A broadband polarization angle continuously adjustable antenna based on an electrically controlled metasurface

Abstract

The present invention discloses a broadband polarization angle continuously adjustable antenna based on an active electromagnetic metasurface, which includes a linearly polarized slot-coupled microstrip antenna and an active electromagnetic metasurface capable of continuously adjusting the linear polarization inclination angle. The linearly polarized slot-coupled microstrip antenna is a feed source, which is excited by the slot-coupling method and can radiate a single linearly polarized wave within a wide frequency band. The active electromagnetic metasurface is composed of electromagnetic units arranged in an array, and an H-shaped metal strip structure and diodes are integrated inside. By changing the forward bias voltage of the diodes, the on-resistance is adjusted, driving the amplitude of the orthogonal transmitted electric field components to change, thereby realizing the polarization angle control of the antenna. The present invention realizes the real-time change of the polarization angle of electromagnetic waves. The antenna exhibits good working characteristics within a wide frequency band, can effectively improve the compatibility and integration of linearly polarized antennas, and has good application prospects in the fields of airborne communication, electronic countermeasure, polarization imaging, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of linearly polarized reconfigurable antennas, and particularly to a broadband polarization angle continuously adjustable antenna based on an electrically controlled metasurface. Background Art

[0002] In order to improve the functionality and channel capacity of antennas, polarization reconfiguration technology has been widely applied in antenna design in recent years. The developed antenna samples have the characteristics of high integration, good flexibility, and rich functions, and are applied in synthetic aperture radar, satellite communication, polarization coding communication and other scenarios, effectively improving the communication and imaging quality. Among them, the linearly polarized rotating antenna can transmit and receive multi-angle linearly polarized waves based on a single channel by means of time-sharing switching of functional states, which can be used to overcome the polarization mismatch problem for moving targets, achieve polarization alignment during point-to-point signal transmission, and is beneficial to reducing the weight, power consumption and cost of the system, and has good application prospects in platforms such as spaceborne and airborne platforms.

[0003] Currently, research teams at home and abroad have proposed a variety of linearly polarized rotating antenna designs combined with electrically controlled radio frequency components, but generally can only complete a 90° step of the polarization angle and have fewer functional states. To achieve continuous and free adjustment of the linearly polarized angle, some researchers have used a quadrature dual circularly polarized antenna as the basis and used a phase shifter to adjust the phase difference between the two circularly polarized signals to achieve the synthesis of linearly polarized waves at any inclination angle. However, this scheme has a narrow working bandwidth, and at the same time, introducing a phase shifter will increase the antenna size and complicate the feeding line. A metasurface is a two-dimensional composite material composed of sub-wavelength periodic electromagnetic units, which has the advantages of flexible and controllable properties, light weight and easy integration. In recent years, a series of major progress has been made in the field of electromagnetic regulation, especially in the design of new antennas, providing an excellent way to construct miniaturized and highly integrated antennas. Some researchers have designed an artificial magnetic conductor based on the metasurface concept and proposed a polarization reconfiguration method by combining a dipole antenna on it. However, the switching of its polarization state is completed by changing the capacitance, and the working frequency shifts with the change of the capacitance value, resulting in difficulty in obtaining a wide overlapping frequency band in different states for such antennas. To adjust the polarization angle of a horn antenna, domestic researchers have proposed a reflective polarization rotating metasurface, which also uses the method of regulating the phase of the orthogonal circular polarization components to control the polarization angle of the outgoing wave of the linearly polarized horn antenna, but this design still has the problem of too narrow a working bandwidth, limiting its application range. Summary of the Invention

[0004] The object of the present invention is to provide a broadband polarization angle continuously adjustable antenna based on an electronically controlled metasurface. By loading an electronically controlled metasurface above a single linearly polarized antenna, the real-time change of the polarization angle of electromagnetic waves is realized. At the same time, due to the resistive adjustment method, the antenna exhibits good working characteristics in a wide frequency band, which can effectively improve the compatibility and integration of linearly polarized antennas, and has good application prospects in fields such as airborne communication, electronic countermeasure, and polarization imaging.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention uses a linearly polarized slot-coupled microstrip antenna as a feed source, and loads an electronically controlled polarization conversion metasurface above it to realize continuous adjustment of the inclination angle of the outgoing linearly polarized wave. The active electronically controlled metasurface proposed by the present invention is composed of periodically arranged electromagnetic units. Both sides of the unit are covered with H-shaped metal strip structures, and a pin diode is integrated inside. As the amplitude of the forward bias voltage at both ends of the pin diode changes, the on-resistance of the pin diode also changes accordingly. This resistive control mechanism combined with the H-shaped metal strip structure can realize the amplitude control of the orthogonal transmitted polarization electric field components, thereby synthesizing linearly polarized transmitted waves with different inclination angles.

[0007] A broadband polarization angle continuously adjustable antenna based on an electronically controlled metasurface includes a linearly polarized slot-coupled microstrip antenna and an active electronically controlled metasurface arranged above it. The active electronically controlled metasurface has the ability of polarization control. The realization of polarization control is to perform amplitude control on the orthogonal linearly polarized components in linearly polarized electromagnetic waves, and realize the rotation of the polarization angle by changing the amplitude ratio.

[0008] The active electronically controlled metasurface is formed by arranging multiple electromagnetic unit arrays. The electromagnetic unit includes a dielectric substrate, and the dielectric substrate includes opposite first and second surfaces; two symmetrically arranged H-shaped metal strip structures are provided on both the first surface and the second surface; the H-shaped metal strip structure on the second surface has the same structure as the H-shaped metal strip structure on the first surface, and the H-shaped metal strip structure on the second surface is obtained by rotating the H-shaped metal strip structure on the first surface clockwise by 90° and then horizontally flipping it.

[0009] A pin diode is provided in the middle of the H-shaped metal strip structure. The two H-shaped metal strip structures are connected by a DC bias line, and the two ends of the DC bias line are respectively connected to the forward bias end and the reverse bias end of the pin diode. In the case of forward bias, it can be equivalently regarded as a series branch of a resistor and an inductor, and the resistor can be non-linearly adjusted by changing the voltage at both ends of the pin diode.

[0010] In a specific embodiment, there is a gap between the linearly polarized slot-coupled microstrip antenna and the active electronically controlled metasurface, and the active electronically controlled metasurface completely covers the linearly polarized slot-coupled microstrip antenna.

[0011] In a specific embodiment, a feeding thin line is provided outside the H-shaped metal strip structure, and the feeding thin line is connected to the H-shaped metal strip structure through a DC bias line. The feeding thin line feeds the pin diodes in different electromagnetic units in a parallel manner. The feeding thin line feeds the pin diodes in different electromagnetic units in a parallel manner.

[0012] In a specific embodiment, a first inductor is provided on the DC bias line between two of the H-shaped metal strip structures, and a second inductor is provided on the DC bias line between the feeding thin line and the H-shaped metal strip structure.

[0013] In a specific embodiment, the linearly polarized slot-coupled microstrip antenna includes a feeding layer and a radiation layer provided above the feeding layer, and a gap is left between the radiation layer and the feeding layer.

[0014] In a specific embodiment, the radiation layer includes a dielectric substrate and a radiation patch provided on the surface of the dielectric substrate for radiating u polarized waves.

[0015] In a specific embodiment, the feeding layer includes: a dielectric substrate, the dielectric substrate includes a first surface and a second surface opposite to each other; a metal probe microstrip line is provided on the first surface, the second surface is a metal layer, and a slot is etched on the metal layer. The projection of the metal probe microstrip line on the metal layer intersects with the slot, and the metal probe microstrip line is used for coupling and feeding the slot.

[0016] In a specific embodiment, the metal probe microstrip line is in a U-shaped structure, and the two arms of the U-shaped metal probe microstrip line are perpendicular to the slot in the projection on the metal layer.

[0017] In a specific embodiment, bending portions bent outward are provided at the ends of the two arms of the U-shaped metal probe microstrip line.

[0018] In a specific embodiment, the two arms of the metal probe microstrip line are arranged at an angle of 45° with the horizontal direction, and the slot is arranged at an angle of 135° with the horizontal direction.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The present invention realizes continuous adjustment of the linear polarization inclination angle, solves the problem of too narrow bandwidth existing in the existing design to a certain extent, and at the same time has the characteristics of simple configuration and easy popularization, providing a useful reference for the flexible regulation of antenna polarization parameters and the realization of low-cost multi-functional integration in modern wireless communication systems.

[0021] The linearly polarized slot-coupled microstrip antenna of the present invention can efficiently transmit and receive electromagnetic waves in a wide frequency band, and at the same time can achieve good compatibility with the active electronically controlled metasurface. When the active electronically controlled metasurface is combined with the microstrip antenna, the polarization angle of the radiated wave can be continuously adjusted by an external bias voltage. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the overall structure of the present invention;

[0023] Figure 2 Schematic diagram of the orthogonal decomposition of linearly polarized waves in the embodiment of the present invention;

[0024] Figure 3 Schematic diagram of the working mechanism of the antenna with continuously adjustable polarization angle in the embodiment of the present invention;

[0025] Figure 4 Schematic diagram of the structure of the electromagnetic unit of the active electronically controlled metasurface in the embodiment of the present invention; (a) is the front structure diagram of the electromagnetic unit, and (b) is the back structure diagram of the electromagnetic unit;

[0026] Figure 5 Schematic diagram of the equivalent circuit of the electromagnetic unit of the active electronically controlled metasurface in the embodiment of the present invention;

[0027] Figure 6 Schematic diagram of the transmission coefficient and polarization angle of the active electronically controlled metasurface in the embodiment of the present invention; (a) is x - y Schematic diagram of the transmission coefficient in the coordinate system, (b) is u - v Schematic diagram of the transmission coefficient in the coordinate system, (c) is the schematic diagram of the polarization angle;

[0028] Figure 7 Schematic diagram of the front structure of the radiation layer in the embodiment of the present invention;

[0029] Figure 8 Schematic diagram of the front structure of the feeding layer in the embodiment of the present invention;

[0030] Figure 9 Schematic diagram of the back structure of the feeding layer in the embodiment of the present invention;

[0031] Figure 10 Side view of the linearly polarized slot-coupled microstrip antenna in the embodiment of the present invention;

[0032] Figure 11 Schematic diagram of the reflection coefficient and gain of the linearly polarized slot-coupled microstrip antenna in the embodiment of the present invention;

[0033] Figure 12 Schematic diagram of the reflection coefficient of the present invention in various states;

[0034] Figure 13 Schematic diagram of the polarization angle of the present invention in various states.

[0035] As shown in the figure:

[0036] 1. Active electronically controlled metasurface, 2. Radiation layer, 3. Feeding layer, 4. PIN diode, 5. First inductor, 6. Second inductor, 7. Feeding thin line, 8. DC bias line, 9. Bending part, 10. First sub - microstrip line, 11. Signal input terminal, 12. Second sub - microstrip line, 13. Slot, 14. Radiation patch, 15. Metal probe microstrip line, 16. Third sub - microstrip line. Detailed implementation manner

[0037] 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; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0038] Please refer to Figure 1 , in this embodiment, the S - band is used as the target frequency band. A broadband polarization angle continuously adjustable antenna based on an electronically controlled metasurface includes a linearly polarized slot - coupled microstrip antenna and an active electronically controlled metasurface 1 disposed above it. The active electronically controlled metasurface 1 is formed by arranging an array of 6×6 electromagnetic units to form a metasurface with a size of 120 mm×120 mm×1 mm, and its vertical distance from the linearly polarized slot - coupled microstrip antenna directly below is 41.3 mm.

[0039] The process of the present invention to achieve polarization angle regulation is as Figures 2 - 3 shown, Figure 2 shown, which describes the process of orthogonal decomposition of the transmitted electric field. For any obliquely polarized wave, its electric field can be orthogonally decomposed into components , along the , directions. The phases of the two components are the same, and the polarization direction of the electromagnetic wave and the axis between the included angle can be obtained by the following formula:

[0040] (1);

[0041] If the metasurface is used to independently regulate the amplitudes of the two components, the free adjustment of the angle can be achieved. According to this method, polarization regulation is carried out in this embodiment, and the specific working process is as Figure 3As shown, the bottom linearly polarized slot-coupled microstrip antenna radiates a polarized wave along the +z direction. After interacting with the active electronically controlled metasurface 1, a part of the polarized transmission component will be excited. Then, it combines with the polarized component to form an obliquely polarized transmission wave. By adjusting the metasurface with an external bias voltage, the polarization angle can be controlled, and the tilt angle can be continuously adjusted within the range of ±45°. The polarized wave, after interacting with the active electronically controlled metasurface 1, will excite a part of the polarized transmission component, and then combines with the polarized component to form an obliquely polarized transmission wave. By adjusting the metasurface with an external bias voltage, the polarization angle can be controlled, and the tilt angle can be continuously adjusted within the range of ±45°.

[0042] As Figure 4 shown, the electromagnetic unit includes a dielectric substrate made of FR4 material with a relative dielectric constant of 4.2 and a thickness of 1.6 mm. Both the upper surface and the lower surface of the dielectric substrate are provided with 2 symmetrically arranged H-shaped metal strip structures; the H-shaped metal strip structure on the lower surface has the same structure as that on the upper surface, and its direction is obtained by rotating the H-shaped metal strip structure on the upper surface clockwise by 90° and then horizontally flipping it.

[0043] A pin diode 4 is provided in the middle of the H-shaped metal strip structure. The two H-shaped metal strip structures are connected by a DC bias line 8, and the two ends of the DC bias line 8 are respectively connected to the forward bias end and the reverse bias end of the pin diode 4. The model of the pin diode 4 is Infineon BAR50-02V. In the case of forward bias, it can be equivalent to a series branch of a resistor and an inductor. By changing the voltage across the pin diode 4, the resistance can be non-linearly adjusted.

[0044] A feeding thin wire 7 is provided outside the H-shaped metal strip structure. The feeding thin wire 7 is located at the edge of the dielectric substrate of the electromagnetic unit and is connected to the H-shaped metal strip structure through the DC bias line 8. The feeding thin wire 7 feeds the pin diodes 4 in different electromagnetic units in parallel.

[0045] To avoid crosstalk of the feeding thin wire to the electromagnetic structure, a patch inductor is loaded above it as isolation. Therefore, a 60 nH first inductor 5 is provided on the DC bias line 8 between the two H-shaped metal strip structures, and a 20 nH second inductor 6 is provided on the DC bias line 8 between the feeding thin wire 7 and the H-shaped metal strip structure.

[0046] As Figure 4 shown, where w 1 = 1.0 mm, w 2 = 0.2 mm, l 1 = 8.7 mm, l 2 = 4.5 mm, l 3 = 6.9 mm, g 1 = 1.3 mm, g 2 = 0.2 mm, p1 = 20.0 mm. The active electronically controlled metasurface 1 has the ability of polarization control. Achieving polarization control is to perform amplitude control on the orthogonal linearly polarized components in linearly polarized electromagnetic waves, and to realize the rotation of the polarization angle by changing the amplitude ratio.

[0047] Since there is no metal plane between the H-shaped metal strip structures on the front and back sides of the dielectric substrate, spatial coupling can be carried out, and there are no metal vias, so there is no current conduction either. The electromagnetic units in the active electronically controlled metasurface 1 are oriented in the same direction, and there is no phase gradient, so there will be no deflection of the transmitted beam.

[0048] As Figure 5 shown, where L 0 is the inductance shown by the transverse metal strip along the x direction, C 0 is the equivalent capacitance of adjacent metal strips along the x direction. When the x polarized wave is incident, the H-shaped metal strip structure together with the pin diode 4 can be equivalent to an RLC series resonance circuit. When the resistance of the pin diode 4 changes, the transmission coefficient near the resonance frequency will change significantly, so as to independently control the incident x polarization component. Moreover, the change in resistance value will not affect the resonance frequency, avoiding the frequency band shift caused by the switching of the working state, which is beneficial to obtaining a wider overlapping frequency band. The working mechanism of the structure on the lower surface of the electromagnetic unit is similar, and the y polarized electric field component can be independently controlled. The transmission characteristics of the electromagnetic unit when the resistance of the pin diode 4 changes are as Figure 6 shown, where R x and R y are the resistances of the pin diodes 4 located on the front and back sides of the electromagnetic unit respectively. In the figure, taking the separate control with R x as an example, R y is fixed at 12960 Ω. First, from Figure 6 (a), it can be seen that when R x increases exponentially from 10 Ω to 12960 Ω, the co-polarization transmission coefficient x in the t xx direction gradually increases, while t yy remains constant. At the same time, from Figure 6 (b), it can be seen that as the resistance increases, the polarization component in the transmitted wave gradually increases from 0 until it is equal to the polarization component, which means that the polarization direction of the transmitted wave changes from The direction rotates step by step clockwise towards the direction (electromagnetic wave polarization angle). When and components are equal, the polarization of the transmitted wave will be parallel to y axis. The polarization angle is as shown in Figure 6 (c). When R x is increased alone, the polarization angle can gradually increase from 0° to 45° within 2.0 - 4.0 GHz, and the polarization angle within the band changes stably with frequency. Due to the symmetry of this electromagnetic structure about x axis and y axis, if R x is fixed at 12960Ω and R y is independently regulated, the change range of the polarization angle can cover 0° to -45°.

[0049] As shown in Figure 10 , the linearly polarized slot-coupled microstrip antenna includes a feeding layer 3 and a radiation layer 2 arranged above the feeding layer 3. The vertical distance between the radiation layer 2 and the feeding layer 3 below is h 1 = 11.76 mm. The dielectric substrates used for the radiation layer 2 and the feeding layer 3 are both rectangular substrates with a side length of 54 mm.

[0050] As shown in Figure 7 , the radiation layer 2 includes a dielectric substrate and a radiation patch 14 arranged on the surface of the dielectric substrate. The radiation patch 14 is a rectangular metal patch, arranged at 45° with the dielectric substrate, and is used for radiating u polarized waves.

[0051] As shown in Figures 8 - 9 , the feeding layer 3 includes: a dielectric substrate, the dielectric substrate includes opposite first and second surfaces; a metal probe microstrip line 15 is arranged on the first surface, the second surface is a metal layer, and a slot 13 is etched on the metal layer. The metal probe microstrip line 15 is used for coupling and feeding the slot 13, and the slot 13 is a rectangular slot.

[0052] The metal probe microstrip line 15 is of a U-shaped structure, which can excite a radiation field at the gap 13 and can be used to excite the upper rectangular radiation patch 14. The metal probe microstrip line 15 includes two first sub-microstrip lines 10 and second sub-microstrip lines 12 arranged in parallel. A third sub-microstrip line 16 perpendicular to the first sub-microstrip line 10 and the second sub-microstrip line 12 is provided at the same end of the first sub-microstrip line 10 and the second sub-microstrip line 12. The other ends of the first sub-microstrip line 10 and the second sub-microstrip line 12 are provided with bent portions 9 that are bent outward, and the bent portions 9 are parallel to the third sub-microstrip line 16. The third sub-microstrip line 16 is connected to a signal input terminal 11. There is a bent portion in the middle of the input terminal 11, one end is connected to the middle of the third sub-microstrip line 16, and the other end extends to the edge of the dielectric substrate.

[0053] The first sub-microstrip line 10 and the second sub-microstrip line 12 of the metal probe microstrip line 15 are arranged at an angle of 45° with the horizontal direction, and the gap 13 is arranged at an angle of 135° with the horizontal direction.

[0054] As Figures 7 - 10 shown, the parameters in the figure are as follows: l 4 = 28.36 mm, l 5 = 11.63 mm, l 6 = 38.79 mm, w 3 = 2.32 mm, w 4 = 0.59 mm, w 5 = 2.35 mm, g 3 = 2.42 mm, p 2 = 54.0 mm, t 1 = 1.0 mm, t 2 = 1.6 mm, h 1 = 11.76 mm.

[0055] Figure 11 The reflection coefficient and gain of the antenna are shown. In the range of 2.43 - 3.72 GHz, |S11| is lower than -10 dB and the gain is higher than 4 dBi, and the relative bandwidth is 41.6%, which proves that the linearly polarized slot-coupled microstrip antenna can provide stable excitation for the active electronically controlled metasurface 1 within a wide frequency band.

[0056] When the active electronically controlled metasurface and the linearly polarized slot-coupled microstrip antenna work together, the resistance values are selected with the goal of achieving a 10° step in the polarization angle, and simulation calculations are carried out. First, the reflection coefficients of the antenna in each state are as Figure 12 shown. In the range of 2.43 - 3.67 GHz, the reflection coefficient of the antenna is always lower than -10 dB, and the relative operating bandwidth is 40.7%. The polarization angles of the radiation waves corresponding to different resistance values are as Figure 13As shown, within the range of 2.9 - 3.7 GHz, the continuous step - by - step regulation of the polarization angle can be achieved through the adjustment of the resistance, and the variation range covers ±45°, which proves that the present invention can achieve the continuous adjustment of the linear polarization dip angle within a wide frequency band. Compared with the existing electronically controlled linear polarization rotating antenna, this design has obvious advantages in terms of bandwidth.

Claims

1. A broadband polarization angle continuously adjustable antenna based on an electrically controlled metasurface, characterized in that: It comprises a linearly polarized slot-coupled microstrip antenna and an active electrically controlled metasurface (1) arranged above the linearly polarized slot-coupled microstrip antenna; The active electrically controlled metasurface (1) is formed by an array of multiple electromagnetic units, wherein the electromagnetic units include a dielectric substrate, wherein the dielectric substrate includes a first surface and a second surface opposite to each other; the first surface and the second surface are both provided with two symmetrically arranged H-shaped metal strip structures; the H-shaped metal strip structure on the second surface is the same as the H-shaped metal strip structure on the first surface, and the H-shaped metal strip structure on the second surface is obtained by rotating the H-shaped metal strip structure on the first surface clockwise by 90° and then flipping it horizontally; A pin diode (4) is provided in the middle of the H-shaped metal strip structure, and the two H-shaped metal strip structures are connected via a DC bias line (8), and the two ends of the DC bias line (8) are respectively connected to the forward bias end and the reverse bias end of the pin diode (4); There is a gap between the linearly polarized slot-coupled microstrip antenna and the active electrically controlled metasurface (1), and the active electrically controlled metasurface completely covers the linearly polarized slot-coupled microstrip antenna; The linearly polarized slot-coupled microstrip antenna comprises a feeding layer (3) and a radiation layer (2) arranged above the feeding layer (3); The feeding layer (3) comprises: a dielectric substrate, the dielectric substrate comprising a first surface and a second surface opposite to each other; The first surface is provided with a metal probe microstrip line (15), the second surface is a metal layer, a gap (13) is etched on the metal layer, a projection of the metal probe microstrip line (15) on the metal layer intersects with the gap (13), and the metal probe microstrip line (15) is used to couple and feed the gap (13).

2. According to claim 1, a broadband polarization angle continuously adjustable antenna based on an electrically controlled metasurface is characterized in that: A feeding thin wire (7) is provided on the outside of the H-shaped metal strip structure, and the feeding thin wire (7) and the H-shaped metal strip structure are connected via a DC bias line (8). The feeding thin wire (7) enables the pin diodes (4) in different electromagnetic units to be fed in parallel.

3. According to claim 2, a broadband polarization angle continuously adjustable antenna based on an electrically controlled metasurface is characterized in that: A first inductor (5) is provided on the DC bias line (8) between the two H-shaped metal strip structures, and a second inductor (6) is provided on the DC bias line (8) between the feed fine wire (7) and the H-shaped metal strip structure.

4. According to claim 1, a broadband polarization angle continuously adjustable antenna based on an electrically controlled metasurface is characterized in that: The radiation layer (2) comprises a dielectric substrate and a radiation patch (14) arranged on the surface of the dielectric substrate.

5. According to claim 1, the broadband polarization angle continuously adjustable antenna based on electrically controlled metasurface is characterized in that: The metal probe microstrip line (15) is a U-shaped structure, and the projections of two arms of the metal probe microstrip line (15) of the U-shaped structure on the metal layer are perpendicular to the gap (13).

6. The broadband polarization angle continuously adjustable antenna based on electrically controlled metasurface according to claim 5, characterized in that: The ends of the two arms of the U-shaped metal probe microstrip line (15) are both provided with bent portions (9) bent outwards.

7. The broadband polarization angle continuously adjustable antenna based on electrically controlled metasurface according to claim 6, characterized in that: The two arms of the metal probe microstrip line (15) are arranged at 45 degrees to the horizontal direction, and the gap (13) is arranged at 135 degrees to the horizontal direction.

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