A Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation

Abstract

The application discloses a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation, and the metasurface sequentially comprises a first metasurface layer, a first dielectric layer, a second metasurface layer, a second dielectric layer and a third metasurface layer; the first metasurface layer, the second metasurface layer and the third metasurface layer are composed of holographic arrangement metasurface units in a two-dimensional direction; a third dielectric layer is arranged below the metasurface, and an air cavity exists between the metasurface and the third dielectric layer; a metal patch antenna in a feeding structure is located on the upper surface of the third dielectric layer, and a metalized through hole is punched on the third dielectric layer; a reflection structure is a metal floor with a rectangular center etching, and is located on the upper surface of the third dielectric layer; the air cavity, the metasurface, the feeding structure and the reflection structure jointly act to form the Fabry-Perot resonant cavity antenna. The application realizes a great improvement in beam control flexibility.

Description

TECHNICAL FIELD

[0001] The present application relates to microwave communication technology, and in particular to a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude regulation. BACKGROUND

[0002] Traditional beam steering antennas are usually large in size and have complex feed networks, while Fabry-Perot resonant cavity antennas can achieve high-gain beam steering with relatively simple structures. Fabry-Perot resonant cavity is a resonant structure composed of two parallel mirrors, widely used in optics and microwave fields to enhance the intensity of electromagnetic waves at specific frequencies. When integrated into metasurface antenna design, Fabry-Perot resonant cavity not only improves feed efficiency and gain, but also selectively amplifies certain frequency components through its resonant characteristics, optimizing signal transmission performance.

[0003] Holographic amplitude regulation is a technology that uses holographic principles to precisely set the reflection or transmission coefficients of each unit of the metasurface, aiming to generate a pre-set radiation pattern or beam pointing. By calculating the difference between the reference beam and the target beam, and adjusting the amplitude distribution of each metasurface unit accordingly, fine control of the synthesized beam can be achieved. This method allows rapid changes in antenna radiation characteristics in a non-mechanical way, providing high flexibility and beam steering capabilities. Applying this technology to beam steering can significantly improve performance in communication, radar and other wireless systems, ensuring optimal energy concentration and transmission efficiency in the specified direction.

[0004] T. Debogovic uses phased array antennas as radiation feed sources, fed through Wilkinson power division networks. By changing the phase difference between the two-element antennas, the antenna beam can be reconfigured, with an angle range of -10° to 10°. There are still two shortcomings in this antenna structure, first, the antenna beam deflection angle is small. Second, the antenna does not utilize the amplitude of the array elements, only using the phase difference information between the array elements.

[0005] Currently, the main problem of Fabry-Perot resonant cavity antenna beam pointing is how to reasonably plan the transmission coefficient of the partially reflective surface PRS in the Fabry-Perot resonant cavity antenna to make the Fabry-Perot resonant cavity antenna obtain large-angle beam deflection. SUMMARY

[0006] The purpose of the present application is to propose a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude regulation to solve the problem of large-angle beam deflection of the Fabry-Perot resonant cavity antenna.

[0007] The technical solution for achieving the object of the application is a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation, comprising a metasurface, a feed structure, a reflection structure and a support column, wherein:

[0008] The metasurface is composed of five layers of structures, sequentially arranged as a first metasurface layer, a first dielectric layer, a second metasurface layer, a second dielectric layer and a third metasurface layer; the first metasurface layer, the second metasurface layer and the third metasurface layer are composed of holographic arrangement of metasurface units in two-dimensional direction;

[0009] The third dielectric layer is arranged below the metasurface, the feed structure comprises a metal patch antenna structure and a metalized via, the metal patch antenna is located on the upper surface of the third dielectric layer, and the metalized via is punched on the third dielectric layer; the reflection structure is a metal floor with a rectangular center etched, located on the upper surface of the third dielectric layer;

[0010] The support column is composed of four nylon columns, the upper end of each nylon column is connected with the metasurface, the lower end of each nylon column is connected with the reflection structure, an air cavity is formed between the metasurface and the reflection structure, and the air cavity, the metasurface, the feed structure and the reflection structure jointly constitute the Fabry-Perot resonant cavity antenna.

[0011] Further, the metasurface unit is composed of a first rectangular metal patch on the upper surface of the first dielectric layer, a second rectangular metal patch on the lower surface of the first dielectric layer, a rectangular metal ring patch on the lower surface of the second dielectric layer and a third rectangular metal patch.

[0012] Further, the first rectangular metal patch, the second rectangular metal patch, the third rectangular metal patch and the rectangular metal ring patch are vertically aligned at the center.

[0013] Further, the metasurface unit is divided into a transmission type and a reflection type, the transmission coefficient of the transmission type metasurface and the transmission coefficient of the reflection type metasurface are different, and the transmission coefficient of the transmission type metasurface is greater than the transmission coefficient of the reflection type metasurface.

[0014] Further, the size of the metasurface unit is adjusted according to the transmission amplitude of the Fabry-Perot resonant cavity antenna, different transmission amplitudes are generated after adjustment by different sizes of units for holographic arrangement, and large-angle beam deflection of the Fabry-Perot resonant cavity antenna is realized, and the specific method is:

[0015] According to the phase of the target wave and the phase of the reference wave Combining Calculate the transmission coefficient A of the metasurface unit at each position unit , A max The value range of A is [0.2, 0.4]min The value range is (0, 0.1];

[0016] Through CST simulation, the size of the metasurface unit is adjusted to change the transmission performance of the metasurface unit, so that the holographic distribution metasurface unit is obtained.

[0017] Further, the metasurface unit is composed of a metasurface with a holographic distribution of 30*30.

[0018] Further, the third dielectric substrate is Rogers RT5880.

[0019] Further, the first dielectric substrate and the second dielectric substrate are FR4.

[0020] Compared with the prior art, the present application has the following advantages: 1) By introducing the holographic amplitude modulation principle, the amplitude distribution of the metasurface unit is carefully designed, and the flexibility of beam control is greatly improved. 2) By integrating the Fabry-Perot resonant cavity structure, not only the working efficiency of the antenna is enhanced, but also the gain performance is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a structural schematic diagram of the present application;

[0022] Figure 2 is a structural schematic diagram of the present application based on holographic amplitude modulation of the reflection and transmission metasurface unit;

[0023] Figure 3 is a schematic diagram of the reflection structure and the feeding structure of the present application;

[0024] Figure 4 is a flowchart of the present application for encoding the metasurface unit;

[0025] Figure 5 is a simulation experiment result graph of the S11 coefficient characteristics of the present application;

[0026] Figure 6 is a radiation direction simulation schematic diagram of the present application. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0028] This invention uses a metasurface structure as the radiator. Based on the transmission amplitude of the Fabry-Perot resonant cavity antenna, the size of some reflective elements is adjusted. By adjusting the size of the elements, different transmission amplitudes are generated and holographically arranged to achieve large-angle beam deflection of the Fabry-Perot resonant cavity antenna.

[0029] A Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation includes a metasurface based on holographic amplitude modulation, a feeding structure, a reflecting structure, and a support column.

[0030] The holographic amplitude-controlled metasurface consists of five layers: a first metasurface layer, a first dielectric layer, a second metasurface layer, a second dielectric layer, and a third metasurface layer. The first, second, and third metasurface layers are composed of metasurface units arranged holographically in a two-dimensional direction. A third dielectric layer is disposed beneath the holographic amplitude-controlled metasurface, with an air cavity existing between it and the metasurface.

[0031] The feeding structure consists of a metal patch antenna structure and metallized vias. The metal patch antenna is located on the upper surface of the third dielectric layer. The metallized vias are drilled into the third dielectric layer. The reflecting structure is a rectangular metal ground plane etched in the center, located on the upper surface of the third dielectric layer.

[0032] In a preferred embodiment, the metasurface unit comprises a first rectangular metal patch on the upper surface of the first dielectric layer, a second rectangular metal patch on the lower surface of the first dielectric layer, and a rectangular metal ring patch and a third rectangular metal patch on the lower surface of the second dielectric layer. More preferably, the centers of the first rectangular metal patch, the second rectangular metal patch, the third rectangular metal patch, and the rectangular metal ring patch are aligned vertically.

[0033] In one preferred embodiment, the metasurface unit is divided into transmissive and reflective types. The transmissive metasurface has a transmission coefficient of A. max The transmittance of the reflective metasurface is A. min A max The value is typically taken as [0.2, 0.4], A min The typical value is (0, 0.1).

[0034] In a preferred embodiment, the holographic arrangement is related to the phase of the target wave and the phase of the reference wave, specifically as follows:

[0035] First, based on the phase of the target wave Phase with reference wave Combining Formula 1: Calculate the transmission coefficient A of the metasurface element at each location. unitThen, the size of the metasurface unit is adjusted through CST simulation to change the transmission performance of the metasurface unit, so that the holographic distribution metasurface unit is obtained.

[0036] As a preferred embodiment, according to the operating frequency band of the Fabry-Perot resonant cavity antenna, the patch antenna dielectric substrate material can be selected from Rogers RT5880 and the like, the holographic amplitude type regulated metasurface dielectric substrate can be selected from FR4 and the like, and the metal structure material can be selected from metals with good conductivity and stable properties, such as copper, aluminum and the like.

[0037] The present application realizes the technical principle of the Fabry-Perot resonant cavity:

[0038] According to the holographic amplitude type theory, when the reference wave and the target wave interfere, the interference field intensity of different array elements can be obtained by recording the holographic interference pattern, and by designing the array element size, the array element amplitude meets formula 1, so that an expected radiation beam can be obtained. This technical theory improves the beam angle control sensitivity of the Fabry-Perot resonant cavity and obtains a large-angle beam reconfiguration.

[0039] Embodiment

[0040] In order to verify the effectiveness of the scheme of the present application, the following experimental design is carried out.

[0041] As Figures 1 to 3 shown, the present application provides a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation, which comprises a metasurface based on holographic amplitude type regulation, a feed structure, a reflection structure and a support column. The metasurface based on holographic amplitude type regulation is composed of five layers of structures, including a first metasurface layer, a first dielectric layer, a second metasurface layer, a second dielectric layer and a third metasurface layer. The feed structure comprises a metal patch antenna structure and a metallized via, the metal patch antenna structure is located above the third dielectric layer, and the metallized via penetrates the third dielectric layer. The reflection structure is a central etched rectangular metal floor, which is located above the third dielectric layer.

[0042] As Figure 2 shown, the holographic amplitude type regulated metasurface changes the transmission performance of the metasurface unit by changing the side length size of the square metal patch in the first metasurface layer and the second layer metasurface layer. Wherein each parameter is:

[0043] The period p of the metasurface unit is 5mm, the outer side length l1 of the rectangular metal ring patch is 4mm, the line width m1 of the rectangular metal ring patch is 0.4mm, and the gap distance n1 between the rectangular metal ring patch and the third rectangular metal patch is 0.5mm.

[0044] The side length of the first rectangular metal patch of the reflective metasurface unit structure is 4.8 mm, and the side length of the second rectangular metal patch is 2.8 mm; the side length of the first rectangular metal patch of the transmissive metasurface unit structure is 3.9 mm, and the side length of the second rectangular metal patch is 3.9 mm.

[0045] As shown in Figure 3 , the parameters of the patch antenna and the reflection structure are as follows:

[0046] The side length of the reflection structure is 150 mm, the length of the metal patch antenna is 9.3 mm, and the width of the metal patch antenna is 7.5 mm.

[0047] The thicknesses of the first dielectric layer and the second dielectric layer are 3 mm, the height of the air cavity is 16.5 mm, and the thickness of the third dielectric layer is 0.508 mm. The size of the entire antenna is finally 150 mm*150 mm.

[0048] The Fabry-Perot resonant cavity antenna based on holographic amplitude modulation works at 12.7 GHz, and the working frequency band is 12.6 GHz-12.8 GHz. The dielectric substrate of the feed layer is Rogers RT5880, with a thickness of 0.508 mm. The patch antenna and the reflection copper layer of corresponding size are made on the upper surface of the dielectric substrate by using the standard PCB processing technology, and the lower surface is attached with a metal ground plate. The dielectric plate of the holographic amplitude modulation metasurface is FR4, with a thickness of 3 mm. The 30*30 holographic distributed metal periodic array metasurface unit is made on the dielectric substrate by using the standard PCB processing technology, and the total size is 150*150 mm 2 , and the thickness of the metal structure is 18 um thick copper.

[0049] The total height of the Fabry-Perot resonant cavity antenna based on holographic amplitude modulation is 21 mm, wherein the height of the air cavity between the patch antenna and the holographic amplitude modulation metasurface is 16.5 mm. The Fabry-Perot resonant cavity antenna based on holographic amplitude modulation works well and improves the gain of the patch antenna at 12.6 GHz-12.8 GHz. When the directional diagram is 10°, the gain of the patch antenna is improved by 8.5 dBi. By changing the coding state of the holographic amplitude modulation metasurface, a reconfigurable antenna radiation directional diagram of-60°-60° is generated, and the gain change range in the working frequency band is 9.12 dBi-15.15 dBi.

[0050] Figure 4 The flowchart for determining the transmission coefficient A unit of the metasurface unit is given, and the phase of the target wave and the phase of the reference wave are combined Obtaining the transmission coefficient A of each position metasurface unit unit . Figures 5 to 6 The simulation results of the Fabry-Perot resonant cavity antenna based on holographic amplitude modulation are given. Figure 5 The S parameters of the Fabry-Perot resonant cavity antenna based on holographic amplitude modulation under different coding modes are given. 11 The results show that the above antenna can work normally under the designed state. Figure 6 The directional diagrams of the Fabry-Perot resonant cavity antenna based on holographic amplitude modulation under different beam scanning states are given.

[0051] In summary, by introducing the holographic amplitude modulation principle to carefully design the amplitude distribution of the metasurface antenna array, the beam control flexibility is greatly improved. In addition, by integrating the Fabry-Perot resonant cavity structure and the design of the transmission metasurface unit, not only the working efficiency of the antenna is enhanced, but also the gain performance is greatly improved.

[0052] The technical features of the above embodiments can be combined arbitrarily, and in order to make the description simple, not all possible combinations of the technical features in the above embodiments are described, however, as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the present application.

[0053] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation, characterized in that, It includes metasurfaces, feeding structures, reflective structures, and support pillars, among which: The metasurface consists of five layers, arranged sequentially as a first metasurface layer, a first dielectric layer, a second metasurface layer, a second dielectric layer, and a third metasurface layer; the first metasurface layer, the second metasurface layer, and the third metasurface layer are composed of metasurface units arranged holographically in a two-dimensional direction; A third dielectric layer is set below the metasurface. The feeding structure includes a metal patch antenna structure and a metallized via. The metal patch antenna is located on the upper surface of the third dielectric layer, and the metallized via is punched on the third dielectric layer. The reflective structure is a rectangular metal ground plane etched in the center, located on the upper surface of the third dielectric layer. The support column consists of four nylon columns. The upper end of each nylon column is connected to the metasurface, and the lower end of each nylon column is connected to the reflective structure. An air cavity is formed between the metasurface and the reflective structure. The air cavity, the metasurface, the feeding structure, and the reflective structure work together to form the Fabry-Perot resonant cavity antenna. The metasurface unit consists of a first rectangular metal patch on the upper surface of the first dielectric layer, a second rectangular metal patch on the lower surface of the first dielectric layer, and a rectangular metal ring patch and a third rectangular metal patch on the lower surface of the second dielectric layer; the first rectangular metal patch, the second rectangular metal patch, the third rectangular metal patch and the rectangular metal ring patch are aligned vertically.

2. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation according to claim 1, characterized in that, The metasurface units are divided into transmissive and reflective types. The transmission coefficient of the transmissive metasurface is different from that of the reflective metasurface, and the transmission coefficient of the transmissive metasurface is greater than that of the reflective metasurface.

3. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation according to claim 2, characterized in that, Based on the transmission amplitude of the Fabry-Perot resonant cavity antenna, the size of the metasurface elements is adjusted. By adjusting the element sizes, different transmission amplitudes are generated, and holographic arrangement is achieved to realize large-angle beam deflection of the Fabry-Perot resonant cavity antenna. The specific method is as follows: Based on the phase of the target wave Phase with reference wave , combined Calculate the transmission coefficient of the metasurface unit at each location. , The value range is [0.2, 0.4]. The value range is (0, 0.1]; By adjusting the size of the metasurface unit through CST simulation, the transmission performance of the metasurface unit can be changed, thereby obtaining a holographically distributed metasurface unit.

4. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation according to claim 1, characterized in that, The metasurface is composed of metasurface units arranged in a 30*30 holographic distribution.

5. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation according to claim 1, characterized in that, The third dielectric substrate was selected from Rogers RT5880.

6. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude modulation according to claim 1, characterized in that, The first and second dielectric substrates are selected from FR4.

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