Dual-band dual-polarized shared aperture antenna with mode diversity

Abstract

The application discloses a dual-frequency dual-polarization shared-aperture antenna with mode diversity, belongs to the technical field of wireless communication and antennas, and is composed of a metal floor, Vivaldi antenna left and right ridge metal radiators, a tapered monopole antenna, a dielectric polarization converter and two coaxial feeding wires, and adopts side-positioned coaxial line feeding; wherein the metal radiators and the tapered monopole radiator are a composite integrated structure; the tapered monopole radiator is hollow inside, and the metal radiators are two and symmetrically placed at the bottom of the tapered monopole radiator. The antenna realizes dual-frequency dual-polarization, can cover microwave and millimeter wave frequency bands, two frequency bands are independent and have a wide frequency band, and simultaneously have an omnidirectional radiation mode and a directional radiation mode; the dual-frequency dual-polarization antenna with multiple modes and diversity has a good stable omnidirectional radiation pattern in a microwave band, is a circularly polarized radiation mode in a millimeter wave band, has a high-gain directional radiation capacity, and can be applied to UWB, 5G millimeter wave communication and various applications.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications and antennas, and relates to a dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity. Background Art

[0002] With the rapid development of modern wireless communication technology, communication services are covering an increasingly wide range of areas. 5G utilizes both the sub-6GHz microwave band and the millimeter wave band. Currently, microwave frequency resources are becoming increasingly scarce. Millimeter waves offer wider bandwidth coverage, paving the way for 5G communications to achieve transmission speeds dozens of times faster than today's speeds, while also laying the foundation for the long-distance transmission capabilities of 6G communications.

[0003] Omnidirectional antennas, with their advantages of omnidirectional coverage, cost-effectiveness, ease of installation and maintenance, strong compatibility, and support for multi-device connectivity, play a vital role in providing wide wireless signal coverage, saving energy, and enhancing network scalability. They are particularly well-suited for wireless communication environments requiring wide coverage and multi-user access. Circularly polarized antennas, with their resistance to polarization mismatch and multipath fading, can improve communication quality. Since millimeter-wave signals are susceptible to multipath effects, circularly polarized antennas are well-suited for millimeter-wave communications, enhancing the quality of 5G millimeter-wave communications. Therefore, circularly polarized antennas hold great promise for application in 5G millimeter-wave technology.

[0004] Combining the advantages of omnidirectional antennas and circularly polarized antennas, the present invention aims to design a shared aperture antenna that can achieve omnidirectional radiation in the microwave band and directional radiation in the millimeter wave band. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a dual-polarized shared aperture antenna that covers both microwave and millimeter wave application frequency bands. It can cover multiple application frequency bands such as 4G LTE, 5G Sub-6GHz, 5G n257 and n258, WIFI, UWB, etc., and can be particularly applied to various applications such as UWB and 5G millimeter wave communications.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A dual-frequency dual-polarization shared aperture antenna with pattern diversity, the dual-frequency dual-polarization shared aperture antenna includes a conical monopole metal radiator and its extended outer ring, the left and right ridges of the Vivaldi antenna metal radiator, a dielectric polarization converter, a reflective floor, and two coaxial feeding connections. The main body of the dual-frequency dual-polarization shared aperture antenna is a three-part composite integrated structure, including the left and right ridge metal radiators of the Vivaldi antenna and the conical monopole radiator. The conical monopole radiator is hollow inside and serves as a radiator in the microwave band. There are two Vivaldi antenna metal radiators, both made of metal, symmetrically placed at the bottom of the conical monopole radiator, serving as radiators in the millimeter wave band, and side coaxial line feeding is used to replace the traditional microstrip line coupling feeding method. Specifically:

[0008] The reflective floor is a square metal floor 1. A hollowed-out conical monopole metal radiator is provided above the square metal floor 1. The dielectric polarization converter 2 is placed directly above the conical monopole antenna 5. A via A8 is provided on the square metal floor 1.

[0009] The conical monopole metal radiator is a conical monopole antenna 5. An extended outer ring is provided on the top of the conical monopole antenna 5, that is, a metal ring extends horizontally from the edge of the conical monopole antenna 5 to fix the nylon column during processing to maintain structural stability.

[0010] The metal radiator of the Vivaldi antenna is arranged inside the conical monopole antenna 5 and includes two symmetrical structures, namely the right ridge 3 of the Vivaldi antenna and the left ridge 4 of the Vivaldi antenna.

[0011] The coaxial feeder has two connections: coaxial line A6 located directly below the conical monopole antenna 5 and coaxial line B7 on the side. Coaxial line A6 is welded to the conical monopole antenna 5 through via 8A in the metal floor 1. Specifically, the inner conductor of coaxial line A6 is welded to the conical monopole antenna 5 through via 8A, and the outer conductor of coaxial line A6 is connected to the metal floor 1. The inner conductor of coaxial line B7 is connected to the left ridge 4 of the Vivaldi antenna through vias B9 and C10. The outer conductor of coaxial line B7 is connected to the right ridge 3 of the Vivaldi antenna and the outer wall of the conical monopole antenna 5.

[0012] Furthermore, a via A8 is provided at the center of the metal floor 1. A via B9 is provided on the outer wall of the conical monopole antenna 5. A via C10 is provided on the right ridge 3 of the Vivaldi antenna. The vias B9 and C10 are at the same horizontal position.

[0013] Further, the Vivaldi antenna right ridge 3 and the Vivaldi antenna left ridge 4 are a pair of irregular metal blocks, the thicknesses of which are the same, including the upper conical opening-shaped Vivaldi antenna and the lower trapezoidal connecting metal block matched with the side wall and the bottom of the conical monopole antenna 5, and a gap is left between the two, the Vivaldi antenna right ridge 3 is provided with a via C10, and the materials of the two are the same as the material of the conical monopole antenna, which can be processed by copper or aluminum metal materials, and air is used to replace the dielectric substrate, and the specific structure and position of the two are that the Vivaldi antenna right ridge 3 and the Vivaldi antenna left ridge 4 are symmetrically placed at the bottom center position of the conical radiator, and both are connected with the inner wall of the conical monopole antenna 5.

[0014] Further, the specific structure of the dielectric polarization converter is that a plurality of dielectric strips are collectively composed, and each dielectric strip is at an angle of 45° with the x-axis. Specifically, the dielectric polarization converter is composed of a plurality of dielectric blocks of different lengths arranged in the same direction at the same interval, and the linearly polarized wave emitted by the Vivaldi antenna right ridge 3 and the Vivaldi antenna left ridge 4 is converted into a circularly polarized wave by the dielectric polarization converter, and both the side wall of the conical monopole antenna and the dielectric polarization converter can improve the gain of the Vivaldi antenna in the millimeter wave frequency band.

[0015] Further, the Vivaldi antenna right ridge 3, the Vivaldi antenna left ridge 4 and the conical monopole antenna 5 can be processed by integrated 3D printing technology, which avoids the errors that may be caused by the combination and fixation of two parts, and improves the stability of the model. That is, the Vivaldi antenna does not need to be printed on the dielectric substrate and does not need to consider how to fix it on the conical monopole antenna.

[0016] Further, the dielectric polarization converter 2 and the conical monopole antenna 5 are fixed by adding nylon columns to the extended outer ring.

[0017] The conical monopole antenna 5 of the antenna is fed by a coaxial line 6A, and the current is mainly distributed on the outside of the conical monopole antenna 5. Since the current is uniformly distributed along the same height, omnidirectional radiation mode can be realized in the microwave band; the Vivaldi antenna right ridge 3 and the Vivaldi antenna left ridge 4 are fed from the side by a coaxial line 7A, and energy is radiated along the opening direction of the Vivaldi antenna right ridge 3 and the Vivaldi antenna left ridge 4. The outer wall of the conical monopole antenna 5 can concentrate energy and reduce energy leakage on both sides of the antenna. Finally, when passing through the dielectric polarization converter 2, the linearly polarized wave is converted into a circularly polarized wave, and at the same time, the dielectric polarization converter can also concentrate energy, thereby improving the radiation gain of the Vivaldi antenna.

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

[0019] (1) The dual-band dual-polarization shared aperture antenna with pattern diversity provided by the present invention realizes a dual-band dual-polarization shared aperture design. The antenna is easy to process and can provide broadband bandwidths of 2.09-11.61 GHz (9.52 GHz, 138.9%) and 21.6-29.6 GHz (8 GHz, 31%). It can simultaneously cover the working bandwidths of multiple applications such as 4G LTE, the Sub-6GHz band in 5G, the n257 and n258 bands in the 5G millimeter wave band, WIFI, and UWB. It can adapt to various application scenarios and is a good candidate for multi-frequency communication systems.

[0020] (2) The present invention can realize pattern diversity design. The conical monopole antenna 5 can excite the omnidirectional radiation mode. The right ridge of the Vivaldi antenna and the left ridge of the Vivaldi antenna can cooperate with the dielectric polarization converter to realize the circular polarization radiation mode. The omnidirectional radiation has strong compatibility and can provide a wide range of wireless signal coverage. The circular polarization radiation mode can improve the communication quality due to its advantages in resisting polarization mismatch and multipath fading. Therefore, it has a very broad application prospect in 5G communication technology. At the same time, the conical monopole antenna and the dielectric polarization converter have a concentrating effect on the radiation waves of the Vivaldi antenna, which effectively improves the radiation gain of the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of a dual-frequency, dual-polarization, shared-aperture antenna unit with pattern diversity proposed in the present invention: Figure 1 (a) is a schematic diagram of the top view of the antenna unit; Figure 1 (b) is the xoz cross-sectional view of the antenna unit.

[0022] Figure 2 Schematic diagram of the antenna structure parameters.

[0023] Figure 3 The antenna reflection coefficient curve shows that the bandwidth of the antenna (return loss less than -10dB) is 2.09-11.61 GHz (9.52 GHz, 138.9%) and 21.6-29.6 GHz (8 GHz, 31%).

[0024] Figure 4 is the simulated gain pattern in the microwave band; Figure 4 (a) is the main polarization pattern of the antenna at phi = 0° at 2.4 GHz; Figure 4 (b) shows the main polarization and cross-polarization patterns of the antenna at theta = 90° at 2.4 GHz. Figure 4 (c) is the main polarization pattern of the antenna at phi = 0° at 6GHz; Figure 4 (d) in the figure is the main polarization and cross-polarization radiation pattern of the antenna at theta = 90° at 6GHz; Figure 4 (e) in the figure is the main polarization pattern of the antenna at phi=0° at 11GHz; Figure 4 (f) in the figure is the main polarization and cross-polarization radiation pattern of the antenna at theta = 90° at 11 GHz.

[0025] Figure 5 It is the millimeter wave band simulation gain pattern and axial ratio diagram; Figure 5 (a) is the axial ratio of the antenna in the millimeter wave band; Figure 5 (b) shows the main polarization and cross-polarization patterns of the antenna at phi = 0° at 25 GHz. Figure 5 (c) in the figure is the main polarization and cross-polarization radiation pattern of the antenna at phi = 90° at 25 GHz; Figure 5 (d) in the figure is the main polarization and cross-polarization radiation pattern of the antenna at phi = 0° at 29 GHz; Figure 5 (e) in the figure is the main polarization and cross-polarization radiation pattern of the antenna at phi=90° at 29 GHz.

[0026] In the figure: 1 metal floor, 2 dielectric polarization converter, 3 right ridge of Vivaldi antenna, 4 left ridge of Vivaldi antenna, 5 conical monopole antenna, 6 coaxial line A, 7 coaxial line B, 8 via A, 9 via B, 10 via C. DETAILED DESCRIPTION

[0027] The specific implementation scheme of the present invention is described in detail below in conjunction with the accompanying drawings and technical solutions.

[0028] refer to Figure 1 , providing a dual-band, dual-polarization, shared-aperture antenna with pattern diversity. The inner conductor of coaxial line 6A is welded to conical monopole antenna 5 through via 8A in metal floor 1, and the outer conductor of coaxial line 6A is welded to metal floor 1. The inner conductor of coaxial line 7B passes through the side wall of conical monopole antenna 5 through vias 9B and 10C and is welded to the left ridge 4 of the Vivaldi antenna. The outer conductor of coaxial line 7B is welded to the right ridge 3 of the Vivaldi antenna and the monopole antenna 5. The dielectric polarization converter 2 is placed directly above the conical monopole antenna. Vivaldi antennas 3 and 4, the conical monopole antenna, and the metal floor are all made of metal materials such as copper or aluminum.

[0029] The specific structural parameters of this embodiment correspond to the following positions: Figure 2As shown, L1 represents the length of the conical curved slot of the conical opening Vivaldi antenna; L2 represents the overall length of the right ridge 3 of the Vivaldi antenna and the left ridge 4 of the Vivaldi antenna; L3 represents the distance from the center of the side coaxial line B7 feeding the Vivaldi antenna to the bottom of the conical monopole antenna 5; W represents the side length of the square metal floor 1; W1 represents the diameter length of the dielectric polarization converter 2; W2 represents the thickness of the dielectric block in the dielectric polarization converter 2; W3 represents the thickness of the air layer between the dielectric blocks in the dielectric polarization converter 2; w1 represents the conical monopole antenna 5 represents the diameter of the extension ring; w2 represents the bottom diameter of the conical monopole antenna 5; w3 represents the distance between the trapezoidal connecting metal blocks of the right ridge 3 and the left ridge 4 of the Vivaldi antenna; S represents the opening width of the Vivaldi antenna conical slot at the top of the right ridge 3 and the left ridge 4 of the Vivaldi antenna; H1 represents the distance between the aperture surface of the conical monopole antenna 5 and the metal floor 1; H2 represents the height of the dielectric polarization converter 2; α represents the angle between the side wall of the conical monopole antenna 5 and the metal floor 1; the specific data are as follows:

[0030]

[0031] Figure 3 is the reflection coefficient simulated by the present invention. Figure 3 The antenna bandwidths are shown to be 2.09-11.61 GHz (9.52 GHz, 138.9%) and 21.6-29.6 GHz (8 GHz, 31%).

[0032] Figure 4 is the antenna radiation pattern in the microwave band. Figure 4 As can be seen in Figures (b), (d), and (f), the radiation pattern at Theta = 90° in the microwave band at 2.4 GHz, 6 GHz, and 11 GHz is essentially a perfect circle, achieving omnidirectional radiation. This shows that the antenna proposed in this invention has a stable radiation pattern in the microwave band.

[0033] Figure 5 is the antenna millimeter wave band radiation pattern and axial ratio diagram. Figure 5 (a) It can be seen that the antenna achieves an axial ratio of less than 3dB in the corresponding millimeter wave band and realizes circular polarization radiation. Figure 5 As can be seen from (b), (c), (d), and (e), the front-to-back ratios of the antenna in the phi = 0° and phi = 90° radiation patterns at 25 GHz and 29 GHz are both over 40 dB, and the gain is stable within the frequency band, achieving stable directional radiation.

[0034] The above examples are only for illustrating the technical concept and characteristics of the present application, only for specifically describing the present application, so that the person skilled in the art can understand the content of the present application and implement it, and cannot limit the protection scope of the present application. Any equivalent changes or modifications made according to the content of the present application should be covered within the protection scope of the present application.

Claims

1. A dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity, characterized in that: The dual-band dual-polarization shared aperture antenna includes a conical monopole metal radiator and its extended outer ring, left and right ridges of the Vivaldi antenna metal radiator, a dielectric polarization converter, a reflective floor, and two coaxial feed connections; the left and right ridge metal radiators of the Vivaldi antenna and the conical monopole radiator form a composite integrated structure; the conical monopole radiator is hollow inside, and there are two left and right ridge metal radiators of the Vivaldi antenna, both made of metal, which are symmetrically placed at the bottom of the conical monopole radiator.

2. The dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity according to claim 1, characterized in that: Specifically: The reflecting floor is a square metal floor (1), a hollow conical monopole metal radiator is provided above the metal floor (1), and a dielectric polarization converter (2) is placed directly above the conical monopole antenna (5); The square metal floor (1) is provided with a through hole A (8); The conical monopole metal radiator is a conical monopole antenna (5), and the top of the conical monopole antenna (5) is provided with an extended outer ring. The metal radiators of the Vivaldi antenna are specifically the right ridge (3) of the Vivaldi antenna and the left ridge (4) of the Vivaldi antenna; The coaxial feed connection comprises a coaxial line A (6) located directly below the conical monopole antenna (5) and a coaxial line B (7) on the side thereof; the coaxial line A (6) is welded and fixed to the conical monopole antenna (5) through a via hole A (8) on the metal floor (1); the coaxial line B (7) is connected to the left ridge (4) of the Vivaldi antenna through the via hole and is connected to the wall surface of the conical monopole antenna (5).

3. The dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity according to claim 2, characterized in that: The Vivaldi antenna right ridge (3) and the Vivaldi antenna left ridge (4) are a pair of metal blocks of special shape, both of which have the same thickness and are made of the same material as the conical monopole antenna, and a gap is left between the two.

4. The dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity according to claim 3, characterized in that: The Vivaldi antenna right ridge (3) and the Vivaldi antenna left ridge (4) are symmetrically placed at the bottom center of the conical radiator, and both are connected to the inner wall surface of the conical monopole antenna (5).

5. The dual-frequency dual-polarization shared aperture antenna with pattern diversity according to claim 3, characterized in that: The Vivaldi antenna right ridge (3), the Vivaldi antenna left ridge (4) and the conical monopole antenna (5) are manufactured by integrated 3D printing technology.

6. The dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity according to claim 2, characterized in that: The inner conductor of the coaxial line A (6) is welded to the conical monopole antenna (5) through the via A (8), and the outer conductor of the coaxial line A (6) is connected to the metal floor (1); the inner conductor of the coaxial line B (7) is connected to the left ridge (4) of the Vivaldi antenna through the via B (9) and the via C (10), and the outer conductor of the coaxial line B (7) is connected to the right ridge (3) of the Vivaldi antenna and the outer wall of the conical monopole antenna (5).

7. The dual-frequency dual-polarization shared aperture antenna with pattern diversity according to claim 2, characterized in that: The extended outer ring is a metal ring horizontally extended from the top edge of the conical monopole antenna (5), and the dielectric polarization converter (2) and the conical monopole antenna (5) are fixed by adding a nylon column to the extended outer ring.

8. The dual-frequency, dual-polarization, shared-aperture antenna with pattern diversity according to claim 2, characterized in that: A through hole A (8) is provided at the center of the metal floor (1); a through hole B (9) is provided on the outer wall of the conical monopole antenna (5); and a through hole C (10) is provided on the right ridge (3) of the Vivaldi antenna, and the through hole B (9) and the through hole C (10) are at the same horizontal position.

9. The dual-frequency dual-polarization shared aperture antenna with pattern diversity according to claim 1, characterized in that: The specific structure of the dielectric polarization converter (2) is that it is composed of a plurality of dielectric strips, and each dielectric strip forms an angle of 45° with the x-axis.

10. The dual-frequency dual-polarization shared aperture antenna with pattern diversity according to claim 9, characterized in that: The dielectric polarization converter is composed of a plurality of dielectric blocks of unequal lengths arranged in the same direction and at the same intervals. The linearly polarized waves emitted by the right ridge (3) and the left ridge (4) of the Vivaldi antenna are converted into circularly polarized waves by the dielectric polarization converter (2). At the same time, the side wall of the conical monopole antenna (5) and the dielectric polarization converter (2) can improve the gain of the Vivaldi antenna in the millimeter wave frequency band.

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