Dual polarized television receiving antenna for VHF / UHF bands

Abstract

This specification discloses a dual-polarized television receiving antenna suitable for the VHF / UHF bands, primarily addressing the challenge of miniaturization and high performance in existing low-frequency antennas. From bottom to top, it comprises a dielectric substrate, metal stubs, an impedance matching network, a metal radiating element, an X-axis horizontal polarization port, and a Y-axis horizontal polarization port. The metal radiating element employs a multi-segment trapezoidal structure, arranged orthogonally at 90° in space, achieving antenna miniaturization. The metal stubs employ multiple L-shaped structures, symmetrically distributed on the dielectric substrate, and the impedance matching network is distributed on the metal stubs. This invention can cover two operating frequency bands: 150MHz-360MHz and 460MHz-700MHz. It features a compact structure, and simulation verification shows a stable VSWR below 3 in the target frequency band, port isolation less than -25dB, a stable omnidirectional radiation pattern, and excellent diversity performance. It can be used to receive digital television signals in confined indoor environments.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology and relates to a dual-polarized television receiving antenna that can be used in wireless communication systems in the VHF / UHF bands. Background Technology

[0002] Television broadcast signals typically cover two frequency bands: 174-363MHz VHF and 470-698MHz UHF. Currently, similar television antennas operating in both VHF and UHF bands generally suffer from problems such as incomplete frequency coverage, inaccurate impedance matching, significant interference from useless frequency bands, and insufficient stability of the radiation pattern.

[0003] The most similar implementation schemes can be divided into two categories: the first category is a single-band dedicated TV antenna, which is usually only optimized for the UHF band and cannot cover the VHF band at all; the second category is a general broadband TV antenna, which attempts to cover the entire frequency band through broadband design, but lacks a clear structural size and precise matching of lumped parameter matching network, resulting in high energy reflection, low signal transmission efficiency, and easy distortion of radiation direction.

[0004] Patent document CN201310694887.4 discloses a broadband dual-polarized antenna, comprising a feed plate, a dielectric plate, a radiating plate, and a director. The radiating plate has orthogonal ±45° dual-polarized elements, each containing two sub-radiating plates. The feed plate has a two-way sub-feed structure. The dielectric plate is mounted on a reflector via a coaxial cable. The feed plate and radiating plate are printed on the upper and lower layers of the dielectric plate, respectively. The inner conductor of the coaxial cable is connected to the feed plate, feeding one side of the sub-radiating plates through coupling, while the outer conductor connects to the remaining sub-radiating plates. The director is placed above the feed plate. The feed plate and radiating plate respectively regulate high-frequency and low-frequency resonance, and the director optimizes the high-frequency radiation pattern. Because this patented antenna uses orthogonal ±45° slant polarization and includes a director, it radiates energy in a specific direction at high frequencies, making it only suitable as a directional antenna for base stations. It cannot achieve omnidirectional radiation in the horizontal plane, and the antenna size is relatively large at the low frequency of 150MHz, preventing miniaturization at low frequencies.

[0005] Patent application US201916441675 discloses a vertically polarized omnidirectional antenna, which is a coaxially fed vertically polarized omnidirectional antenna. The coaxial cable includes an inner conductor and an outer conductor. The antenna connects a main element, an insulating medium, and a reference ground sequentially from top to bottom. The main element consists of two cross-arranged arms, with the line connecting the intersecting arms passing perpendicularly through the center of the reference ground. The roots of each arm are chamfered. The inner coaxial conductor passes through the reference ground and the insulating medium and connects to the lower end of the main element, while the outer coaxial conductor is connected to the reference ground. This patented antenna can only achieve omnidirectional radiation with single vertical polarization and cannot transmit or receive horizontally polarized electromagnetic waves. Its polarization is limited, and the flat element has a relatively large low-frequency dimension. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of the prior art by providing a television receiving antenna suitable for the VHF / UHF bands. This antenna achieves impedance matching and omnidirectional radiation characteristics in the 150-360MHz and 460MHz-700MHz bands while reducing the physical size of the antenna, thus meeting the design requirements for antenna miniaturization.

[0007] The technical approach to achieving the objective of this invention is as follows: by using a butterfly dipole as the basic radiating unit to cover the VHF / UHF target frequency band, and by folding the original straight-arm metal vibrator, the length of the vibrator is shortened while ensuring that the electrical performance remains unchanged, thereby significantly reducing the overall size of the antenna.

[0008] Based on the above ideas, the technical solution of the present invention is as follows:

[0009] 1. A dual-polarized television receiving antenna suitable for VHF / UHF bands, comprising a dielectric substrate 1, a metallic radiating element 2, a metallic stub 3, an impedance matching network 4, an X-axis horizontal polarization port 5, and a Y-axis horizontal polarization port 6, characterized in that:

[0010] The metal radiating element 2 adopts a multi-segment trapezoidal structure to achieve antenna miniaturization;

[0011] The metal branch 3 adopts multiple sets of L-shaped structures, symmetrically distributed on the dielectric substrate 1, and is used to adjust the impedance matching of the antenna at high frequencies.

[0012] The impedance matching network 4, distributed on the metal stubs 3, is used to adjust the impedance matching of the antenna at low frequencies and suppress unwanted frequency bands.

[0013] Preferably, the multi-group, multi-segment trapezoidal metal radiation array 2 includes four groups, each group having four trapezoidal segments connected in sequence: an inner trapezoid 21, a first transition trapezoid 22, a second transition trapezoid 23, and an outer radiation trapezoid 24. The inner trapezoid 24 and the second transition trapezoid 23 are placed horizontally, and the first transition trapezoid 22 and the outer radiation trapezoid 24 have angles of 50° and 10° with the Z-axis, respectively.

[0014] Preferably, the number of the multiple sets of L-shaped metal branches 3 is the same as the number of trapezoidal metal radiation arrays. Each L-shaped metal branch is connected to the corresponding metal radiation array 2 at both ends through metal support feet and is symmetrically fixed on the upper surface of the dielectric substrate.

[0015] Preferably, the impedance matching network 4 is configured as multiple sets of structures with the same number as the trapezoidal metal radiating elements. Each set includes a resistor 41, an inductor 42, and a capacitor 43. The resistor 41 is distributed at the center of the metal branch 3, and the inductor 42 and capacitor 43 are distributed at both ends of the metal branch 3 and connected in parallel.

[0016] Preferably, the X-direction horizontal polarization port 5 has its port integration line arranged along the X-axis direction, with a height of 21mm-23mm from the dielectric substrate. Circular balun balance welding holes distributed along the X-direction are provided next to the port to realize impedance transformation and balanced power supply of the X-direction horizontal polarization port.

[0017] Preferably, the Y-direction horizontal polarization port 6 has its port integration line arranged along the Y-axis direction, with a height of 31mm-33mm from the dielectric substrate. Circular balun balance welding holes distributed along the Y-direction are provided next to the port to realize impedance transformation and balanced power supply of the Y-direction horizontal polarization port.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] Firstly, this invention significantly reduces the size of the antenna by dividing the traditional flat array into multiple trapezoidal metal array segments and folding and combining them to form a metal radiating array, thus achieving antenna miniaturization and meeting the requirements for installation in narrow indoor environments.

[0020] Secondly, by adding symmetrically arranged L-shaped metal branches on the dielectric substrate and integrating an impedance matching network composed of resistors, inductors, and capacitors, the present invention adjusts the antenna impedance, effectively improving the impedance matching performance in the 150MHz-360MHz and 460MHz-700MHz frequency bands, thus ensuring efficient signal transmission.

[0021] Thirdly, because the present invention employs a structure in which four sets of folded metal vibrators are arranged orthogonally at 90° in space, the antenna radiates omnidirectionally within the operating frequency band, and the radiation pattern is stable without obvious distortion, which can be used to receive omnidirectional television signals. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the antenna of the present invention;

[0023] Figure 2 This is a schematic diagram of the orthogonally placed metal radiating oscillator structure of the antenna of the present invention;

[0024] Figure 3 This is a structural diagram of a single group of four trapezoidal dipoles for the antenna of this invention;

[0025] Figure 4 This is a schematic diagram of the bottom structure of the antenna of the present invention;

[0026] Figure 5 This is a schematic diagram of the L-shaped metal stub of the antenna of the present invention and the distribution of resistors, inductors and capacitors integrated thereon.

[0027] Figure 6 This is a schematic diagram of the dual-port feeding structure at the center of the antenna of the present invention;

[0028] Figure 7 This is a simulated voltage standing wave ratio (VSWR) curve of the antenna of this invention in the 150MHz-700MHz frequency band;

[0029] Figure 8 The antenna S of this invention 12 Simulation curves of parameters in the 150MHz-700MHz frequency band;

[0030] Figure 9 These are simulation curves of the actual gain of the antenna of this invention at different frequencies;

[0031] Figure 10 These are the XOZ plane main polarization and cross polarization patterns of the Y-axis horizontal polarization port of the present invention at different frequency points;

[0032] Figure 11 These are the YOZ plane principal polarization and cross polarization patterns of the Y-direction horizontal polarization port of the present invention at different frequency points;

[0033] Figure 12 These are the XOZ plane principal polarization and cross polarization patterns of the X-direction horizontal polarization port of the present invention at different frequency points;

[0034] Figure 13 These are the YOZ plane principal polarization and cross polarization patterns of the X-direction horizontal polarization port of the present invention at different frequency points;

[0035] Figure 14 This is the diversity performance (ECC) curve of the antenna of this invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

[0037] Reference Figure 1 The dual-polarized television receiving antenna in this example includes a dielectric substrate 1, a metal radiating element 2, a metal stub 3, an impedance matching network 4, an X-axis horizontal polarization port 5, and a Y-axis horizontal polarization port 6. The metal radiating element 2 is arranged orthogonally at 90° above the dielectric substrate 1, as shown below. Figure 2 As shown; there are four groups of metal branches 3, symmetrically distributed on the dielectric substrate 1; the impedance matching network 4 is integrated and distributed on the metal branches 3; the X-axis horizontal polarization port 5 and the Y-axis horizontal polarization port 6 are respectively connected to the two ends of the metal radiation array 2.

[0038] The dielectric substrate 1 is a common support carrier for the antenna. It has a thickness of 0.9mm-1.3mm and a length and width of 115mm-120mm. It is made of FR4 dielectric substrate with a relative permittivity of 4.4 and a loss tangent of 0.02.

[0039] Reference Figure 3 The metal radiating oscillator 2 adopts a multi-segment trapezoidal structure, including four groups. Each group has four trapezoidal segments connected in sequence: an inner trapezoid (21), a first transition trapezoid (22), a second transition trapezoid (23), and an outer radiating trapezoid (24). The inner trapezoid (21) and the second transition trapezoid (23) are placed horizontally, and the first transition trapezoid (22) and the outer radiating trapezoid (24) are distributed above the Z-axis at angles of 50° and 10°, respectively. The inner trapezoid 21 has its upper base connected to the port, and the lengths of its upper and lower bases are 5mm-7mm and 15mm-18mm respectively, with a height of 9mm-11mm; the first transition trapezoid 22 has its upper base connected to the lower base of the inner trapezoid 21, and the lengths of its upper and lower bases are 15mm-18mm and 115mm-120mm respectively, with a height of 75mm-77mm; the second transition trapezoid 23 has its upper base connected to the lower base of the first transition trapezoid 22, and the lengths of its upper and lower bases are 115mm-120mm and 160mm-165mm respectively, with a height of 30mm-33mm; the outer radial trapezoid 24 has its upper base connected to the lower base of the second transition trapezoid 23, and the lengths of its upper and lower bases are 160mm-165mm and 184mm-190mm respectively, with a height of 75mm-79mm.

[0040] Reference Figure 4There are four metal branches 3 in total. Each metal branch is L-shaped and its two ends are connected to the corresponding group of metal radiating elements 2 through metal support feet.

[0041] Reference Figure 5 The impedance matching network 4 is configured as multiple sets of structures with the same number as the trapezoidal metal radiating elements. Each set includes a resistor 41, an inductor 42, and a capacitor 43. The resistor 41 is distributed at the center of the metal branch 3, and the inductor 42 and capacitor 43 are distributed at both ends of the metal branch 3. The inductor and capacitor are connected in parallel and integrated on the metal branch 3.

[0042] Reference Figure 6 The X-axis horizontal polarization port 5 and Y-axis horizontal polarization port 6 of the dual-polarized television receiving antenna are located in the geometric center region of the metal radiating element 2. Specifically: the integration line of the X-axis horizontal polarization port 5 is arranged along the X-axis direction, at a height of 21mm-23mm from the dielectric substrate, and circular balun balance welding holes distributed along the X-axis are provided next to the port for impedance transformation and balanced feeding of the X-axis horizontal polarization port; the integration line of the Y-axis horizontal polarization port 6 is arranged along the Y-axis direction, at a height of 30mm-34mm from the dielectric substrate, and circular balun balance welding holes distributed along the Y-axis are provided next to the port for impedance transformation and balanced feeding of the Y-axis horizontal polarization port.

[0043] The actual parameters and materials of the aforementioned dual-polarized antenna, without changing its structure, can be selected within the range specified according to the specific frequency requirements. Three examples are given below, but are not limited to:

[0044] Example 1: Under the frequency requirements of 150MHz-360MHz and 460-700MHz, the dielectric substrate 1 of this example is made of FR4 material, with a thickness of 1.2mm and a length and width of 115mm; the inner trapezoid 21 has upper and lower bases of 6mm and 16mm respectively, and a height of 10mm; the first transition trapezoid 22 has upper and lower bases of 16mm and 116mm respectively, and a height of 77mm; the second transition trapezoid 23 has upper and lower bases of 116mm and 160mm respectively, and a height of 33mm; the outer main radiating trapezoid 24 has upper and lower bases of 160mm and 184mm respectively, and a height of 79mm; the X-direction horizontal polarization port 5 is 21mm above the dielectric substrate 1, and the Y-direction horizontal polarization port 6 is 32mm above the dielectric substrate 1.

[0045] Example 2: Under the frequency requirements of 100MHz-300MHz and 440MHz-650MHz, the dielectric substrate 1 in this example is made of Megtron M_R5735 board material with a thickness of 1.3mm and a length and width of 120mm; the inner trapezoid 21 has a top and bottom base of 7mm and 18mm respectively, and a height of 10mm; the first transition trapezoid 22 has a top and bottom base of 18mm and 120mm respectively, and a height of 77mm; the second transition trapezoid 23 has a top and bottom base of 120mm and 165mm respectively, and a height of 33mm; the outer main radiating trapezoid 24 has a top and bottom base of 165mm and 190mm respectively, and a height of 79mm; the X-direction horizontal polarization port 5 is 23mm above the dielectric substrate 1, and the Y-direction horizontal polarization port 6 is 34mm above the dielectric substrate 1.

[0046] Example 3: Under the frequency requirements of 200MHz-400MHz and 500-750MHz, the dielectric substrate 1 in this example is made of FR4 board material with a thickness of 1.1mm and a length and width of 110mm; the inner trapezoid 21 has a top and bottom base of 5mm and 15mm respectively, and a height of 9mm; the first transition trapezoid 22 has a top and bottom base of 15mm and 115mm respectively, and a height of 75mm; the second transition trapezoid 23 has a top and bottom base of 115mm and 160mm respectively, and a height of 30mm; the outer main radiating trapezoid 24 has a top and bottom base of 160mm and 185mm respectively, and a height of 75mm; the X-direction horizontal polarization port 5 is 21mm above the dielectric substrate 1, and the Y-direction horizontal polarization port 6 is 30mm above the dielectric substrate 1.

[0047] The technical effects of this invention will be further explained below with reference to simulation experiments:

[0048] 1. Simulation conditions:

[0049] The simulation software is ANSYS Electronics Desktop v21;

[0050] The frequency range of the sweep frequency is 150MHz-700MHz.

[0051] 2. Simulation Content and Results

[0052] Simulation 1: The two-port voltage standing wave ratio (VSWR) of the antenna in Example 1 was simulated within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz. The results are as follows: Figure 7 As shown.

[0053] from Figure 7It can be seen that within the 150-360MHz operating frequency band, the dual-port voltage standing wave ratio (VSWR) remains stable below 3; in the unused frequency band of 360MHz-460MHz, the antenna VSWR increases significantly, reaching a maximum of over 7; within the 460-700MHz operating frequency band, the antenna VSWR continues to decrease and remains stable below 3, achieving good impedance matching in the target operating frequency band while suppressing the unused intermediate frequency band.

[0054] Simulation 2: Within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz, the two-port S-band of the antenna in Example 1 is simulated. 12 The parameters were simulated, and the results are as follows: Figure 8 As shown. From Figure 8 It can be seen that the antenna's S across the entire frequency band 12 All parameters are less than -25dB, with excellent isolation between ports and low coupling interference.

[0055] Simulation 3: The gain of the antenna in Example 1 was simulated within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz. The results are as follows: Figure 9 As shown.

[0056] from Figure 9 It can be seen that within the target operating frequency bands of 150-360MHz and 460-700MHz, the antenna gain increases steadily with frequency. In the middle useless frequency band of 360MHz-460MHz, the antenna gain shows a significant decreasing trend, which is consistent with the suppression trend of voltage standing wave ratio. This effectively reduces noise interference in the middle useless frequency band and improves the signal reception purity of the target frequency band.

[0057] Simulation 4: Within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz, the radiation pattern of the XOZ plane of the Y-direction horizontally polarized port of antenna 1 in this example is simulated at different frequency points. The results are as follows: Figure 10 As shown, where:

[0058] Figure 10 (a) is the XOZ surface radiation pattern at 0.2 GHz;

[0059] Figure 10 (b) is the XOZ surface radiation pattern at 0.28 GHz;

[0060] Figure 10 (c) is the XOZ surface radiation pattern at 0.36 GHz;

[0061] Figure 10 (d) is the XOZ surface radiation pattern at 0.5 GHz;

[0062] Figure 10 (e) is the XOZ surface radiation pattern at 0.6 GHz;

[0063] Figure 10 (f) is the XOZ surface radiation pattern at 0.7 GHz.

[0064] from Figure 10 As can be seen, the main polarization pattern in the XOZ plane exhibits a typical figure-eight distribution within the operating frequency band, with good beam symmetry. Furthermore, the cross-polarization level within the operating frequency band is always much lower than that of the main polarization, demonstrating excellent polarization isolation.

[0065] Simulation 5: The radiation pattern of the Y-axis horizontally polarized port of antenna 1 in this example is simulated at different frequency points within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz. The results are as follows: Figure 11 As shown, where:

[0066] Figure 11 (a) is the radiation pattern of the YOZ plane at 0.2 GHz;

[0067] Figure 11 (b) is the radiation pattern of the YOZ plane at 0.28 GHz;

[0068] Figure 11 (c) is the radiation pattern of the YOZ plane at 0.36 GHz;

[0069] Figure 11 (d) is the radiation pattern of the YOZ plane at 0.5 GHz;

[0070] Figure 11 (e) is the radiation pattern of the YOZ plane at 0.6 GHz;

[0071] Figure 11 (f) is the radiation pattern of the YOZ plane at 0.7 GHz.

[0072] from Figure 11 It can be seen that the main polarization pattern in the YOZ plane maintains an approximately circular quasi-omnidirectional radiation pattern within the operating frequency band, with no obvious radiation null point; and the cross polarization level within the operating frequency band is always much lower than the main polarization, resulting in excellent polarization isolation.

[0073] Simulation 6: Within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz, the radiation pattern of the X-direction horizontally polarized port of the antenna in Example 1 at different frequency points was simulated. The results are as follows: Figure 12 As shown, where:

[0074] Figure 12(a) is the XOZ surface radiation pattern at 0.2 GHz;

[0075] Figure 12 (b) is the XOZ surface radiation pattern at 0.28 GHz;

[0076] Figure 12 (c) is the XOZ surface radiation pattern at 0.36 GHz;

[0077] Figure 12 (d) is the XOZ surface radiation pattern at 0.5 GHz;

[0078] Figure 12 (e) is the XOZ surface radiation pattern at 0.6 GHz;

[0079] Figure 12 (f) is the XOZ surface radiation pattern at 0.7 GHz.

[0080] from Figure 12 As can be seen, the main polarization pattern in the XOZ plane exhibits a typical figure-eight distribution within the operating frequency band, with good beam symmetry; and the cross polarization level within the operating frequency band is always much lower than the main polarization, with excellent polarization isolation.

[0081] Simulation 7: The radiation pattern of the X-direction horizontally polarized port of antenna 1 in this example is simulated at different frequency points within the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz. The results are as follows: Figure 13 As shown, where:

[0082] Figure 13 (a) is the radiation pattern of the YOZ plane at 0.2 GHz;

[0083] Figure 13 (b) is the radiation pattern of the YOZ plane at 0.28 GHz;

[0084] Figure 13 (c) is the radiation pattern of the YOZ plane at 0.36 GHz;

[0085] Figure 13 (d) is the radiation pattern of the YOZ plane at 0.5 GHz;

[0086] Figure 13 (e) is the radiation pattern of the YOZ plane at 0.6 GHz;

[0087] Figure 13 (f) is the radiation pattern of the YOZ plane at 0.7 GHz.

[0088] from Figure 13It can be seen that the main polarization pattern in the YOZ plane maintains an approximately circular quasi-omnidirectional radiation pattern within the operating frequency band, with no obvious radiation null point; and the cross polarization level within the operating frequency band is always much lower than the main polarization, resulting in excellent polarization isolation.

[0089] Simulation 8: The diversity performance (ECC) of the antenna in Example 1 was simulated in the operating frequency bands of 150MHz-360MHz and 460MHz-700MHz. The results are as follows: Figure 14 As shown.

[0090] from Figure 14 As can be seen, the ECC of the antenna remains at an extremely low level within the operating frequency band, meeting the isolation requirements of the MIMO system, with no signal crosstalk issues, and excellent dual-polarization diversity performance.

[0091] The simulation results above show that the dual-polarized TV receiving antenna of the present invention is applicable to the VHF / UHF bands, can work normally in two dual-bands of 150MHz-360MHz and 460-700MHz, and has excellent impedance matching, high dual-polarization isolation, and stable radiation pattern. At the same time, it is small in size, which meets the needs of receiving digital TV signals in narrow indoor environments.

[0092] It should be noted that the above description is merely a specific example of the present invention and does not constitute any limitation on the present invention. Obviously, those skilled in the art, after understanding the content and principles of the present invention, may make various modifications and changes in form and detail without departing from the principles and structure of the present invention. For example, adjusting the material, thickness, and overall size of the dielectric substrate; the size and structure of each trapezoidal segment in the metal radiating array; the structure and parameters of the metal branches; and the component parameters of the impedance matching network; the height of the feed port, etc. In addition to the materials, structures, and parameters selected in this example, different materials, structures, and parameters can be selected according to specific frequency performance requirements. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A dual-polarized television receiving antenna suitable for VHF / UHF bands, comprising a dielectric substrate (1), a metallic radiating element (2), a metallic stub (3), an impedance matching network (4), an X-axis horizontal polarization port (5), and a Y-axis horizontal polarization port (6), characterized in that: The metal radiating element (2) adopts a multi-segment trapezoidal structure to achieve antenna miniaturization; and is arranged orthogonally at 90° in space so that the antenna can radiate omnidirectionally within the operating frequency band; The metal stubs (3) adopt multiple L-shaped structures and are symmetrically distributed on the dielectric substrate (1) to adjust the impedance matching of the antenna at high frequencies. The impedance matching network (4), distributed on the metal stubs (3), is used to adjust the impedance matching of the antenna at low frequencies and suppress unwanted frequency bands.

2. The antenna according to claim 1, characterized in that: The multi-group, multi-segment trapezoidal metal radiation array (2) includes four groups, each group having four trapezoidal segments connected in sequence: an inner trapezoid (21), a first transition trapezoid (22), a second transition trapezoid (23) (9), and an outer radiation trapezoid (24). The inner trapezoid (21) and the second transition trapezoid (23) are placed horizontally, and the first transition trapezoid (22) and the outer radiation trapezoid (24) have angles of 50° and 10° with the Z-axis, respectively.

3. The antenna of claim 1, wherein: The multiple sets of L-shaped metal branches (3) have the same number of trapezoidal metal radiation arrays. Each L-shaped metal branch is connected to the corresponding metal radiation array (2) at both ends through metal support feet and is symmetrically fixed on the upper surface of the dielectric substrate.

4. The antenna of claim 1, wherein: The impedance matching network (4) is configured as a multi-group structure with the same number as the trapezoidal metal radiating elements. Each group includes a resistor (41), an inductor (42), and a capacitor (43). The resistor (41) is located at the center of the metal branch (3), and the inductor (42) and capacitor (43) are located at both ends of the metal branch (3). The inductor and capacitor are connected in parallel.

5. The antenna according to claim 1, characterized in that: The dielectric substrate (1) is a chamfered octagon with a thickness of 0.9mm-1.2mm and a length and width of 110mm-115mm. The material is FR4 dielectric board with a relative permittivity of 4.4 and a loss tangent of 0.

02.

6. The antenna according to claim 1, characterized in that: The X-direction horizontal polarization port (5) has its port integration line set along the X-axis direction, and its height from the dielectric substrate is 21mm-23mm. Circular balun balance welding holes distributed along the X-direction are provided next to the port to realize impedance transformation and balanced power supply of the X-direction horizontal polarization port. The Y-direction horizontal polarization port (6) has its port integral line set along the Y-axis direction, with a height of 31mm-33mm from the dielectric substrate. Circular balun balance welding holes distributed along the Y-direction are provided next to the port to realize impedance transformation and balanced power supply of the Y-direction horizontal polarization port.

7. The antenna of claim 2, wherein: The inner trapezoid (21) has a top bottom connecting port, and the lengths of the top and bottom bottoms are 5mm-6mm and 16mm-17mm respectively, and the height is 10mm-12mm.

8. The antenna according to claim 2, characterized in that: The first transition trapezoid (22) has its upper base connected to the lower base of the inner trapezoid (21), and the lengths of the upper and lower bases are 16mm-17mm and 116mm-117mm respectively, and the height is 77mm-79mm.

9. The antenna according to claim 2, characterized in that: The second transition trapezoid (23) has its upper base connected to the lower base of the first transition trapezoid (22), and the lengths of the upper and lower bases are 116mm-117mm and 160mm-162mm respectively, and the height is 30mm-33mm.

10. The antenna according to claim 2, characterized in that: The outer radial trapezoid (24) has its upper base connected to the lower base of the second transition trapezoid (23), and the lengths of the upper and lower bases are 160mm-162mm and 184mm-186mm respectively, and the height is 75mm-77mm.

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