A triple-notch MIMO ultra-wideband antenna based on polarization diversity

Abstract

The present invention relates to a triple-notch MIMO ultra-wideband antenna. In order to solve the technical problems of existing ultra-wideband antennas having too few frequency bands for suppressing interference and lacking a notch function when addressing the interference of narrowband signals, a triple-notch MIMO ultra-wideband antenna based on polarization diversity is provided. Four unit antennas are provided on the front surface of a dielectric substrate, and four rectangular ground plates are provided on the back surface. The unit antennas include a microstrip feeder and a radiating unit connected to one end of the microstrip feeder. The radiating unit adopts a circular patch. A U-shaped groove is etched on the microstrip feeder. The four unit antennas are placed orthogonally. The four rectangular ground plates are respectively located at the four corners of the dielectric substrate. One long side and one short side of the rectangular ground plate respectively coincide with two adjacent sides of the dielectric substrate. The other end of the microstrip feeder is located within the long side range where the rectangular ground plate coincides with the edge of the dielectric substrate.

Description

Technical Field

[0001] The present invention belongs to a triple-notch MIMO ultra-wideband antenna, and in particular relates to a triple-notch MIMO ultra-wideband antenna based on polarization diversity. Background Art

[0002] With the development of wireless communication technology, new services such as voice, audio, video and data are provided. Ultra-wideband communication technology has received a lot of attention in the field of wireless communications due to its advantages such as low power consumption, high precision and low complexity.

[0003] When an ultra-wideband system is operating, multipath fading can be caused by reflections of the transmitted signal, impacting the system's normal operation. However, Multiple-Input Multiple-Output (MIMO) technology can effectively address this multipath fading issue in ultra-wideband systems. Furthermore, the introduction of MIMO technology can improve the data transmission rate, transmission quality, and channel capacity of ultra-wideband systems. Therefore, the combination of MIMO and ultra-wideband technologies is of great significance. Another key issue with ultra-wideband antennas used in these systems is interference from narrowband signals within the ultra-wideband frequency band. To address this interference, the traditional solution is to introduce filtering systems into the ultra-wideband antenna. This approach increases system complexity and cost, and is also not conducive to the miniaturization of system equipment. To address this interference, a notching function is also designed into the ultra-wideband antenna. The main methods for achieving this notching include etching geometric slots of various shapes, placing parasitic elements, and adding resonant branches.

[0004] In "A quad-element UWB-MIMO antenna with band-notch and reduced mutual coupling based on EBG structures," published in the International Journal of Antennas and Propagation in 2018, Wu W, Yuan B, Wu A, et al. proposed a circular nested four-port ultra-wideband antenna. This antenna reduces coupling between antenna elements by placing square parasitic elements on the back of a dielectric substrate. An electromagnetic bandgap (EBG) structure is introduced at the center of the front of the dielectric substrate, enabling the antenna to generate a notched band characteristic in the 4.0-5.2 GHz band. The antenna, measuring 60 mm x 60 mm, is relatively large and can only suppress interference in a single frequency band. Chinese patent publication number 104157987A, titled "A Miniaturized MIMO Ultra-Wideband Antenna," proposes a miniaturized MIMO ultra-wideband antenna consisting of two mirror-symmetrical ultra-wideband antenna elements. Miniaturization is achieved through folded microstrip lines. This antenna offers a small size and good isolation. However, with only two antenna elements, it lacks a notching function and cannot shield against interference from narrowband systems. Summary of the Invention

[0005] The present invention aims to solve the technical problems that existing ultra-wideband antennas have too few frequency bands for suppressing interference and lack of notch function when solving the interference of narrowband signals, and provides a three-notch MIMO ultra-wideband antenna based on polarization diversity.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A triple-notch MIMO ultra-wideband antenna based on polarization diversity includes a dielectric substrate; the antenna has the following features:

[0008] Four unit antennas are provided on the front surface of the dielectric substrate, and four rectangular ground plates are provided on the back surface;

[0009] The unit antenna includes a microstrip feeder and a radiation unit connected to one end of the microstrip feeder, the radiation unit adopts a circular patch, and a U-shaped groove is etched on the microstrip feeder, and the opening of the U-shaped groove faces the radiation unit;

[0010] The dielectric substrate is rectangular, and the other ends of the four microstrip feed lines are respectively arranged on the four sides of the dielectric substrate, the two microstrip feed lines on opposite sides of the dielectric substrate are parallel to each other, and the microstrip feed line on any side and the projection of the microstrip feed line on the opposite side on the side are respectively located at the two ends of the side, and starting from any microstrip feed line, the microstrip feed lines are rotated 90 degrees clockwise in the clockwise direction.

[0011] The four rectangular ground plates are respectively located at the four corners of the dielectric substrate, a long side and a short side of the rectangular ground plate respectively coincide with two adjacent sides of the dielectric substrate, the other end of the microstrip feed line is located within the edge range where the dielectric substrate and the long side of the rectangular ground plate coincide, and the microstrip feed line is connected to the rectangular ground plate.

[0012] Furthermore, an open resonant inner ring groove and an open resonant outer ring groove are opened on the radiation unit from the inside to the outside; the centers of the open resonant inner ring groove and the open resonant outer ring groove coincide, and the openings are both facing the microstrip feeder; the center of the open resonant inner ring groove deviates from the center of the radiation unit and is close to the microstrip feeder.

[0013] Furthermore, a cross-shaped branch is provided at the center of the back surface of the dielectric substrate.

[0014] Furthermore, a rectangular gap is formed on a long side of the rectangular ground plate located in the dielectric substrate, and the rectangular gap is located at the center of the long side.

[0015] Furthermore, the radius a of the radiation unit is determined by the following formula:

[0016]

[0017] Where, ε r represents the relative dielectric constant of the dielectric substrate, h represents the thickness of the dielectric substrate, k represents the transition factor, and f represents the minimum cutoff frequency.

[0018] Furthermore, the length L of the U-shaped groove notch Determined by the following formula:

[0019]

[0020] Where c is the speed of light in free space, f notch Indicates the notch center frequency.

[0021] Furthermore, the dielectric substrate is made of FR4 epoxy resin with a dielectric constant of 4.4, the dimensions of the dielectric substrate are 40 mm in length×40 mm in width×1.6 mm in thickness, and the loss tangent of the dielectric substrate is 0.02.

[0022] Furthermore, the bottom of the rectangular gap is 4 mm away from the edge of the dielectric substrate.

[0023] Furthermore, the length of the open resonant outer ring slot is greater than the length of the open resonant inner ring slot, and the gap length of the open resonant outer ring slot is greater than the gap length of the open resonant inner ring slot.

[0024] Furthermore, the length of the open resonant outer ring groove is 5mm-6mm greater than the length of the open resonant inner ring groove, and the length of the gap of the open resonant outer ring groove is 1mm-2mm greater than the length of the gap of the open resonant inner ring groove.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1. The present invention proposes a triple-notch MIMO ultra-wideband antenna based on polarization diversity, comprising a dielectric substrate with a unit antenna disposed on the front and a rectangular ground plane disposed on the back. The unit antenna further comprises a microstrip feeder and a radiating element, and the radiating element adopts a circular patch structure. The present invention adopts a monopole antenna structure as the unit antenna, achieving the antenna's ultra-wideband impedance characteristics, capable of filtering out interference from some narrowband signals, enabling ultra-wideband systems to communicate compatibly with other narrowband communication systems. The use of a rectangular ground plane can expand the antenna's operating bandwidth, and the impedance characteristics at high frequencies are improved by etching rectangular slots in the rectangular ground plane. In addition, the four unit antennas are orthogonally arranged to achieve polarization diversity characteristics, giving the antenna high isolation. By etching a U-shaped groove on the microstrip feeder, the interference received by the antenna in the 7.41-8.7 GHz frequency band is suppressed, thereby achieving the purpose of triple notches, which can effectively avoid the interference of the narrowband communication system on the ultra-wideband communication system, so that the antenna has the advantages of strong anti-interference ability and good radiation characteristics. The four unit antennas can also effectively solve the multipath fading problem in the ultra-wideband communication system, so that the antenna of the present invention can be widely used in ultra-wideband systems.

[0027] 2. The present invention etches an open resonant outer ring groove and an open resonant inner ring groove on the four radiating elements respectively, and combines this with etching a U-shaped groove on the microstrip feeder. This achieves triple-notch characteristics in the 4.0-5.7 GHz, 6.43-6.77 GHz, and 7.41-8.7 GHz frequency bands without increasing the antenna size, and can effectively avoid narrowband signal interference in these three frequency bands.

[0028] 3. The present invention introduces a cross-shaped branch on the back side of the dielectric substrate, which can further improve the isolation of the antenna.

[0029] 4. The present invention etches rectangular gaps on the rectangular ground plate, which can improve the impedance characteristics of the antenna at high frequencies.

[0030] 5. The dielectric substrate of the present invention has dimensions of 40 mm x 40 mm x 1.6 mm, which keeps the antenna dimensions small. The use of FR4 epoxy resin as the dielectric substrate reduces costs. The antenna of the present invention has broad application prospects in miniaturized portable devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a schematic structural diagram of the front side of a dielectric substrate in an embodiment of a triple-notch MIMO ultra-wideband antenna based on polarization diversity according to the present invention;

[0032] Figure 2 This is a structural schematic diagram of the back side of a dielectric substrate in an embodiment of a triple-notch MIMO ultra-wideband antenna based on polarization diversity according to the present invention;

[0033] Figure 3 This invention Figure 1 Schematic diagram of the structure of the medium unit antenna;

[0034] Figure 4 This invention Figure 3 Structure diagram of the middle radiation unit;

[0035] Figure 5 This is a simulation curve diagram of the voltage standing wave ratio of each port in the 2-12 GHz frequency band of the embodiment of the present invention;

[0036] Figure 6 This is a simulation curve diagram of the isolation between the first port and other ports in the 2-12 GHz frequency band of an embodiment of the present invention;

[0037] Figure 7 This is a simulation curve diagram of the isolation between the second port and other ports in the 2-12 GHz frequency band of the embodiment of the present invention;

[0038] Figure 8 This is the radiation pattern of an embodiment of the present invention at a frequency of 3 GHz;

[0039] Figure 9 This is the radiation pattern of an embodiment of the present invention at a frequency of 5 GHz;

[0040] Figure 10 This is the radiation pattern of an embodiment of the present invention at a frequency of 7 GHz;

[0041] Figure 11 This is the radiation pattern of an embodiment of the present invention at a frequency of 9 GHz;

[0042] Figure 12 4 is a gain simulation curve diagram of an embodiment of the present invention.

[0043] Among them: 1-microstrip feeder, 2-U-shaped slot, 3-open resonant outer ring slot, 4-open resonant inner ring slot, 5-dielectric substrate, 6-unit antenna, 7-radiating element, 8-rectangular ground plate, 9-cross branch, 10-rectangular slot. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0045] like Figure 1 and Figure 2As shown, the present invention provides a triple-notch MIMO ultra-wideband antenna based on polarization diversity. It includes a dielectric substrate 5. In this embodiment, the dielectric substrate 5 is made of FR4 epoxy resin with a dielectric constant of 4.4, which is low-cost. The dielectric substrate 5 measures 40 mm × 40 mm × 1.6 mm, and the loss tangent of the dielectric substrate 5 is 0.02, making the antenna compact and suitable for use in miniaturized portable devices. Four element antennas 6 are provided on the front of the dielectric substrate 5. The element antennas 6 are formed by copper cladding on the front of the dielectric substrate 5. Four rectangular ground planes 8 are provided on the back, with a cross-shaped branch 9 located at the center of the back of the dielectric substrate 5. The rectangular ground planes 8 and the cross-shaped branch 9 are formed by copper cladding on the back of the dielectric substrate 5. The introduction of the cross-shaped branch 9 further improves the antenna's isolation, and the use of the rectangular ground plane 8 can expand the antenna's bandwidth. The element antenna 6 includes a microstrip feeder 1 and a radiating element 7 connected to one end of the microstrip feeder 1. The radiating element 7 is a circular patch and is fed by a microstrip feeder, making it easy to manufacture. The dielectric substrate 5 is rectangular, and the other ends of the four microstrip feed lines 1 are respectively arranged on the four sides of the dielectric substrate 5. The two microstrip feed lines 1 on opposite sides of the dielectric substrate 5 are parallel to each other, and the microstrip feed line 1 on any side and the projection of the microstrip feed line 1 on the opposite side on the side are respectively located at both ends of the side, so that the positions of the unit antennas 6 on adjacent sides of the dielectric substrate 5 do not interfere with each other. Starting from any microstrip feed line 1, each microstrip feed line 1 is rotated 90° clockwise in the clockwise direction. Four rectangular ground plates 8 are located at the four corners of the dielectric substrate 5. One long side and one short side of the rectangular ground plates 8 overlap with two adjacent sides of the dielectric substrate 5, respectively. The other end of the microstrip feeder 1 is located within the long side of the rectangular ground plates 8 where they overlap with the edges of the dielectric substrate 5. Because the other end of the microstrip feeder 1 and one side of the rectangular ground plates 8 overlap with the edges of the dielectric substrate 5, the microstrip feeders 1 of the four element antennas 6 are connected to the four rectangular ground plates 8 at the edges of the dielectric substrate 5, forming a first port 11, a second port 12, a third port 13, and a fourth port 14, respectively. The four element antennas 6 and the four rectangular ground plates 8 are orthogonal to each other. Using four element antennas 6 and placing them orthogonally can further improve diversity characteristics.

[0046] As a preferred solution, a rectangular gap 10 is provided on the long side of the rectangular ground plate 8 located in the dielectric substrate 5, and the rectangular gap 10 is located at the center of the long side. Etching the rectangular gap 10 on the rectangular ground plate 8 can improve the impedance characteristics at high frequencies.

[0047] like Figure 3 and Figure 4The radiation element 7 of the unit antenna 6 is a circular patch. The radiation element 7 is provided with an open resonant inner ring slot 4 and an open resonant outer ring slot 3 from the inside out. The centers of the open resonant inner ring slot 4 and the open resonant outer ring slot 3 coincide with each other. The center of the open resonant inner ring slot 4 deviates from the center of the radiation element 7 and is close to the microstrip feeder 1. The radius a of the circular patch is determined by the following formula:

[0048]

[0049] Where, ε r represents the relative dielectric constant of the dielectric substrate 5, h represents the thickness of the dielectric substrate 5, k represents the transition factor, and f r Indicates the lowest cutoff frequency.

[0050] The four microstrip feed lines 1 are all connected to the patch serving as the radiation unit 7. The open resonant inner ring slot 4 and the open resonant outer ring slot 3 are both circular open resonant ring slots. The open resonant inner ring slot 4 and the open resonant outer ring slot 3 are offset 1-2 mm from the center of the patch toward the microstrip feed line 1 and are arranged sequentially from the inside to the outside. The length of the open resonant outer ring slot 3 is 5 mm to 6 mm longer than the length of the open resonant inner ring slot 4, and the length of the notch of the open resonant outer ring slot 3 is 1 mm to 2 mm longer than the length of the notch of the open resonant inner ring slot 4. The notch here refers to the unbroken portion of the circle, which is the notch of the ring slot, since the open resonant inner ring slot 4 and the open resonant outer ring slot 3 are not complete circles. The open resonant outer ring slot 3 can achieve a notch function in the 4.0-5.7 GHz frequency band, and the open resonant inner ring slot 4 can achieve a notch function in the 6.43-6.77 GHz frequency band. In addition, a U-shaped groove 2 is etched on the microstrip feed line 1, and the opening of the U-shaped groove 2 faces the radiation unit 7. By etching the U-shaped groove 2 on the microstrip feed line 1, the interference of the 7.41-8.7GHz frequency band can be suppressed, thereby achieving the purpose of three notches. The length L of the U-shaped groove 2 generating the notch is notch It is derived from the following formula:

[0051]

[0052] Where c is the speed of light in free space, f notch Indicates the notch center frequency.

[0053] In order to further illustrate the good performance of the triple-notch MIMO ultra-wideband antenna based on polarization diversity of the present invention, the RF characteristics of the antenna of the present invention were modeled and simulated using electromagnetic simulation software HFSS15.0. Figure 5As shown, a port voltage standing wave ratio simulation curve diagram of an embodiment of the present invention in the 2-12 GHz frequency band is shown. The connection points of the microstrip feed line 1 of the four unit antennas 6 and the rectangular ground plate 8 respectively constitute the first port 11, the second port 12, the third port 13 and the fourth port 14. VSWR (1) represents the voltage standing wave ratio simulation curve of the first port 11, VSWR (2) represents the voltage standing wave ratio simulation curve of the second port 12, and VSWR (3) represents the voltage standing wave ratio simulation curve of the third port 13. VSW R(4) represents the voltage standing wave ratio simulation curve of the fourth port 14. Within the frequency band of 3.1-10.6 GHz, the voltage standing wave ratio simulation curve of the antenna is greater than 2 at 4.0-5.7 GHz, 6.43-6.77 GHz, and 7.41-8.7 GHz, and is less than 2 at other times, indicating that the antenna can work normally within the ultra-wideband frequency band and can effectively filter out the interference of signals in the 4.0-5.7 GHz, 6.43-6.77 GHz, and 7.41-8.7 GHz frequency bands to the ultra-wideband antenna.

[0054] like Figure 6 and Figure 7 As shown, it shows the port isolation simulation curve of the embodiment of the present invention in the 2-12GHz frequency band, S 12 The isolation parameter simulation curve of the first port 11 and the second port 12 is shown in FIG. 13 The isolation parameter simulation curve of the first port 11 and the third port 13 is shown as S 14 The isolation parameter simulation curve of the first port 11 and the fourth port 14 is shown as S 23 The isolation parameter simulation curve of the second port 12 and the third port 3 is shown as S 24 The isolation parameter simulation curve of the second port 12 and the fourth port 14 is shown as S 34 The isolation parameter simulation curve of the third port 13 and the fourth port 14 is shown. 12 、S 13 、S 14 、S 23 、S 24 and S 34 It can be seen that within the range of 2-12 GHz, the isolation parameters between the four unit antennas 6 are all less than -15 dB, and the isolation is good within the entire ultra-wideband operating frequency band, and the antenna diversity characteristic is excellent.

[0055] like Figure 8 As shown, the radiation pattern of the embodiment of the present invention at 3 GHz frequency is shown. Figure 8 It can be seen that the E-plane radiation pattern of the antenna presents a directional radiation in the shape of an "8", and the H-plane radiation pattern of the antenna is approximately circular, presenting an omnidirectional radiation characteristic. Figure 9 , is the radiation pattern of the embodiment of the present invention at 5 GHz, Figure 9 It can be seen that the E-plane radiation pattern of the antenna presents a directional radiation with a shape similar to "8", and the radiation characteristics of the H-plane radiation pattern of the antenna are attenuated, but still have omnidirectional radiation characteristics. Figure 10 , is the radiation pattern of the embodiment of the present invention at 7 GHz, Figure 10 It can be seen that the E-plane radiation pattern of the antenna presents a directional radiation in the shape of an "8", and the H-plane radiation pattern of the antenna is approximately circular, presenting an omnidirectional radiation characteristic. Figure 11 , is the radiation pattern of the embodiment of the present invention at 9 GHz, Figure 11 It can be seen that the E-plane radiation pattern of the antenna presents directional radiation in the shape of an "8", and the radiation characteristics of the H-plane radiation pattern of the antenna are attenuated, but still have omnidirectional radiation characteristics. The antenna has good omnidirectional radiation characteristics throughout the entire passband.

[0056] like Figure 12 , shows the maximum gain diagram of the embodiment of the present invention in the 2-12 GHz frequency band, Figure 12 It can be seen that the antenna cannot work normally in the notched frequency band, resulting in reduced gain in the 4.0-5.7 GHz, 6.43-6.77 GHz, and 7.41-8.7 GHz bands, but has good gain in the ultra-wideband communication band.

[0057] The above embodiment proposes a three-notch MIMO ultra-wideband antenna based on polarization diversity, which has a simple structure, low cost, good radiation characteristics, strong anti-interference ability, and stable performance. A planar circular monopole antenna is used as the unit antenna 6 to realize the impedance characteristics of the ultra-wideband antenna. By etching an open resonant inner ring groove 4 and an open resonant outer ring groove 3 on the patch serving as the radiation unit 7, and etching a U-shaped groove 2 on the microstrip feeder 1, the antenna of the present invention produces an impedance characteristic, filters out interference from the three narrowband signal frequency bands, and realizes mutual compatibility and cooperative communication between the ultra-wideband system and other narrowband communication systems.

[0058] The present invention adopts the method of etching grooves to generate notch characteristics, which can effectively filter out interference from different narrowband communications, realize the mutual compatibility and cooperative communication between the ultra-wideband system and other narrowband communication systems, has a simple structure, replaces the filter design, realizes the notch function without additionally increasing the antenna size, reduces the design cost and complexity, is easy to process and easy to produce, adopts a planar structure, is relatively small in size, and has a compact structure, which is easy to integrate with radio frequency front-end circuits and miniaturized mobile terminals, has high practical value, and can be applied to various ultra-wideband communication systems.

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A triple-notch MIMO ultra-wideband antenna based on polarization diversity, comprising a dielectric substrate (5); characterized in that: Four unit antennas (6) are provided on the front surface of the dielectric substrate (5), and four rectangular grounding plates (8) are provided on the back surface; The unit antenna (6) comprises a microstrip feeder (1) and a radiation unit (7) connected to one end of the microstrip feeder (1); the radiation unit (7) is a circular patch; a U-shaped groove (2) is etched on the microstrip feeder (1); and the opening of the U-shaped groove (2) faces the radiation unit (7); The dielectric substrate (5) is rectangular, and the other ends of the four microstrip feed lines (1) are respectively arranged on the four sides of the dielectric substrate (5); the two microstrip feed lines (1) on opposite sides of the dielectric substrate (5) are parallel to each other, and the microstrip feed line (1) on any side and the projection of the microstrip feed line (1) on the opposite side on the side are respectively located at two ends of the side; with any microstrip feed line (1) as a starting point, each microstrip feed line (1) is rotated 90 degrees clockwise in a clockwise direction; The four rectangular ground plates (8) are respectively located at the four corners of the dielectric substrate (5); a long side and a short side of the rectangular ground plate (8) respectively coincide with two adjacent sides of the dielectric substrate (5); the other end of the microstrip feed line (1) is located within the edge range where the dielectric substrate (5) and the long side of the rectangular ground plate (8) coincide, and the microstrip feed line (1) is connected to the rectangular ground plate (8); An open resonant inner ring slot (4) and an open resonant outer ring slot (3) are provided on the radiation unit (7) from the inside out; the centers of the open resonant inner ring slot (4) and the open resonant outer ring slot (3) coincide with each other, and both openings face the microstrip feeder (1); the center of the open resonant inner ring slot (4) deviates from the center of the radiation unit (7) and is close to the microstrip feeder (1); The length of the open resonant outer ring slot (3) is greater than the length of the open resonant inner ring slot (4), and the gap length of the open resonant outer ring slot (3) is greater than the gap length of the open resonant inner ring slot (4); The rectangular ground plate (8) is provided with a rectangular gap (10) on a long side located inside the dielectric substrate (5), and the rectangular gap (10) is located at the center of the long side.

2. The triple-notch MIMO ultra-wideband antenna based on polarization diversity according to claim 1, characterized in that: The length of the open resonant outer ring groove (3) is 5mm-6mm greater than the length of the open resonant inner ring groove (4), and the gap length of the open resonant outer ring groove (3) is 1mm-2mm greater than the gap length of the open resonant inner ring groove (4).

3. The triple-notch MIMO ultra-wideband antenna based on polarization diversity according to claim 1 or 2, characterized in that: A cross-shaped branch (9) is provided at the center of the back side of the dielectric substrate (5).

4. The triple-notch MIMO ultra-wideband antenna based on polarization diversity according to claim 3, characterized in that: The bottom of the rectangular gap (10) is 4 mm away from the edge of the dielectric substrate (5).

5. The triple-notch MIMO ultra-wideband antenna based on polarization diversity according to claim 4, characterized in that: The radius a of the radiation unit (7) is determined by the following formula: Where, ε r represents the relative dielectric constant of the dielectric substrate (5), h represents the thickness of the dielectric substrate (5), k represents the transition factor, and f r Indicates the lowest cutoff frequency.

6. The triple-notch MIMO ultra-wideband antenna based on polarization diversity according to claim 5, characterized in that: The length L of the U-shaped groove (2) notch Determined by the following formula: Where c is the speed of light in free space, f notch Indicates the notch center frequency.

7. The triple-notch MIMO ultra-wideband antenna based on polarization diversity according to claim 6, characterized in that: The material of the dielectric substrate (5) is FR4 epoxy resin with a dielectric constant of 4.

4. The dimensions of the dielectric substrate (5) are 40 mm in length×40 mm in width×1.6 mm in thickness. The loss tangent angle of the dielectric substrate (5) is 0.02.

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