Log-periodic dielectric lens broadband high-gain tapered slot antenna

Abstract

The invention discloses a log-periodic dielectric lens broadband high-gain tapered slot line antenna, and relates to the technical field of wireless communication antennae, the log-periodic dielectric lens broadband high-gain tapered slot line antenna comprises a first antenna unit and a second antenna unit which are distributed in parallel and back to back, and the bottoms of the first antenna unit and the second antenna unit are provided with power dividers. A plurality of semi-cylindrical dielectric lenses are arranged between the first antenna unit and the second antenna unit, and the first antenna unit comprises a first metal layer, a dielectric layer and a second metal layer which are arranged from top to bottom. The antenna impedance bandwidth is obviously broadened, the two back antenna units are matched with the symmetrical power division feed network, stable equal-amplitude in-phase excitation is achieved, the radiation efficiency and directivity are improved, radiation beams are focused by embedding the semi-cylindrical dielectric lens on the premise that the system height is not increased, the gain is greatly improved, and side lobes are restrained.

Description

Technical Field

[0001] This invention relates to the field of wireless communication antenna technology, specifically to a log-periodic dielectric lens broadband high-gain tapered slot line antenna. Background Technology

[0002] With the rapid development of technologies such as fifth-generation mobile communication (5G), vehicle-to-everything (V2X), millimeter-wave radar and satellite communication, higher requirements are placed on the performance of antenna systems: they not only need to cover a wider operating bandwidth to support the coexistence of multiple frequency bands or multiple standards, but also need to have high gain, high directivity and compact physical size to adapt to the trend of miniaturization and integration of terminal devices.

[0003] Traditional microstrip patch antennas are widely used due to their simple structure, low cost, and ease of integration. However, their inherent bandwidth is narrow (typically less than 5%), making it difficult to meet the demands of modern broadband communication. To extend bandwidth, existing technologies often employ multi-resonant structures, slot loading, stacked patches, defective ground structures (DGS), or the introduction of parasitic elements. However, these methods often lead to structural complexity, increased fabrication difficulty, or sacrifice of gain or radiation efficiency while increasing bandwidth. On the other hand, to improve antenna gain, array configurations or multi-layer structures are often used, but this results in complex feeding networks, poor phase consistency, and increased size. In recent years, dielectric lenses, due to their passive, low-loss, and focusable electromagnetic wave capabilities, have been used to assist planar antennas in achieving high gain. However, how to efficiently integrate them with broadband antenna elements remains a challenge. Furthermore, if a dual-port antenna needs to be combined into a single-port excitation, it usually relies on an external power divider, which not only increases the system size but may also introduce additional losses and phase errors. Therefore, there is an urgent need for an antenna solution that is compact, easy to manufacture, and has both broadband characteristics and high gain capabilities, which can integrate the antenna elements, feed network and focusing element into a single design to achieve a balance between high performance and high integration. Summary of the Invention

[0004] The purpose of this invention is to provide a log-periodic dielectric lens broadband high-gain tapered slot line antenna.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a log-periodic dielectric lens broadband high-gain tapered slot line antenna, comprising two parallel back-to-back distributed first antenna elements and second antenna elements, wherein the bottom of the first antenna elements and the second antenna elements are provided with power dividers, and multiple semi-cylindrical dielectric lenses are provided between the first antenna elements and the second antenna elements.

[0006] The first antenna element includes a first metal layer, a dielectric layer, and a second metal layer arranged from top to bottom.

[0007] The first metal layer is used to enhance radiation characteristics. The radiation characteristics are achieved by gradient metal grooves. The first metal layer has quarter-circular grooves at its corners and quarter-elliptical arc grooves on its sides. The quarter-circular grooves and quarter-elliptical arc grooves are symmetrically distributed on the surface of the first metal layer. The first metal layer has a combined groove at its center. The combined groove includes a rectangular groove, a circular groove, and a symmetrical exponential groove.

[0008] The second metal layer is used for power supply.

[0009] As a further aspect of the present invention: a copper pillar is embedded in the dielectric layer of the first antenna unit, a metal patch is provided on the second metal layer, a rectangular slot is provided on the bottom side of the dielectric layer of the first antenna unit, a feed line is provided on the second metal layer of the first antenna unit, the feed line is connected to the metal patch of the radiating layer, one section of the feed line is a rectangular straight line, one section is a sloping width gradient line, and the other section is a fan-shaped terminal.

[0010] As a further aspect of the present invention: the power divider includes a first metal layer, a dielectric layer and a second metal layer arranged from top to bottom.

[0011] As a further aspect of the present invention: the first metal layer is a ground layer, the dielectric layer material is the same as the antenna element material, and the second metal layer is used to connect the antenna feed line and provide power division feeding.

[0012] As a further aspect of the present invention: the power divider grounding layer is provided with a metal sheet, the size of which is the same as that of the power divider substrate, for welding the radiating patch of the radiating layer of the first antenna unit and the feeding layer metal patch of the second antenna unit. The metal sheet is provided with a rectangular slit to prevent the feeding wire from being accidentally welded.

[0013] As a further aspect of the present invention: the power divider dielectric layer has a rectangular slot II, which is the same as the slot in the antenna dielectric layer. The first antenna unit and the second antenna unit are embedded therein. The power divider also includes a power divider feed line for connecting the feed lines of the first antenna unit and the second antenna unit. The power divider feed line is composed of multiple left-right symmetrical straight lines and arcs, which converge at the center to form a signal input terminal.

[0014] As a further aspect of the present invention: the dielectric lens is provided in a total of four, and is semi-cylindrical in shape. It is embedded between the first antenna unit and the second antenna unit, with the same length and the radius increasing proportionally from the inside to the outside, in order to enhance the radiation characteristics.

[0015] Compared with the prior art, the beneficial effects of the present invention by adopting the above technical solution are as follows:

[0016] 1. This invention introduces multiple types of composite slot structures on the radiating patch to effectively excite multiple resonant modes, significantly broaden the antenna impedance bandwidth, and achieve stable equal-amplitude and in-phase excitation by two back-facing antenna elements in conjunction with a symmetrical power divider feed network, thereby improving radiation efficiency and directivity.

[0017] 2. This invention focuses the radiation beam without increasing the system height by embedding a semi-cylindrical dielectric lens, thereby significantly improving the gain and suppressing sidelobes.

[0018] 3. This invention adopts a single-layer PCB integrated structure for the entire structure, avoiding the loss and phase error caused by traditional external power dividers. At the same time, it has good mechanical stability and manufacturability. This antenna is particularly suitable for application scenarios with strict requirements for bandwidth, gain and integration, such as 5G millimeter wave communication, vehicle radar, satellite communication and high data rate wireless links.

[0019] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0020] Figure 1 A schematic diagram of a broadband high-gain tapered slot antenna structure;

[0021] Figure 2 This is a schematic diagram of the first metal surface of the antenna element;

[0022] Figure 3 A schematic diagram of the antenna element dielectric layer and the second metal surface;

[0023] Figure 4 A schematic diagram of the first metal surface of the power divider;

[0024] Figure 5 Schematic diagram of the dielectric layer and second metal surface of the power divider;

[0025] Figure 6 This is a schematic diagram of a single medium lens;

[0026] Figure 7 This is a graph showing the antenna voltage standing wave ratio (VSWR).

[0027] Figure 8 This is a comparison chart of antenna gain curves.

[0028] In the diagram: 1. First antenna unit; 2. Second antenna unit; 3. Power divider; 4. Dielectric lens; 101. Radiation patch; 102. Quarter-circular slot; 103. Quarter-elliptical arc slot; 104. Combined slot; 105. Copper pillar; 106. Metal patch; 107. Rectangular slot one; 108. Feeder line; 301. Metal sheet; 302. Rectangular slit; 303. Rectangular slot two; 304. Power divider feeder line. Detailed Implementation

[0029] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be noted that the description of these embodiments is for the purpose of helping to understand the present invention, but does not constitute a limitation of the present invention.

[0030] Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0031] Please see the appendix Figure 1 - Appendix Figure 8 The present invention provides a log-periodic dielectric lens broadband high-gain tapered slot antenna, comprising two parallel back-to-back distributed first antenna element 1 and second antenna element 2, with a power divider 3 at the bottom of the first antenna element 1 and the second antenna element 2, and a plurality of semi-cylindrical dielectric lenses 4 between the first antenna element 1 and the second antenna element 2.

[0032] In embodiment 1, the first antenna unit 1 includes a first metal layer, a dielectric layer, and a second metal layer arranged from top to bottom. The antenna unit adopts a three-layer integrated printed circuit board structure, including a radiating layer (first metal layer), a dielectric layer, and a feed layer (second metal layer). The radiating layer is located on the outermost side, and the feed layer is located on the inner side. The two are isolated and electrically interconnected through the dielectric layer. The first metal layer is used to enhance the radiation characteristics, which are achieved through gradient metal groove lines. A main radiating patch 101 is provided on the radiating layer, and various composite slot structures are etched on the patch. A quarter-circle slot 102 is opened at the corner of the first metal layer, and a quarter-elliptical arc curve slot 103 is opened on the side of the first metal layer. The quarter-circle slot 102 and the quarter-elliptical arc curve slot 103 are connected. The elliptical arc curve slots 103 are symmetrically distributed on the left and right sides of the surface of the first metal layer. A combined slot 104 is opened in the center of the first metal layer. The combined slot 104 includes a rectangular slot, a circular slot, and a symmetrical exponential slot. A quarter-circular slot 102 is denoted by radius r1 and diameter r2. The opening length of the end of the quarter-elliptical arc curve slot 103 is denoted by Wa. The second metal layer is used for feeding and is the feeding layer. The second antenna unit 2 is exactly the same as the first antenna unit 1. The first metal surface, the dielectric layer and the second metal surface are integrated on a PCB substrate, with the first metal surface facing outward and the second metal surface facing inward. The antenna unit substrate has a length denoted by L, a width denoted by W, and a thickness denoted by d.

[0033] Specifically, the dielectric layer of the first antenna unit 1 is a single dielectric substrate with a relative permittivity of 3 and a loss tangent of 0.0018. Copper pillars 105 are embedded in the dielectric layer of the first antenna unit 1, and metal patches 106 are provided on the second metal layer. A rectangular slot 107 is opened on the bottom side of the dielectric layer of the first antenna unit 1. A feed line 108 is provided on the second metal layer of the first antenna unit 1. The feed line 108 is connected to the metal patch 106 of the radiating layer. One section of the feed line 108 is a rectangular straight line, one section is a sloped width gradient line, and the other section is a fan-shaped terminal.

[0034] In this embodiment, the dielectric layer of the first antenna unit 1 is a single low-loss dielectric substrate with a row of metal pillars vertically embedded inside, used to connect the corresponding metal structures in the radiating layer and the feed layer. The rectangular slot 107 on the dielectric layer corresponds in position and size to some slots in the radiating layer to regulate electromagnetic coupling and surface wave propagation. The feed layer of the first antenna unit 1 is composed of a feed line 108, which consists of a straight section, an inclined transmission line with gradually changing width, and a fan-shaped terminal at the end, used to achieve efficient energy transmission and impedance matching from the feed port to the radiating patch. Multiple types of composite slot structures are introduced on the radiating patch 101 to effectively excite multiple resonant modes and significantly broaden the antenna impedance bandwidth. The two back-facing antenna units cooperate with a symmetrical power divider feed network to achieve stable equal-amplitude and in-phase excitation, improving radiation efficiency and directivity.

[0035] In embodiment 2, the power divider 3 includes a first metal layer, a dielectric layer and a second metal layer arranged from top to bottom. The first metal layer is a ground layer, the dielectric layer is made of the same material as the antenna element, and the second metal layer is used to connect the antenna feed line and provide power division feeding.

[0036] Specifically, the power divider 3 has a metal sheet 301 on its ground layer, which is the same size as the power divider 3 substrate. It is used to weld the radiating patch 101 of the radiating layer of the first antenna unit 1 and the second antenna unit 2 to the feed layer metal patch 106. A rectangular slit 302 is opened on the metal sheet 301 to prevent the feed wire 108 from being accidentally soldered. A rectangular slot 303 is opened on the dielectric layer of the power divider 3. The rectangular slot 303 is the same as the slot of the antenna dielectric layer. The first antenna unit 1 and the second antenna unit 2 are embedded therein. The power divider 3 also includes a power divider feed line 304, which is used to connect the feed lines of the first antenna unit 1 and the second antenna unit 2. The power divider feed line 304 is composed of multiple left-right symmetrical straight lines and arcs, which converge at the center to form a signal input terminal. The power divider substrate has a length of Lx and a width of Wx.

[0037] In this embodiment, the power divider 3 also adopts a three-layer structure. Its top layer is a complete grounded metal surface, which is used to support and weld two antenna elements. The grounding layer has a slender gap at the corresponding feed line 108 position to prevent short circuits during welding. The middle dielectric layer has two embedded slots that match the contours of the antenna elements. The bottom layer is a power divider feed network, which is composed of multiple straight lines and arcs arranged symmetrically on the left and right. Finally, they converge at the center to form a single input port, realizing equal amplitude and in-phase excitation of the two antenna elements.

[0038] In Example 3, a total of four dielectric lenses 4 are provided. They are semi-cylindrical in shape and are embedded between the first antenna element 1 and the second antenna element 2. They have the same length and the radius increases proportionally from the inside to the outside to enhance the radiation characteristics.

[0039] Specifically, the dielectric lens 4 has an outward-facing arc surface and an inward-facing plane, and its length is the same as the distance between the two antenna elements. The distance between each lens is the same, and the radius increases proportionally from the inside to the outside. It corrects the wavefront phase through the dielectric focusing effect, enhances the directivity of the main lobe, and improves the peak gain. The length of the dielectric lens 4 is denoted as Lm, and the radii of the semicircular cross-section are denoted as rm1, rm2, rm3, and rm4 from the inside to the outside.

[0040] The preferred dimensions of the broadband tapered slot antenna of the present invention are as follows:

[0041] The length L of the antenna substrate is 133.2 mm.

[0042] The width W of the antenna substrate is 100mm;

[0043] The thickness d of the antenna substrate is 1.6 mm.

[0044] The radius r1 of the quarter-circular groove on the radiating surface is 25 mm.

[0045] The diameter r2 of the circular groove on the radiating surface is 11 mm;

[0046] Wa: 12 mm; Radiant surface symmetry exponential curve groove end opening length Wa: 12 mm;

[0047] The length Lx of the power divider substrate is 128mm;

[0048] The width (Wx) of the power divider substrate is 100mm.

[0049] The length Lm of the dielectric lens is 60mm;

[0050] The cross-sectional radii of the dielectric lens rm1 / rm2 / rm3 / rm4 are 3.75mm / 7.5mm / 15mm / 30mm;

[0051] Furthermore, to better illustrate the technical effects of the antenna provided by the present invention, an antenna was fabricated based on the above-mentioned preferred dimensions, and simulation experiments were conducted. The simulation results were then compared with those of the antenna provided by the present invention. Figure 7-8 The following explanation is provided.

[0052] Figure 7 The VSWR curve reflects the antenna's performance. It can be seen that after optimizing the size, the antenna's VSWR is below 2 in the range of 1.45-6.4GHz, indicating good port impedance matching. Figure 8 The antenna gain comparison curves show that without a lens, the antenna gain is low, and the high-frequency gain drops extremely rapidly, making it difficult to maintain a high gain level in the high-frequency band. Adding a single dielectric lens improves the overall antenna gain across the frequency band, with a peak gain reaching 10dB, although there is still room for improvement. Adding multiple dielectric lenses with proportionally increased radii significantly increases the antenna gain, reaching a peak gain of 12.8dB, and maintaining a high gain of over 10dB at frequencies above 2.5GHz.

[0053] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on.

[0054] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0055] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the described embodiments.

[0056] For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and these variations still fall within the protection scope of the present invention.

Claims

1. A log-periodic dielectric lens broadband high-gain tapered slot line antenna, comprising two parallel back-to-back distributed first antenna elements (1) and second antenna elements (2), characterized in that: The first antenna unit (1) and the second antenna unit (2) are provided with a power divider (3) at the bottom, and a plurality of semi-cylindrical dielectric lenses (4) are provided between the first antenna unit (1) and the second antenna unit (2). The first antenna unit (1) includes a first metal layer, a dielectric layer and a second metal layer disposed from top to bottom; The first metal layer is used to enhance radiation characteristics. The radiation characteristics are achieved by the gradient metal groove lines. The first metal layer has a quarter-circle groove (102) at its corner and a quarter-elliptical arc groove (103) on its side. The quarter-circle groove (102) and the quarter-elliptical arc groove (103) are symmetrically distributed on the surface of the first metal layer. The first metal layer has a combined groove (104) at its metal center. The combined groove (104) includes a rectangular groove, a circular groove and a symmetrical exponential groove. The second metal layer is used for power supply.

2. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 1, characterized in that: The first antenna unit (1) has a copper pillar (105) embedded in the dielectric layer, and a metal patch (106) is provided on the second metal layer. A rectangular slot (107) is opened on the bottom side of the dielectric layer of the first antenna unit (1). A feed line (108) is provided on the second metal layer of the first antenna unit (1). The feed line (108) is connected to the metal patch (106) of the radiating layer. One section of the feed line (108) is a rectangular straight line, one section is a sloping width gradient line, and the other section is a fan-shaped terminal.

3. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 1, characterized in that: The second antenna element (2) is exactly the same as the first antenna element (1).

4. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 1, characterized in that: The power divider (3) includes a first metal layer, a dielectric layer and a second metal layer arranged from top to bottom.

5. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 4, characterized in that: The first metal layer is a ground layer, the dielectric layer material is the same as the antenna element material, and the second metal layer is used to connect the antenna feed line and provide power divider feeding.

6. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 1, characterized in that: The power divider (3) has a metal sheet (301) on its ground layer, which is the same size as the power divider (3) substrate. It is used to weld the radiating patch (101) of the first antenna unit (1) and the feeding layer metal patch (106) of the second antenna unit (2). A rectangular slit (302) is opened on the metal sheet (301) to prevent the feed line (108) from being accidentally welded.

7. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 1, characterized in that: The power divider (3) has a rectangular slot 2 (303) in its dielectric layer. The rectangular slot 2 (303) is the same as the slot in the antenna dielectric layer. The first antenna unit (1) and the second antenna unit (2) are embedded therein. The power divider (3) also includes a power divider feed line (304) for connecting the feed lines of the first antenna unit (1) and the second antenna unit (2). The power divider feed line (304) is composed of multiple left-right symmetrical straight lines and arcs, which converge at the center to form a signal input terminal.

8. The log-periodic dielectric lens broadband high-gain tapered slot line antenna according to claim 1, characterized in that: There are four dielectric lenses (4) in total. They are semi-cylindrical in shape and are embedded between the first antenna unit (1) and the second antenna unit (2). They have the same length and the radius increases proportionally from the inside to the outside to enhance the radiation characteristics.

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