A broadband OAM mode and polarization composite reconfigurable array antenna

Abstract

The present invention relates to the field of antenna technology, and discloses a broadband OAM mode and polarization composite reconfigurable array antenna, comprising a dielectric substrate and four unit antennas, a metal grounding layer is provided on the upper surface of the dielectric substrate, the four unit antennas on the metal grounding layer form a 2×2 array, a cross-shaped coupling slot is engraved on the metal grounding layer, a microstrip line layer is provided on the lower surface of the dielectric substrate, a DC bias circuit is provided on the microstrip line layer, and the dielectric substrate is connected to a reconfigurable balanced feeding mechanism through the microstrip line layer, and the reconfigurable balanced feeding mechanism is used to feed the unit antennas. The array antenna has two different polarization characteristics: X-line polarization and Y-line polarization, and three different OAM mode vortex electromagnetic waves can be realized for each polarization state.

Description

Technical Field

[0001] The invention relates to a broadband OAM mode and polarization composite reconfigurable array antenna, belonging to the technical field of antennas. Technical Background

[0002] The rapid development of wireless communication technology has put forward higher requirements on system requirements and working modes. Traditional single-function antennas cannot meet current needs well and have become a bottleneck restricting the development of system performance. The proposal and development of reconfigurable antennas provide a good solution to these problems. Polarization reconfigurable antennas can increase the capacity of the system through frequency reuse and solve the problem of polarization mismatch in communication, thereby improving the communication quality. At the same time, based on the orthogonality between OAM modes, the use of OAM multi-mode multiplexing transmission can increase channel capacity, reduce system complexity and improve energy efficiency.

[0003] Since modern PCB technology and metal 3D printing technology are very mature, the processing accuracy is also very guaranteed in the not very high frequency band. At the same time, the processed products can have the characteristics of low profile, small volume and high integration, which is conducive to the large-scale production and application of antennas. Therefore, the OAM mode and polarization composite reconfigurable magneto-electric dipole array antenna using a combination of single-layer PCB technology and metal 3D printing technology has very practical significance in terms of broadband, high gain and cost reduction. Summary of the invention

[0004] 1. Purpose of the invention

[0005] In order to overcome the shortcomings of the prior art, the present invention provides a broadband OAM mode and polarization composite reconfigurable array antenna. The array antenna can switch between two linear polarization states. At the same time, for each polarization state, three different OAM modes (-1, 0, +1 orders) of vortex electromagnetic waves can be generated, thereby realizing independent reconstruction of OAM mode and polarization, and has the advantages of stable gain, wide bandwidth, simple structure, etc.

[0006] (II) Technical solution

[0007] To achieve the above object, the technical solution adopted by the present invention is: a broadband OAM mode and polarization composite reconfigurable array antenna, comprising a dielectric substrate and four unit antennas, wherein a metal grounding layer is provided on the upper surface of the dielectric substrate, and the four unit antennas are arranged on the metal grounding layer to form a 2×2 array antenna, and a cross-shaped coupling slot is engraved on the metal grounding layer;

[0008] Preferably: a microstrip line layer is provided on the lower surface of the dielectric substrate, a DC bias circuit is also provided on the microstrip line layer, the dielectric substrate is connected to a reconfigurable balanced feeding mechanism through the microstrip line layer, the reconfigurable balanced feeding mechanism is used to feed the unit antenna and simultaneously control different excitation directions applied to the unit antenna, thereby generating different polarization states, namely X-line polarization and Y-line polarization, and different initial phases.

[0009] Preferably: the microstrip line layer includes two broadband 90° adjustable phase shifters, two time delays, one one-to-four equal amplitude and equal phase power distributor, four one-to-two equal amplitude and equal phase power distributors, and twelve DC bias circuits. The four unit antennas are all provided with a reconfigurable balanced feeding mechanism for exciting the cross-type coupling slot. The input ends of two of the one-to-two equal amplitude and equal phase power distributors are respectively connected to the broadband 90° adjustable phase shifters, and the broadband 90° adjustable phase shifters are connected to the output end of the one-to-four equal amplitude and equal phase power distributor. The input ends of the other two one-to-two equal amplitude and equal phase power distributors are respectively connected to the time delays, and the time delays are connected to the output end of the one-to-four equal amplitude and equal phase power distributor.

[0010] Preferably, the output branches of the one-to-two equal-amplitude and equal-phase power divider are respectively fed to the feeding port corresponding to each unit antenna, so that the excitation phases of the feeding ports corresponding to each unit antenna remain consistent.

[0011] Preferably: the unit antenna is composed of four metal magnetic electric dipoles, and the metal magnetic electric dipoles serve as radiators, the four metal magnetic electric dipoles are equidistantly arranged and correspond to the cross-shaped coupling gap, the unit antenna is provided with a reconfigurable balanced feeding mechanism to feed the coupling gap through a microstrip line, and a bridge structure is adopted at the junction of the microstrip lines.

[0012] Preferably: the broadband 90° adjustable phase shifter and the reconfigurable balanced feeding mechanism are used to control the excitation phase of the orthogonal feeding port corresponding to each unit antenna, and can generate vortex electromagnetic waves with two different polarizations (X-line polarization and Y-line polarization) and three different OAM modes.

[0013] (III) Beneficial effects

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The unit antenna can generate a broadband 180-degree phase difference through a reconfigurable balanced feeding mechanism.

[0016] 2. The unit antenna can produce two different polarization characteristics: X-line polarization and Y-line polarization. At the same time, it meets good polarization characteristics and good standing wave characteristics, and has wide bandwidth, low profile, small size, simple implementation and easy integration.

[0017] 3. When the present invention is used, the traditional PCB or LTCC process and 3D printing technology are used to manufacture the array antenna, and the entire array antenna is mainly composed of a metal magnetoelectric dipole and a microstrip line layer, by setting a one-to-four equal amplitude and equal phase power distributor, four one-to-two equal amplitude and equal phase power distributors, two broadband 90° adjustable phase shifters, and two delays in the microstrip line layer. Each unit antenna is provided with four feeding ports, and is respectively connected to the two output branches of the one-to-two equal amplitude and equal phase power distributor. The input ends of the two one-to-two equal amplitude and equal phase power distributors are respectively connected to the broadband 90° adjustable phase shifters, and the broadband 90° adjustable phase shifter is connected to the output end of the one-to-four equal amplitude and equal phase power distributor. The input ends of the other two one-to-two equal-amplitude and equal-phase power dividers are respectively connected to the delay device, and the delay device is connected to the output end of the one-to-four equal-amplitude and equal-phase power divider, thereby utilizing a broadband 90° adjustable phase shifter and a reconfigurable balanced feeding mechanism to control the excitation phase and polarization state of the corresponding port of each unit antenna, thereby changing the working polarization state and OAM mode of the array antenna.

[0018] 4. The array antenna can provide two different polarizations (X-line polarization and Y-line polarization) and three different OAM modes by changing the state of the broadband 90° adjustable phase shifter and the reconfigurable balanced feeding mechanism through a DC bias circuit, thereby satisfying better polarization characteristics, better standing wave characteristics, wider operating bandwidth and higher OAM purity. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the structure of a microstrip line layer on a dielectric substrate in a broadband OAM mode and polarization reconfigurable array antenna;

[0020] Figure 2 A structural diagram of a broadband OAM mode and polarization reconfigurable array antenna proposed by the present invention;

[0021] Figure 3 A schematic diagram of the structure of a metal grounding layer on a dielectric substrate in a broadband OAM mode and polarization reconfigurable array antenna proposed by the present invention;

[0022] Figure 4 A cross-sectional view of a broadband OAM mode and polarization reconfigurable array antenna proposed by the present invention;

[0023] Figure 5It is the test phase distribution diagram of different OAM modes of the array antenna at a frequency of 3.5GHz under X-line polarization state;

[0024] Figure 6 It is the test phase distribution diagram of different OAM modes of the array antenna under Y-line polarization state at a frequency of 3.5GHz;

[0025] Figure 7 The test return loss of the array antenna in the X-line polarization state ;

[0026] Figure 8 The test return loss of the array antenna in the Y-line polarization state ;

[0027] Fig. 9 It is the gain pattern of the array antenna at a frequency of 3.5 GHz in the X-line polarization state;

[0028] Fig.10 It is the gain pattern of the array antenna in the Y-line polarization state at a frequency of 3.5GHz;

[0029] In the figure: 1. dielectric substrate; 2. metal ground layer; 3. cross-shaped coupling gap; 4. metal magnetoelectric dipole; 5. unit antenna; 6. one-to-four equal-amplitude and equal-phase power divider; 7. DC bias circuit; 8. microstrip line; 9. delay device; 10. broadband 90° adjustable phase shifter; 11. one-to-two equal-amplitude and equal-phase power divider; 12. reconfigurable balanced feeding mechanism; 13. microstrip line layer. DETAILED DESCRIPTION

[0030] 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.

[0031] Example:

[0032] See attached Figure 1-4A broadband OAM mode and polarization composite reconfigurable array antenna comprises a dielectric substrate 1 and four unit antennas 5. A metal grounding layer 2 is provided on the upper surface of the dielectric substrate 1. The four unit antennas 5 are arranged on the metal grounding layer 2 to form a one-dimensional linear array. A cross-shaped coupling slot 3 is provided on the metal grounding layer 2. The unit antenna 5 is composed of four metal magneto-electric dipoles 4, and the metal magneto-electric dipoles 4 are used as radiators. The four metal magneto-electric dipoles 4 are equidistantly arranged and correspond to the cross-shaped coupling slots 3. The cross-shaped coupling slots 3 are excited by microstrip lines 8 so that the unit antennas 5 can be fed.

[0033] A microstrip line layer 13 is provided on the lower surface of the dielectric substrate 1. The microstrip line layer 13 is provided with a DC bias circuit 7 and is connected to a reconfigurable balanced feeding mechanism 12. The reconfigurable balanced feeding mechanism 12 feeds the unit antenna 5 and controls different excitation directions for the unit antenna 5, thereby generating different polarization states (X-line polarization and Y-line polarization) and initial phases.

[0034] The microstrip line layer 13 includes two broadband 90° adjustable phase shifters 10, one one-to-four equal amplitude and equal phase power distributor 6, four one-to-two equal amplitude and equal phase power distributors 11, two time delays 9, and twelve DC bias circuits 7. Each unit antenna is connected to the one-to-two equal amplitude and equal phase power distributor 11 through a reconfigurable balanced feeding mechanism 12. The input ends of two of the one-to-two equal amplitude and equal phase power distributors 11 are respectively connected to the broadband 90° adjustable phase shifters 10, and the broadband 90° adjustable phase shifters 10 are connected to the output end of the one-to-four equal amplitude and equal phase power distributor 6. The input ends of the other two of the one-to-two equal amplitude and equal phase power distributors 11 are respectively connected to the time delay 9, and the time delay 9 is connected to the output end of the one-to-four equal amplitude and equal phase power distributor 6. A variety of different phase combinations can be generated through the DC bias circuit 7 and the broadband 90° adjustable phase shifter 10, and two different linear polarization waves can be formed in the end, namely X-line polarization and Y-line polarization. At the same time, for each linear polarization wave, the array antenna can generate vortex electromagnetic waves of three different OAM modes. The array antenna has good polarization characteristics, good standing wave characteristics, wide working bandwidth and high OAM purity.

[0035] Based on the idea of ​​the present invention, a broadband polarization reconfigurable array antenna is manufactured using PCB technology and 3D printing technology, and relevant simulations and tests are performed: Figure 5 It is the test phase distribution diagram of different OAM modes of the array antenna at a frequency of 3.5GHz under X-line polarization state; Figure 6 It is the test phase distribution diagram of different OAM modes of the array antenna under Y-line polarization state at a frequency of 3.5GHz; Figure 7 It is the test return loss of the array antenna under X-line polarization state; Figure 8 is the test return loss of the array antenna in the Y-line polarization state; Fig. 9 It is the gain pattern of the array antenna at a frequency of 3.5 GHz in the X-line polarization state; Fig.10 The gain pattern of the array antenna in Y-polarization state at a frequency of 3.5 GHz. The results show that the array antenna can independently reconstruct the polarization and OAM modes and meet good performance.

[0036] It should be noted that the term "comprises" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article, or device that includes a series of elements includes not only those elements, but also includes other elements that are not explicitly listed, or also includes elements inherent to such process, method, article, or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article, or device that includes the element.

[0037] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A broadband OAM mode and polarization composite reconfigurable array antenna, comprising a dielectric substrate (1) and four unit antennas (5), characterized in that: A metal grounding layer (2) is provided on the upper surface of the dielectric substrate (1); four unit antennas (5) are arranged on the metal grounding layer (2) to form a 2×2 array; and a cross-shaped coupling slot (3) is engraved on the metal grounding layer (2); A microstrip line layer (13) is provided on the lower surface of the dielectric substrate (1), a DC bias circuit (7) is also provided on the microstrip line layer (13), the dielectric substrate (1) is connected to a reconfigurable balanced feeding mechanism (12) via the microstrip line layer (13), the reconfigurable balanced feeding mechanism (12) is used to feed the unit antenna (5) and simultaneously control different excitation directions applied to the unit antenna (5) to generate different polarization states and initial phases; The microstrip line layer (13) comprises: a one-to-four equal amplitude and equal phase power distributor (6), four one-to-two equal amplitude and equal phase power distributors (11), two time delays (9), two broadband 90° adjustable phase shifters (10) and twelve DC bias circuits (7); wherein the input ends of two of the one-to-two equal amplitude and equal phase power distributors (11) are respectively connected to the broadband 90° adjustable phase shifters (10), and the broadband 90° adjustable phase shifters (10) are connected to the output end of the one-to-four equal amplitude and equal phase power distributor (6); the input ends of the other two of the one-to-two equal amplitude and equal phase power distributors (11) are respectively connected to the time delays (9), and the time delays (9) are connected to the output end of the one-to-four equal amplitude and equal phase power distributor (6); The unit antenna (5) is composed of four metal magnetic electric dipoles (4), and the metal magnetic electric dipoles (4) serve as radiators. The four metal magnetic electric dipoles (4) are respectively located in four quadrants and correspond to the cross-shaped coupling slot (3). The unit antenna (5) is fed by exciting the cross-shaped coupling slot (3) using a microstrip line (8).

2. The broadband OAM mode and polarization composite reconfigurable array antenna according to claim 1, characterized in that: The reconfigurable balanced feeding mechanism (12) controls the excitation phase of the orthogonal feeding port of the unit antenna (5), and can generate two different phase states and two different linear polarization waves, the two different phase states being 0° and -180°; the broadband 90° adjustable phase shifter (10) controls the excitation phase of the orthogonal feeding ports of two of the unit antennas (5), and the corresponding unit antennas (5) can generate four different phase states, the four different phase states being 0°, -90°, -180°, and -270°.

3. The broadband OAM mode and polarization composite reconfigurable array antenna according to claim 1, characterized in that: The four unit antennas (5) can form two different linear polarization waves according to different phase combinations: X-linear polarization and Y-linear polarization; for each linear polarization wave state, the array antenna can generate vortex electromagnetic waves of three different OAM modes, and the three different OAM modes are -1, 0, and +1 orders.

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