A single-layer broadband polarization reconfigurable antenna

Abstract

The present invention relates to a single-layer wide-band polarization reconfigurable antenna, belonging to the field of communication, comprising a dielectric substrate, a microstrip radiation patch composed of two mutually perpendicular metal units is arranged on the top of the dielectric substrate, each metal unit is provided with a feeding port, a metal grounding plate is arranged at the bottom of the dielectric substrate; a slit is opened on the metal grounding plate; the metal unit is used as a feeding transmission line, and by adjusting the length of the metal unit, when a single port is fed, coupling is generated between the two metal units, and the metal grounding plate interacts with the metal grounding plate to excite a left-handed circularly polarized wave or a right-handed circularly polarized wave, and when two ports are fed simultaneously, the left-handed circularly polarized wave and the right-handed circularly polarized wave are superimposed to synthesize a linearly polarized wave. The present invention realizes the reconstruction of three polarization modes by adopting two mutually perpendicular metal units as microstrip feed lines and opening a slit on the metal grounding plate, and has the characteristics of wide frequency band, simple structure and high utilization rate.

Description

Technical Field

[0001] The invention relates to the field of communication technology, and in particular to a single-layer wide-band polarization reconfigurable antenna. Background Art

[0002] With the rapid development of international mobile communications, 5G / 6G commercial deployment is gradually being carried out around the world, and C-band spectrum resources are becoming increasingly scarce; however, traditional antennas are difficult to cover multiple frequency bands, and a single polarization mode cannot achieve frequency reuse and effectively solve the channel congestion problem. Under the same size conditions, reconfigurable antennas can achieve the reconstruction of one or more parameters such as operating frequency, radiation direction, and polarization mode by changing their structure, thereby having the functions of multiple antennas, reducing equipment duplication, and reducing installation costs and volume.

[0003] At present, there are three common methods to achieve polarization reconfiguration: the first is to load RF switches, the second is to add matching networks, and the third is to change the mechanical structure. Although the first method achieves polarization reconfiguration, it introduces too many switches, resulting in a larger volume. The second method has a complex overall structure, and the design and production process is cumbersome. The third method has a complex process, high production cost, and difficulty in integration. In addition, the existing polarization reconfigurable antennas still have the problem of insufficient bandwidth under different polarization conditions. Summary of the invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a single-layer broadband polarization reconfigurable antenna to solve the shortcomings of the prior art.

[0005] The object of the present invention is achieved by the following technical scheme: a single-layer wide-band polarization reconfigurable antenna, which includes a dielectric substrate, a microstrip radiation patch composed of two mutually perpendicular metal units is arranged on the top of the dielectric substrate, each metal unit is provided with a feeding port, and a metal grounding plate is arranged at the bottom of the dielectric substrate; a gap is opened on the metal grounding plate;

[0006] Two metal units are used as feeding transmission lines. By adjusting the length of the two metal units, when a single port is fed, coupling occurs between the two metal units, and they interact with the slotted metal ground plate to excite left-handed circularly polarized waves or right-handed circularly polarized waves. When the two ports are fed simultaneously, the left-handed circularly polarized wave and the right-handed circularly polarized wave are superimposed to synthesize a linearly polarized wave.

[0007] Furthermore, the shape of the gap opened on the metal grounding plate is circular.

[0008] Furthermore, a circular convex section is added to the circular gap, and the antenna axial ratio is reduced by the circular convex section.

[0009] Furthermore, a metal strip is added in the circular gap to increase the antenna bandwidth.

[0010] Furthermore, a circular metal structure is provided on one side of the metal strip, and the antenna reflection coefficient is reduced by the circular metal structure.

[0011] The present invention has the following advantages: a single-layer wide-band polarization reconfigurable antenna, which realizes reconstruction of three polarization modes by adopting two mutually perpendicular 50-ohm metal units as microstrip feed lines and making slits on the metal ground plate. The effective working frequency band capacity of the antenna under three polarization conditions reaches 2.26GHz (4.16GHz-6.42GHz), has a wide frequency band, a simple structure, a high utilization rate, and can effectively reduce the repeatability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A top view of the present invention;

[0013] Figure 2 A bottom view of the present invention;

[0014] Figure 3 This is the reflection coefficient result diagram of the antenna;

[0015] Figure 4 is the antenna axial ratio result diagram;

[0016] Figure 5 A schematic diagram of a gain simulation result of feeding the first feeding port;

[0017] Figure 6 A schematic diagram of a gain simulation result of feeding the second feeding port;

[0018] Figure 7 This is a schematic diagram comparing the gain simulation results of the antenna under different feeding conditions.

[0019] In the figure: 1-dielectric substrate, 2-metal unit, 3-metal ground plate, 4-circular convex section, 5-metal strip, 6-circular metal structure, 7-first feeding port, 8-second feeding port. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the detailed description of the embodiments of the present application provided below in conjunction with the drawings is not intended to limit the scope of protection of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. The present invention is further described below in conjunction with the drawings.

[0021] like Figure 1 and Figure 2 As shown, the present invention specifically relates to a single-layer wide-band polarization reconfigurable antenna, which consists of three parts: a dielectric substrate 1, a microstrip radiation patch and a metal ground plate 3, and the feeding method is microstrip line feeding; the dielectric substrate 1 adopts a FR4 epoxy resin board with a thickness of 0.8 mm, and the microstrip radiation patch is located on the top of the dielectric substrate 1. It consists of two mutually perpendicular metal units 2, each of which is provided with a feeding port, and a circular gap is opened on the metal ground plate 3, and the characteristic impedance is equal to 50 ohms.

[0022] To further optimize the circular polarization characteristics, a circular convex section 4 is added on the basis of the circular gap opened in the metal ground plate 3 to significantly reduce the axial ratio of the antenna. Its 3dB axial ratio bandwidth is 4.1GHz-6.2GHz, the impedance bandwidth is 4.7GHz-6.8GHz, and the actual operating frequency band of the antenna is 4.7GHz-6.2GHz.

[0023] In order to further expand the effective working bandwidth, a metal strip 5 is added in the circular gap opened in the antenna metal ground plate 3, so that the 3dB axial ratio bandwidth band of the antenna is 3.8GHz-6.5GHz, the impedance bandwidth band is 4.2GHz-6.3GHz, the effective working frequency band of the antenna is 4.2GHz-6.3GHz, and the actual bandwidth is increased from 1.5GHz to 2.1GHz.

[0024] Furthermore, a circular metal structure 6 is provided on one side of the metal strip 5, and the circular metal structure 6 further reduces the antenna reflection coefficient, so that the reflection coefficient at the center resonant frequency is less than -15dB (specifically, the frequency band is 4.8GHz-5.6GHz), thereby optimizing the performance. At the same time, the impedance bandwidth is expanded, and the effective working frequency band is expanded from 2.1GHz to 2.26GHz.

[0025] The present invention uses two metal units 2 as feeding transmission lines. By adjusting the lengths of the two 50-ohm metal units 2, when a single port is fed, coupling is generated between the two metal units 2, and the two metal units 2 interact with the slotted metal ground plate 3 to excite left-handed circularly polarized waves or right-handed circularly polarized waves. When two ports are fed simultaneously, the left-handed circularly polarized waves and the right-handed circularly polarized waves are superimposed to synthesize linearly polarized waves, thereby realizing three polarization characteristics.

[0026] When the first feeding port 7 is fed and the second feeding port 8 is connected to a matching load, the reflection coefficient and axial ratio of the antenna are as follows: Figure 3 and Figure 4 As shown, where S11 is the reflection coefficient; Figure 3 As shown in the figure, the antenna resonant frequency is 5.2GHz and the impedance bandwidth is 42.7% (4.16GHz-6.42GHz). Figure 4 As shown, when only the first feeding port 7 is fed, the 3dB axial ratio bandwidth of the antenna is 50.9% (3.84GHz-6.46GHz), and the effective working bandwidth is equal to the impedance bandwidth. When only the second feeding port 8 is fed, the 3dB axial ratio bandwidth of the antenna is 50.3% (3.84GHz-6.42GHz), and the effective working bandwidth is equal to the impedance bandwidth, and the effective working frequency bands of the two are consistent. When the first feeding port 7 and the second feeding port 8 are fed at the same time, the effective working bandwidth of the antenna is equal to the impedance bandwidth, and the axial ratio in the entire working frequency band is greater than 40dB, indicating that the linear polarization purity of the antenna is very high.

[0027] Taking the polarization at 5 GHz as an example, the circular polarization characteristics are further explained. Figure 5 It can be seen from FIG. 1 that when only the first feeding port 7 is fed, the antenna generates left-hand circularly polarized electromagnetic waves in the +z-axis direction; Figure 6 It can be seen that when only the second feeding port 8 is fed, the antenna generates right-hand circularly polarized electromagnetic waves in the +z-axis direction, and the two have opposite rotation directions.

[0028] like Figure 7 As shown, when the first feeding port 7 and the second feeding port 8 are fed separately, that is, the antenna works in left-hand circular polarization and right-hand circular polarization modes respectively, and the gain in the working frequency band is maintained between 3.2-4.2dB. When the first feeding port 7 and the second feeding port 8 are fed simultaneously, that is, the antenna works in linear polarization mode, after the frequency rises to 4GHz, the gain is significantly greater than the circular polarization mode.

[0029] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used for various other combinations, modifications and improvements, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not deviate from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A single-layer broadband polarization reconfigurable antenna, characterized in that: It comprises a dielectric substrate (1), a microstrip radiation patch composed of two mutually perpendicular metal units (2) is arranged on the top of the dielectric substrate (1), each metal unit (2) is provided with a feeding port, and a metal grounding plate (3) is arranged at the bottom of the dielectric substrate (1); a gap is opened on the metal grounding plate (3); The two metal units (2) serve as a feeding transmission line. By adjusting the length of the two metal units (2), when a single port is fed, coupling is generated between the two metal units (2), and the two metal units (2) interact with the slotted metal ground plate (3) to excite a left-hand circularly polarized wave or a right-hand circularly polarized wave. When the two ports are fed simultaneously, the left-hand circularly polarized wave and the right-hand circularly polarized wave are superimposed to synthesize a linearly polarized wave. The shape of the slit opened on the metal grounding plate (3) is circular; A circular convex section (4) is added to the circular gap, and the axial ratio of the antenna is reduced by the circular convex section (4); A metal strip (5) is added in the circular gap to increase the bandwidth of the antenna; A circular metal structure (6) is provided on one side of the metal strip (5), and the circular metal structure (6) is used to reduce the antenna reflection coefficient.

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