Ultra-wideband notch antenna for 5G millimeter wave communication system

Abstract

The invention discloses an ultra-wideband notch antenna for a 5G millimeter wave communication system. The ultra-wideband notch antenna comprises a first metal layer, a second metal layer and a third metal layer, the second metal layer is a metal ground, the third metal layer is a feed part, and the first metal layer is a radiation part and comprises a radiation patch and a parasitic patch; the radiation patch is of a dipole structure and comprises two dipole arms, and the tail end of each dipole arm is bent inwards on the side away from the symmetry axis. The parasitic patches comprise a first parasitic patch and a second parasitic patch, the first parasitic patch is located on the outer side of the tail end of each dipole arm and used for exciting current in the same direction as the dipole arm in a working frequency band and improving impedance matching of the antenna, and the second parasitic patch is located between the tail ends of the dipole arms and used for exciting current in the same direction as the dipole arm in the working frequency band and improving impedance matching of the antenna. And the central frequency point of the required filtering frequency band is equivalent to a half-wavelength resonator, and when the antenna works in the frequency band range, the current on the surface of the antenna is concentrated on the parasitic patch, so that impedance mismatch is caused, and effective filtering of the frequency band is realized.

Description

Technical Field

[0001] The present invention belongs to the field of wireless communication technology and relates to a 5G millimeter wave communication system antenna, and in particular to an ultra-wideband notch antenna for a 5G millimeter wave communication system. Background Art

[0002] With the rapid development of modern wireless communication systems, the demand for high-speed, high-capacity and low-latency communication frequencies is increasing. The millimeter wave band has attracted widespread attention due to its abundant available frequency resources. For example, the N257 (26.5–29.5 GHz), N258 (24.25–27.5 GHz), N259 (39.5–43.5 GHz) and N260 (37–40 GHz) bands have obtained 5G millimeter wave communication licenses. In order to improve system compatibility, the communication system needs to cover as many frequency bands as possible. Therefore, the design of ultra-wideband millimeter wave antennas that can cover multiple frequency bands has important research value and application prospects.

[0003] However, the spectrum covered by ultra-wideband antennas is extremely wide, and in practical applications, they will be interfered by certain narrowband frequency bands, which has a significant impact on the overall performance of the system. To solve this problem, it is usually necessary to effectively filter the interfering frequency bands. Traditional filtering methods achieve this goal by adding filters to the antenna, but this solution often leads to an increase in the size of the antenna, thus limiting the realization of miniaturization. In contrast, ultra-wideband notch antennas filter within a specific frequency band through their inherent notch structure, which can effectively suppress interference and optimize the utilization of spectrum resources. Therefore, they have attracted much attention in recent years.

[0004] In 2023, scholars such as Qingquan Tan and Kuikui Fan proposed a compact ultra-wideband planar folded dipole antenna. Based on the half-wavelength dipole, the antenna reduces the input resistance of the antenna by placing two half-wavelength dipoles in parallel, achieves broadband impedance matching, and feeds the antenna unit by coupling slot feeding. The capacitance provided by the coupling slot can offset the inductance generated by the parallel folded dipole, thereby improving the impedance matching in the low-frequency band. On this basis, the end of the dipole is folded, which greatly reduces the size of the antenna. The final antenna unit is 0.53λ c ×0.53λ c ×0.15λ c (where λ c An impedance bandwidth of better than 64% is achieved within a size of (free space wavelength at center frequency).

[0005] In 2024, scholars such as Jiawang Li and Yuanwei Zhu proposed a millimeter-wave ultra-wideband antenna with a hybrid resonant mode. The antenna unit combines multiple resonant modes, including slot resonant mode, patch resonant mode, quasi-monopole resonant mode, and microstrip line resonant mode with open terminals. By flexibly designing the resonant frequency of each mode, the ultra-wideband performance of the antenna unit was successfully achieved. After processing and actual measurement verification, the antenna unit achieved an impedance bandwidth of more than 69.4%. Both of the above units achieve ultra-wideband operation in the millimeter-wave frequency band, but they do not have a notch structure themselves, so it is difficult to effectively filter the interference frequency band without loading a filter.

[0006] In 2023, Z. Zhao and other scholars proposed a miniaturized antenna with multi-notch characteristics. The antenna realizes notch characteristics in five different frequency bands through the notch branches in the center of the radiation patch, the spiral parasitic patches on both sides of the feed line, and the long parasitic patches and short parasitic patches at the bottom of the dielectric plate. The test results show that the bandwidth of the antenna covers 2.56-12.7GHz, and the notch frequency bands of the antenna are 2.58-3.21GHz, 4.05-4.29GHz, 5-5.64GHz, 8.60-9.05GHz, and 9.20-10.32GHz, respectively. The notch characteristics of the 4.05-4.29GHz and 8.60-9.05GHz bands are realized by the spiral parasitic patches on both sides of the feed line, and the notch characteristics of the 5-5.64GHz and 9.20-10.32GHz bands are realized by the long parasitic patches and short parasitic patches at the bottom of the dielectric plate, respectively.

[0007] In 2024, H. Gan and other scholars proposed a high-gain array antenna loaded with parasitic patches. In order to achieve broadband impedance matching, the antenna is loaded with three parasitic patches. After loading the first square parasitic patch above the radiating patch, the relative bandwidth of the antenna is expanded from 1.91% to 6.38%, and then through the optimization of the slot structure, the bandwidth is expanded to 20.85%. Finally, two layers of rectangular patches are loaded to increase the antenna bandwidth while avoiding the warping problem of the antenna dielectric board. The test results show that the -10dB bandwidth of the 8×8 array covers 85.2-110GHz, and the relative bandwidth is better than 26.6%.

[0008] Through the above analysis, the existing technology mainly has the following deficiencies:

[0009] (1) The bandwidth of existing millimeter-wave ultra-wideband antennas is relatively narrow. The relative bandwidth of most antennas is less than 70%, and there is still much room for expansion.

[0010] (2) Some existing millimeter-wave ultra-wideband antennas do not have a notch structure and cannot effectively avoid the adverse effects of interference frequency bands on system performance.

[0011] (3) Most existing ultra-wideband notch antennas operate at low frequencies and face great adaptability challenges when used in antenna arrays, especially tightly coupled array antennas. Summary of the invention

[0012] In order to overcome the above-mentioned shortcomings of the narrow bandwidth of the millimeter wave antenna in the prior art and the inability to effectively avoid the influence of the interference frequency band, and the low operating frequency of most existing ultra-wideband notch antennas, and the low adaptability when applied to antenna arrays, especially tightly coupled array antennas, the purpose of the present invention is to provide an ultra-wideband notch antenna for a 5G millimeter wave communication system, which can cover the 15.97-45.55GHz frequency band, avoiding the problem of arranging multiple antennas to adapt to different 5G millimeter wave communication frequency bands. At the same time, by loading a parasitic patch, it acts as a half-wavelength resonator at the center frequency of the interference frequency band. When the antenna operates within the interference frequency band, the surface current of the antenna will be concentrated on the parasitic patch, resulting in impedance mismatch, thereby achieving effective filtering of the interference frequency band. The antenna has a simple structure, is easy to process, and has important practical engineering application value.

[0013] In order to achieve the above object, the technical solution adopted by the present invention is:

[0014] An ultra-wideband notch antenna for a 5G millimeter wave communication system, comprising a first metal layer, a second metal layer and a third metal layer;

[0015] The first metal layer is a radiation part, including a radiation patch and a parasitic patch; the radiation patch is a dipole structure, including two dipole arms symmetrical along an axis, and the end of each dipole arm is bent inward on a side away from the symmetry axis; the parasitic patch includes a first parasitic patch and a second parasitic patch, the first parasitic patch is located outside the end of each dipole arm, and is used to excite a current in the same direction as the dipole arm within the working frequency band, and the second parasitic patch is located between the ends of each dipole arm, and is used to achieve filtering of a certain frequency band of the working frequency band;

[0016] The second metal layer is a metal ground and is electrically connected to the radiation patch;

[0017] The third metal layer is a feeding part, which feeds the radiation patch through the H-shaped coupling slot etched on the second metal layer.

[0018] In one embodiment, the antenna further comprises a first dielectric layer, an adhesive layer, and a second dielectric layer;

[0019] The first metal layer is located on the upper surface of the first dielectric layer, and the second metal layer and the third metal layer are located on the upper surface and the lower surface of the second dielectric layer respectively; the adhesive layer is used to bond the first dielectric layer and the second dielectric layer.

[0020] In one embodiment, three metal holes are provided in the unbent portion of each dipole arm, and the metal holes penetrate through the first dielectric layer and the adhesive layer and are connected to the second metal layer.

[0021] In one embodiment, the second metal layer covers the entire upper surface of the second dielectric layer, and an H-type coupling slot symmetrical about its center is etched thereon, the H-type coupling slot consists of a main slot and two slot branches, the main slot is opposite to the projection of the symmetry axis of the two dipole arms, the two slot branches are vertically connected to the main slot near the end, and the width of the main slot is greater than the width of the slot branches.

[0022] In one embodiment, the slot branch is opposite to the projection of the bending parts of the two dipole arms.

[0023] In one embodiment, the third metal layer is a microstrip feed line designed based on a T-junction power divider, and its two feed line branch projections are located between the connection between the second metal layer and the radiation patch and the slot branch, and are parallel to the slot branch, and the end is a T-shaped structure.

[0024] In one embodiment, the dipole arms are designed to be of equal width, with rounded corners at the bends, and the distances between the two ends of a dipole arm and the second parasitic patch therebetween are equal.

[0025] In one embodiment, there are four first parasitic patches, which excite a current in the same direction as the dipole arm in the strip.

[0026] In one embodiment, there are two second parasitic patches, and the length of the second parasitic patches is used to adjust the in-band filtering frequency band. When the length of the second parasitic patches increases, the filtering frequency band moves toward low frequency.

[0027] In one embodiment, the total length of the two second parasitic patches is half the wavelength of the microstrip line at the center frequency of the filtering frequency band.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] First, the present invention loads a first parasitic patch on the side of each dipole arm, including but not limited to a rectangular, semicircular ring, etc., and is not limited to this loading method. More patches can be used to obtain better results. These first parasitic patches excite currents in the same direction as the dipole arm within the working frequency band, further improving the performance of the antenna. When the antenna is not loaded with a resonant structure, a relative bandwidth of 87.7% can be obtained. Compared with other millimeter-wave ultra-wideband antennas, it has a wider bandwidth.

[0030] Second, the present invention loads a second parasitic patch between the ends of the two dipole arms, including but not limited to a rectangular, T-shaped, etc. The principle of achieving notch through this method is that these second parasitic patches are equivalent to a half-wavelength resonator at the center frequency of the corresponding filtering frequency band. When the antenna works within this frequency band, the surface current of the antenna will be concentrated on the second parasitic patch, resulting in impedance mismatch, thereby achieving filtering of this frequency band. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 A three-dimensional structural schematic diagram of the millimeter-wave ultra-wideband notch antenna of the present invention is given.

[0032] Figure 2 A top view of the antenna of the present invention is given, showing the structures of the first and second metal layers.

[0033] Figure 3 A top view of the antenna of the present invention is given, showing the structure of the first metal layer.

[0034] Figure 4 A top view of the antenna of the present invention is given, showing the structures of the second and third metal layers.

[0035] Figure 5 The reflection coefficient simulation result diagram of the antenna of the present invention is given.

[0036] Figure 6 The influence of whether the first parasitic patch of the antenna of the present invention is loaded on the antenna reflection coefficient is given.

[0037] Figure 7 The influence of the length of the second parasitic patch of the antenna of the present invention on the reflection coefficient of the antenna is given.

[0038] Figure 8 The gain simulation result diagram of the antenna of the present invention is given.

[0039] Fig. 9 The simulated radiation patterns of the antenna of the present invention at 24 and 41.4 GHz are given; among them, (a) is the E-plane simulated radiation pattern of the antenna at 24 GHz; (b) is the H-plane simulated radiation pattern of the antenna at 24 GHz; (c) is the E-plane simulated radiation pattern of the antenna at 41.4 GHz; (d) is the H-plane simulated radiation pattern of the antenna at 41.4 GHz. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] In view of the shortcomings of some existing millimeter wave antennas that have narrow bandwidths and cannot effectively avoid the influence of interference frequency bands, the present invention proposes a millimeter wave ultra-wideband notch antenna.

[0042] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, the antenna of the present invention mainly comprises a first metal layer 1, a second metal layer 5 and a third metal layer 7. It is easy to understand that when the present invention refers to the first layer, the second layer and the like, it means that these layers are different layers along the up and down direction.

[0043] The first metal layer 1 is the radiation part of the present invention, including a radiation patch 8 and a parasitic patch. The radiation patch 8 is a dipole structure, including two dipole arms symmetrical along the axis, and the end of each dipole arm is bent inward on the side away from the symmetry axis to form an unclosed semicircular ring structure. The parasitic patch is an important feature of the present invention, and the parasitic patch of the present invention includes a first parasitic patch 9 and a second parasitic patch 10.

[0044] Among them, the first parasitic patch 9 is located on the outside of the end of each dipole arm, and the outside here refers to the side away from the bending direction, that is, the side away from the symmetry axis of the single dipole arm. By loading the first parasitic patch 9 here, a current in the same direction as the dipole arm can be excited within the working frequency band, thereby changing the current distribution of the radiation part. In addition, the coupling between the first parasitic patch 9 and the radiation patch 8 helps to smooth the reactance change of the antenna at high frequencies and further optimize the impedance matching performance of the antenna.

[0045] The second parasitic patch 10 is located between the ends of each dipole arm, that is, it is "sandwiched" by the two ends of the dipole arm, but there is a gap between the dipole arm. By loading the second parasitic patch 10 here, it is equivalent to a half-wavelength resonator at the center frequency of the filtering band. When the antenna works within the corresponding frequency band, the surface current of the antenna will be concentrated on the second parasitic patch 10, thereby exciting a strong resonance phenomenon. This resonance will cause the antenna impedance mismatch, so that the energy cannot be effectively radiated into the free space, and finally the filtering function of this frequency band is realized.

[0046] The second metal layer 5 is the metal ground of the present invention, which is electrically connected to the radiation patch 8 , and the third metal layer 7 is the feeding part of the present invention, which is configured to be able to feed the radiation patch 8 through the H-type coupling slot 11 etched on the second metal layer 5 .

[0047] In a specific embodiment of the present invention, two dielectric layers are provided, namely, a first dielectric layer 3 and a second dielectric layer 6, to carry the metal layer. The first metal layer 1 is printed on the upper surface of the first dielectric layer 3, the second metal layer 5 is printed on the upper surface of the second dielectric layer 6, and the third metal layer 7 is printed on the lower surface of the second dielectric layer 6. For example, the second metal layer 5 can also be printed on the lower surface of the first dielectric layer 3. In the present invention, the first metal layer 1, the second metal layer 5 and the third metal layer 7 are arranged in sequence from top to bottom, so the first dielectric layer 3 is located above the second dielectric layer 6, and the two can be bonded together by the adhesive layer 4.

[0048] In a specific embodiment of the present invention, a number of metal holes 2 are evenly arranged in a row in the middle position of each dipole arm, that is, in the central area of ​​the unbent part, to electrically connect the radiation patch 8 and the second metal layer 5, so as to achieve a relatively uniform distribution of resonance points within the frequency band. The present invention designs three metal holes 2 to enable the antenna to exhibit the potential for ultra-wideband performance. The number of metal holes 2 has a great influence on the antenna performance. If the number is changed, the antenna needs to be readjusted. This embodiment designs three metal holes 2 on each dipole arm, and a total of six metal holes 2 on the two dipole arms. Each metal hole 2 passes through the first dielectric layer 3 and the adhesive layer 4 to connect the dipole arm to the second metal layer 5.

[0049] In a specific embodiment of the present invention, the second metal layer 5 covers the entire surface of the dielectric layer in which it is located, and an H-type coupling gap 11 is etched in the middle position. The overall structure of the H-type coupling gap 11 is symmetrical about the center of the second metal layer 5, and is composed of a main gap and two gap branches. The main gap and the gap branches are both long strips. The width of the main gap is greater than the width of the gap branches, and is vertically connected to the gap branches. The length direction of the main gap is parallel to the symmetry axis of the two dipole arms, and it is best to be projected onto the symmetry axis. The two gap branches are connected at a position close to the end of the main gap, that is, the main gap can continue to extend a part at the connection. The specific connection position of the gap branch can be controlled to be opposite to the projection of the bending point of the two dipole arms.

[0050] In a specific embodiment of the present invention, the third metal layer 7 is a microstrip feed line designed based on a T-junction power divider, and its two feed line branch projections are located between the connection between the second metal layer 5 and the radiation patch 8 and the gap branch, and are parallel to the gap branch, and the end is a T-shaped structure.

[0051] In a specific embodiment of the present invention, the dipole arms are designed to be of equal width, and the bends are rounded to improve the reflection coefficient. The two ends of a dipole arm are equidistant from the second parasitic patch 10 therebetween. For example, the spacing here can range from 0.22 mm to 0.3 mm.

[0052] In a specific embodiment of the present invention, there are four first parasitic patches 9, which excite the current in the same direction as the dipole arm in the band. To achieve a better excitation effect, the length of the first parasitic patch 9 should be adjusted according to the impedance change of the antenna. When designing based on simulation software, the influence of first parasitic patches of different lengths on the smoothness of the antenna input impedance curve can be analyzed by parameter scanning. At the same time, it is necessary to comprehensively consider the situation that the high-frequency reflection coefficient may deteriorate due to the excessive length of the patch. Finally, according to the simulation analysis results, a suitable patch length is selected to further improve the impedance matching of the antenna.

[0053] The specific shape of the first parasitic patch 9 loaded in the present invention includes but is not limited to a rectangle, a semicircular ring, etc., and the number of the first parasitic patch 9 can be greater to obtain a better effect. These patches excite currents in the same direction as the dipole arm within the working frequency band, thereby improving the performance of the antenna.

[0054] In a specific embodiment of the present invention, there are two second parasitic patches 10 , and the length of the second parasitic patch 10 is used to adjust the in-band filtering frequency band. When the length of the second parasitic patch 10 increases, the filtering frequency band moves toward low frequency.

[0055] In a specific embodiment of the present invention, the total length of the two second parasitic patches 10 is used to adjust the in-band filtering frequency band, which is usually half the wavelength of the microstrip line at the center frequency of the filtering frequency band.

[0056] The specific shape of the second parasitic patch 10 loaded in the present invention includes but is not limited to a rectangular shape, a T-shape, etc. The principle of achieving notch through this method is that these second parasitic patches 10 are equivalent to a half-wavelength resonator at the center frequency of the corresponding filtering frequency band. When the antenna works within this frequency band, the surface current of the antenna will be concentrated on the parasitic patch, resulting in impedance mismatch, thereby achieving filtering of this frequency band.

[0057] Taking the dielectric layer using Taconic TSM-DS3, the bonding layer using FR27-0040-43F, and the metal layer using copper as an example, the electromagnetic simulation software HFSS is used for simulation optimization. The detailed dimensions of the antenna unit are shown in Table 1 (the parameters in the table are shown in the appendix of the manual). Figure 3 and Figure 4 ).

[0058]

[0059] Figure 5 This is a diagram of the reflection coefficient simulation result of the antenna unit of the present invention. It can be seen that the frequency bands with a reflection coefficient less than -10dB are 16.04-31.98GHz and 37.43-45.60GHz, and filtering is achieved in the 31.98-37.43GHz frequency band.

[0060] Figure 6The figure shows the influence of the first parasitic patch 9 of the antenna unit of the present invention on the antenna reflection coefficient, which directly reflects that the impedance matching of the antenna can be improved by the first parasitic patch 9 in the design, and this improvement is more obvious at high frequencies.

[0061] Figure 7 The figure shows the influence of the total length 2*ljs2 of the second parasitic patch 10 of the antenna unit of the present invention on the antenna reflection coefficient, which intuitively reflects the frequency band in which the filtering effect can be achieved by adjusting the length of the second parasitic patch in the design. The total length 2*ljs2 of the parasitic patch is generally taken as half the wavelength of the microstrip line at the center frequency of the suppressed frequency band.

[0062] Figure 8 3 is a gain simulation result diagram of the antenna unit of the present invention. It can be seen that the loading of the second parasitic patch achieves a reduction in the gain within the 31.98-37.43 GHz frequency band, further verifying the filtering effect of the structure.

[0063] Fig. 9 (a)-(b) show the simulated radiation patterns of the antenna unit of the present invention at 24 GHz E-plane and H-plane respectively. It can be seen from the figures that the radiation patterns have good symmetry, and the cross-polarization of the E-plane and the H-plane are both less than -50 dB.

[0064] Fig. 9 (c)-(d) show the simulated radiation patterns of the antenna unit of the present invention at 41.5 GHz E-plane and H-plane respectively. It can be seen from the figures that the radiation patterns have good symmetry, and the cross-polarization of the E-plane and the H-plane are both less than -50 dB.

[0065] The antenna is loaded with parasitic patches on the side of the radiating patch. These parasitic patches excite currents in the same direction as the antenna radiating arm within the working frequency band, further improving the performance of the antenna. When the antenna is not loaded with a resonant structure, a relative bandwidth of 87.7% can be obtained. At the same time, by loading the parasitic patches, it acts as a half-wavelength resonator at the center frequency of the interference frequency band. When the antenna operates within the interference frequency band, the current on the antenna surface will be concentrated on the parasitic patches, resulting in impedance mismatch, thereby achieving effective filtering of the interference frequency band. The antenna has a simple structure and is easy to process, and has important practical engineering application value.

[0066] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. An ultra-wideband notch antenna for a 5G millimeter wave communication system, characterized in that: It comprises a first metal layer (1), a second metal layer (5) and a third metal layer (7); The first metal layer (1) is a radiation part, comprising a radiation patch (8) and a parasitic patch; the radiation patch (8) is a dipole structure, comprising two dipole arms symmetrical along an axis, the end of each dipole arm being bent inward on a side away from the axis of symmetry; the parasitic patch comprises a first parasitic patch (9) and a second parasitic patch (10), the first parasitic patch (9) being located outside the end of each dipole arm and being used to excite a current in the same direction as the dipole arm within the working frequency band, and the second parasitic patch (10) being located between the ends of each dipole arm and being used to achieve filtering of a certain frequency band within the working frequency band; The second metal layer (5) is a metal ground and is electrically connected to the radiation patch (8); The third metal layer (7) is a feeding part, which feeds the radiation patch (8) through an H-shaped coupling gap (11) etched on the second metal layer (5).

2. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 1, characterized in that: The antenna further comprises a first dielectric layer (3), an adhesive layer (4) and a second dielectric layer (6); The first metal layer (1) is located on the upper surface of the first dielectric layer (3), and the second metal layer (5) and the third metal layer (7) are located on the upper surface and the lower surface of the second dielectric layer (6), respectively; and the adhesive layer (4) is used for bonding the first dielectric layer (3) and the second dielectric layer (6).

3. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 2, characterized in that: Three metal holes (2) are arranged on the unbent portion of each dipole arm, and the metal holes (2) penetrate the first dielectric layer (3) and the adhesive layer (4) and are connected to the second metal layer (5).

4. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 2, characterized in that: The second metal layer (5) covers the entire upper surface of the second dielectric layer (6), and an H-shaped coupling slot (11) symmetrical about its center is etched thereon, the H-shaped coupling slot (11) consisting of a main slot and two slot branches, the main slot is opposite to the projection of the symmetry axis of the two dipole arms, the two slot branches are vertically connected to the main slot at a position close to the end, and the width of the main slot is greater than the width of the slot branch.

5. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 4, characterized in that: The slot branch is opposite to the projection of the bending parts of the two dipole arms.

6. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 4, characterized in that: The third metal layer (7) is a microstrip feeder designed based on a T-junction power divider, and its two feeder branch projections are located between the connection between the second metal layer (5) and the radiation patch (8) and the slot branch, and are parallel to the slot branch, with the ends being a T-shaped structure.

7. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 1, characterized in that: The dipole arms are designed to be of equal width, with rounded corners at the bends, and the distances between the two ends of a dipole arm and the second parasitic patch (10) therebetween are equal.

8. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to any one of claims 1 to 7, characterized in that: There are four first parasitic patches (9) in total, which excite a current in the same direction as the dipole arm in the band.

9. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to any one of claims 1 to 7, characterized in that: There are two second parasitic patches (10) in total. The length of the second parasitic patches (10) is used to adjust the in-band filtering frequency band. When the length of the second parasitic patches (10) increases, the filtering frequency band moves toward a low frequency.

10. The ultra-wideband notch antenna for a 5G millimeter wave communication system according to claim 9, characterized in that: The total length of the two second parasitic patches (10) is half the wavelength of the microstrip line at the center frequency point of the filtering frequency band.

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