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

Abstract

The invention discloses a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation and control. A metasurface is sequentially provided with 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 in a holographic mode in the two-dimensional direction. A third dielectric layer is arranged below the metasurface, an air cavity exists between the third dielectric layer and the metasurface, a metal patch antenna in the feed structure is located on the upper surface of the third dielectric layer, and a metalized through hole is formed in the third dielectric layer; the reflection structure is a metal floor with a rectangle etched in the center and is located on the upper surface of the third dielectric layer; the air cavity, the metasurface, the feed structure and the reflection structure act together to form a Fabry-Perot resonant cavity antenna. According to the invention, the beam control flexibility is greatly improved.

Description

Technical Field

[0001] The invention relates to microwave communication technology, and in particular to a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation. Background Art

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

[0003] Holographic amplitude control is a technology that uses the principle of holography to accurately set the reflection or transmission coefficient of each unit of the metasurface, aiming to generate a preset 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 synthetic beam can be achieved. This method allows the radiation characteristics of the antenna to be changed quickly in a non-mechanical way, providing high flexibility and beam control capabilities. Applying this technology to beam control can significantly improve performance in communications, radar, and other wireless systems, ensuring optimal energy concentration and transmission efficiency in a specified direction.

[0004] T.Debogovic uses a phased array antenna as a radiation feed source and feeds it through a Wilkinson power divider network. By changing the phase difference between the two array element antennas, the antenna beam can be reconfigured with an angle range of -10° to 10°. There are two shortcomings in this antenna structure. First, the antenna beam deflection angle is small. Second, the antenna does not utilize the array element amplitude, but only uses the phase difference information between the array element antennas.

[0005] Currently, the beam pointing problem of the Fabry-Perot resonant cavity antenna mainly faces a problem, which is how to reasonably plan the transmission coefficient of the partially reflecting surface PRS in the Fabry-Perot resonant cavity antenna so that the Fabry-Perot resonant cavity antenna can obtain a large-angle beam deflection. Summary of the invention

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

[0007] The technical solution to achieve the purpose of the present invention is: a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation, comprising a metasurface, a feeding structure, a reflection structure and a support column, wherein:

[0008] The supersurface is composed of a five-layer structure, which is sequentially arranged with a first supersurface layer, a first dielectric layer, a second supersurface layer, a second dielectric layer, and a third supersurface layer; the first supersurface layer, the second supersurface layer, and the third supersurface layer are composed of supersurface units arranged holographically in a two-dimensional direction;

[0009] A third dielectric layer is arranged below the metasurface, and the feeding structure includes a metal patch antenna structure and a metallized through hole, the metal patch antenna is located on the upper surface of the third dielectric layer, and the metallized through hole is punched on the third dielectric layer; the reflective structure is a metal floor with a rectangular shape etched in the center, and is located on the upper surface of the third dielectric layer;

[0010] The supporting column is composed 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 works together with the metasurface, feeding structure, and reflective structure to form a Fabry-Perot resonant cavity antenna.

[0011] Furthermore, 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, and a rectangular metal ring patch and a third rectangular metal patch on the lower surface of the second dielectric layer.

[0012] Furthermore, 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.

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

[0014] Furthermore, according to the transmission amplitude of the Fabry-Perot resonant cavity antenna, the size of the metasurface unit is adjusted, and different transmission amplitudes are generated by adjusting units of different sizes for holographic arrangement, so as to realize large-angle beam deflection of the Fabry-Perot resonant cavity antenna. The specific method is as follows:

[0015] According to the phase of the target wave The phase of the reference wave Combination Calculate the transmission coefficient A of the metasurface unit at each position unit , A max The value range is [0.2,0.4], Amin 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, thereby obtaining a holographically distributed metasurface unit.

[0017] Furthermore, the metasurface units are composed of a 30*30 holographic distribution metasurface.

[0018] Furthermore, the third dielectric substrate is selected from Rogers RT5880.

[0019] Furthermore, the first dielectric substrate and the second dielectric substrate are made of FR4.

[0020] Compared with the prior art, the present invention has the following significant advantages: 1) By introducing the holographic amplitude control principle to carefully design the amplitude distribution of the metasurface unit, the flexibility of beam control is greatly improved. 2) By integrating the Fabry-Perot resonant cavity structure, the working efficiency of the antenna is enhanced, and its gain performance is also greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

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

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

[0024] Figure 4 is a flow chart of encoding of a super surface unit according to the present invention;

[0025] Figure 5 It is a simulation experiment result diagram of the S11 coefficient characteristic of the present invention;

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

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

[0028] The present invention adopts a metasurface structure as a radiator, adjusts the size of a partial reflection unit according to the transmission amplitude of a Fabry-Perot resonant cavity antenna, and arranges holographically different transmission amplitudes produced by adjusting units of different sizes, thereby realizing large-angle beam deflection of the Fabry-Perot resonant cavity antenna.

[0029] A Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation comprises a metasurface based on holographic amplitude type regulation, a feeding structure, a reflection structure and a supporting column.

[0030] The metasurface based on holographic amplitude type regulation is composed of a five-layer structure, including 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 arranged under the metasurface based on holographic amplitude type regulation, and an air cavity exists between the third dielectric layer and the metasurface.

[0031] The feeding structure is a metal patch antenna structure and a metallized through hole. The metal patch antenna is located on the upper surface of the third dielectric layer. The metallized through hole is punched on the third dielectric layer. The reflective structure is a metal floor with a rectangular center etched on it, which is located on the upper surface of the third dielectric layer.

[0032] As a preferred embodiment, 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, and a rectangular metal ring patch and a third rectangular metal patch on the lower surface of the second dielectric layer. Further 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] As a preferred embodiment, the metasurface unit is divided into a transmission type and a reflection type. The transmission coefficient of the transmission type metasurface is A max , the transmission coefficient of the reflective metasurface is A min , A max The general value is [0.2, 0.4], A min The general value is (0,0.1].

[0034] As a preferred implementation, the holographic arrangement is related to the phase of the target wave and the phase of the reference wave, specifically in the following manner:

[0035] First, according to the phase of the target wave The phase of the reference wave Combined with formula 1: Calculate the transmission coefficient A of the metasurface unit at each position unit, and then through CST simulation, the size of the metasurface unit is adjusted to change the transmission performance of the metasurface unit, thereby obtaining a holographically distributed metasurface unit.

[0036] As a preferred implementation, according to the operating frequency band of the Fabry-Perot resonant cavity antenna, the dielectric base substrate material of the patch antenna can be selected from RogersRT5880, etc., the dielectric substrate of the holographic amplitude-type control metasurface can be selected from FR4, etc., and the metal structure material can be selected from metals with good conductivity and stable properties, such as copper, aluminum, etc.

[0037] The technical principle of the present invention to realize the Fabry-Perot resonant cavity is as follows:

[0038] According to the holographic amplitude 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. By designing the array element size and making the array element amplitude satisfy Formula 1, an expected radiation beam can be obtained. This technical theory improves the beam angle control sensitivity of the Fabry-Perot resonant cavity and obtains large-angle beam reconfigurability.

[0039] Example

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

[0041] like Figures 1 to 3 As shown, an embodiment of the present invention provides a Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude type regulation, including a metasurface based on holographic amplitude type regulation, a feeding structure, a reflection structure and a support column. The metasurface based on holographic amplitude type regulation is composed of a five-layer structure, including a first metasurface layer, a first dielectric layer, a second metasurface layer, a second dielectric layer, and a third metasurface layer. The feeding structure includes a metal patch antenna structure and a metallized through hole, the metal patch antenna structure is located above the third dielectric layer, and the metallized through hole penetrates the third dielectric layer. The reflection structure is a metal floor with a central etched rectangle, which is located above the third dielectric layer.

[0042] like Figure 2 As shown in the figure, the holographic amplitude-type control metasurface changes the transmission performance of the metasurface unit by changing the side length of the square metal patches in the first metasurface layer and the second metasurface layer. The parameters are:

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

[0044] The side length of the first rectangular metal patch of the reflective metasurface unit structure is l2=4.8mm, and the side length of the second rectangular metal patch is l3=2.8mm; the side length of the first rectangular metal patch of the transmissive metasurface unit structure is l2=3.9mm, and the side length of the second rectangular metal patch is l3=3.9mm.

[0045] like Figure 3 As shown, the parameters of the patch antenna and reflective structure are:

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

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

[0048] The Fabry-Perot resonant cavity antenna based on holographic amplitude modulation in this embodiment operates at 12.7 GHz, and the operating frequency band is 12.6 GHz to 12.8 GHz. The feed layer dielectric substrate uses Rogers RT5880 with a thickness of 0.508 mm. The standard PCB processing technology is used to make the patch antenna and reflective copper layer of corresponding size on the upper surface of the dielectric substrate, and the metal floor is attached to the lower surface; the dielectric plate of the holographic amplitude modulation metasurface uses FR4 with a thickness of 3 mm. The standard PCB processing technology is used to make a 30×30 holographically distributed metal periodic array metasurface unit on the dielectric substrate, with a total size of 150×150 mm 2 , the metal structure thickness uses 18um copper.

[0049] The total height of the Fabry-Perot resonant cavity antenna structure based on holographic amplitude control in this embodiment is 21mm, of which the height of the air cavity between the patch antenna and the holographic amplitude modulation metasurface is 16.5mm. The Fabry-Perot resonant cavity antenna based on holographic amplitude control works well and improves the gain of the patch antenna at the frequency of 12.6GHz to 12.8GHz. When the directional pattern is 10°, the gain of the patch antenna is improved by 8.5dBi, and a reconfigurable antenna radiation pattern of -60° to 60° is generated by changing the coding state of the holographic amplitude control metasurface, and the gain variation range that can be achieved within the working frequency band is: 9.12dBi-15.15dBi.

[0050] Figure 4 The transmission coefficient A of the metasurface unit of the present invention is given as unit Schematic diagram of the determination process, according to the phase of the target wave The phase of the reference wave Combination Get the transmission coefficient A of the super surface unit at each position unit . Figure 5 to Figure 6 The relevant simulation results of the Fabry-Perot resonant cavity antenna based on holographic amplitude control are given. Figure 5 S is the S of the Fabry-Perot resonant cavity antenna based on holographic amplitude control in different coding modes. 11 ,The results show that the above antenna can work normally under the designed state; Figure 6 The directional patterns of the Fabry-Perot cavity antenna based on holographic amplitude control under different beam scanning states.

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

[0052] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0053] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control, characterized in that: It includes a metasurface, a feeding structure, a reflection structure and a supporting column, wherein: The supersurface is composed of a five-layer structure, which is sequentially arranged with a first supersurface layer, a first dielectric layer, a second supersurface layer, a second dielectric layer, and a third supersurface layer; the first supersurface layer, the second supersurface layer, and the third supersurface layer are composed of supersurface units arranged holographically in a two-dimensional direction; A third dielectric layer is arranged below the metasurface, and the feeding structure includes a metal patch antenna structure and a metallized through hole, the metal patch antenna is located on the upper surface of the third dielectric layer, and the metallized through hole is punched on the third dielectric layer; the reflective structure is a metal floor with a rectangular shape etched in the center, and is located on the upper surface of the third dielectric layer; The supporting column is composed 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 works together with the metasurface, feeding structure, and reflective structure to form a Fabry-Perot resonant cavity antenna.

2. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 1, characterized in that: 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.

3. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 1, characterized in that: 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.

4. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 1, characterized in that: The metasurface unit is divided into a transmission type and a reflection type. The transmission coefficient of the transmission type metasurface is different from the transmission coefficient of the reflection type metasurface. The transmission coefficient of the transmission type metasurface is greater than the transmission coefficient of the reflection type metasurface.

5. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 4 is characterized in that: According to the transmission amplitude of the Fabry-Perot resonant cavity antenna, the size of the metasurface unit is adjusted, and different transmission amplitudes are generated by adjusting units of different sizes for holographic arrangement, so as to realize the large-angle beam deflection of the Fabry-Perot resonant cavity antenna. The specific method is as follows: According to the phase of the target wave The phase of the reference wave Combination Calculate the transmission coefficient A of the metasurface unit at each position unit , A max The value range is [0.2,0.4], A min The value range is (0,0.1]; Through CST simulation, the size of the metasurface unit is adjusted to change the transmission performance of the metasurface unit, thereby obtaining a holographically distributed metasurface unit.

6. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 1, characterized in that: The metasurface units form a metasurface with a 30*30 holographic distribution.

7. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 1, characterized in that: The third dielectric substrate is Rogers RT5880.

8. The Fabry-Perot resonant cavity metasurface antenna based on holographic amplitude control according to claim 1, characterized in that: The first dielectric substrate and the second dielectric substrate are made of FR4.

Images