Low-profile miniaturized dual-band antenna based on LC resonance loading

Abstract

The invention provides a low-profile miniaturized dual-band antenna based on LC resonance loading, and relates to the technical field of microstrip antenna structure design, the low-profile miniaturized dual-band antenna comprises a metal floor, a dielectric plate, a radiation structure, an LC resonance structure and a feed structure, the dielectric plate is fixedly arranged right above the metal floor; the radiation structure is arranged right above the dielectric plate, the radiation structure is composed of a plurality of coaxial metal circular patches, and a plurality of through holes are formed in the radiation structure; the LC resonance structure is arranged in the through hole of the radiation structure; the feed structure is arranged on the center line of the radiation structure, and the top end of the feed structure passes through the dielectric plate and is connected with the radiation structure. The problems of miniaturization and low profile of a traditional low-frequency antenna are solved, the size is remarkably reduced, and meanwhile the dual-band working capacity and good radiation performance are maintained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of microstrip antenna structure design, in particular to a low-profile miniaturized dual-band antenna based on LC resonance loading. BACKGROUND

[0002] With the rapid development of modern communication technology, the requirements of communication systems for antennas are becoming higher and higher, not only covering a wider frequency band, but also having higher spectral efficiency and stronger anti-interference ability, and the miniaturization of antennas has become a key technique to meet the needs of modern portable and space-limited platforms. Multi-band antennas, which can work in multiple frequency bands at the same time, meet this demand.

[0003] Currently, the implementation methods of multi-band antennas mainly include slotting on the patch and multi-layer dielectric stacking. To achieve vertical polarization, the antenna profile will be too high, making it difficult to install. If you want to achieve resonance at low frequencies, the size of the antenna will increase, increasing the installation space of the antenna.

[0004] From the current design method of multi-band antennas, if you need to meet multiple frequency bands and vertical polarization at the same time, you mostly use multi-layer dielectric stacking, slotting, etc. Although multi-layer dielectric stacking can produce multiple resonance points, this method will increase the number of antenna layers, inevitably increasing the profile height of the antenna. Slotting on the ground plane with different lengths or shapes can make itself or its combination with the radiating patch resonate at multiple specific frequencies, allowing the antenna to achieve multi-band. However, after slotting on the ground plane, the antenna cannot be installed on the metal ground plane. At the same time, if the antenna wants to achieve resonance at low frequencies, it will generally increase the horizontal size and profile height of the antenna, which will increase the volume of the antenna, making it difficult to install in space-limited situations.

[0005] Therefore, there is an urgent need for a low-profile miniaturized dual-band antenna based on LC resonance loading to solve the above technical problems. SUMMARY

[0006] The present application relates to the technical field of microstrip antenna structure design, in particular to a low-profile miniaturized dual-band antenna based on LC resonance loading. In a first aspect, the application provides a low-profile miniaturized dual-band antenna based on LC resonance loading, comprising: a metal floor, a dielectric plate, a radiation structure, an LC resonance structure and a feed structure, the dielectric plate is fixedly arranged above the metal floor; the radiation structure is arranged above the dielectric plate, the radiation structure is composed of multiple coaxial metal circular patches, and multiple through holes are arranged on the radiation structure; the LC resonance structure is arranged in the through hole of the radiation structure; the feed structure is arranged on the center line of the radiation structure, and the top end of the feed structure penetrates through the dielectric plate and is connected with the radiation structure.

[0007] Optionally, the dielectric constant of the dielectric plate is 2.2 and the loss tangent is 0.003.

[0008] Optionally, the radiation structure comprises a central circular radiation patch, a first circular ring patch, a second circular ring patch and a third circular ring patch, the central circular radiation patch, the first circular ring patch, the second circular ring patch and the third circular ring patch are all attached to the upper surface of the dielectric plate, the central circular radiation patch is connected with the feed structure, the third circular ring patch is sleeved outside the central circular radiation patch, the second circular ring patch is arranged between the central circular radiation patch and the third circular ring patch, and the first circular ring patch is arranged between the central circular radiation patch and the second circular ring patch.

[0009] Optionally, the thicknesses of the central circular radiation patch, the first circular ring patch, the second circular ring patch and the third circular ring patch are the same, and the central axes of the central circular radiation patch, the first circular ring patch, the second circular ring patch and the third circular ring patch are located at the same position.

[0010] Optionally, circular ring gaps are arranged between the central circular radiation patch, the first circular ring patch, the second circular ring patch and the third circular ring patch in pairs.

[0011] Optionally, at least six through holes are arranged on the first circular ring patch and the third circular ring patch, one LC resonance structure is arranged in each through hole, and the LC resonance structure is fixedly connected with the inner wall of the corresponding through hole.

[0012] Optionally, the LC resonance structure comprises a central circular pad, a short-circuit column inductor and a capacitor patch, the central circular pad is fixedly arranged on the dielectric plate, the central axis of the central circular pad and the central axis of the through hole are located on the same line, a circular ring gap is arranged between the central circular pad and the through hole, the central circular pad and the through hole are connected through the capacitor patch, and the two ends of the short-circuit column inductor penetrate through the dielectric plate and are connected with the central circular pad and the metal floor respectively.

[0013] Optionally, the short-circuit column inductor is a metal column.

[0014] Optionally, the feeding structure comprises a stepped feeding column and a coaxial feeding connector, a top end of the stepped feeding column is connected with a center point of the radiating structure, and a bottom end of the stepped feeding column is connected with a top end of the coaxial feeding connector through the metal ground plate.

[0015] Optionally, the stepped feeding column is arranged in a stepped manner, and the diameter of the stepped feeding column is arranged to decrease from top to bottom.

[0016] The present application has the following beneficial effects: The present application provides a low-profile dual-band miniaturized vertical polarization microstrip antenna loaded with a short-circuit column inductor and a patch capacitor, which realizes the reduction of the overall size while ensuring vertical polarization, and the antenna profile height is only 0.0283 lambda, and the present application is made of a single-layer structure, which can effectively reduce the profile height of the antenna, reduce the complexity of the antenna manufacturing, improve the stability of the antenna, overcome the problems of miniaturization and low profile of the traditional low-frequency antenna, and maintain the dual-band working ability and good radiation performance while significantly reducing the size.

[0017] Other features and advantages of the present application will be described in the following specification, and some will become apparent from the specification, or will be understood from the practice of the application. The purpose and other advantages of the present application can be achieved and obtained by the structure specifically pointed out in the written specification, claims, and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0019] Figure 1 It is a top view schematic diagram of the low-profile miniaturized dual-band antenna based on LC resonance loading described in the embodiments of the present application; Figure 2 It is a top view schematic diagram of the low-profile miniaturized dual-band antenna based on LC resonance loading described in the embodiments of the present application; Figure 1 It is an enlarged schematic diagram of A in the figure; Figure 3 It is a sectional view schematic diagram along the center line of the low-profile miniaturized dual-band antenna based on LC resonance loading described in the embodiments of the present application; Figure 4 It is a sectional view schematic diagram along the center line of the low-profile miniaturized dual-band antenna based on LC resonance loading described in the embodiments of the present application; Figure 3 It is an enlarged schematic diagram of B in the figure; Figure 5The antenna's E-plane radiation pattern at 0.851 GHz is shown. Figure 6 The antenna's H-plane radiation pattern at 0.851 GHz is shown. Figure 7 The antenna's E-plane radiation pattern at 1.8 GHz is shown. Figure 8 The antenna's H-plane radiation pattern is shown at 1.8 GHz.

[0020] The markings in the diagram are: 1. Metal ground plane; 2. Dielectric board; 3. Central circular radial patch; 4. First circular patch; 5. Second circular patch; 6. Third circular patch; 7. Central circular pad; 8. Short-circuit post inductor; 9. Capacitor patch; 10. Coaxial feed connector; 11. Stepped feed post. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0022] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this invention, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0023] Example 1:

[0024] This embodiment provides a low-profile miniaturized dual-band antenna based on LC resonant loading.

[0025] See Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 7 and Figure 8The figure shows a low-profile miniaturized dual-band antenna based on LC resonant loading, including: a metal ground plate 1, a dielectric substrate 2, a radiating structure, an LC resonant structure, and a feeding structure. The dielectric substrate 2 is fixedly disposed above the metal ground plate 1; the radiating structure is disposed above the dielectric substrate 2, and the radiating structure is composed of multiple coaxial circular metal patches with multiple through holes; the LC resonant structure is disposed within the through holes of the radiating structure; the feeding structure is disposed on the center line of the radiating structure, and the top end of the feeding structure passes through the dielectric substrate 2 and connects to the radiating structure.

[0026] It is understood that the present invention innovatively integrates a three-layer functional structure for a low-profile miniaturized dual-band antenna based on LC resonant loading: the bottom all-metal floor 1 provides complete grounding and electromagnetic shielding, ensuring that the antenna can be directly installed on a metal carrier (such as a vehicle platform); the dielectric substrate 2 above it achieves an ultra-low profile design of 0.0283λ, which reduces the vertical space occupation compared with the traditional structure; the upper surface of the dielectric substrate 2 forms a rotationally symmetrical radiating structure - the central circular patch 3 and the triple concentric ring patch constitute a multi-resonant unit, which excites dual-band omnidirectional coverage by controlling the size gradient of the annular gap.

[0027] Optionally, the dielectric constant of the dielectric substrate 2 is 2.2 and the loss tangent is 0.003.

[0028] It is understood that the dielectric constant of the present invention is 2.2 and the loss tangent is 0.003, which can reduce the surface wave excitation intensity, improve the radiation efficiency, and suppress the thermal loss of the dielectric.

[0029] Optionally, the radiating structure includes a central circular radiating patch 3, a first annular patch 4, a second annular patch 5, and a third annular patch 6. The central circular radiating patch 3, the first annular patch 4, the second annular patch 5, and the third annular patch 6 are all attached to the upper surface of the dielectric substrate 2. The central circular radiating patch 3 is connected to the feeding structure. The third annular patch 6 is sleeved outside the central circular radiating patch 3. The second annular patch is disposed between the central circular radiating patch 3 and the third annular patch 6. The first annular patch 4 is disposed between the central circular radiating patch 3 and the second annular patch 5.

[0030] It is understood that the radiation structure of the present invention adopts a four-level nested design to achieve compact dual-frequency resonance: the central circular radiation patch 3 is directly connected to the feeding structure as the main excitation source, and the outer periphery is nested in sequence with the first circular patch 4 (loading LC resonant structure), the second circular patch 5 (for extending high frequency bandwidth) and the third circular patch 6 (for extending low frequency current path). The three are isolated by annular gap to form gradient capacitive coupling. This coaxial arrangement combined with rotational symmetry layout can separate the resonant frequency by adjusting the size gradient and achieve 360° omnidirectional coverage.

[0031] Optionally, the central circular radiating patch 3, the first annular patch 4, the second annular patch 5, and the third annular patch 6 have the same thickness, and their central axes are located at the same position.

[0032] It is understood that the thickness uniformity in this invention avoids the distortion of current distribution caused by material thickness differences between patches, while simplifying the manufacturing process; secondly, the strict coaxial layout enhances rotational symmetry and ensures uniform current radiation in the horizontal plane.

[0033] Optionally, each of the central circular radiating patch 3, the first annular patch 4, the second annular patch 5, and the third annular patch 6 has annular gaps between each other.

[0034] It is understood that the present invention adjusts the receiving frequency band by setting the width of the annular gap.

[0035] Optionally, both the first annular patch 4 and the third annular patch 6 are provided with at least six through holes, and each through hole is provided with an LC resonant structure, which is fixedly connected to the inner wall of its corresponding through hole.

[0036] It is understood that the present invention constructs an LC resonant circuit, which, while ensuring a low profile, excites new resonant points in the low-frequency band, effectively realizing the miniaturization of the antenna.

[0037] Optionally, the LC resonant structure includes a central circular pad 7, a short-circuit post inductor 8, and a capacitor patch 9. The central circular pad 7 is fixedly disposed on the dielectric substrate 2. The central axis of the central circular pad 7 and the central axis of the through hole are located on the same straight line. An annular gap is provided between the central circular pad 7 and the through hole. The central circular pad 7 and the through hole are connected by the capacitor patch 9. The two ends of the short-circuit post inductor 8 pass through the dielectric substrate 2 and are respectively connected to the central circular pad 7 and the metal ground plate 1.

[0038] It is understood that the present invention constructs an LC resonant circuit by loading a capacitor patch 9 and a short-circuit post inductor 8 structure onto a conventional circular ring slot coupled antenna. At the same time, multiple circular ring patches work together to generate multiple resonant points. By adjusting the patch size, the antenna can achieve dual-band coverage.

[0039] Optionally, the short-circuit post inductor 8 is a metal post.

[0040] Understandably, the metal shorting post 8 can increase the effective inductance of the antenna, and the capacitor loaded between the circular pad and the ring patch can increase the effective capacitance of the antenna.

[0041] Optionally, the power supply structure includes a stepped power supply column 11 and a coaxial power supply connector 10. The top end of the stepped power supply column 11 is connected to the center point of the radiation structure, and the bottom end of the stepped power supply column 11 passes through the metal floor 1 and is connected to the top end of the coaxial power supply connector 10.

[0042] It is understandable that the geometric center point of the central circular patch 3 is welded to the top of the stepped feed column 11 in this step, so as to ensure that the bottom end of the rotationally symmetric current excitation passes through the metal floor 1 and is connected to the inner conductor of the coaxial feed connector 10 to form a continuous conductive path.

[0043] Optionally, the stepped power supply column 11 is arranged in a stepped shape, and the diameter of the stepped power supply column 11 is set to decrease from top to bottom.

[0044] It is understood that the antenna in this step uses a coaxial feed connector 10 located in the center, and a stepped feed post 11 is loaded on the inner core of the coaxial feed connector 10 to optimize the impedance matching of the antenna.

[0045] It should be noted that the specific manner in which each module performs its operation in the apparatus described in the above embodiments has been described in detail in the embodiments of the method, and will not be elaborated here.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A low-profile miniaturized dual-band antenna based on LC resonant loading, characterized in that, include: Metal floor (1); Medium plate (2), the medium plate (2) is fixedly installed directly above the metal floor (1); The radiating structure is located directly above the dielectric substrate (2). The radiating structure is composed of multiple coaxial metal circular patches and has multiple through holes. An LC resonant structure is disposed within the through-hole of the radiating structure; A power supply structure is provided, which is located on the center line of the radiation structure, and the top end of the power supply structure passes through the dielectric plate (2) and is connected to the radiation structure.

2. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 1, characterized in that, include: The dielectric constant of the dielectric substrate (2) is 2.2 and the loss tangent is 0.

003.

3. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 1, characterized in that, include: The radiation structure includes a central circular radiation patch (3), a first annular patch (4), a second annular patch (5), and a third annular patch (6). The central circular radiation patch (3), the first annular patch (4), the second annular patch (5), and the third annular patch (6) are all attached to the upper surface of the dielectric substrate (2). The central circular radiation patch (3) is connected to the power feeding structure. The third annular patch (6) is sleeved on the outside of the central circular radiation patch (3). The second annular patch is disposed between the central circular radiation patch (3) and the third annular patch (6). The first annular patch (4) is disposed between the central circular radiation patch (3) and the second annular patch (5).

4. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 3, characterized in that, include: The central circular radiating patch (3), the first annular patch (4), the second annular patch (5), and the third annular patch (6) have the same thickness, and their central axes are located at the same position.

5. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 3, characterized in that, include: The central circular radiating patch (3), the first circular patch (4), the second circular patch (5), and the third circular patch (6) are all provided with circular gaps between each other.

6. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 3, characterized in that, include: Both the first annular patch (4) and the third annular patch (6) are provided with at least six through holes, and each through hole is provided with an LC resonant structure, which is fixedly connected to the inner wall of its corresponding through hole.

7. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 6, characterized in that, include: The LC resonant structure includes a central circular pad (7), a short-circuit post inductor (8), and a capacitor patch (9). The central circular pad (7) is fixedly disposed on the dielectric substrate (2). The central axis of the central circular pad (7) and the central axis of the through hole are on the same straight line. An annular gap is provided between the central circular pad (7) and the through hole. The central circular pad (7) and the through hole are connected by the capacitor patch (9). The two ends of the short-circuit post inductor (8) pass through the dielectric substrate (2) and are connected to the central circular pad (7) and the metal ground plate (1), respectively.

8. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 7, characterized in that, include: The short-circuit column inductor (8) is a metal column.

9. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 1, characterized in that, include: The power supply structure includes a stepped power supply column (11) and a coaxial power supply connector (10). The top end of the stepped power supply column (11) is connected to the center point of the radiation structure, and the bottom end of the stepped power supply column (11) passes through the metal floor (1) and is connected to the top end of the coaxial power supply connector (10).

10. The low-profile miniaturized dual-band antenna based on LC resonant loading according to claim 9, characterized in that, include: The stepped power supply column (11) is arranged in a stepped shape, and the diameter of the stepped power supply column (11) is set to decrease from top to bottom.

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