A low profile compact planar inverted f antenna

Abstract

The application discloses a low-profile miniaturized flat plate vibrator antenna and relates to wireless communication technology. By removing a parasitic unit above a conventional flat plate vibrator antenna, the low-profile problem of the conventional flat plate vibrator antenna is solved; a matching network is loaded at the end of a metal blade, and a coupling block is loaded in the middle, so that broadband design of the antenna is realized; four metal blades are distributed along a central axis at an angle of 90 degrees, one pair of connectors is used as a main radiation structure, and the other pair of connectors is used as a coupling structure, so that the antenna is simple and compact.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication technology, and particularly relates to a low-profile miniaturized planar dipole antenna. Background Technology

[0002] Electronic reconnaissance equipment is an important component of electronic warfare, possessing the capability to detect, analyze, identify, locate, and process intelligence on various types of signals, including radar, communications, and data links. It also features multi-means mission communication, self-defense jamming, battlefield situational awareness, and spectrum surveillance. Among these, interferometer-based reconnaissance and direction-finding systems have become a widely used and effective reconnaissance method due to their advantages such as high positioning accuracy, low computational load, and fast direction-finding speed.

[0003] With the increasing importance and urgency of equipment miniaturization and integration, broadband, miniaturized, and low-profile antenna designs have become current research hotspots. In existing antenna research reports, broadband antennas are generally achieved by loading parasitic elements on top of the flat plate dipole and placing metal blocks on both sides of the dipole. However, loading parasitic elements results in an excessively high overall antenna height, making it difficult to meet the low-profile requirements. Summary of the Invention

[0004] This invention proposes a low-profile miniaturized planar dipole antenna, which solves the problem of low profile that is difficult to achieve in conventional planar dipole antennas by removing the parasitic elements on top of conventional planar dipole antennas.

[0005] The technical solution for achieving this invention is as follows: a low-profile miniaturized planar dipole antenna, comprising a first metal blade, a second metal blade, a third metal blade, a fourth metal blade, a feed connection block, a metal support column, a feed connector, a metal coupling block, a non-metallic support plate, a matching network, and a metal base plate. The first metal blade, the second metal blade, the third metal blade, the fourth metal blade, the four non-metallic support plates, the four metal coupling blocks, and the four matching networks are all distributed in a 90° rotation. The metal coupling blocks, the non-metallic support plates, the matching networks, the first metal blade, and the second metal blade constitute a coupling structure, and the metal coupling blocks, the non-metallic support plates, the matching networks, the third metal blade, and the fourth metal blade constitute a radiating structure. The coupling structure and the radiating structure are orthogonal.

[0006] The four metal blades have identical structures and parameters, consisting of isosceles trapezoidal ends, rectangular bodies, and bent sections. The rectangular body comprises a first cuboid and a second cuboid, with the length and width of the first cuboid being greater than that of the second cuboid. The base of the isosceles trapezoidal end is connected to and equal to that of the first cuboid. The bent section is formed by connecting a third cuboid and a fourth cuboid from top to bottom. The third cuboid is perpendicularly connected to the base of the second cuboid, and the lengths of the connecting sides are equal. The side length of the connecting side of the third cuboid is greater than that of the connecting side of the fourth cuboid. The angle between the two legs of the isosceles trapezoid is 90 degrees, and the isosceles trapezoidal end points to the orthogonal center.

[0007] The third metal blade is connected to the metal support column fixed on the metal base plate by a thread, and the isosceles trapezoidal end of the third metal blade is connected to the power supply connection block.

[0008] The fourth metal blade is connected to the outer conductor of the power supply connector fixed on the metal base plate.

[0009] When the first metal blade, the second metal blade, the third metal blade, and the fourth metal blade are assembled, the bent section faces the metal base plate.

[0010] The lower end of the metal support column is fixed to the metal base plate, and the upper end is connected to the third metal blade and fixed above the metal base plate.

[0011] The upper end of the non-metallic support plate is fixed to the lower end of the metal coupling block, and the lower end of the non-metallic support plate is fixed to the metal boss of the metal base plate.

[0012] The upper end of the metal coupling block is fixed to the metal blade, and the lower end is fixed to the upper end of the non-metallic support plate.

[0013] The upper end of the matching network is fixed to the bottom edge of the fourth cuboid of the metal blade, and the lower end is fixed to the side plate of the metal base plate.

[0014] Compared with the prior art, the significant advantages of this invention are:

[0015] (1) The present invention solves the problem that conventional planar dipole antennas are difficult to achieve low profile by removing the parasitic elements above the conventional planar dipole antenna.

[0016] (2) The present invention uses a matching network loaded at the end of the metal blade and a coupling block loaded in the middle to realize the broadband design of the antenna, with an impedance bandwidth (voltage standing wave ratio less than 3) greater than 66.7%.

[0017] (3) The present invention uses four metal blades that are rotated 90° along the central axis. The antenna structure is compact and the maximum envelope is only 0.157 times the wavelength of the lowest operating frequency. Attached Figure Description

[0018] Figures 1a-1c This is a schematic diagram of a low-profile miniaturized planar dipole antenna according to an embodiment of the present invention, wherein... Figure 1a This is a top view. Figure 1b This is a side view. Figure 1c Main view.

[0019] Figure 2 This is a schematic diagram of the metal blade structure of a low-profile miniaturized planar vibrator antenna.

[0020] Figure 3 This is a schematic diagram of the feed connection block structure for a low-profile miniaturized planar vibrator antenna.

[0021] Figure 4 This is a schematic diagram of the metal coupling block structure of a low-profile miniaturized planar vibrator antenna.

[0022] Figure 5 This is a schematic diagram of a low-profile miniaturized planar vibrator antenna matching network structure.

[0023] Figure 6 This is a schematic diagram of the metal base plate structure of a low-profile miniaturized planar vibrator antenna. Detailed Implementation

[0024] 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 a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0026] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly and specifically defined.

[0027] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; "connection" can mean a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible to those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0029] The following section will further introduce the specific implementation method, as well as the technical difficulties and inventive points of this invention, using this design example as an example.

[0030] Figures 1a-1c This is a schematic diagram of a low-profile miniaturized planar dipole antenna according to an embodiment of the present invention. The low-profile miniaturized planar dipole antenna includes a first metal blade 1, a second metal blade 2, a third metal blade 3, a fourth metal blade 4, a feed connection block 5, a metal support column 6, a feed connector 7, a metal coupling block 8, a non-metallic support plate 9, a matching network 10, and a metal base plate 11. The four metal blades, four non-metallic support plates, four metal coupling blocks, and four matching networks are all distributed at 90° rotations along the central axis. The metal coupling block 8, non-metallic support plate 9, matching network 10, first metal blade 1, and second metal blade 2 form a coupling structure, and the metal coupling block 8, non-metallic support plate 9, matching network 10, third metal blade 3, and fourth metal blade 4 form a radiating structure. The coupling structure and the radiating structure are orthogonal. The four metal blades are fixed above the metal base plate 11 by the metal coupling block 8, non-metallic support plate 9, and matching network 10. The lower end of the metal support column 6 is fixed to the metal base plate 11, and the upper end is fixed to the third metal blade 3. The power supply connector 7 is mounted on the metal base plate 11 via its own flange. Its outer shell passes through the through hole of the metal base plate 11 and is connected to the fourth metal blade 4 by threads. The inner conductor is welded and fixed to the first cuboid of the power supply connection block 5, and the second cuboid of the power supply connection block 5 is fixed to the third metal blade 3.

[0031] The four metal blades have identical structures and parameters, consisting of an isosceles trapezoidal end, a rectangular body, and a bent section. Both the rectangular body and the bent section are composed of two cuboids that decrease in width from wide to narrow. The angle between the two legs of the isosceles trapezoid is 90 degrees, and the isosceles trapezoidal end points towards the orthogonal center. The side of the metal blade facing away from the metal base plate 11 is the front side, and the side facing the metal base plate 11 is the back side.

[0032] like Figure 2The isosceles trapezoidal end (at X01) of the third metal blade 3 is connected to a metal support column 6 fixed on the metal base plate 11 by a thread, and the isosceles trapezoidal end on the front is connected to the second cuboid of the power supply connection block 5; the isosceles trapezoidal end (at X01) of the fourth metal blade 4 is connected to a power supply connector 7 fixed on the metal base plate 11 by a thread; the isosceles trapezoidal ends (at X01) of the first metal blade 1 and the second metal blade 2 are not connected.

[0033] like Figure 3 The second cuboid (at X03) of the power supply connection block 5 is connected to the third metal blade 3, and the second cuboid (at X04) of the power supply connection block 5 is welded to the inner conductor of the power supply connector 7 fixed at the isosceles trapezoidal end of the fourth metal blade 4.

[0034] like Figure 4 As shown, the metal coupling block 8 has two threaded holes at its upper end, which are fixed to the metal blade (at X02); and three threaded holes at its lower end, which are fixed to the upper end of the non-metallic support plate 9.

[0035] like Figure 5 As shown, the matching network 10 is a single-layer PCB board with copper plating at the top and bottom ends of the front side and no copper plating on the back side. It has five metallized vias for grounding and a 500-ohm resistor in the middle. It is fixed to the end of the bent section of the metal blade and the side plate on the metal base plate 11 by fasteners using the outermost vias at the top and bottom ends (at X05).

[0036] like Figure 6 As shown, the metal base plate 11 is integrally formed with four bosses and four side plates. The four bosses are located directly below the metal coupling block 8, and their distance from the antenna center is L9, where L9 = 42 mm. The side plates are located directly below the bent section of the metal blade, and their distance from the antenna center is L10, where L10 = 75.5 mm.

[0037] To ensure miniaturization and low profile, in this embodiment, as shown in Figure 1, the four metal blades are distributed at 90° rotations along the central axis. Their shapes are controlled by optimizing various parameters to determine the form of the antenna radiation pattern. The bent sections of the metal blades, the metal coupling block 8, and the matching network 10 are the core components for achieving antenna miniaturization in this embodiment. The bent sections help increase the electrical length of the antenna, the metal coupling block 8 can enhance the electromagnetic field coupling effect and improve impedance matching, and the matching network 10 is used to adjust impedance matching, achieving the impedance matching characteristics required for antenna miniaturization and low profile design.

[0038] The parameters of the metal blades, metal coupling blocks, and matching network are: d, L1, L2, L3, H1, H2, H3, W1, W2, W3, W04, W05, L6, H6, W6, L7, H7, W7, G1, G2, R. The key characteristic parameters are: d, L1, L2, L3, H2, H3, W1, W2, W3, W04, W05, L6, H6, L7, H7, G1, G2, R. Here, d is the spacing between the first metal blade 1, the second metal blade 2, the third metal blade 3, and the fourth metal blade 4. The lengths of each segment of the L1, L2, L3, H2, and H3 metal blades are used to control the broadband characteristics of the antenna. By adjusting the parameters, the electrical length within a limited space is increased, thereby achieving the broadband characteristics of the antenna.

[0039] W1, W2, W3, W04, and W05 represent the widths of each segment of the metal blade, used to control the antenna impedance characteristics and gain pattern. Wide bandwidth is achieved by adjusting the width. L6, H6, and W6 represent the length, height, and thickness of the metal coupling block. L7, H7, and W7 represent the length, height, and thickness of the matching network. G1 is the distance between the end of the fourth cuboid of the metal blade and the upper plate of the metal base plate. G2 is the distance between the lower end of the metal coupling block and the boss on the metal base plate. R is the resistance value of the matching network.

[0040] Among the control parameters of the metal blades, metal coupling blocks, and matching networks: the spacing d between the first metal blade 1 and the second metal blade 2, the third metal blade 3, and the fourth metal blade 4, d = 11 mm; the parameters L1, L2, L3, H2, and H3 controlling the antenna broadband characteristics are respectively:

[0041] L1=30 mm, L2=35 mm, L3=16mm, H2=35 mm, H3=72 mm.

[0042] W1, W2, W3, W04, and W05 are the widths of each segment of the metal blade, used to control the antenna impedance characteristics and gain pattern. W1 = 6mm, W2 = 26mm, W3 = 35mm, W04 = 35mm, and W05 = 19mm. The thickness of the metal blade is H1, where H1 = 2.5mm. H8 is the height of the side plate, with a distance of G1 = 3.5mm between it and the end of the fourth cuboid of the metal blade. H6 is the height of the metal coupling block, and H9 is the height of the boss, with a distance of G2 = 15.5mm between them. R is the resistance of the matching network, where R = 500Ω. G1, G2, and R need to be matched with the metal blade to achieve antenna impedance matching characteristics and broaden the antenna's bandwidth.

[0043] The first cuboid of the feed connector has a length of L4, L4=18.1mm, a width of W4, W4=4mm, and a thickness of H4, H4=2mm; the second cuboid of the feed connector has a length of L5, L5=6mm, a width of W5, W5=6mm, and a thickness of H5, H5=4mm; the feed connector is used to adjust the impedance matching characteristics of the antenna.

[0044] The metal base plate 11 has a length of L8, L8 = 150 mm, and a width of W8, W8 = 150 mm. Four bosses and four side plates are integrally formed with the metal base plate 11. The four bosses are located directly below the metal coupling block 8, at a distance of L9, L9 = 42 mm from the antenna center. The side plates are located directly below the fourth cuboid of the bent section of the metal blade, at a distance of L10, L10 = 75.5 mm from the antenna center. The metal base plate 11 reflects and superimposes the bidirectional radiated electromagnetic waves, forming directional radiation and improving the antenna gain. The distance between the metal base plate 11 and the metal blade is H, H = 87 mm, which is used to adjust the antenna's operating frequency band and impedance matching characteristics.

Claims

1. A low-profile miniaturized planar dipole antenna, comprising a first metal blade (1), a second metal blade (2), a third metal blade (3), a fourth metal blade (4), a feed connection block (5), a metal support column (6), a feed connector (7), a metal coupling block (8), a non-metallic support plate (9), a matching network (10), and a metal base plate (11), characterized in that: The first metal blade (1), the second metal blade (2), the third metal blade (3), the fourth metal blade (4), four non-metallic support plates (9), four metal coupling blocks (8), and four matching networks (10) are all distributed in a 90° rotation. The metal coupling blocks (8), the non-metallic support plates (9), the matching networks (10), the first metal blade (1), and the second metal blade (2) constitute a coupling structure, and the metal coupling blocks (8), the non-metallic support plates (9), the matching networks (10), the third metal blade (3), and the fourth metal blade (4) constitute a radiating structure. The coupling structure and the radiating structure are orthogonal, wherein: The four metal blades have identical structures and parameters, consisting of isosceles trapezoidal ends, rectangular bodies, and bent sections. The rectangular body comprises a first cuboid and a second cuboid, with the length and width of the first cuboid being greater than that of the second cuboid. The base of the isosceles trapezoidal end is connected to and equal to that of the first cuboid. The bent section is formed by connecting a third cuboid and a fourth cuboid from top to bottom. The third cuboid is perpendicularly connected to the base of the second cuboid, and the connecting sides are of equal length. The side length of the connecting side of the third cuboid is greater than that of the connecting side of the fourth cuboid. The angle between the two legs of the isosceles trapezoid is 90 degrees, and the isosceles trapezoidal end points to the orthogonal center. The third metal blade (3) is connected to the metal support column (6) fixed on the metal base plate (11) by a thread, and the isosceles trapezoidal end of the third metal blade (3) is connected to the power supply connection block (5). The fourth metal blade (4) is connected to the outer conductor of the power supply connector (7) fixed on the metal base plate (11); When the first metal blade (1), the second metal blade (2), the third metal blade (3), and the fourth metal blade (4) are assembled, the bent section faces the metal base plate (11). The lower end of the metal support column (6) is fixed on the metal base plate (11), and the upper end is connected to the third metal blade (3) and fixed above the metal base plate (11); The upper end of the non-metallic support plate (9) is fixed to the lower end of the metal coupling block (8), and the lower end of the non-metallic support plate (9) is fixed to the metal boss of the metal base plate (11); The upper end of the metal coupling block (8) is fixed to the metal blade, and the lower end is fixed to the upper end of the non-metallic support plate (9); The upper end of the matching network (10) is fixed to the bottom edge of the fourth cuboid of the metal blade, and the lower end is fixed to the side plate of the metal base plate (11).

2. The low-profile miniaturized planar dipole antenna according to claim 1, characterized in that: Four metal blades are evenly distributed and rotated 90° around the central axis of the antenna. The four metal blades are isosceles trapezoids facing the axis of rotation. The rectangular bodies of the four metal blades are on the same plane. The distance between the first metal blade (1) and the second metal blade (2) is the same as the distance between the third metal blade (3) and the fourth metal blade (4). The height of the four metal blades from the metal base plate (11) is H, where H = 87 mm. It is used to adjust the working frequency band and impedance matching characteristics of the antenna. It is selected as one-quarter wavelength of the antenna center working frequency. In this embodiment, the height is only 0.167 times the wavelength of the center working frequency, and the profile height is reduced to 66.7% of the normal antenna size.

3. The low-profile miniaturized planar dipole antenna according to claim 2, characterized in that, Among the control parameters of metal blades: The four metal blades have the same structure and parameters; The width W1 of the isosceles trapezoidal end of the metal blade, W1=9mm; The length L1 of the isosceles trapezoidal end of the metal blade, L1 = 30 mm; The width of the first cuboid of the metal blade is W2, W2=69mm, and the length of the first cuboid is L2, L2=35mm; The width of the second cuboid of the metal blade is W3, W3=35mm, and the length of the second cuboid is L3, L3=16mm. The total length of the bent section of the metal blade is H3, H3=72mm. The length of the third cuboid of the bent section is H2, H2=40mm, and the width is 35mm, which is the same as the width of the second cuboid of the rectangular main body. The length of the fourth cuboid of the bent section is H3-H2, which is 32mm, and the width is 19mm. The height of the end of the fourth cuboid from the side plate on the metal base plate (11) is G1, G1=3.5mm. The bent section is used to adjust the impedance matching characteristics and radiation pattern characteristics of the antenna and is an important part of the miniaturization design. The total horizontal extension length of the metal blade is L, where L = L1 + L2 + L3. This length is used to adjust the antenna's operating frequency band and gain characteristics, and is usually chosen to be one-quarter of the lowest frequency of the antenna. In this embodiment, the total length L is greatly shortened by the design of the bending section, resulting in L = 81 mm, which is 0.0945 wavelengths of the lowest frequency of the antenna. The size of the antenna is reduced to 37.8% of the normal antenna size. The thickness of the metal blade is H1, where H1 = 2.5 mm; The spacing between the first metal blade (1) and the second metal blade (2) is d, which is used to control the impedance matching of the antenna. d = 11 mm.

4. The low-profile miniaturized planar dipole antenna according to claim 1, characterized in that, The control parameters of the power supply connection block are: The power supply connection block is composed of a first cuboid and a second cuboid; The first cuboid of the power supply connection block has a length of L4, L4=18.1mm, a width of W4, W4=4mm, and a thickness of H4, H4=2mm; The second cuboid of the power supply connection block has a length of L5, L5=6mm, a width of W5, W5=6mm, and a thickness of H5, H5=4mm.

5. In the low-profile miniaturized planar dipole antenna according to claim 1, the control parameters of the metal coupling block (8) are as follows: The metal coupling block (8) has a length of L6, L6=60mm, a thickness of W6, W6=3mm, and a height of H6, H6=66.5mm. It is used to adjust the working frequency band and impedance matching characteristics of the antenna and is an important part of the miniaturization design. The height of the metal coupling block (8) from the boss on the metal base plate (11) is G2, G2=15.5mm.

6. The low-profile miniaturized planar dipole antenna according to claim 1, characterized in that, Among the control parameters of the matching network (10): The length is L7, L7=19mm, the height is H7, H7=13.5mm, and the thickness is W7, W7=1mm; The matching network (10) is a PCB structure with copper plating at the top and bottom ends and several metallized vias for grounding. Lumped parameter components are connected in the middle, which are any combination of resistors, capacitors and inductors. The matching network (10) is used to adjust the impedance matching characteristics of the antenna and is an important part of the miniaturization design.

7. The low-profile miniaturized planar dipole antenna according to claim 1, characterized in that, Among the control parameters of the metal base plate (11): The length is L8, L8=150mm, and the width is W8, W8=150mm; the four bosses and four side plates are integrally formed with the base plate; the four bosses are located directly below the metal coupling block (8), and their distance from the antenna center is L9, L9=42mm; the side plates are located directly below the bent section of the metal blade, and their distance from the antenna center is L10, L10=75.5mm.

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