Multi-mode polarized reconfigurable patch antenna

Abstract

The embodiment of the invention relates to the technical field of antennas, and provides a multi-mode polarization reconfigurable patch antenna, which comprises a radiation patch, a first dielectric substrate, a reflection floor, a slot structure floor, a second dielectric substrate, a first microstrip line feed structure and a second microstrip line feed structure, and is characterized in that the radiation patch is arranged on the upper surface of the first dielectric substrate; a second microstrip line feed structure is arranged on the surface of the second dielectric substrate; the second microstrip line feed structure is provided with two memristor switches, and the first microstrip line feed structure and the second microstrip line feed structure jointly form a 4-shaped feed network; the 4-shaped feed network of the patch antenna is compact in structure, a complex feed network structure is not needed, three radiation modes of left-hand circular polarization, right-hand circular polarization and linear polarization can be flexibly realized only by switching the conduction state of the memristor switch, and the adaptability and flexibility of the antenna in different communication scenes are enhanced.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a multi-mode polarization reconfigurable patch antenna. Background Art

[0002] In modern wireless communications and radar systems, different application scenarios have different requirements for the polarization characteristics of antennas, such as left-hand circular polarization, right-hand circular polarization, and linear polarization. Traditional multi-polarized antennas usually rely on complex feeding networks or mechanical rotating parts to achieve polarization switching. This design often leads to complex antenna structures, high costs, and difficulty in meeting the requirements of low profile and compact size in some applications. Therefore, it is of great significance to develop an antenna with a simple structure, flexible switching of polarization modes, and suitable for a variety of scenarios.

[0003] In existing antenna designs, the introduction of compact feed networks can effectively reduce the overall size, but it will also bring about a strong electromagnetic coupling effect, affecting the stability of antenna performance. In addition, to achieve multi-mode polarization switching, traditional designs require additional components such as complex power dividers or phase shifters, further increasing the complexity and cost of the design. How to optimize the feed network and reduce the electromagnetic coupling effect while maintaining a low profile and compact size is a technical difficulty in current antenna design.

[0004] Some current polarization reconfigurable antennas rely on mechanical rotation or complex electronic control modules to achieve polarization switching. At the same time, the loading of the reconfigurable control module often affects the radiation characteristics of the antenna. This type of design usually has problems such as low reliability and slow switching speed, and is difficult to apply in complex environments. At the same time, in order to achieve polarization switching, traditional antennas require high-precision processing technology and are difficult to manufacture. Therefore, developing an antenna solution that can achieve fast and reliable polarization switching through simple circuit control has become a research hotspot in the field of antenna technology. Summary of the invention

[0005] The embodiment of the present invention provides a multi-mode polarization reconfigurable patch antenna, which can realize fast switching of multi-mode polarization, and solves the shortcomings of the existing polarity and frequency reconfigurable antennas, such as complex antenna structure, large area occupied by the feeding network, complex reconfigurable control scheme, and the influence of DC bias on antenna performance during polarization switching.

[0006] A first aspect of an embodiment of the present invention provides a multi-mode polarization reconfigurable patch antenna, the patch antenna comprising a radiation patch (1), a first dielectric substrate (2), a reflection floor (3), a slot structure floor (4), and a second dielectric substrate (7) stacked in sequence from top to bottom;

[0007] The radiation patch (1) is arranged on the upper surface of the first dielectric substrate (2); the reflection floor (3) is arranged on the lower surface of the first dielectric substrate (2); the slot structure floor (4) is arranged on the upper surface of the second dielectric substrate (7);

[0008] A first microstrip line feeding structure (6) is provided on the slot structure floor (4); a second microstrip line feeding structure (8) is provided on the lower surface of the second dielectric substrate (7); and two memristor switches are provided on the second microstrip line feeding structure (8);

[0009] The patch antenna further comprises two feeding posts (5); the feeding posts (5) penetrate the first dielectric substrate (2), the second dielectric substrate (7), and the reflective floor (3), and are connected to the first microstrip line feeding structure (6), the second microstrip line feeding structure (8), and the radiation patch (1).

[0010] Furthermore, a first rectangular slot is provided in the -45 degree direction of the radiation patch (1), the first rectangular slot is located between the two feeding poles (5), and the length of the first rectangular slot is less than a quarter wavelength, so as to optimize the feeding path and maintain the circular polarization performance.

[0011] Furthermore, the edge of the radiation patch (1) is loaded with two second rectangular grooves, and the second rectangular grooves are used to provide impedance matching without affecting the circular polarization performance.

[0012] Furthermore, the slot structure floor (4) is loaded with a pentagonal slot, and the first microstrip line feeding structure (6) is arranged in the pentagonal slot;

[0013] Furthermore, the distance between the edge of the slot structure floor (4) and the edge of the first microstrip line feeding structure (6) is adjustable.

[0014] Furthermore, the first microstrip line feeding structure (6) comprises a first microstrip feed line, and the length of the first microstrip feed line is a quarter of a wavelength.

[0015] Furthermore, the second microstrip line feeding structure (8) comprises a second microstrip feed line, a first branch and a second branch, the first end of the second microstrip feed line is used to access an input signal, the second end is connected to the first branch and the second branch, the first branch and the second branch are of equal length, and the first branch and the second branch are connected to the two ends of the first microstrip line feeding structure (6) via the two feeding posts (5).

[0016] Furthermore, the extension direction of the second branch is the same as the extension direction of the second end of the second microstrip feeder, the extension direction of the first branch is 90 degrees to the extension direction of the second end of the second microstrip feeder, and the first microstrip line feeding structure (6), the second microstrip line feeding structure (8) and the two feeding poles (5) together form a compact 4-shaped feeding network.

[0017] Further, the two memristor switches include a first memristor switch and a second memristor switch, the first memristor switch is located on the first branch, and the second memristor switch is located on the second branch.

[0018] Further, when the first memristor switch is turned on and the second memristor switch is turned off, the patch antenna radiates left-hand circularly polarized electromagnetic waves;

[0019] When the first memristor switch is turned off and the second memristor switch is turned on, the patch antenna radiates right-hand circularly polarized electromagnetic waves;

[0020] When the first memristor switch is turned on and the second memristor switch is turned on, the patch antenna radiates linearly polarized electromagnetic waves.

[0021] Furthermore, the first memristor switch and the second memristor switch are molybdenum disulfide memristor switches, which adopt a silver / molybdenum disulfide / silver heterostructure and are composed of upper and lower silver electrodes sandwiching a MoS2 layer.

[0022] The embodiments of the present invention have the following beneficial effects:

[0023] 1. The patch antenna of the present invention loads a rectangular slot on the radiation patch, which optimizes the current path while maintaining the circular polarization performance of the antenna, increases the isolation between the two feeding points, avoids the complex structure of the stacked patches required by the traditional design, thereby reducing the overall cross-sectional height of the antenna and improving the practicality of the design.

[0024] 2. The first microstrip line feeding structure is loaded on the upper surface of the second dielectric substrate and is located in the pentagonal gap of the gap structure floor. The gap structure floor is not in direct contact with the first microstrip line feeding structure, but by adjusting the distance between the gap edge and the edge of the first microstrip feed line, the capacitance effect is used to achieve dynamic adjustment of the microstrip line impedance. The quarter-wavelength first microstrip feed line structure is between the radiation patch and the second microstrip line feeding structure. By changing its impedance, the impedance matching of the radiation patch impedance and the second microstrip line feeding structure can be achieved, so that it has the functions of both a phase shifter and an impedance matcher, thereby further optimizing the size and performance of the feeding network.

[0025] 3. The first microstrip feed line and the second microstrip feed line are printed on the upper and lower surfaces of the second dielectric substrate respectively and connected by a feeding column. This design reduces the electromagnetic coupling effect caused by the compact structure of the feeding network, while ensuring effective signal transmission, and further reduces the space occupied by the feeding network.

[0026] 4. Two memristor switches are loaded on the second microstrip line feeding structure, and the phase difference of the two output signals of the feeding network is controlled by the on and off of the memristor switch. More specifically, a molybdenum disulfide memristor switch with a silver / molybdenum disulfide / silver (Ag / MoS2 / Ag) heterostructure is used, which has the characteristic of "zero static power consumption". Its application can enable the reconfigurable structure to maintain a stable switching state without external voltage, thereby significantly reducing the static energy consumption of the system, providing a higher energy efficiency optimization space for the subsequent preparation of large-scale reconfigurable systems.

[0027] 5. The present invention controls the phase difference of the two output signals of the feeding network by turning on and off the memristor switch, generates three two-way output signals with equal amplitude and adjustable phase difference, feeds the signal into the feeding column, and feeds the radiating patch, so as to realize the rapid switching of multi-mode polarization. Since the antenna of the present invention does not directly load the memristor switch on the radiating patch, the performance effect of the bias circuit on the antenna can be reduced during polarization switching. The 4-shaped feeding network structure of the antenna is compact, and does not require a complex feeding network structure. Only by switching the conduction state of the memristor switch, the three radiation modes of left-hand circular polarization, right-hand circular polarization and linear polarization can be flexibly realized, which enhances the adaptability and flexibility of the antenna in different communication scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 is a three-dimensional diagram of a multi-mode polarization reconfigurable patch antenna according to an embodiment of the present invention;

[0030] Figure 2 A top view of the upper surface of a first dielectric substrate of a multi-mode polarization reconfigurable patch antenna according to an embodiment of the present invention;

[0031] Figure 3 A top view of the upper surface of the second dielectric substrate of the multi-mode polarization reconfigurable patch antenna in one embodiment of the present invention;

[0032] Figure 4A side view of a multi-mode polarization reconfigurable patch antenna according to an embodiment of the present invention;

[0033] Figure 5 A top view of the lower surface of the second dielectric substrate of the multi-mode polarization reconfigurable patch antenna in one embodiment of the present invention;

[0034] Figure 6 are the impedance bandwidth simulation results of three polarization states of the multi-mode polarization reconfigurable patch antenna in one embodiment of the present invention;

[0035] Figure 7 Simulation results of axial ratio bandwidth of three polarization states of a multi-mode polarization reconfigurable patch antenna in one embodiment of the present invention;

[0036] Figure 8 is a simulation result of linear polarization state gain of a multi-mode polarization reconfigurable patch antenna in one embodiment of the present invention;

[0037] FIG9 is a simulation result of circular polarization gain of a multi-mode polarization reconfigurable patch antenna in two polarization states according to an embodiment of the present invention: FIG9(a) is a left-hand circular polarization state; FIG9(b) is a right-hand circular polarization state;

[0038] Figure 10 is the simulation results of the E-plane and H-plane radiation patterns of the multi-mode polarization reconfigurable patch antenna in two polarization states at 4 GHz in one embodiment of the present invention: Figure 10 (a) E-plane in left-hand circular polarization state; Figure 10 (b) H-plane in left-hand circular polarization state; Figure 10 (c) E-plane in right-hand circular polarization state; Figure 10 (d) H-plane in right-hand circular polarization state; Figure 10 (e) E-plane in linear polarization state; Figure 10 (f) H-plane in linear polarization state. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in 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. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0040] The terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices.

[0041] Reference to "embodiments" in the present invention means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described in the present invention may be combined with other embodiments.

[0042] The present invention aims to solve the technical problems of the existing polarity and frequency reconfigurable antennas, such as complex structure, large area occupied by the feeding network, complex reconfigurable control scheme, and adverse effects of DC bias on antenna performance during polarization switching, and proposes a multi-mode polarization reconfigurable patch antenna. The present invention controls the phase difference of the two output signals of the feeding network by turning on and off the memristor switch, and generates three two-way output signals with equal amplitude and adjustable phase difference, thereby realizing rapid switching of multi-mode polarization.

[0043] In the antenna design of a specific embodiment of the present invention, the memristor switch is not directly loaded on the radiating patch, thereby effectively reducing the influence of the bias circuit on the antenna performance during the polarization switching process. The antenna adopts a compact 4-shaped feeding structure, does not require a complex feeding network design, and can achieve three radiation modes of left-hand circular polarization, right-hand circular polarization and linear polarization by simply controlling the conduction state of the memristor switch, significantly improving the adaptability and flexibility of the antenna in different communication scenarios.

[0044] In order to enable those skilled in the art to better understand the present invention, the present invention is described in detail below in conjunction with specific embodiments.

[0045] Reference Figure 1 , an embodiment of the present invention provides a multi-mode polarization reconfigurable patch antenna, the structure of which includes a radiation patch 1, a first dielectric substrate 2, a reflection floor 3, a slot structure floor 4, and a second dielectric substrate 7 stacked in sequence from top to bottom;

[0046] The radiation patch 1 is arranged on the upper surface of the first dielectric substrate 2; the reflection floor 3 is arranged on the lower surface of the first dielectric substrate 2; the slot structure floor (4) is arranged on the upper surface of the second dielectric substrate (7);

[0047] A first microstrip line feeding structure 6 is provided on the slot structure floor 4; a second microstrip line feeding structure 8 is provided on the lower surface of the second dielectric substrate 7; and two memristor switches are provided on the second microstrip line feeding structure 8;

[0048] The patch antenna also includes two feeding posts; the feeding posts pass through the first dielectric substrate 2, the second dielectric substrate 7, and the reflective floor 3, and are connected to the first microstrip line feeding structure 6, the second microstrip line feeding structure 8 and the radiation patch 1.

[0049] The resonant frequency of the patch antenna is determined by the geometric dimensions, the characteristics of the dielectric substrate and the loading structure. The resonant frequency calculation formula of the patch antenna is:

[0050]

[0051] Where f is the resonant frequency, c is the speed of light, ε r is the dielectric constant, L eff is the effective length of the patch antenna.

[0052] In a specific embodiment, the radiation patch 1 is a rectangular structure. Taking the radiation patch as an example, the effective length L of the antenna can be determined according to the formula: eff =l1=24mm.

[0053] Please refer to Figure 3 The slot structure floor 4 is loaded with a pentagonal slot, and the first microstrip line feeding structure 6 is arranged in the pentagonal slot; the distance between the edge of the slot structure floor 4 and the edge of the first microstrip line feeding structure 6 is adjustable. The first microstrip line feeding structure 6 includes a first microstrip feed line, and the length of the first microstrip feed line is a quarter wavelength.

[0054] The phase difference of the first microstrip line feeding structure 6 is achieved by adjusting the length of the first microstrip feed line. The phase delay of the signal propagating in the first microstrip feed line can be calculated by the following formula:

[0055]

[0056] where ε eff is the effective dielectric constant of the first microstrip feed line, which depends on the characteristics and geometric dimensions of the dielectric substrate. l is the length of the first microstrip feed line. λ0 is the free space wavelength of the signal. In order to achieve a phase difference of 90°, the effective electrical length of the first microstrip feed line should be one quarter of the signal wavelength. The first microstrip line feeding structure 6 adopts a zigzag design to simplify simulation and layout. The specific structural parameters are defined as w1=2.378mm, w2=2.686mm, l9=7.36mm.

[0057] In a specific embodiment, reference Figure 4 The first dielectric substrate 2 and the second dielectric substrate 7 are both made of NY9220 plate, with a thickness h1 of 0.8 mm, a dielectric constant of 2.2, and a dielectric loss tangent of 0.0009; an air layer is provided between the first dielectric substrate (2) and the second dielectric substrate (7), and the air layer height h2 is 0.8 mm.

[0058] In order to reduce the size of the antenna, the present invention designs a compact 4-shaped feeding network. Figure 5 The second microstrip line feeding structure 8 includes a second microstrip feed line, a first branch and a second branch. The first end of the second microstrip feed line is used to access the input signal, and the second end is connected to the first branch and the second branch. The lengths of the first branch and the second branch are equal. The first branch and the second branch are connected to the two ends of the first microstrip line feeding structure 6 through the two feeding columns.

[0059] In a specific embodiment, the extension direction of the second branch is the same as the extension direction of the second end of the second microstrip feed line, that is, Figure 1 The positive y-axis direction in the coordinate system shown (xoy plane is parallel to the patch antenna) is defined as the 90-degree direction of the lower surface of the second dielectric substrate 7, and the extension direction of the first branch is the 180-degree direction of the lower surface of the second dielectric substrate 7, that is, the negative x-axis direction. The first microstrip line feeding structure 6, the second microstrip line feeding structure 8 and the two feeding posts together form a compact 4-shaped feeding network. It should be noted that the definition of the above coordinate system is only for describing the positional relationship of the various structures of the patch antenna, and cannot be understood as a limitation on the positional relationship of the present invention.

[0060] Due to the compact geometric layout of the figure-4 feed network, the quarter-wavelength phase shifter may be affected by electromagnetic coupling effects, which mainly manifests as capacitive coupling between adjacent microstrip lines. The coupled signal will introduce additional current, thus affecting the phase delay function of the phase shifter. The relevant formula for the capacitive effect and the coupling coefficient is:

[0061]

[0062] For the capacitance effect formula, C is the capacitance between two conductor microstrip lines, d is the distance between adjacent conductors, and A is the overlapping area of ​​adjacent conductors. By arranging the feeding structure on the upper and lower surfaces of the second dielectric substrate 7, the distance between the conductors is increased, the coupling capacitance C is reduced, and the capacitive coupling effect is reduced.

[0063] For the coupling coefficient formula, k is the coupling coefficient, which indicates the coupling strength between the two conductor microstrip lines, M is the mutual inductance, which indicates the field coupling between the two conductor microstrip lines, and L1 and L2 are the self-inductances of the two conductor microstrip lines. In the present invention, the first microstrip line feeding structure 6 and the second microstrip line feeding structure 8 are respectively arranged on the upper and lower surfaces of the second dielectric substrate 7, and the relative positions between the current paths are no longer parallel and are isolated by the dielectric substrate. This design changes the distribution of the magnetic field, reduces the mutual inductance M, thereby reducing the coupling effect of the magnetic field and reducing the area of ​​the feeding network.

[0064] The first microstrip line feeding structure 6 is arranged in the pentagonal gap of the gap structure floor 4, and there is no direct contact between the gap structure floor and the first microstrip line feeding structure 6. The characteristic impedance calculation formula of the first microstrip line feeding structure 6 is:

[0065]

[0066] Where Z0 is impedance, L is inductance, and C is capacitance. From the capacitance effect formula, it can be concluded that the distance between the edge of the floor and the edge of the first microstrip feeder determines the capacitance of the first microstrip feeder. By adjusting the distance between the edge of the gap and the edge of the first microstrip feeder, the characteristic impedance Z0 of the first microstrip line feeding structure 6 can be effectively changed without changing the feeding structure and the width of the first microstrip feeder structure.

[0067] By adjusting the impedance of the first microstrip line feeding structure 6, the impedance of the radiation patch can be matched with the impedance of the second microstrip line feeding structure 8. This design enables it to have the functions of both a phase shifter and an impedance matcher, thereby further optimizing the size and performance of the feeding network.

[0068] Therefore, the pentagonal gap geometric structure dimensions of the gap structure floor 4 are determined to be l8=10.5 mm and l7=3.5 mm.

[0069] The two feeding posts 5 are copper posts, the copper post connected to the first branch is defined as the first copper post; the copper post connected to the second branch is defined as the second copper post, and its diameter R1 = r3 = 0.24 mm. The reflective floor 3 is provided with a through hole with a diameter of R2 = 0.6 mm at each position where the two feeding posts pass through, to prevent the feeding posts 5 from contacting the reflective floor 3 made of metal.

[0070] The second microstrip line feeding structure 8 has a microstrip line length l12=17.3mm, l10=19.68mm, and a second microstrip feed line width w4=2.378mm, corresponding to a 50 ohm impedance at a 4 GHz operating frequency. The memristor switch length w5=1mm, and the branch width w3=2.378mm.

[0071] In order to further optimize the impedance bandwidth and make the 4-shaped feeding structure more compact, a one-eighth wavelength impedance transformer is loaded on the second microstrip feed line to achieve impedance gradient matching. Compared with the classic quarter-wavelength transformer, the design of the one-eighth wavelength transformer is more compact. The impedance transformer achieves transition matching by gradually converting the load impedance to the source impedance, and its geometric size is l11 = 5.1 mm.

[0072] Two MoS2 memristor switches are loaded on the second microstrip line feeding structure, and the phase difference of the two output signals of the feeding network is controlled by turning on and off the MoS2 memristor switches. The MoS2 switch uses a silver / molybdenum disulfide / silver (Ag / MoS2 / Ag) heterostructure and has the characteristic of "zero static power consumption". Its application enables the reconfigurable structure to maintain a stable switching state without external voltage, thereby significantly reducing the static energy consumption of the system, providing a higher energy efficiency optimization space for the subsequent preparation of large-scale reconfigurable systems.

[0073] Taking left-hand circular polarization as an example, when the memristor switch SW1 is turned on and SW2 is turned off, the current path in the 4-shaped feeding network is: the input signal is transmitted through the second microstrip line feeding structure 8 via the memristor switch SW1, and the first copper column feeds the first port of the first microstrip line feeding structure 6. At the same time, after the input signal passes through SW1, it is transmitted to port 2 through the first microstrip line feeding structure 6 with an effective electrical length of one quarter of a wavelength. At this time, the signal at port 2 has a phase delay of 90° compared to port 1, and the amplitudes of the signals at the two ports are the same, thereby forming a left-hand circular polarization wave.

[0074] That is, when the first memristor switch is turned on and the second memristor switch is turned off, the patch antenna radiates left-hand circularly polarized electromagnetic waves;

[0075] When the first memristor switch is turned off and the second memristor switch is turned on, the patch antenna radiates right-hand circularly polarized electromagnetic waves;

[0076] When the first memristor switch is turned on and the second memristor switch is turned on, the patch antenna radiates linearly polarized electromagnetic waves.

[0077] Due to the compact design of the 4-shaped feeding network, the first microstrip line feeding structure 6 achieves an effective electrical length of one quarter wavelength through a zigzag design. However, since the geometric distance between port 1 and port 2 on the patch surface is less than one quarter wavelength, the input signal will be conducted to the other port through the patch surface, resulting in failure of the phase shifter function. To solve this problem, please refer to Figure 2 , a rectangular slot is loaded at -45 degrees of the radiation patch 1 to optimize the feeding path and maintain the circular polarization performance, and its loading position is located between the two feeding posts. l2 = 6.5 mm, l3 = 0.6 mm.

[0078] Two rectangular slots are loaded on the edge of the radiation patch 1, and their positions are selected to achieve impedance matching without affecting the circular polarization performance. The size of the rectangular slot is defined as l4 = l5 = 1 mm.

[0079] Figure 6The impedance bandwidth simulation results of the three polarization states of the antenna are shown in Figure 2. The impedance bandwidths of the two polarization states are basically overlapping. The impedance bandwidth of the left-hand state is 3.92-4.03 GHz, the impedance bandwidth of the right-hand state is 3.93-4.05 GHz, and the linear polarization impedance bandwidth is 3.93-4.04 GHz.

[0080] Figure 7 The following are the simulation results of the axial ratio bandwidth of the antenna in two circular polarization states. In the left-hand working state, the axial ratio of the antenna in the range of 3.981-4.002GHz is kept below 3dB; in the right-hand working state, the axial ratio of the antenna in the range of 3.986-4.006GHz is also kept below 3dB.

[0081] Figure 8 This is the simulation result of the antenna linear polarization gain. It can be seen that the maximum gain of the antenna can reach 7.8 GHz at 4 GHz, and the antenna performance is good.

[0082] FIG9 shows the simulation results of circular polarization gain of the antenna in two polarization states. It can be seen that the maximum gain of the antenna can reach 7.8 GHz at the target frequency, and the antenna performance is good.

[0083] Figure 10 shows the simulation results of the E-plane and H-plane radiation patterns of the antenna in three polarization states at 4 GHz. It can be observed that when the antenna is in left-hand circular polarization mode, along the z-axis direction, the left-hand circular polarization gain of the antenna is more than 40 dB higher than the right-hand circular polarization gain, indicating that the antenna has higher polarization purity and lower cross-polarization component, that is, the left-hand circular polarization mode of the antenna has excellent circular polarization performance.

[0084] When the antenna is in right-hand circular polarization mode, along the z-axis direction, the left-hand circular polarization gain of the antenna is more than 30db higher than the right-hand circular polarization gain, indicating that the antenna has higher polarization purity and lower cross-polarization component, that is, the right-hand circular polarization mode of the antenna has excellent circular polarization performance.

[0085] The embodiments of the present invention are described in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A multi-mode polarization reconfigurable patch antenna, characterized in that: The patch antenna comprises a radiation patch (1), a first dielectric substrate (2), a reflection floor (3), a slot structure floor (4), and a second dielectric substrate (7) which are stacked in sequence from top to bottom; The radiation patch (1) is arranged on the upper surface of the first dielectric substrate (2); The reflective floor (3) is provided on the lower surface of the first dielectric substrate (2); the slot structure floor (4) is provided on the upper surface of the second dielectric substrate (7); A first microstrip line feeding structure (6) is provided on the slot structure floor (4); a second microstrip line feeding structure (8) is provided on the lower surface of the second dielectric substrate (7); and two memristor switches are provided on the second microstrip line feeding structure (8); The patch antenna further comprises two feeding posts (5); the feeding posts (5) penetrate the first dielectric substrate (2), the second dielectric substrate (7), and the reflective floor (3), and are connected to the first microstrip line feeding structure (6), the second microstrip line feeding structure (8), and the radiation patch (1).

2. The multi-mode polarization reconfigurable patch antenna according to claim 1, characterized in that: The radiation patch (1) is provided with a first rectangular slot, the first rectangular slot is located between the two feeding posts (5), the length of the first rectangular slot is less than a quarter wavelength, and is used to optimize the feeding path and maintain circular polarization performance.

3. The multi-mode polarization reconfigurable patch antenna according to claim 2, characterized in that: The edge of the radiation patch (1) is loaded with two second rectangular grooves, wherein the second rectangular grooves are used to provide impedance matching without affecting circular polarization performance.

4. The multi-mode polarization reconfigurable patch antenna according to claim 3, characterized in that: The slot structure floor (4) is loaded with a pentagonal slot, and the first microstrip line feeding structure (6) is arranged in the pentagonal slot; The slot structure floor (4) does not contact the first microstrip line feeding structure (6), and the distance between the edge of the slot structure floor (4) and the edge of the first microstrip line feeding structure (6) is adjustable.

5. The multi-mode polarization reconfigurable patch antenna according to claim 4, characterized in that: The first microstrip line feeding structure (6) comprises a first microstrip feed line, and the length of the first microstrip feed line is a quarter of a wavelength.

6. The multi-mode polarization reconfigurable patch antenna according to claim 5, characterized in that: The second microstrip line feeding structure (8) comprises a second microstrip feed line, a first branch and a second branch, the first end of the second microstrip feed line is used to access an input signal, the second end is connected to the first branch and the second branch, the first branch and the second branch are of equal length, and the first branch and the second branch are connected to two ends of the first microstrip line feeding structure (6) via two feeding posts (5).

7. The multi-mode polarization reconfigurable patch antenna according to claim 6, characterized in that: The extension direction of the second branch is the same as the extension direction of the second end of the second microstrip feeder, the extension direction of the first branch is 90 degrees to the extension direction of the second end of the second microstrip feeder, and the first microstrip line feeding structure (6), the second microstrip line feeding structure (8) and the two feeding posts (5) together form a compact 4-shaped feeding network.

8. The multi-mode polarization reconfigurable patch antenna according to claim 7, characterized in that: The two memristor switches include a first memristor switch and a second memristor switch, wherein the first memristor switch is located on the first branch node, and the second memristor switch is located on the second branch node.

9. The multi-mode polarization reconfigurable patch antenna according to claim 8, characterized in that: When the first memristor switch is turned on and the second memristor switch is turned off, the patch antenna radiates left-hand circularly polarized electromagnetic waves; When the first memristor switch is turned off and the second memristor switch is turned on, the patch antenna radiates right-hand circularly polarized electromagnetic waves; When the first memristor switch is turned on and the second memristor switch is turned on, the patch antenna radiates linearly polarized electromagnetic waves.

10. The multi-mode polarization reconfigurable patch antenna according to claim 9, characterized in that: The first memristor switch and the second memristor switch are molybdenum disulfide memristor switches, which adopt a silver / molybdenum disulfide / silver heterostructure and are composed of upper and lower silver electrodes sandwiching a MoS2 layer.

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