective patch 202 with a central angle greater than 180° can form a resonant path similar to a semicircle or ellipse to increase the concentration of the high-frequency electric field, thereby enabling 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 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, 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.

[0064] 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 2.45GHz 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 2.45GHz 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.

[0065] 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 balance-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 hollow structure in the first reflective patch, and by defining the outer contour of the second reflective patch as at least two interconnected arcs with a central angle greater than 180°, the first and second reflective patches can respectively form an outer-ring oscillation circuit and an inner-ring oscillation circuit, achieving spatial coupling between them. 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.

[0066] 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 outer contour of the second reflective patch 202 includes four arc segments connected in sequence.

[0067] Specifically, the outer contour of the second reflective patch 202 may include four arc segments connected in sequence. The four arc segments are connected by a smooth transition to form the outer contour shape of the second reflective patch 202. The four arc segments can selectively form a four-leaf clover structure, which can specifically be represented as a pattern formed by the intersection of four circular patches, thereby producing four symmetrical "leaf lobes" in the four-leaf clover structure. The four circular arcs can specifically include a first arc ρ1, a second arc ρ2, a third arc ρ3, and a fourth arc ρ4. The first reflective patch 201 can be rectangular and can include a first vertex A1 located at the upper left, a second vertex A2 located at the upper right, a third vertex A3 located at the lower left, and a fourth vertex A4 located at the lower right. The first arc ρ1 can be oriented towards the first vertex A1, the second arc ρ2 towards the second vertex A2, the third arc ρ3 towards the third vertex A3, and the fourth arc ρ4 towards the fourth vertex A4, thereby ensuring 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 cloverleaf structure of the second reflective patch 202 can increase the coupling area, thereby expanding the bandwidth and stabilizing the zero-phase reflection point, enabling the second reflective patch 202 to achieve zero-phase reflection at 5.8 GHz.

[0068] Optional, continue to refer to Figure 2 The hollow structure 203 is shaped by stacking a first rectangle 204 and a second rectangle 205; the center points of the first rectangle 204 and the second rectangle 205 coincide; each side of the first rectangle 204 intersects with two adjacent sides of the second rectangle 205, and each side of the second rectangle 205 intersects with two adjacent sides of the first rectangle 204.

[0069] Specifically, the shape of the hollow structure 203 can be a shape formed by stacking the first rectangle 204 and the second rectangle 205. The center points of the first rectangle 204 and the second rectangle 205 coincide, each side of the first rectangle 204 intersects with two adjacent sides of the second rectangle 205, and each side of the second rectangle 205 intersects with two adjacent sides of the first rectangle 204. Therefore, the hollow structure 203 formed by the stacking of the first rectangle 204 and the second rectangle 205 can be octagonal, that is, the hollow structure 203 can include eight sides, namely the first side θ1, the second side θ2, the third side θ3, the fourth side θ4, the fifth side θ5, the sixth side θ6, the seventh side θ7, and the eighth side θ8. The included angle between each side of the first rectangle 204 and the two adjacent sides of the second rectangle 205 that intersect with it can both be 45°, so that the equivalent capacitance and resonant frequency of the magnetic conductor array reflector 2 can be adjusted through the hollow structure 203.

[0070] The hollow structure 203, with its eight corners, increases distributed capacitance and inductance, generating low-frequency resonance, thus enabling zero-phase reflection at 2.45 GHz via the first reflective patch 201. The second reflective patch 202, located within the hollow structure 203, forms an inner-ring oscillation circuit. The clover-shaped structure of the second reflective patch 202 creates a semi-circular or elliptical resonant path, increasing high-frequency electric field concentration, thereby achieving zero-phase reflection at 5.8 GHz via the second reflective patch 202. Simultaneously, the electromagnetic fields generated by the outer and inner ring oscillation circuits are spatially coupled through the hollow structure 203, mutually modulating their resonant frequencies to achieve stable zero-phase reflection at both frequencies using the magnetic conductor array reflector 2. This ensures that the reflected electromagnetic wave is in phase with the incident electromagnetic wave, improving the actual gain of the dual-band radiation. Meanwhile, the symmetrical structure of the first reflective patch 201 and the second reflective patch 202 makes the magnetic conductor array reflector 2 insensitive to electromagnetic waves with different polarization angles incident vertically, and the magnetic conductor array reflector 2 can maintain good performance when electromagnetic waves are incident at different incident angles.

[0071] Optional, Figure 3 This 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 plane 32 and a second ground plane 33 located on opposite sides of the main feed line 31; one end of the main feed line 31 is connected to the balance-type patch 101.

[0072] 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 scale-shaped patch 101, so that the scale-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 2.45GHz and 5.8GHz. The first ground plane 32 and the second ground plane 33 are located on opposite sides of the main feed line 31. The first ground plane 32 and the second ground plane 33 are specifically used as ground 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. In addition, by attaching the main feed line 31, the first ground plane 32, and the second ground plane 33 all above the antenna dielectric substrate 11, the transmission loss of the electrical signal can be reduced through the coplanar waveguide (CPW) feeding method, ensuring that the electrical signal can be efficiently transmitted to the scale-shaped patch 101 to support the high radiation gain of the dual-band. Meanwhile, 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.

[0073] Optional, continue to refer to Figure 3 The antenna radiating patch 12 also includes a first extension patch 102, which has a first opening structure 103. The first extension patch 102 is connected between the main feed line 31 and the scale-shaped patch 101.

[0074] Specifically, the first extension patch 102 is connected between the main feed line 31 and the balance-type 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 balance-type patch 101, thereby further extending the current path in the antenna radiating patch 12. Simultaneously, the first extension patch 102 has a first opening structure 103, which increases the inductance and capacitance effects, assisting in adjusting the resonant frequency of the antenna radiating element 1. The connection between the first extension patch 102 and the balance-type patch 101 increases the physical length and geometric complexity of current propagation. Combined with the modulation effect of the first opening structure 103, this ensures that the antenna radiating element 1 can achieve dual-frequency resonance at 2.45GHz and 5.8GHz, and reduces the reflection coefficient of the antenna radiating element 1 at both frequencies, thereby improving the actual gain.

[0075] Optional, continue to refer to Figure 3The scale-shaped patch 101 includes a T-shaped patch 1011, a second extension patch 104, and a third extension patch 105; the second extension patch 104 has a second opening structure 106, and the third extension patch 105 has a third opening structure 107; the second extension patch 104 and the third extension patch 105 are respectively connected to the opposite ends of the T-shaped patch 1011 extending in the lateral direction.

[0076] Specifically, the second extension patch 104 and the third extension patch 105 are respectively connected to the opposite ends of the T-shaped patch 1011 extending in the lateral direction. The T-shaped patch 1011 is used to extend the current path in the antenna radiating patch 12, and the second extension patch 104 and the third extension patch 105 are used as extensions of the current path of the antenna radiating element 1 to further guide and distribute current, thereby optimizing the dual-frequency resonance of the antenna radiating element 1 at 2.45 GHz and 5.8 GHz. At the same time, the second extension patch 104 is provided with a second opening structure 106, and the third extension patch 105 is provided with a third opening structure 107, so that the inductance and capacitance effects can be further increased through the second opening structure 106 and the third opening structure 107, and the resonant frequency of the antenna radiating element 1 can be adjusted. The second extension patch 104 and the third extension patch 105 extend the current path and, in combination with the modulation effect of the second opening structure 106 and the third opening structure 107, fine-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 2.45 GHz and 5.8 GHz and improving the radiation gain.

[0077] Furthermore, by setting a T-shaped patch 1011, a first extension patch 102, a second extension patch 104, and a third extension patch 105 in the antenna radiating patch 12, the antenna radiating patch 12 has a symmetrical structure, which ensures the stability of the dual-band radiation of the antenna radiating element 1 at 2.45 GHz and 5.8 GHz. This allows the antenna radiating patch 12 to maintain a better current distribution and radiation characteristics when bent, which can meet the needs of wearable application scenarios.

[0078] 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 4As shown, in order to ensure that the antenna radiating element 1 can achieve dual-band radiation of 2.45GHz 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 0.258λ0 and 0.328λ0, and the width W of the antenna dielectric substrate 11 along the transverse direction is between 0.147λ0 and 0.254λ0. The first ground plane 32 and the second ground plane 33 have the same dimensions. The length Lg of the first ground plane 32 along the longitudinal direction is between 0.079λ0 and 0.097λ0, the width Wg of the first ground plane 32 along the transverse direction is between 0.055λ0 and 0.108λ0, the length L2 of the first extension patch 102 along the longitudinal direction is between 0.068λ0 and 0.089λ0, the width W2 of the first extension patch 102 along the transverse direction is between 0.055λ0 and 0.197λ0, the length L1 of the first opening structure 103 along the longitudinal direction is between 0 and 0.072λ0, and the width W1 of the first opening structure 103 along the transverse direction is between 0.001λ0 and 0.057λ0. The second extension patch 104 and the third extension patch 105 have the same dimensions, and the longitudinal length L3 of the T-shaped patch 1011 is between 0.039λ0 and 0.072λ0, the transverse width W3 of the T-shaped patch 1011 is between 0.045λ0 and 0.1λ0, the longitudinal length L4 of the second extension patch 104 is between 0.03λ0 and 0.041λ0, and the transverse width W4 of the second extension patch 105 is between 0.03λ0 and 0.052λ0.

[0079] 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 5 As shown, to ensure that the magnetic conductor array reflector 2 can achieve zero-phase reflection at 2.45 GHz and 5.8 GHz, 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 0.2λ0 and 0.205λ0; the width W6 of the first reflective patch 201 along the lateral direction is between 0.198λ0 and 0.204λ0; the dimensions of the first rectangle 204 and the second rectangle 205 are the same, and the width W7 of the first rectangle 204 along the lateral direction is between 0.114λ0 and 0.132λ0; the side length a of the third angle θ3 can be between 0.022λ0 and 0.034λ0; and the radius r of the circular patch of the second reflective patch 202 forming the cloverleaf structure can be between 0.031λ0 and 0.033λ0. Here, λ0 is the free space wavelength, which can be approximately 3 × 10⁻⁶ based on the speed of light. 8The ratio of m / s and radiation frequency is determined. For example, to achieve dual-band radiation of 2.45 GHz and 5.8 GHz, λ0 can be determined based on the speed of light and 2.45 GHz, that is, the value of λ0 can be 122 mm. This ensures that the antenna radiation element 1 can achieve dual-band radiation of 2.45 GHz and 5.8 GHz, and the magnetic conductor array reflector 2 can achieve zero-phase reflection of 2.45 GHz and 5.8 GHz. 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.

[0080] 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 2.45 GHz and 5.8 GHz, and achieve zero-phase reflection at 2.45 GHz and 5.8 GHz, the following simulation test can be performed on the dual-band antenna. Figure 6 A schematic diagram of the total internal reflection characteristic curve and phase 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 2.45GHz 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 -3.4dB at the 2.45GHz frequency and -2.5dB at the 5.8GHz frequency.

[0081] Figure 7 This is a schematic diagram illustrating the influence of different polarized electromagnetic waves and incident angles on the reflection phase characteristics of a magnetic conductor array reflector, provided in an embodiment of this utility model. Figure 7 (a) 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 (b) is a graph showing the effect of electromagnetic waves at different incident angles on the reflection phase characteristics of the magnetic conductor array reflector 2. Figure 7 (a) It can be seen that when electromagnetic waves with different polarization angles are incident perpendicularly on the magnetic conductor array reflector 2, the phase reflection characteristics of the magnetic conductor array reflector 2 remain unchanged, indicating that the magnetic conductor array reflector 2 has polarization insensitivity characteristics. Figure 7(b) It can be seen that when the incident angle of the incident electromagnetic wave increases from 0° to ±60°, the zero-phase reflection of the magnetic conductor array reflector 2 at the high resonant frequency has a small effect. Compared with the high resonant frequency, the zero-phase reflection of the magnetic conductor array reflector 2 at the low resonant frequency has a slightly more obvious effect, but the reflection frequency is still within the ±90° range, which does not affect the reflection effect of the magnetic conductor array reflector 2 at this frequency. Therefore, the magnetic conductor array reflector 2 has the characteristic of being insensitive to different incident angles of the incident electromagnetic wave.

[0082] 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, the center of the magnetic conductor array reflector 2 structure can be rotated by a maximum of ±45°. Under these rotation angles, the magnetic conductor array reflector 2 can still maintain good total reflection characteristics.

[0083] Figure 9 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 9 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 2.45GHz and 5.8GHz.

[0084] Figure 10 A schematic diagram of the bending reflection coefficient curve of a dual-frequency antenna provided in an embodiment of this utility model. Figure 10 It can be seen that when the dual-band antenna with antenna radiating element 1 and magnetic conductor array reflector 2 is bent along the x-direction (horizontal direction) or y-direction (vertical direction), the reflection coefficient of the dual-band antenna at 2.45GHz and 5.8GHz will move slightly, but it will not affect the overall performance of the dual-band antenna. This shows that the dual-band antenna has good robustness and can maintain better radiation characteristics in the bending state, which can meet the needs of wearable application scenarios.

[0085] 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 2.45 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 2.45 GHz and 5.8 GHz. The actual gain at 2.45 GHz increases from 1.5 dBi to 3.77 dBi, and the actual gain at 5.8 GHz increases from 2.45 dBi to 6.681 dBi. This indicates that the dual-band antenna after loading the magnetic conductor array reflector 2 can achieve zero phase reflection at 2.45 GHz and 5.8 GHz, thereby reducing back radiation and enhancing the actual gain.

[0086] Figure 12 The figure shows the simulated specific absorption rate of the dual-band antenna at 2.45 GHz, as provided in this embodiment of the invention. Figure 12 (a) is a graph showing the results of a specific absorption rate simulation of 1g of human tissue. Figure 12 (b) is a graph showing the results of a specific absorption rate simulation of 10g of human tissue. Figure 12 (a) and Figure 12 (b) It can be seen that the specific absorptivity of the dual-frequency antenna at 2.45 GHz is 0.464 W / kg in 1g of human tissue and 0.234 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.

[0087] 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 1g of human tissue. Figure 13 (b) is a graph showing the results of a specific absorption rate simulation of 10g of human tissue. Figure 13 (a) and Figure 13 (b) It can be seen that the specific absorptivity of the dual-frequency antenna at 2.45 GHz is 0.217 W / kg in 1g of human tissue and 0.101 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.

[0088] 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.

[0089] 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.

[0090] 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 balance-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 hollow structure; the second reflective patch is located within the hollow structure; the outer contour of the second reflective patch includes at least two interconnected arcs; the central angle corresponding to the arcs is greater than 180°. 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 outer contour of the second reflective patch includes four arc segments connected in sequence.

3. The dual-band antenna according to claim 1, characterized in that, The hollow structure is a shape formed by stacking a first rectangle and a second rectangle; The center points of the first rectangle and the second rectangle do not coincide; Each side of the first rectangle intersects with two adjacent sides of the second rectangle, and each side of the second rectangle intersects with two adjacent sides of the first rectangle.

4. The dual-band antenna according to claim 1, characterized in that, The antenna radiating element also includes a main feed line attached above the antenna dielectric substrate, and a first ground plane and a second ground plane located on opposite sides of the main feed line. One end of the main feeder is connected to the scale-shaped patch.

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

6. The dual-band antenna according to claim 1, characterized in that, The Libra-shaped patch includes a T-shaped patch, a second extension patch, and a third extension patch; the second extension patch has a second opening structure, and the third extension patch has a third opening structure. The second extension patch and the third extension patch are respectively connected to the opposite ends of the T-shaped patch extending in the lateral direction.

7. The dual-band antenna according to claim 1, characterized in that, The longitudinal length L of the antenna dielectric substrate is in the range of 0.258λ0 < L < 0.328λ0; The width W of the antenna dielectric substrate in the lateral direction ranges as follows: 0.147λ0 < W < 0.254λ0; The width Ws of the reflective medium substrate in the transverse direction ranges as follows: 0.2λ0 < Ws < 0.205λ0; The width W6 of the first reflective patch in the lateral direction ranges as follows: 0.198λ0 < W6 < 0.204λ0; λ0 is the wavelength in free space.

8. The dual-band antenna according to claim 5, characterized in that, The first ground plane and the second ground plane have the same dimensions; The longitudinal length Lg of the first ground surface ranges from 0.079λ0 to Lg to 0.097λ0. The value range of the width Wg of the first ground surface along the lateral direction is: 0.055λ0 < Wg < 0.108λ0; The length L2 of the first extension patch along the longitudinal direction ranges from 0.068λ0 to L2 to 0.089λ0. The value range of the width W2 of the first extension patch along the lateral direction is: 0.055λ0 < W2 < 0.197λ0; The length L1 of the first opening structure along the longitudinal direction ranges from 0 to L1 to 0.072λ0. The width W1 of the first opening structure in the transverse direction ranges from 0.001λ0 to W1 to 0.057λ0. λ0 is the wavelength in free space.

9. The dual-frequency antenna according to claim 6, characterized in that, The second extension patch and the third extension patch are the same size; The longitudinal length L3 of the T-shaped patch ranges from 0.039λ0 to L3 to 0.072λ0. The value range of the width W3 of the T-shaped patch along the horizontal direction is: 0.045λ0 < W3 < 0.1λ0; The value range of the length L4 of the second extension patch along the longitudinal direction is: 0.03λ0 < L4 < 0.041λ0; The value range of the width W4 of the second extension patch along the lateral direction is: 0.03λ0 < W4 < 0.052λ0; 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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