A multi-mode polarization reconfigurable patch antenna

Abstract

Embodiments of the present invention relate to the field of antenna technology, and provide a multi-mode polarization reconfigurable patch antenna. The antenna includes: a radiation patch, a first dielectric substrate, a reflection floor, a slot structure floor, a second dielectric substrate, a first microstrip line feeding structure, and a second microstrip line feeding structure. The radiation patch is disposed on the upper surface of the first dielectric substrate; the second microstrip line feeding structure is provided on the surface of the second dielectric substrate; two memristor switches are provided on the second microstrip line feeding structure, and the first microstrip line feeding structure and the second microstrip line feeding structure jointly form a 4-shaped feeding network; the 4-shaped feeding network of this patch antenna is compact, without a complex feeding network structure, and only by switching the conduction state of the memristor switches, three radiation modes of left-handed circular polarization, right-handed circular polarization, and linear polarization can be flexibly realized, enhancing the adaptability and flexibility of the antenna in different communication scenarios.

Description

Technical Field

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

[0002] In modern wireless communication and radar systems, different application scenarios have different requirements for the polarization characteristics of antennas, such as left-handed circular polarization, right-handed circular polarization, and linear polarization. Traditional multi-polarization antennas usually rely on complex feeding networks or mechanical rotating components to achieve polarization switching. Such a design often results in a complex antenna structure, high cost, 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 polarization mode switching, and applicable to multiple scenarios.

[0003] In the existing antenna design, although the introduction of a compact feeding network can effectively reduce the overall size, it will also bring a strong electromagnetic coupling effect, affecting the stability of the 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 design complexity and cost. How to optimize the feeding 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 mostly 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 has an impact on the radiation characteristics of the antenna. Such designs usually have problems of low reliability and slow switching speed, and are difficult to be applied in complex environments. At the same time, to achieve polarization switching, traditional antennas require high-precision processing technology, and the manufacturing difficulty is relatively high. Therefore, developing an antenna solution that can achieve fast and reliable polarization switching through simple circuit control has become a research hotspot in the technical field of antennas. Summary of the Invention

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

[0006] The first aspect of the embodiments of the present invention provides a multi-mode polarization reconfigurable patch antenna, where the patch antenna 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;

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

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

[0009] The patch antenna further includes two feeding posts (5); the feeding posts (5) penetrate through the first dielectric substrate (2), the second dielectric substrate (7), and the reflection 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] Further, 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 posts (5), and the length of the first rectangular slot is less than one-quarter wavelength, which is used to optimize the feeding path and maintain the circular polarization performance.

[0011] Further, two second rectangular slots are loaded on the edge of the radiation patch (1), and the second rectangular slots are used to provide impedance matching and do not affect the circular polarization performance.

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

[0013] Further, 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] Further, the first microstrip line feeding structure (6) includes a first microstrip feeder, and the length of the first microstrip feeder is one-quarter wavelength.

[0015] Further, the second microstrip line feeding structure (8) includes a second microstrip feeder, a first branch, and a second branch. The first end of the second microstrip feeder is used to access the input signal, 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, and the first branch and the second branch are connected to both ends of the first microstrip line feeding structure (6) through the two feeding posts (5).

[0016] Further, the extending direction of the second stub is the same as that of the second end of the second microstrip feeder, the extending direction of the first stub is perpendicular to that 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 figure-of-four 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 stub, and the second memristor switch is located on the second stub.

[0018] Further, when the first memristor switch is turned on and the second memristor switch is turned off, the patch antenna radiates left-handed 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-handed 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] Further, 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 a MoS2 layer clamped by upper and lower silver electrodes.

[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 radiating patch. While maintaining the circular polarization performance of the antenna, it optimizes the current path, increases the isolation between the two feeding points, and avoids the complex structure of stacked patches required by traditional designs, thereby reducing the overall profile 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 slot of the slot structure floor. The slot structure floor does not directly contact the first microstrip line feeding structure, but by adjusting the distance between the slot edge and the edge of the first microstrip feeder, the dynamic adjustment of the microstrip line impedance is realized by using the capacitance effect. This quarter-wavelength first microstrip feeding structure is between the radiating patch and the second microstrip line feeding structure. By changing its impedance, the impedance matching between the radiating patch impedance and the second microstrip line feeding structure impedance can be achieved, enabling 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.

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

[0026] 4. Two memristor switches are loaded on the second microstrip line feeding structure to control the phase difference between the two output signals of the feeding network through the on / off states of the memristor switches. More specifically, a molybdenum disulfide memristor switch with a silver / molybdenum disulfide / silver (Ag / MoS2 / Ag) heterostructure is adopted, which has the characteristic of "zero static power consumption". Its application enables the reconfigurable structure to maintain a stable switch state under the condition of no external voltage, thus significantly reducing the static power consumption of the system and providing a higher space for optimizing the energy efficiency for the subsequent preparation of large-scale reconfigurable systems.

[0027] 5. In the present invention, the phase difference between the two output signals of the feeding network is controlled through the on / off states of the memristor switches to generate two output signals with three adjustable phase differences of equal amplitude. The signals are fed into the feeding post and used to feed the radiating patch, thereby realizing the rapid switching of multi-mode polarization. Since the memristor switches in the antenna of the present invention are not directly loaded on the radiating patch, the influence of the bias circuit on the performance of the antenna can be reduced during polarization switching. The 4-shaped feeding network structure of this antenna is compact and does not require a complex feeding network structure. Only by switching the conduction states of the memristor switches, three radiation modes of left-handed circular polarization, right-handed circular polarization, and linear polarization can be flexibly realized, enhancing the adaptability and flexibility of the antenna in different communication scenarios. Description of the Drawings

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 It is a three-dimensional view of a multi-mode polarization reconfigurable patch antenna in an embodiment of the present invention;

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

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

[0032] Figure 4Side view of the multi-mode polarization reconfigurable patch antenna in an embodiment of the present invention;

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

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

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

[0036] Figure 8 Simulated results of the gain in the linear polarization state of the multi-mode polarization reconfigurable patch antenna in an embodiment of the present invention;

[0037] Figure 9 shows the simulated results of the circular polarization gain in two polarization states of the multi-mode polarization reconfigurable patch antenna in an embodiment of the present invention: Figure 9(a) Left-handed circular polarization state; Figure 9(b) Right-handed circular polarization state;

[0038] Figure 10 shows the simulated results of the E-plane and H-plane patterns in two polarization states of the multi-mode polarization reconfigurable patch antenna at 4 GHz in an embodiment of the present invention: Figure 10(a) E-plane in the left-handed circular polarization state; Figure 10(b) H-plane in the left-handed circular polarization state; Figure 10(c) E-plane in the right-handed circular polarization state; Figure 10(d) H-plane in the right-handed circular polarization state; Figure 10(e) E-plane in the linear polarization state; Figure 10(f) H-plane in the linear polarization state. Detailed implementation manners

[0039] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0040] The terms "first", "second", etc. in the specification and claims of the present invention and the above accompanying drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. 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 optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0041] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments can be included in at least one embodiment of the invention. The phrase occurring in various places in the specification is not necessarily referring to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive of other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described in the present invention can be combined with other embodiments.

[0042] In view of the technical problems of the existing polarization and frequency reconfigurable antennas, such as complex structure, large occupied area of the feeding network, complex reconfigurable control scheme, and adverse effects of DC bias on antenna performance during polarization switching, the present invention proposes a multi-mode polarization reconfigurable patch antenna. By controlling the phase difference between the two output signals of the feeding network through the on-off of the memristor switches, the present invention generates two output signals with equal amplitude and adjustable phase difference, so as to realize the rapid switching of multi-mode polarization.

[0043] In the antenna design of a specific embodiment of the present invention, the memristor switches are not directly loaded on the radiation patch, thus effectively reducing the influence of the bias circuit on the antenna performance during the polarization switching process. This antenna adopts a compact quadrilateral feeding structure, without the need for complex feeding network design. By only controlling the conduction state of the memristor switches, three radiation modes of left-handed circular polarization, right-handed circular polarization, and linear polarization can be realized, 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 will be described in detail below in conjunction with specific embodiments.

[0045] Referring to 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 provided 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] The slot structure floor 4 is provided with a first microstrip line feeding structure 6; the second microstrip line feeding structure 8 is provided on the lower surface of the second dielectric substrate 7; two memristor switches are provided on the second microstrip line feeding structure 8;

[0048] The patch antenna further includes two feeding posts; the feeding posts penetrate through the first dielectric substrate 2, the second dielectric substrate 7, and the reflection 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 jointly determined by the geometric dimensions, the characteristics of the dielectric substrate, and the loading structure. The calculation formula for the resonant frequency of the patch antenna is as follows:

[0050] ;

[0051] where f is the resonant frequency, c is the speed of light, is the dielectric constant, is the effective length of the patch antenna.

[0052] In a specific embodiment, the radiation patch 1 is of a rectangular structure. Taking the radiation patch being set to resonate at 4 GHz as an example, the effective length of the antenna can be determined according to the formula =l1 = 24 mm.

[0053] Please refer to Figure 3 , a pentagonal slot is loaded in the slot structure floor 4, 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 feeder, and the length of the first microstrip feeder 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 feeder. The phase delay of the signal propagating in the first microstrip feeder can be calculated by the following formula:

[0055] ;

[0056] where is the effective dielectric constant of the first microstrip feeder, which depends on the characteristics and geometric dimensions of the dielectric substrate. l is the length of the first microstrip feeder. 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 feeder should be a quarter of the signal wavelength. The first microstrip line feeding structure 6 adopts a zigzag design to simplify the simulation and layout, and the specific structure parameters are defined as w1 = 2.378 mm, w2 = 2.686 mm, l9 = 7.36 mm.

[0057] In a specific embodiment, referring to Figure 4 , both the first dielectric substrate 2 and the second dielectric substrate 7 adopt NY9220 plates, the thickness h1 of both is 0.8 mm, the dielectric constant is 2.2, and the tangent of the dielectric loss angle is 0.0009; an air layer is provided between the first dielectric substrate (2) and the second dielectric substrate (7), and the height h2 of the air layer is 0.8 mm.

[0058] To reduce the size of the antenna, the present invention designs a compact four-shaped feeding network. Please refer to Figure 5 , the second microstrip line feeding structure 8 includes a second microstrip feeder, a first branch and a second branch. The first end of the second microstrip feeder is used to access the input signal, 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, and the first branch and the second branch are connected to both ends of the first microstrip line feeding structure 6 through the two feeding posts.

[0059] In a specific embodiment, the extending direction of the second branch is the same as the extending direction of the second end of the second microstrip feeder, that is, Figure 1 in the coordinate system shown (the xoy plane is parallel to the patch antenna), the positive y-axis direction is defined as the 90-degree direction of the lower surface of the second dielectric substrate 7, and the extending 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 four-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 should not be construed as a limitation on the positional relationship of the present invention.

[0060] Due to the compact geometric layout of the four-shaped feeding network, the quarter-wavelength phase shifter may be affected by the electromagnetic coupling effect, which is mainly manifested as the capacitive coupling between adjacent microstrip lines. The coupling signal will introduce additional current, thus affecting the phase delay function of the phase shifter. The relevant formulas for the capacitance effect and the coupling coefficient are:

[0061] ;

[0062] ;

[0063] 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 respectively arranging the feeding structures on the upper and lower surfaces of the second dielectric substrate 7, the distance between conductors is increased, the coupling capacitance C is reduced, and the capacitive coupling effect is reduced.

[0064] For the coupling coefficient formula, k is the coupling coefficient, representing the coupling strength between two conductor microstrip lines, M is the mutual inductance, representing the magnetic field coupling between two conductor microstrip lines, and

[0065] The first microstrip line feeding structure 6 is disposed in the pentagonal slit of the slit structure floor 4, and there is no direct contact between the slit structure floor and the first microstrip line feeding structure 6. The characteristic impedance calculation formula of the first microstrip line feeding structure 6 is:

[0066]

[0067] where is the impedance, L is the inductance, and C is the capacitance. It can be obtained from the capacitance effect formula 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 slit and the edge of the first microstrip feeder, the characteristic impedance 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. .

[0068] By adjusting the impedance of the first microstrip line feeding structure 6, impedance matching between the radiation patch impedance and the second microstrip line feeding structure 8 can be achieved. This design enables it to have both the functions of a phase shifter and an impedance matcher, thereby further optimizing the size and performance of the feeding network.

[0069] Therefore, the geometric structure dimensions of the pentagonal slit of the slit structure floor 4 are determined as l8 = 10.5 mm and l7 = 3.5 mm.

[0070] 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 their diameters R1 = r3 = 0.24 mm. The reflection floor 3 is provided with a through hole with a diameter R2 = 0.6 mm at each position passing through the 2 feeding posts to prevent the feeding posts 5 from contacting the metal reflection floor 3.

[0071] The microstrip line lengths of the second microstrip line feeding structure 8 are l12 = 17.3 mm and l10 = 19.68 mm, the width of the second microstrip feeder is w4 = 2.378 mm, corresponding to a 50-ohm impedance at a working frequency of 4 GHz. The length of the memristor switch is w5 = 1 mm, and the width of the branch is w3 = 2.378 mm.

[0072] In order to further optimize the impedance bandwidth and make the 4-shaped feeding structure more compact, an eighth-wavelength impedance transformer is loaded on the second microstrip feeder to achieve gradual impedance matching. Compared with the classic quarter-wavelength transformer, the design of the eighth-wavelength transformer is more compact. This impedance transformer realizes transitional matching by gradually converting the load impedance to the source impedance, and its geometric dimension l11 = 5.1 mm.

[0073] Two molybdenum disulfide memristor switches are loaded on the second microstrip line feeding structure, and the phase difference between the two output signals of the feeding network is controlled by the on-off of the molybdenum disulfide memristor switches. The molybdenum disulfide switch adopts a silver / molybdenum disulfide / silver (Ag / MoS2 / Ag) heterostructure, which has the characteristic of "zero static power consumption". Its application enables the reconfigurable structure to maintain a stable switch state under the condition of no external voltage, thus significantly reducing the static energy consumption of the system and providing a higher energy efficiency optimization space for the subsequent preparation of large-scale reconfigurable systems.

[0074] Taking left-handed circular polarization as an example, when the memristor switch SW1 is on and SW2 is off, the current path in the figure-eight feeding network is as follows: The input signal is transmitted through the memristor switch SW1 via the second microstrip line feeding structure 8 and fed to port one of the first microstrip line feeding structure 6 by the first copper post. At the same time, after passing through SW1, the input signal is transmitted to port two through the first microstrip line feeding structure 6 with an effective electrical length of a quarter wavelength. At this time, the signal at port two has a 90° phase delay compared to port one, and the signal amplitudes at both ports are the same, thus forming a left-handed circularly polarized wave.

[0075] That is, when the first memristor switch is on and the second memristor switch is off, the patch antenna radiates left-handed circularly polarized electromagnetic waves;

[0076] When the first memristor switch is off and the second memristor switch is on, the patch antenna radiates right-handed circularly polarized electromagnetic waves;

[0077] When the first memristor switch is on and the second memristor switch is on, the patch antenna radiates linearly polarized electromagnetic waves.

[0078] Due to the compact design of the figure-eight feeding network, the first microstrip line feeding structure 6 realizes an effective electrical length of a quarter wavelength through a zigzag design. However, since the geometric distance between the two ports on the patch surface is less than a quarter wavelength, the input signal will be conducted to the other port through the patch surface, resulting in the failure of the phase shifter function. To solve this problem, please refer to Figure 2 , a rectangular slot is loaded in the -45-degree direction of the radiating patch 1 to optimize the feeding path and maintain the circular polarization performance, and its loading position is between the two feeding posts. l2 = 6.5mm, l3 = 0.6mm.

[0079] Two rectangular slots are loaded on the edge of the radiating patch 1, and their positions need to be selected to complete impedance matching without affecting the circular polarization performance. The dimensions of the rectangular slots are defined as l4 = l5 = 1mm.

[0080] Figure 6The simulation results of the impedance bandwidth for three polarization states of the antenna are presented. The impedance bandwidths of two polarization states are basically coincident. Among them, the impedance bandwidth in the left-handed state is 3.92 - 4.03 GHz, the impedance bandwidth in the right-handed state is 3.93 - 4.05 GHz, and the impedance bandwidth in the linear polarization state is 3.93 - 4.04 GHz.

[0081] Figure 7 The simulation results of the axial ratio bandwidth for two circular polarization states of the antenna are shown. In the left-handed operating state, the axial ratio of the antenna remains below 3 dB in the range of 3.981 - 4.002 GHz; while in the right-handed operating state, the axial ratio of the antenna also remains below 3 dB in the range of 3.986 - 4.006 GHz.

[0082] Figure 8 The simulation results of the linear polarization gain of the antenna are presented. It can be seen that the maximum gain of the antenna can reach 7.8 dBi at 4 GHz, indicating good antenna performance.

[0083] Figure 9 shows the simulation results of the circular polarization gain for two polarization states of the antenna. It can be seen that the maximum gain of the antenna can reach 7.8 dBi at the target frequencies, indicating good antenna performance.

[0084] Figure 10 shows the simulation results of the E-plane and H-plane radiation patterns for three polarization states of the antenna at 4 GHz. It can be observed that when the antenna is in the left-handed circular polarization mode, along the z-axis direction, the left-handed circular polarization gain of the antenna is more than 40 dB higher than the right-handed circular polarization gain, indicating that the antenna has high polarization purity and low cross-polarization components, that is, the left-handed circular polarization mode of this antenna has excellent circular polarization performance.

[0085] When the antenna is in the right-handed circular polarization mode, along the z-axis direction, the left-handed circular polarization gain of the antenna is more than 30 dB higher than the right-handed circular polarization gain, indicating that the antenna has high polarization purity and low cross-polarization components, that is, the right-handed circular polarization mode of this antenna has excellent circular polarization performance.

[0086] The embodiments of the present invention have been described in detail above. Specific examples are used in this article to illustrate the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A multi-mode polarization reconfigurable patch antenna, characterized in that, The patch antenna 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; The radiation patch (1) is disposed on the upper surface of the first dielectric substrate (2); The reflection floor (3) is provided on the lower surface of the first dielectric substrate (2); the slot structure floor (4) is disposed on the upper surface of the second dielectric substrate (7); An air layer is provided between the first dielectric substrate (2) and the second dielectric substrate (7); A first microstrip line feeding structure (6) is provided on the slot structure floor (4). A pentagonal slot is loaded in the slot structure floor (4). The first microstrip line feeding structure (6) is disposed within the pentagonal slot, and the slot structure floor (4) does not contact the first microstrip line feeding structure (6); the first microstrip line feeding structure (6) includes a first microstrip feeder; A second microstrip line feeding structure (8) is provided on the lower surface of the second dielectric substrate (7); the second microstrip line feeding structure (8) includes a second microstrip feeder, a first branch, and a second branch. The first end of the second microstrip feeder is used to access an input signal, and the second end is connected to the first branch and the second branch. The first branch and the second branch have equal lengths. The first branch and the second branch are connected to both ends of the first microstrip line feeding structure (6) through two feeding posts (5); two memristor switches are provided on the second microstrip line feeding structure (8); 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; The patch antenna further includes two feeding posts (5); the feeding posts (5) penetrate through the first dielectric substrate (2), the second dielectric substrate (7), and the reflection 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 A first rectangular slot is provided on the radiation patch (1). 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 the circular polarization performance.

3. The multi-mode polarization reconfigurable patch antenna according to claim 2, wherein Two second rectangular slots are loaded on the edge of the radiation patch (1). The second rectangular slots are used to provide impedance matching and do not affect the circular polarization performance.

4. The multi-mode polarization reconfigurable patch antenna according to claim 3, wherein 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 length of the first microstrip feeder is a quarter wavelength.

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

7. The multi-mode polarization reconfigurable patch antenna according to claim 6, wherein The height of the air layer is 0.8 mm.

8. The multi-mode polarization reconfigurable patch antenna according to claim 7, characterized in that, An impedance transformer is loaded on the second microstrip feeder, and the length is an eighth wavelength.

9. The multi-mode polarization reconfigurable patch antenna according to claim 8, wherein When the first memristor switch is turned on and the second memristor switch is turned off, the patch antenna radiates left-handed 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-handed 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, adopting a silver / molybdenum disulfide / silver heterostructure, which is composed of an MoS2 layer clamped by upper and lower silver electrodes.

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