Broadband dual-polarization magnetoelectric dipole antenna with polygonal horizontal patch

Abstract

The invention discloses a broadband dual-polarization magnetoelectric dipole antenna with a polygonal horizontal patch. The broadband dual-polarization magnetoelectric dipole antenna comprises an electric dipole, a magnetic dipole, a feed structure and a box-type reflector. The electric dipole is composed of four polygonal horizontal patches with the same size, and a metal semicircular ring is fixed at a rectangular groove of every two adjacent polygonal patches. The magnetic dipole is composed of four groups of vertically arranged metal plates and located below the electric dipole, the feed structure is composed of a cross-shaped horizontal plate and four vertical metal plates, and rectangular grooves are etched in the two sides and the lower edge of each metal plate. The relative bandwidth reaches 104.8%, the isolation degree is superior to 48dB, a plurality of communication frequency bands can be covered while the structure is simple, the good radiation characteristic is achieved, and the requirement for modern communication multi-frequency-band transmission can be better met.

Description

Technical Field

[0001] The present invention belongs to the field of communication technology, and further relates to a broadband dual-polarized magnetoelectric dipole antenna with a polygonal horizontal patch in the field of antenna technology. The present invention can achieve mutual compatibility between different communication systems by expanding the antenna bandwidth in antenna design to meet the needs of different communication systems. Background Art

[0002] With the continuous growth of the number of communication users, modern communication systems have also put forward higher requirements for channel capacity and spectrum utilization efficiency. Traditional microstrip antennas are difficult to meet the needs of modern communication systems due to their narrow bandwidth, and the demand for high-performance broadband antennas is becoming more and more urgent. As a typical broadband antenna, magnetoelectric dipole antennas have attracted widespread attention due to their good radiation characteristics such as wide bandwidth, high gain and stable radiation pattern. In order to more effectively utilize the spectrum resources of communication systems, dual-polarization antennas have been widely used to resist multipath fading and improve channel capacity. In the existing dual-polarization antenna design, the broadband design of the antenna is usually achieved by slotting the radiating patch, loading impedance elements or parasitic elements, and changing the feeding structure. The radiating patch slot is used to change the equivalent length and resonance mode of the antenna, so that the antenna introduces additional resonance modes to expand the bandwidth. However, the shape and size of the slot structure should be fully considered when slotting. Different slot structures will have different effects on the antenna performance. By loading impedance elements, the surface current of the antenna is distributed in a traveling wave, thereby obtaining broadband characteristics. By loading parasitic elements, the parasitic elements are coupled with the radiating patch to generate multi-resonance characteristics to expand the bandwidth. However, while achieving broadbandization through resistance loading, the antenna loss will increase, and the capacitance and inductance loading is difficult to achieve. In addition, the introduction of parasitic elements will increase the size of the antenna and increase the complexity of the structure. Although the bandwidth can be expanded through the above method, there are still some limitations in the actual design process of widening the bandwidth. First, the bandwidth coverage of some antennas is limited, and the communication frequency bands that can be covered are relatively small. In addition, the impedance matching of some frequency bands of some antennas is not ideal when the bandwidth is expanded, which makes it difficult to meet the requirements of modern communication systems for multi-band transmission. Secondly, while expanding the antenna bandwidth, it is often accompanied by a more complex antenna structure, which not only increases the complexity of the design, but also increases the manufacturing cost of the antenna. In addition, the complex antenna structure also poses challenges to achieving good impedance matching and radiation performance within a wide bandwidth.

[0003] Yuhui Ren, Ke Li, Xudong Li, Xteyu Jin and others proposed a disk-loaded broadband dual-polarized magneto-electric dipole antenna in their published paper "A wideband dual-polarized magneto-electric dipole antenna loaded with a disk" (International Journal of RF and Microwave Computer-Aided Engineering, 2021). The antenna consists of a pair of orthogonally placed magneto-electric dipoles, a pair of orthogonal Г-shaped feeders, a disk resonator and a metal cylindrical reflector. The antenna is excited by two similar Г-shaped coaxial feeders to achieve dual polarization, and the impedance characteristics of the antenna are changed by loading a disk resonator at the front end of the dipole, thereby extending the antenna bandwidth. However, the antenna still has the disadvantage that although the operating frequency range of the antenna is extended to 1.2GHz-2.4GHz by loading the disk resonator, the relative bandwidth of the antenna is 68%, but this bandwidth is still not enough to cover a wider range of communication frequency bands, such as the main frequency band of Sub-6GHz in 5G communication, and the introduced disk resonator increases the size of the antenna and makes the antenna structure complicated, increasing the difficulty of design and manufacturing.

[0004] Cam Ha Le Thi, Son Xuat Ta, Xuan Quyen Nguyen and others proposed a broadband dual-polarized magnetoelectric dipole antenna for 5G applications in their paper "Design of compact broadband dual-polarized antenna for 5G applications" (International Journal of RF and Microwave Computer-Aided Engineering, 2021). The antenna consists of four short-circuit patches and a microstrip line aperture coupling feeding structure. Two orthogonal microstrip lines achieve broadband dual-polarized radiation through cross-shaped gaps on the ground plane, and the bandwidth is expanded by using the microstrip line aperture coupling feeding structure. However, the operating frequency range of the antenna is 3.02GHz-4.02GHz, and the relative bandwidth can only reach 33%. The operating frequency band can only cover the n78 frequency band of 5G NR, and this structure will cause a large amount of back radiation, making the antenna radiation performance poor, and it needs to be loaded with a high impedance surface to suppress it, which will further increase the complexity and cost of the structure.

[0005] Tianjin Vocational and Technical Normal University (China Vocational Training Instructor Continuing Education Center) proposed a broadband dual-polarized magneto-electric dipole antenna in its patent application document "A broadband dual-polarized magneto-electric dipole antenna" (patent application number: 202420403359.2, application publication number: CN222052078 U). The antenna consists of a magnetic dipole, an electric dipole, a feed substrate and an orthogonal probe structure. The four groups of magnetic dipole pairs are rotationally symmetrical and evenly placed along the vertical central axis. The electric dipole is horizontally placed above the four groups of magnetic dipoles. The feed substrate is a dielectric substrate, and the upper and lower layers are coated with metal layers. The magnetic dipole is fixed on the metal layer. The antenna realizes dual polarization by using two mutually orthogonal Г-shaped feed lines. By opening mutually perpendicular rectangular slots on each electric dipole, the current loop is increased, thereby expanding the antenna bandwidth. However, the antenna still has some shortcomings. The impedance matching performance of the antenna is poor in some frequency bands, which makes the antenna perform poorly in some frequency bands. At the same time, since the operating frequency range of the antenna is 0.93GHz-2.02GHz and the relative bandwidth reaches 72.6%, the communication frequency band coverage of the antenna is still relatively limited. It is only suitable for low frequency bands and it is difficult to meet the communication needs of high frequency bands. Summary of the invention

[0006] The purpose of the present invention is to address the deficiencies in the above-mentioned prior art and propose a broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch, aiming to solve the problems in the prior art of limited working bandwidth of dual-polarized antennas, unsatisfactory impedance matching of some frequency bands of broadband antennas that cannot meet the multi-band transmission requirements of modern communications, and increased complexity of the antenna structure when expanding the bandwidth.

[0007] The idea of ​​achieving the purpose of the present invention is: by using four polygonal horizontal patches of the same size to form an electric dipole, specifically, two rectangular grooves are etched at two diagonal positions of each traditional square electric dipole patch, and at the same time, an isosceles triangle corner is cut off at the vertex position away from the center of the antenna. This change in shape allows the current to flow along a more complex path on the surface of the horizontal patch, thereby changing the current distribution on the horizontal patch, so that the antenna generates a new resonance point at 4GHz, and the antenna bandwidth is expanded. By fixing a metal semicircular ring with a notch at the rectangular groove of two adjacent polygonal horizontal patches, the electric field and magnetic field characteristics of the antenna are effectively changed, so that the current of the antenna is mainly concentrated on these metal rings at 4.7GHz, thereby generating a new resonance point at 4.7GHz, and the increase in the resonance point effectively expands the working frequency range of the antenna. In addition, by improving the feeding structure, specifically etching symmetrical grooves on both sides and the lower edge of the vertical metal plate of the cross-shaped feeding structure, the input impedance of the antenna can be adjusted, so that the antenna matches the transmission line impedance at different frequencies, thereby effectively improving the antenna impedance matching and further expanding the antenna bandwidth. Through the above improvements, the resonance characteristics and impedance matching of the antenna are changed, and the antenna generates new resonance points at 4GHz and 4.7GHz, which effectively expands the bandwidth of the antenna. The operating frequency range of the antenna is 1.53GHz-4.90GHz, and the relative bandwidth reaches 104.8%, which can cover multiple communication frequency bands. The present invention has a simple structure and achieves a significant expansion of the antenna bandwidth.

[0008] The broadband dual-polarized magneto-electric dipole antenna of the present invention comprises an electric dipole, a magnetic dipole, a feeding structure and a box-shaped reflector; the electric dipole is composed of four polygonal horizontal patches of the same size and arranged rotationally symmetrically along the center of the antenna; metal semicircular rings are fixed at the rectangular grooves of two adjacent polygonal patches, and the four metal semicircular rings are symmetrically distributed along the center of the antenna.

[0009] Furthermore, each polygonal horizontal patch includes two rectangular grooves of the same shape and size and a cut corner, each rectangular groove is located at a diagonal position of the horizontal patch, and the depth of the rectangular groove is equal to the thickness of the horizontal patch; an isosceles right triangle is cut off the vertex angle of each horizontal patch away from the center of the antenna, and the length of the two right-angled sides of the cut corner of the triangle is less than or equal to half the length of the side of the horizontal patch, and its thickness is equal to the thickness of the horizontal patch.

[0010] Furthermore, a rectangular notch is opened in the middle of each metal semicircular ring, and the thickness of each metal semicircular ring is equal to the thickness of the horizontal patch.

[0011] Furthermore, the magnetic dipole is composed of four groups of vertically arranged metal plates, each group of metal plates includes two rectangular metal plates with equal heights and perpendicular to each other, which are arranged rotationally symmetrically along the center of the antenna below the four electric dipoles.

[0012] Furthermore, the feeding structure is placed in the middle of four polygonal horizontal patches and consists of a cross-shaped horizontal plate and four vertical metal plates.

[0013] Furthermore, rectangular grooves are etched on both sides and the lower edge of each vertical metal plate of the feeding structure, and the depth of the rectangular grooves is equal to the thickness of the feed line; wherein the rectangular grooves on both sides have the same shape and size and are symmetrically distributed along the center of the antenna; the rectangular grooves on the lower edge have the same shape and size and are symmetrically distributed along the center of the antenna, the grooves on both sides are different in size from the grooves on the lower edge, the length of the grooves on both sides is significantly longer than the length of the grooves on the lower edge, and the width of the grooves on both sides is slightly narrower than the width of the grooves on the lower edge.

[0014] Furthermore, the feeding structure has four feeding ports, Port 1 at both ends of the lower edge of each pair of vertical metal plates. + and Port1 - A pair of differential ports 1 and a pair of Port2 at the bottom of the vertical metal plate + and Port2 - A pair of differential ports 2 is formed, and each pair of differential ports is fed with differential signals with equal amplitudes and 180° phase difference, respectively. The differential signals excite the antenna through the SMA header under the floor.

[0015] Furthermore, the box-type reflector is a square box with an open top, which is used to reduce back radiation.

[0016] Furthermore, the magnetic dipole, the electric dipole, the four metal semicircular rings and the feeding structure are all placed in the box-type reflector.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] First, since the electric dipole of the present invention is composed of four polygonal horizontal patches of the same size and rotationally symmetrically arranged along the center of the antenna, it overcomes the problem of increasing the complexity of the antenna structure when expanding the bandwidth in the prior art, so that the present invention achieves effective expansion of the bandwidth while having a simple structure.

[0019] Secondly, the present invention effectively changes the electric field and magnetic field characteristics of the antenna by fixing the metal semicircular rings at the rectangular grooves of two adjacent polygonal patches of the electric dipole, thereby overcoming the problem of limited antenna bandwidth extension in the prior art. The current of the antenna of the present invention is mainly concentrated on these metal rings at 4.7 GHz, thereby generating a new resonance point at 4.7 GHz. The increase in the resonance point effectively expands the operating frequency range of the antenna and further expands the bandwidth of the antenna.

[0020] Third, because the present invention improves the feeding structure and etches rectangular grooves on both sides and the lower edge of each vertical metal plate of the feeding structure, it overcomes the problem of unsatisfactory impedance matching in some frequency bands when the broadband antenna expands the bandwidth in the prior art, so that the present invention has good impedance matching in the entire working frequency band, can cover multiple communication frequency bands, and better meet the needs of multi-band transmission in modern communications. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0022] Figure 2 is a schematic diagram of the feeding structure of the present invention;

[0023] Figure 3 is a schematic diagram of the structure of an embodiment of the present invention, wherein: Figure 3 (a) is a schematic diagram of the top view of the structure. Figure 3 (b) is a schematic diagram of the side structure;

[0024] Figure 4 This is the result diagram of the simulation experiment 1 of the present invention, where: Figure 4 (a) is the current distribution diagram at 1.6 GHz. Figure 4 (b) is the current distribution diagram at 2.2 GHz. Figure 4 (c) is the current distribution diagram at 4 GHz. Figure 4 (d) is the current distribution diagram at 4.7 GHz;

[0025] Figure 5 It is a simulation curve diagram of the differential mode reflection coefficient of the simulation experiment 2 of the present invention at 1GHz-5.3GHz;

[0026] Figure 6 This is a simulation curve diagram of the isolation degree of the simulation experiment 3 of the present invention at 1 GHz-5.3 GHz;

[0027] Figure 7 It is a gain simulation curve diagram of the differential port 1 at 1 GHz-5.3 GHz in the simulation experiment 4 of the present invention;

[0028] Figure 8 This is the simulated radiation pattern of the simulation experiment 5 of the present invention at four frequency points, where: Figure 8 (a) is the radiation pattern at 1.6 GHz, Figure 8 (b) is the radiation pattern at 3 GHz. Figure 8 (c) is the radiation pattern at 4 GHz, Figure 8 (d) is the radiation pattern at 4.7 GHz.

[0029] Explanation of the reference numerals: 1 is a polygonal horizontal patch, 1-1 and 1-2 are rectangular grooves, 1-3 is an isosceles right triangle, 2 is a vertically arranged metal plate, 3 is a feeding structure, 4 is a metal semicircular ring, 5 is a box-type reflector, 3-1 and 3-2 are rectangular grooves on both sides, 3-3 and 3-4 are rectangular grooves on the lower edge, W is the length of the polygonal horizontal patch 1, S is the gap between the polygonal horizontal patches 1, L is the length of the polygonal horizontal patch 1, 1 is the length of the two diagonally located rectangular slots 1-1 and 1-2, L 2 is the width of the rectangular grooves 1-1 and 1-2 at the two diagonal positions of the polygonal horizontal patch, L 3 is the length of the right angle side of the cut isosceles right triangle 1-3, c is the width of the metal semicircular ring 4, R w is the length of the gap in the middle of the metal semicircular ring, m is the length of the cross-shaped horizontal plate in the feed structure 3, d is the width of the cross-shaped horizontal plate in the feed structure 3, g is the length of each rectangular metal plate, H is the height of each rectangular metal plate, h 1 is the height of each vertical metal plate in the feeding structure 3, V h The lengths of the two rectangular grooves 3-1 and 3-2 on both sides of each vertical metal plate, V w The width of the two rectangular grooves 3-1 and 3-2 on both sides of each vertical metal plate, V m The length of the two rectangular grooves 3-3 and 3-4 at the lower edge of each vertical metal plate is V n is the width of the two rectangular grooves 3-3 and 3-4 at the lower edge of each vertical metal plate, G is the length of the box-type reflector 5, P is the height of the box-type reflector 5, and t is the thickness. DETAILED DESCRIPTION

[0030] The embodiments and effects of the present invention are further described below in conjunction with the accompanying drawings.

[0031] Reference Figure 1 , the overall structure of the present invention is further described.

[0032] The broadband dual-polarization magneto-electric dipole antenna with a polygonal horizontal patch of the present invention comprises an electric dipole, a magnetic dipole, a feeding structure 3, a metal semicircular ring 4 and a box-shaped reflector 5.

[0033] The electric dipole is composed of four polygonal horizontal patches 1 of the same size and arranged rotationally symmetrically along the center of the antenna. The polygonal horizontal patch 1 includes two rectangular grooves 1-1, 1-2 of the same shape and size and a cut corner. The rectangular grooves 1-1, 1-2 are respectively located at the diagonal positions of the horizontal patches, and the depth of the rectangular grooves is equal to the thickness of the horizontal patches. An isosceles right triangle 1-3 is cut off from the vertex of each horizontal patch away from the center of the antenna, and its thickness is equal to the thickness of the horizontal patch. The electric dipole of the present invention uses four polygonal horizontal patches of the same size, which changes the current distribution on the horizontal patches, thereby introducing additional resonant modes, so that the antenna generates a new resonance point at 4GHz.

[0034] A metal semicircular ring 4 is fixed at the rectangular groove of two adjacent polygonal patches. The four metal semicircular rings are symmetrically distributed along the center of the antenna. A rectangular notch is opened in the middle of each metal semicircular ring, and the thickness of each metal semicircular ring is equal to the thickness of the horizontal patch. By fixing the four metal semicircular rings, the electric field and magnetic field characteristics are changed, so that the antenna generates a new resonance point at 4.7GHz.

[0035] The magnetic dipole is composed of four groups of vertically arranged metal plates 2, each group of metal plates includes two rectangular metal plates of equal height and perpendicular to each other, which are arranged rotationally symmetrically along the center of the antenna below the four electric dipoles.

[0036] Reference Figure 2 , the feeding structure 3 of the present invention is further described.

[0037] The feeding structure 3 is placed in the middle of the four electric dipoles, and is composed of a cross-shaped horizontal plate and four vertical metal plates. Both sides and the lower edge of each vertical metal plate are provided with rectangular grooves, and the depth of the rectangular grooves is equal to the thickness of the feed line. Among them, the rectangular grooves 3-1 and 3-2 on both sides are consistent in shape and size and are symmetrically distributed along the center of the antenna, and the rectangular grooves 3-3 and 3-4 on the lower edge are consistent in shape and size and are symmetrically distributed along the center of the antenna. The impedance matching of the antenna is improved by improving the feeding structure, so that the antenna maintains good impedance matching in the entire operating frequency range.

[0038] Reference Figure 3 (a) is a further description of the top view structure of an embodiment of the present invention.

[0039] The length of the polygonal horizontal patch 1 is W=30 mm, and the gap between the four polygonal horizontal patches 1 is S=11 mm. The length of the rectangular grooves 1-1 and 1-2 at the two diagonal positions of each polygonal horizontal patch 1 is L 1 =7mm, width is L 2 =6.8mm, the length of the right angle side of the isosceles right triangle 1-3 cut off from each polygonal horizontal patch 1 is L3 =11mm.

[0040] The width of the metal semicircular ring 4 fixed at the rectangular groove of two adjacent polygonal patches is c=2mm, and the length of the gap in the middle of the metal semicircular ring is R w =6.5mm.

[0041] The length of the cross-shaped horizontal plate in the feeding structure 3 is m=30.8 mm, the width is d=9 mm, and the Port 1 at both ends of the lower edge of each pair of vertical metal plates in the feeding structure 3 is + and Port1 - A pair of differential ports 1 and a pair of Port2 at the bottom of the vertical metal plate + and Port2 - A pair of differential ports 2 is formed, and each pair of differential ports is fed with differential signals with equal amplitudes and 180° phase difference. The differential signals excite the antenna through a pair of SMA heads under the floor. The differential feeding technology is used to improve the port isolation of the antenna.

[0042] Reference Figure 3 (b) further describes the side view structure of the embodiment of the present invention.

[0043] The magnetic dipole, electric dipole, four metal semicircular rings and feeding structure are placed in a box-type reflector 5 with a length of G=145mm and a height of P=27mm to reduce back radiation. The box-type reflector changes the radiation pattern of the antenna by reflecting and absorbing back electromagnetic waves, thereby reducing back radiation.

[0044] In the four groups of vertically arranged metal plates 2 constituting the magnetic dipoles, each group of metal plates 2 includes two mutually perpendicular rectangular metal plates, and each rectangular metal plate has a height of H=31 mm and a length of g=23 mm.

[0045] The height of the four vertical metal plates in the feeding structure 3 is h 1 = 24.5 mm, the length of the rectangular grooves 3-1 and 3-2 on both sides of each vertical metal plate is V h =6.5mm, width V w =1.3mm, the length of the rectangular grooves 3-3 and 3-4 at the lower edge of each vertical metal plate is V m =2.2mm, width V n =1.8mm.

[0046] The thickness of the electric dipole, magnetic dipole, feeding structure 3, metal semicircular ring 4 and box-shaped reflector 5 is t=1 mm.

[0047] The technical effects of the present invention are further illustrated below in conjunction with simulation experiments.

[0048] 1. Simulation conditions and contents.

[0049] Simulation 1, using the simulation experiment software platform Ansoft HFSS electromagnetic simulation software, at 1.6GHz, 2.2GHz, 4GHz, 4.7GHz, the current distribution diagram of the differential port 1 of the present invention is simulated. The simulation results are as follows: Figure 4 (a), Figure 4 (b) Figure 4 (c) Figure 4 (d) as shown.

[0050] Simulation 2, using the simulation experiment software platform Ansoft HFSS electromagnetic simulation software, in the range of 1GHz-5.3GHz, the differential mode reflection coefficient of the present invention is simulated, and the results are plotted as follows Figure 5 The curve shown.

[0051] Simulation 3, using the simulation experiment software platform Ansoft HFSS electromagnetic simulation software, in the range of 1GHz-5.3GHz, the isolation of the present invention is simulated, and the results are plotted as follows: Figure 6 The curve shown.

[0052] Simulation 4, using the simulation experiment software platform Ansoft HFSS electromagnetic simulation software, the gain of the differential port 1 of the present invention is simulated in the range of 1GHz-5.3GHz, and the plotting results are as follows: Figure 7 The curve shown.

[0053] Simulation 5, using the simulation experiment software platform Ansoft HFSS electromagnetic simulation software, at 1.6GHz, 3GHz, 4GHz, 4.7GHz four frequency points, the radiation pattern of the present invention is simulated respectively, and the results are plotted as shown in Figure 8 (a), Figure 8 (b) Figure 8 (c) Figure 8 (d) shows the curve.

[0054] 2. Analysis of simulation results.

[0055] The effects of the present invention are further described below in conjunction with the simulation result diagram of the embodiment.

[0056] Figure 4 It is a simulation diagram of current distribution obtained at four frequency points when the antenna in the simulation experiment 1 of the present invention is excited at the differential port 1. Figure 4 The color of the icon on the left represents the intensity of the current. Blue represents a smaller current intensity, and red represents a larger current intensity. Figure 4 (a) is the current distribution diagram at 1.6 GHz. Figure 4 (b) is the current distribution diagram at 2.2 GHz. Figure 4 (c) is the current distribution diagram at 4 GHz. Figure 4 (d) is the current distribution diagram at 4.7 GHz.

[0057] from Figure 4 It can be seen from (a) that the current intensity on the electric dipole of the antenna of the present invention is relatively large at 1.6 GHz, indicating that the electric dipole plays a leading role at 1.6 GHz. Figure 4 It can be seen from (b) that the current intensity on the magnetic dipole of the antenna of the present invention is relatively large at 2.2 GHz, indicating that the magnetic dipole plays a leading role at 2.2 GHz. Figure 4 It can be seen from (c) that at 4 GHz, the current intensity around the rectangular groove etched on the polygonal horizontal patch of the antenna of the present invention is relatively large, indicating that at 4 GHz, the rectangular groove etched on the polygonal horizontal patch plays a dominant role. Figure 4 As can be seen from (d) in the figure, when the antenna of the present invention is at 4.7 GHz, the current intensity on the metal semicircular ring is relatively large, indicating that at 4.7 GHz, the metal semicircular ring plays a leading role.

[0058] Figure 5 It is a simulation curve diagram of the differential mode reflection coefficient of the antenna at 1 GHz-5.3 GHz in the simulation experiment 2 of the present invention. Figure 5 The horizontal axis represents the frequency in GHz, and the vertical axis represents the differential mode reflection coefficient (|S dd |), the unit is dB. Among them, the curve marked by the red solid line |S dd11 | represents the relationship between the differential mode reflection coefficient and frequency of differential port 1 obtained by simulation, and the curve marked by the black dotted line |S dd22 | represents the relationship between the differential mode reflection coefficient and frequency of differential port 2 obtained by simulation. The differential mode reflection coefficient (|S dd |)≤-10dB is the operating frequency range of the antenna.

[0059] from Figure 5 It can be seen that the operating frequency ranges of the differential port 1 and the differential port 2 of the antenna of the present invention are both 1.53 GHz-4.90 GHz, and the relative bandwidth reaches 104.8%, which means that the present invention has achieved a wider relative bandwidth and can cover multiple communication frequency bands.

[0060] Figure 6 It is a simulation curve diagram of the isolation degree of the antenna at 1 GHz-5.3 GHz in the simulation experiment 3 of the present invention. Figure 6 The horizontal axis represents the frequency in GHz, and the vertical axis represents the isolation (|S dd21|), the unit is dB. Among them, the curve marked by the red solid line |S dd21 |Represents the relationship curve between the simulated isolation and frequency.

[0061] from Figure 6 It can be seen from the figure that the antenna of the present invention has an isolation better than 48 dB in the operating frequency range of 1.53 GHz to 4.90 GHz, indicating that the present invention has achieved good isolation.

[0062] Figure 7 It is a gain simulation curve diagram of differential port 1 in the simulation experiment 4 of the present invention within the range of 1 GHz-5.3 GHz. Figure 7 The horizontal axis represents the frequency in GHz, and the vertical axis represents the gain in dBi. The curve marked with a red solid line represents the relationship curve between the gain and frequency of the differential port 1 obtained by simulation.

[0063] from Figure 7 It can be seen that within the operating frequency range of 1.53 GHz to 4.90 GHz, the antenna of the present invention has a minimum gain of 5.2 dBi and a maximum gain of 10.8 dBi, indicating that the gain of the present invention is relatively stable within the operating frequency range.

[0064] Figure 8 is the simulated radiation pattern of the antenna at four frequency points in the simulation experiment 5 of the present invention, Figure 8 The different scale values ​​on the left side of the represent the gain values ​​of different circles in the corresponding radiation pattern, in dBi. Among them, the curve marked with a black dotted line represents the main polarization curve of the E-plane obtained by simulation, the curve marked with a blue dotted line represents the cross-polarization curve of the E-plane obtained by simulation, the curve marked with a red solid line represents the main polarization curve of the H-plane obtained by simulation, and the curve marked with a green dotted line represents the cross-polarization curve of the H-plane obtained by simulation. Figure 8 (a) is the radiation pattern at 1.6 GHz, Figure 8 (b) is the radiation pattern at 3 GHz. Figure 8 (c) is the radiation pattern at 4 GHz. Figure 8 (d) is the radiation pattern at 4.7 GHz.

[0065] from Figure 8 It can be seen that the radiation patterns of the antenna of the present invention on the E plane and the H plane have good symmetry. At the high frequency of 4.7 GHz, the beam width of the radiation pattern of the antenna H plane becomes narrower. At these frequency points, the cross-polarization of the antenna is less than -30 dB, indicating that the antenna of the present invention has good radiation characteristics.

Claims

1. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch comprises an electric dipole, a magnetic dipole, a feeding structure and a box-shaped reflector; characterized in that: The electric dipole is composed of four polygonal horizontal patches of the same size and arranged rotationally symmetrically along the center of the antenna; metal semicircular rings are fixed at the rectangular grooves of two adjacent polygonal patches, and the four metal semicircular rings are symmetrically distributed along the center of the antenna.

2. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 1, characterized in that: The polygonal horizontal patch includes two rectangular grooves of the same shape and size and a cut corner, each rectangular groove is located at a diagonal position of the horizontal patch, and the depth of the rectangular groove is equal to the thickness of the horizontal patch; an isosceles right triangle is cut off the vertex angle of each horizontal patch away from the center of the antenna, the length of the two right-angled sides of the cut corner of the triangle is less than or equal to half the length of the side of the horizontal patch, and its thickness is equal to the thickness of the horizontal patch.

3. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 1, characterized in that: A rectangular notch is provided in the middle of each metal semicircular ring, and the thickness of each metal semicircular ring is equal to the thickness of the horizontal patch.

4. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 1, characterized in that: The magnetic dipole is composed of four groups of vertically arranged metal plates, each group of metal plates includes two rectangular metal plates with equal heights and perpendicular to each other, which are arranged rotationally symmetrically along the center of the antenna below the four electric dipoles.

5. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 1, characterized in that: The feeding structure consists of a cross-shaped horizontal plate and four vertical metal plates, and is placed in the middle of four polygonal horizontal patches.

6. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 4, characterized in that: Rectangular grooves are etched on both sides and the lower edge of each vertical metal plate of the feeding structure, and the depth of the rectangular grooves is equal to the thickness of the feed line; wherein the rectangular grooves on both sides have the same shape and size and are symmetrically distributed along the center of the antenna; the rectangular grooves on the lower edge have the same shape and size and are symmetrically distributed along the center of the antenna, the length of the grooves on both sides is greater than the length of the grooves on the lower edge, and the width of the grooves on both sides is less than the width of the grooves on the lower edge.

7. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 5, characterized in that: The feeding structure has four feeding ports, Port 1 at both ends of the lower edge of each pair of vertical metal plates. + and Port1 - A pair of differential ports 1 and a pair of Port2 at both ends of the lower edge of the vertical metal plate + and Port2 - A pair of differential ports 2 is formed, and each pair of differential ports is fed with differential signals with equal amplitudes and 180° phase difference, respectively. The differential signals excite the antenna through the SMA header under the floor.

8. The broadband dual-polarized magneto-electric dipole antenna with polygonal horizontal patch according to claim 1, characterized in that: The box-type reflector is a square box with an open top, which is used to reduce back radiation.

9. A broadband dual-polarized magneto-electric dipole antenna with a polygonal horizontal patch according to claim 1, characterized in that: The magnetic dipole, the electric dipole, the four metal semicircular rings and the feeding structure are all placed in the box-type reflector.

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