A system ground plane integrated quasi-isotropic antenna based on antenna booster

Abstract

The present invention discloses a quasi-isotropic antenna integrated with a system ground plane based on an antenna booster. The antenna comprises a dielectric substrate, a first metal layer disposed on the upper surface of the dielectric substrate, and a second metal layer disposed on the lower surface of the dielectric substrate. The first metal layer is provided with a first metal ground plane, an antenna booster, and a matching network. The second metal layer is provided with a second metal ground plane. The first and second metal ground planes are provided with first and second clearance areas, respectively. The first and second metal ground planes are short-circuited by first and second metal vias. The present invention utilizes the antenna booster to stimulate the radiation pattern of the system ground plane, with the system ground plane providing an equivalent λ / 4U-shaped radiator, thereby achieving quasi-isotropic radiation. This solves the technical problem of existing quasi-isotropic antennas being unable to maintain good radiation performance in the presence of a system ground plane.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave antennas, and in particular relates to a system ground plane integrated quasi-isotropic antenna based on an antenna enhancer. Background Art

[0002] The Internet of Things (IoT) has been a hot topic in recent years. As more and more devices join IoT networks, the random orientation and relative positions of wireless devices present new challenges for antenna design. Practical quasi-isotropic antennas, which achieve near-isotropic radiation performance, are ideal for these applications. Quasi-isotropic antennas offer zero-null radiation coverage across the entire three-dimensional space.

[0003] Currently, there are four main methods for achieving quasi-isotropic radiation. The first method arranges multiple discrete elements in a circular array, with each element radiating a specific spatial angle, so that the entire array achieves full spatial coverage. The second method involves combining multiple electric dipoles or monopoles to synthesize a quasi-isotropic radiation pattern. The third method, based on the concept of complementary antennas, feeds a pair of orthogonal electric and magnetic dipoles with signals of equal amplitude and orthogonal phase to achieve complementary null points in the radiation pattern, thereby achieving quasi-isotropic radiation. The fourth method utilizes a λ / 4 U-shaped radiator structure to achieve quasi-isotropic radiation. However, most existing designs overlook a crucial factor: the system ground plane in wireless devices. When a system ground plane is present, induced currents in the ground plane can disrupt the antenna's radiation characteristics. However, the presence of a system ground plane is unavoidable in practical applications.

[0004] Therefore, it is urgent to design an antenna that can still achieve good quasi-isotropic radiation performance in the presence of a system ground plane. Summary of the Invention

[0005] The present invention aims to address the shortcomings of the prior art by providing a system ground plane integrated quasi-isotropic antenna. This antenna can achieve good quasi-isotropic radiation performance even in the presence of a system ground plane, achieving a gain variation of 3.66 dB at 2.45 GHz.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A system ground plane integrated quasi-isotropic antenna based on an antenna booster comprises a dielectric substrate, a first metal layer arranged on the upper surface of the dielectric substrate, and a second metal layer arranged on the lower surface of the dielectric substrate;

[0008] A first metal ground plane, an antenna booster, and a matching network are provided on the first metal layer; a second metal ground plane is provided on the second metal layer; and a penetrating feed via is provided on the dielectric substrate;

[0009] A first clearance area and a second clearance area are respectively provided on the first metal grounding surface and the second metal grounding surface;

[0010] The first metal ground plane and the second metal ground plane are short-circuited by a plurality of first metal vias and a plurality of second metal vias; the plurality of first metal vias are arranged around the edge of the dielectric substrate, and the plurality of second metal vias are arranged around the matching network;

[0011] The matching network includes a first matching element, a second matching element, a third matching element, a transverse microstrip line, a first longitudinal microstrip line, and a second longitudinal microstrip line; the feeding via is opened at one end of the transverse microstrip line, the other end of the transverse microstrip line is connected to one end of the first longitudinal microstrip line through the first matching element, the other end of the first longitudinal microstrip line is connected to one end of the second longitudinal microstrip line through the second matching element, and the other end of the second longitudinal microstrip line is connected to one end of the antenna enhancer.

[0012] In the above technical solution, the antenna enhancer is a bent metal strip, which is arranged in the first clearance area. The bent end of the antenna enhancer is connected to the second longitudinal microstrip line, and the other end does not contact the edge of the first clearance area, and a gap D is set.

[0013] In the above technical solution, the first clearance area and the second clearance area have the same size and are respectively opened at the center position of the corresponding sides of the first metal grounding surface and the second metal grounding surface.

[0014] In the above technical solution, an annular groove is provided outside the feeding via, and the annular groove is provided in the second metal grounding surface.

[0015] In the above technical solution, the first matching element and the second matching element are chip inductors, and the third matching element is a chip capacitor, and both adopt a 0402 package size.

[0016] In the above technical solution, the transverse microstrip line is chamfered.

[0017] In the above technical solution, the widths of the transverse microstrip line, the first longitudinal microstrip line and the second longitudinal microstrip line are the same.

[0018] In the above technical solution, the gaps between the transverse microstrip line, the first longitudinal microstrip line, the second longitudinal microstrip line and both sides of the first metal ground plane are set to be of equal width.

[0019] In the above technical solution, the material of the dielectric substrate is FR4 material, which has a dielectric constant of approximately 4.4 and a loss tangent of approximately 0.02.

[0020] In the above technical solution, the dielectric substrate, the first metal ground plane, and the second metal ground plane have the same size.

[0021] In the above technical solution, the first metal via and the second metal via have the same aperture.

[0022] Working principle of the present invention:

[0023] By exciting the radiation pattern of the system ground plane through the antenna enhancer, the current distribution on the system ground plane can be equivalent to a λ / 4U-type radiator, thereby realizing a quasi-isotropic radiation pattern. This method replaces the traditional resonant antenna element with a non-self-resonant element, effectively transforming the system ground plane, which is traditionally used as a reference plane, into the main radiator. The functional integration of the system ground plane and the radiating element is realized, which can fundamentally eliminate the fatal influence of the system ground plane on the quasi-isotropic radiation performance of the antenna in the traditional design. In addition, the radiation system without a matching network does not achieve good impedance matching, so a matching network is introduced. In the present invention, the matching network not only plays a role in optimizing impedance matching, but also plays a role in adjusting the operating frequency band.

[0024] In summary, in the present invention, the combination of the antenna booster, the system ground plane and the matching network forms a quasi-isotropic antenna with excellent performance.

[0025] Compared with the prior art, the advantages of the present invention are as follows:

[0026] (1) The antenna proposed in the present invention still achieves good quasi-isotropic radiation performance in the presence of a system ground plane. Non-self-resonant elements are used instead of traditional resonant antenna elements, breaking through the limitation of traditional antennas that rely on resonant characteristics to achieve radiation, allowing the antenna to operate in a wider frequency band, thereby improving the applicability and flexibility of the antenna. The system ground plane is used as the main radiator, realizing the functional integration of the system ground plane and the radiating element, making the antenna structure more compact and smaller in size, and fundamentally eliminating the adverse effects of the system ground plane on the quasi-isotropic radiation performance in traditional designs.

[0027] (2) The antenna proposed in the present invention excites the radiation pattern of the system ground plane through the antenna booster, and the system ground plane provides an equivalent λ / 4U-shaped radiator to achieve quasi-isotropic radiation.

[0028] (3) The antenna proposed in the present invention adopts a planar structure, which is more convenient for integration with wireless devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the three-dimensional structure of the ground plane integrated quasi-isotropic antenna of the designed system;

[0030] Figure 2 This is a schematic diagram of the two-dimensional structure of the upper surface of the ground plane integrated quasi-isotropic antenna of the designed system;

[0031] Figure 3 This is a schematic diagram of the two-dimensional structure of the lower surface of the ground plane integrated quasi-isotropic antenna of the designed system;

[0032] Figure 4 This is a two-dimensional partial enlarged view of the upper surface of the ground plane integrated quasi-isotropic antenna of the designed system;

[0033] Figure 5 This is a stacking diagram of the ground plane integrated quasi-isotropic antenna of the designed system;

[0034] Figure 6 This is the simulation of the ground plane integrated quasi-isotropic antenna of the designed system|S 11 |And gain change result graph;

[0035] Figure 7 This is the simulation radiation efficiency result diagram of the ground plane integrated quasi-isotropic antenna of the designed system;

[0036] Figure 8 This is the simulated 2.45GHz two-dimensional normalized gain diagram of the designed system's ground plane integrated quasi-isotropic antenna.

[0037] Markings in the figure: 1-dielectric substrate; 2-first metal ground plane; 3-antenna booster; 4-first metal via; 5-feed via; 6-second metal via; 7-second metal ground plane; 8-annular groove; 9-matching network; 91-first matching element; 92-second matching element; 93-third matching element; 94-transverse microstrip line; 95-first longitudinal microstrip line; 96-second longitudinal microstrip line; 10-first metal layer; 11-second metal layer; 12-first clearance area; 13-second clearance area. DETAILED DESCRIPTION

[0038] In order to better illustrate the technical solutions, design objectives and advantages of the present invention, the present invention will be described in detail with reference to the embodiments and drawings. The specific embodiments used herein are for illustration only and are not intended to limit the present invention.

[0039] In the introduction to the embodiments of the present invention, it should be noted that the terms "first," "second," etc., are used solely for descriptive convenience and are not to be construed as limitations of the present invention. Furthermore, the terms "longitudinal," "transverse," "upper," "lower," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the embodiments of the present invention. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they are not to be construed as limitations of the embodiments of the present invention.

[0040] like Figure 1-Figure 5 The illustrated system ground plane integrated quasi-isotropic antenna based on an antenna booster includes a dielectric substrate 1, a first metal layer 10 disposed on the upper surface of the dielectric substrate 1, and a second metal layer 11 disposed on the lower surface of the dielectric substrate 1. A first metal ground plane 2, an antenna booster 3, and a matching network 9 are disposed on the first metal layer 10; a second metal ground plane 7 is disposed on the second metal layer 11. Feed vias 5 are provided through the dielectric substrate 1. First and second clearance areas 12 and 13 are defined in the first and second metal ground planes 2 and 7, respectively. The first and second metal ground planes 2 and 7 are short-circuited by a plurality of first metal vias 4 and a plurality of second metal vias 6. The plurality of first metal vias 4 are disposed around the edge of the dielectric substrate 1, and the plurality of second metal vias 6 are disposed around the matching network 9.

[0041] The matching network 9 includes a first matching element 91 , a second matching element 92 , a third matching element 93 , a transverse microstrip line 94 , a first longitudinal microstrip line 95 , and a second longitudinal microstrip line 96 . The antenna booster 3 is a bent metal strip, and is disposed in the first clearance area 12 .

[0042] The other end of the antenna booster 3 is not in contact with the first metal ground plane 2. An annular groove 8 is formed outside the feeding via 5.

[0043] The dielectric substrate 1 has a thickness of H1 = 1 mm, and the first metal layer 10 and the second metal layer 11 have thicknesses of H2 = 0.035 mm. The dielectric substrate 1, the first metal ground plane 2, and the second metal ground plane 7 all have dimensions of L1×W1 = 66 mm×31 mm.

[0044] Furthermore, the first clearance area 12 and the second clearance area 13 have the same size and are respectively opened at the center position of the corresponding sides on the first metal ground plane 2 and the second metal ground plane 7. The size is L2×W2=12.1mm×11mm. The length of the longitudinal part of the antenna enhancer 3 set on the first metal layer 10 is L3=9.7mm, and the width is W3=3.3mm. The gap D=0.2mm between the antenna enhancer 3 and the upper edge of the first clearance area 12, and the gap D1=1.1mm between the antenna enhancer 3 and the lower edge of the first clearance area 12. Furthermore, the length of the transverse part of the antenna enhancer 3 is L4=8.6mm, and the width is W4=1.5mm. The bent end of the antenna enhancer is connected to the second longitudinal microstrip line 96.

[0045] Furthermore, the matching network 9 includes a first matching element 91, a second matching element 92, a third matching element 93, a transverse microstrip line 94, a first longitudinal microstrip line 95, and a second longitudinal microstrip line 96. The feed via 5 is provided at one end of the transverse microstrip line 94. The other end of the transverse microstrip line 94 is connected to one end of the first longitudinal microstrip line 95 via the first matching element 91. The other end of the first longitudinal microstrip line 95 is connected to one end of the second longitudinal microstrip line 96 via the second matching element 92. The other end of the second longitudinal microstrip line 96 is connected to the bent end of the antenna booster 3. The first and second matching elements 91, 92 are chip inductors, and the third matching element 93 is a chip capacitor. Both utilize a 0402 package size. The transverse microstrip line 94 is chamfered. The transverse microstrip line 94, the first longitudinal microstrip line 95, and the second longitudinal microstrip line 96 have the same width, W5 = 1.5 mm. The lengths of the transverse microstrip line 94 and the first longitudinal microstrip line 95 are L7 = 4.5 mm and L6 = 2 mm, respectively. The combined length of the second longitudinal microstrip line 96 and the end of the antenna booster 3 is L5 = 4.1 mm. The transverse microstrip line 94, the first longitudinal microstrip line 95, and the second longitudinal microstrip line 96 are spaced equally from the first metal ground plane 2, with the gap being set to 0.5 mm.

[0046] Furthermore, the first metal via 4 and the second metal via 6 have the same diameter, R1 = 0.4mm. The feed via 5 has a diameter of R2 = 0.63mm. The annular groove 8 provided outside the feed via 5 has a diameter of R3 = 1.68mm. The feed system uses a coaxial backfeed method. The feed via 5 passes through the substrate to connect to the matching network. The annular groove 8 is provided on the periphery to isolate the inner and outer conductors, ensuring feed reliability and preventing short circuits between the inner and outer conductors of the coaxial feed line.

[0047] Figure 6 For the simulation of this embodiment |S 11The gain variation results graph shows that the optimized matching network 9 has a -10dB impedance bandwidth covering the 2.36GHz to 2.54GHz frequency band, with a designed center operating frequency of 2.45GHz. Furthermore, the gain variation is less than -6dB across the entire -10dB impedance bandwidth. Specifically, the gain variation is no greater than 4.5dB across the entire -10dB impedance bandwidth.

[0048] Figure 7 This is a diagram showing the simulated radiation efficiency results of this embodiment. It can be seen that a good radiation efficiency of over 85% is achieved within the entire -10dB impedance bandwidth.

[0049] In order to more intuitively demonstrate the achieved quasi-isotropic radiation, Figure 8 A simulated two-dimensional normalized gain plot at 2.45 GHz is shown. This example demonstrates relatively uniform quasi-isotropic radiation at 2.45 GHz, with a gain variation of 3.66 dB at 2.45 GHz. These data demonstrate the significant application value of the antenna in IoT devices and other scenarios, providing a new technical approach for integrating quasi-isotropic antennas into system ground planes.

[0050] The above is only one embodiment of the present invention and is only used to help understand the method and core idea of ​​the present invention. It should be pointed out that for those skilled in the art, without departing from the principles of the present invention, the present invention can also be improved, and these improvements will also fall within the scope of protection of the claims of the present invention. The present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations conceived by the present invention are protected.

Claims

1. A system ground plane integrated quasi-isotropic antenna based on an antenna booster, comprising a dielectric substrate (1), a first metal layer (10) arranged on the upper surface of the dielectric substrate (1), and a second metal layer (11) arranged on the lower surface of the dielectric substrate (1); characterized in that: A first metal ground plane (2), an antenna booster (3), and a matching network (9) are provided on the first metal layer (10); a second metal ground plane (7) is provided on the second metal layer (11); and a penetrating feed via (5) is provided on the dielectric substrate (1); The matching network (9) includes a first matching element (91), a second matching element (92), a third matching element (93), a transverse microstrip line (94), a first longitudinal microstrip line (95), and a second longitudinal microstrip line (96); The first metal ground plane (2) and the second metal ground plane (7) are short-circuited via a plurality of first metal vias (4) and a plurality of second metal vias (6), and the plurality of second metal vias (6) are arranged around the matching network (9); A first clearance area (12) and a second clearance area (13) are respectively provided on the first metal grounding surface (2) and the second metal grounding surface (7), and the antenna booster (3) is arranged in the first clearance area (12); The feeding via (5) is opened at one end of the transverse microstrip line (94), the other end of the transverse microstrip line (94) is connected to one end of the first longitudinal microstrip line (95) through the first matching element (91), the other end of the first longitudinal microstrip line (95) is connected to one end of the second longitudinal microstrip line (96) through the second matching element (92), and the other end of the second longitudinal microstrip line (96) is connected to one end of the antenna enhancer (3); The antenna enhancer (3) is a bent metal strip, the bent end of which is connected to the second longitudinal microstrip line (96); the other end of the antenna enhancer (3) is not in contact with the first metal ground plane (2).

2. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: The first clearance area (12) and the second clearance area (13) have the same size, are respectively opened on the same side of the first metal grounding surface (2) and the second metal grounding surface (7), and are coaxially arranged with the first metal grounding surface (2) and the second metal grounding surface (7).

3. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: In the second metal ground plane (7), an annular groove (8) is provided outside the feeding via (5).

4. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: The first matching element (91) and the second matching element (92) are chip inductors, and the third matching element (93) is a chip capacitor.

5. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: The widths of the transverse microstrip line (94), the first longitudinal microstrip line (95) and the second longitudinal microstrip line (96) are the same.

6. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: The transverse microstrip line (94), the first longitudinal microstrip line (95), and the second longitudinal microstrip line (96) are arranged with equal width gaps on both sides of the first metal ground plane (2).

7. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: The dielectric substrate (1), the first metal ground plane (2), and the second metal ground plane (7) have the same size.

8. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: The plurality of first metal vias (4) are arranged around the edge of the dielectric substrate (1).

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