System ground plane integrated quasi-isotropic antenna based on antenna intensifier

Abstract

The invention discloses a system ground plane integrated quasi-isotropic antenna based on an antenna intensifier, which 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, and is characterized in that the first metal layer is provided with a first metal ground plane, the antenna intensifier and a matching network; the first metal layer is provided with a first metal ground plane, the second metal layer is provided with a second metal ground plane, the first metal ground plane and the second metal ground plane are provided with a first clearance area and a second clearance area respectively, and the first metal ground plane and the second metal ground plane are in short circuit through a first metal via hole and a second metal via hole. According to the quasi-isotropic radiation antenna, the radiation mode of the system ground plane is excited through the antenna intensifier, the equivalent lambda / 4 U-shaped radiator is provided by the system ground plane, quasi-isotropic radiation is realized, and the technical problem that an existing quasi-isotropic antenna cannot keep good radiation performance when the system ground plane exists is solved.

Description

Technical Field

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

[0002] In recent years, the Internet of Things has always been a hot topic. As more and more devices join the Internet of Things network, the randomness of the placement direction and relative position of wireless devices brings new challenges to antenna design. A practical quasi-isotropic antenna that can achieve near-isotropic radiation performance is an ideal choice for such applications. The quasi-isotropic antenna can achieve radiation that covers the entire three-dimensional space without null points.

[0003] Currently, there are mainly the following four methods to achieve quasi-isotropic radiation. The first method is to arrange multiple discrete elements in a circular order, and each element radiates a certain spatial angle, so that the entire array can achieve radiation coverage of the entire space. The second method involves the combination of multiple electric dipoles or monopoles to synthesize a quasi-isotropic radiation pattern. The third method is based on the concept of complementary antennas. By feeding signals with the same amplitude and orthogonal phases to a pair of mutually orthogonal electric dipoles and magnetic dipoles, the null points of the pattern are complemented, and thus quasi-isotropic radiation is achieved. The fourth method is to use a λ / 4 U-shaped radiator structure to achieve quasi-isotropic radiation. However, most of the existing designs ignore a very important factor, that is, the system ground plane existing in wireless devices. When the system ground plane exists, the induced current on the ground plane will damage the radiation characteristics of the antenna. However, in practical applications, the existence of the system ground plane is inevitable.

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

[0005] The purpose of the present invention is to provide a system ground plane integrated quasi-isotropic antenna in view of the deficiencies of the prior art. It can still achieve good quasi-isotropic radiation performance in the presence of the system ground plane, and at the 2.45 GHz frequency point, the present invention achieves a gain variation of 3.66 dB.

[0006] 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 enhancer, comprising 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;

[0008] A first metal ground plane, an antenna enhancer, 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 through-feed via is provided on the dielectric substrate.

[0009] A first clearance area and a second clearance area are respectively formed on the first metal ground plane and the second metal ground plane.

[0010] The first metal ground plane and the second metal ground plane are short-circuited through 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 feed via is formed 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 provided in the first clearance area. The bent end of the antenna enhancer is connected to the second longitudinal microstrip line, and the other end is spaced from the edge of the first clearance area by a distance D.

[0013] In the above technical solution, the first clearance area and the second clearance area have the same size and are respectively formed at the central positions on the corresponding sides of the first metal ground plane and the second metal ground plane.

[0014] In the above technical solution, an annular groove is formed outside the feed via, and the annular groove is formed in the second metal ground plane.

[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 all of them adopt the package size of 0402 specification.

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

[0017] In the above technical solution, the transverse microstrip line, the first longitudinal microstrip line, and the second longitudinal microstrip line have the same width.

[0018] In the above technical solution, the transverse microstrip line, the first longitudinal microstrip line, and the second longitudinal microstrip line are arranged with equal widths of the gaps on both sides of the first metal ground plane.

[0019] In the above technical solution, the material of the dielectric substrate is FR4 material, with a dielectric constant of about 4.4 and a loss tangent of about 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 dimensions.

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

[0022] The working principle of the present invention:

[0023] By the antenna enhancer exciting the radiation mode of the system ground plane, the current distribution on the system ground plane can be equivalent to a λ / 4 U-shaped 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 was traditionally used as a reference plane, into the main radiator. The functional integration of the system ground plane and the radiation element is realized, and the fatal influence of the system ground plane on the quasi-isotropic radiation performance of the antenna in the traditional design can be fundamentally eliminated. 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 working frequency band.

[0024] In summary, in the present invention, the combination of the antenna enhancer, 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 by the present invention still achieves good quasi-isotropic radiation performance in the presence of the system ground plane. By using non-self-resonant elements to replace traditional resonant antenna elements, the limitation of traditional antennas relying on resonant characteristics to achieve radiation is broken through, enabling the antenna to operate in a wider frequency band, improving the applicability and flexibility of the antenna; using the system ground plane as the main radiator realizes the functional integration of the system ground plane and the radiation element, making the antenna structure more compact, smaller in volume, and fundamentally eliminating the adverse influence of the system ground plane on the quasi-isotropic radiation performance in the traditional design.

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

[0028] (3) The antenna proposed by the present invention adopts a planar structure, which is more convenient for integration with wireless devices. Description of the Drawings

[0029] Figure 1 is a three - dimensional structural schematic diagram of the planar integrated quasi - isotropic antenna of the designed system;

[0030] Figure 2 is a two - dimensional structural schematic diagram of the upper surface of the planar integrated quasi - isotropic antenna of the designed system;

[0031] Figure 3 is a two - dimensional structural schematic diagram of the lower surface of the planar integrated quasi - isotropic antenna of the designed system;

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

[0033] Figure 5 is the stack - up information diagram of the planar integrated quasi - isotropic antenna of the designed system;

[0034] Figure 6 is the simulation |S 11 | and gain variation result diagram of the planar integrated quasi - isotropic antenna of the designed system;

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

[0036] Figure 8 is the simulation 2.45GHz two - dimensional normalized gain diagram of the planar integrated quasi - isotropic antenna of the designed system.

[0037] Markings in the figure: 1 - dielectric substrate; 2 - first metal ground plane; 3 - antenna enhancer; 4 - first metal via; 5 - feed via; 6 - second metal via; 7 - second metal ground plane; 8 - annular slot; 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 implementation manners

[0038] In order to better elaborate the technical solutions, design purposes and advantages designed in the present invention, the present invention will be described in detail in combination with embodiments and the accompanying drawings. The specific embodiments used here are only for illustration and do not limit the present invention.

[0039] In the description of the embodiments of the present invention, it should be noted that the terms "first", "second", etc. in the present invention are only for convenience of description and should not be construed as limiting the present invention. In addition, the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings, and is only for convenience of describing the embodiments of the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of the present invention.

[0040] As Figures 1 - 5 shown, a system ground plane integrated quasi-isotropic antenna based on an antenna enhancer, the antenna includes a dielectric substrate 1, a first metal layer 10 provided on the upper surface of the dielectric substrate 1, and a second metal layer 11 provided on the lower surface of the dielectric substrate 1. A first metal ground plane 2, an antenna enhancer 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. A through feed via 5 is provided on the dielectric substrate 1. A first clearance area 12 and a second clearance area 13 are respectively formed on the first metal ground plane 2 and the second metal ground plane 7. The first metal ground plane 2 and the second metal ground plane 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 arranged around the edge of the dielectric substrate 1, and the plurality of second metal vias 6 are arranged 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 enhancer 3 is a bent metal strip and is disposed in the first clearance area 12.

[0042] The other end of the antenna enhancer 3 does not contact the first metal ground plane 2. An annular groove 8 is formed outside the feed via 5.

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

[0044] Further, the first clearance area 12 and the second clearance area 13 have the same size, and are respectively opened at the central positions on the corresponding sides of 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 provided on the first metal layer 10 is L3 = 9.7mm, and the width is W3 = 3.3mm. The gap D between the antenna enhancer 3 and the upper edge of the first clearance area 12 is 0.2mm, and the gap D1 between the antenna enhancer 3 and the lower edge of the first clearance area 12 is 1.1mm. Further, 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] Further, 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 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. The other end of the second longitudinal microstrip line 96 is connected to the bent end of the antenna enhancer 3. Among them, the first matching element 91 and the second matching element 92 are chip inductors, and the third matching element 93 is a chip capacitor, and all adopt the packaging size of 0402 specification. The transverse microstrip line 94 is chamfered. The widths of the transverse microstrip line 94, the first longitudinal microstrip line 95, and the second longitudinal microstrip line 96 are the same, and the width is W5 = 1.5mm. The lengths of the transverse microstrip line 94 and the first longitudinal microstrip line 95 are L7 = 4.5mm and L6 = 2mm respectively. The total length of the second longitudinal microstrip line 96 and the end of the antenna enhancer 3 is L5 = 4.1mm. The transverse microstrip line 94, the first longitudinal microstrip line 95, and the second longitudinal microstrip line 96 are arranged with equal widths of the gaps on both sides with the first metal ground plane 2, and the gaps on both sides are set to 0.5mm.

[0046] Further, the diameters of the first metal via 4 and the second metal via 6 are the same, R1 = 0.4mm. The diameter of the feeding via 5 is R2 = 0.63mm. The diameter of the annular groove 8 opened outside the feeding via 5 is R3 = 1.68mm. The feeding system adopts the coaxial backfeeding method. The feeding via 5 penetrates the substrate to connect the matching network, and the annular groove 8 is arranged around to isolate the inner and outer conductors, ensuring the feeding reliability and avoiding the short circuit of the inner and outer conductors of the coaxial feeder.

[0047] Figure 6 For the simulation of this embodiment |S 11|And the gain variation result graph. It can be seen that through the optimization of the matching network 9, its -10dB impedance bandwidth covers the frequency band from 2.36GHz to 2.54GHz, and the designed center operating frequency point is 2.45GHz. And it can be seen that within the entire -10dB impedance bandwidth, the gain variation is less than -6dB. Specifically, within the entire -10dB impedance bandwidth, a gain variation not greater than 4.5dB is achieved.

[0048] Figure 7 This is the simulation radiation efficiency result graph of this embodiment. It can be seen that good radiation efficiency above 85% is achieved within the entire -10dB impedance bandwidth.

[0049] In order to more intuitively show the realized quasi-isotropic radiation, Figure 8 The simulation two-dimensional normalized gain graph at the 2.45GHz frequency point is given. It can be seen that this embodiment realizes relatively uniform quasi-isotropic radiation at 2.45GHz, and the gain variation at 2.45GHz is 3.66dB. The above data prove that the antenna of the present invention has significant application value in scenarios such as Internet of Things devices, etc., and provides a new technical route for the system planar integrated quasi-isotropic antenna.

[0050] The above is only one embodiment of the present invention, which is only used to help understand the method and core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, the present invention can be improved, and these improvements will also fall within the protection scope of the claims of the present invention. The present invention is not limited to the scope of the specific implementation manner. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions made using the concept of the present invention are within the scope of protection.

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: The first metal layer (10) is provided with a first metal ground plane (2), an antenna enhancer (3) and a matching network (9); the second metal layer (11) is provided with a second metal ground plane (7); and the dielectric substrate (1) is provided with a penetrating feeding via (5); The matching network (9) comprises 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 enhancer (3) is arranged in the first clearance area (12).

2. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 1, characterized in that: 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).

3. The system ground plane integrated quasi-isotropic antenna based on antenna booster according to claim 2, characterized in that: 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).

4. 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).

5. 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).

6. 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.

7. 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.

8. 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).

9. 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.

10. 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).

Images