Polarization reconfigurable reflection enhancement metasurface and method

Abstract

The invention discloses a polarization reconfigurable reflection enhancement metasurface and a method. A radiation antenna of a radiation unit and a back-loaded circuit are integrally designed into a three-dimensional integrated architecture; each radiation unit is specifically of a three-layer radiation metal sheet structure, an antenna radiation layer and a radio frequency amplification circuit layer are separated by a metal ground shared by the antenna radiation layer and the radio frequency amplification circuit layer, and a medium is filled between metal sheets; the first layer is an antenna radiation layer and is provided with a radiation patch; the second layer is a metal ground, is provided with a co-polarization coupling feed slot and a cross-polarization coupling feed slot, and is used for slot coupling feed; and the third layer is a radio frequency amplification circuit layer, is provided with a back-loaded circuit, and feeds the radiation patch of the first layer through electromagnetic coupling. According to the invention, switching of two states of co-polarization and cross-polarization reflection of the metasurface can be realized; the reflection amplitude of the metasurface can be enhanced, and the metasurface has the characteristic of low profile.

Description

Technical Field

[0001] This invention belongs to the field of antenna engineering technology, and in particular relates to a polarization-reconfigurable reflection-enhancing metasurface. Background Technology

[0002] With the continuous development of modern information technology, the demand for multifunctional antennas and solutions to complex application environments is constantly increasing. The design of electromagnetic reflective surfaces is no longer satisfied with a single electromagnetic wave control function. Multifunctionality, intelligence, and integration have become new requirements for electromagnetic structure design.

[0003] Polarization-reconfigurable reflective metasurfaces have wide applications in the communications field. Reflective surface-reconfigurable (RSS) devices act as decoys to interfere with the enemy and provide cover for friendly targets. In communication systems, introducing polarization-reconfigurable reflective surfaces can achieve high-quality multi-user communication. Polarization refers to the orientation of an electric field vector in space. Common polarization methods include linear polarization and circular polarization, while dual polarization can improve spectral efficiency and communication system performance. Traditional reflective surfaces, in practical polarization switching, often only achieve reflection enhancement in a single polarization direction, failing to meet the demand for dual-polarization reflection enhancement in complex communication environments. Existing technologies struggle to flexibly switch between co-polarization and cross-polarization reflection enhancement states. Therefore, developing a reflective metasurface capable of switching between co-polarization and cross-polarization reflection enhancement states, with a compact structure and high integration, is of significant practical importance.

[0004] The future development trend is the integrated design of antenna arrays, RF components and platforms, and the development of antennas towards integration. This invention proposes a mechanism for loading active circuits into the antenna back cavity, which is of great significance for antenna integration and design. Summary of the Invention

[0005] The purpose of this invention is to propose a method for controlling reflected electromagnetic waves using an antenna back-mounted circuit. The realization of a polarization-reconfigurable reflection-enhancing metasurface has significant academic and engineering application value, and can provide a multifunctional, intelligent, and integrated effective solution for research hotspots in electronic information fields such as millimeter-wave automotive radar, wireless power transmission, and smart skin. Through the metasurface with dual-polarization reflection enhancement function proposed in this invention, the problems of difficulty in achieving dual-polarization reflection enhancement function state switching, complex structure, and low integration in existing technologies are addressed.

[0006] To achieve the objectives of this invention, a polarization-reconfigurable reflection-enhancing metasurface is disclosed, comprising multiple radiating elements. The radiating antenna and back-mounted circuit of each radiating element are integrated into a three-dimensional architecture. Each radiating element is specifically a three-layer radiating metal sheet structure. The antenna radiating layer and the RF amplifier circuit layer are separated by a shared metal ground, and the spaces between the metal sheets are filled with a dielectric. The first layer is the antenna radiating layer, on which a radiating patch is disposed. The second layer is a metal ground, on which common-polarization coupling feed slots and cross-polarization coupling feed slots are disposed for slot coupling feed. The third layer is the RF amplifier circuit layer, on which a back-mounted circuit is disposed, feeding the radiating patch of the first layer through electromagnetic coupling.

[0007] Furthermore, the radiating patch is a radiating patch for a dual-polarized microstrip antenna, serving both as a receiving antenna for receiving electromagnetic waves and as a transmitting antenna for transmitting reflected electromagnetic waves processed by radio frequency circuitry.

[0008] Furthermore, the common polarization coupled feed slots and the cross polarization coupled feed slots are arranged perpendicularly to each other.

[0009] Furthermore, the RF amplifier circuit layer includes a Wilkinson power divider, an RF amplifier, an RF switch, and a phase shifter; the Wilkinson power divider is connected to a common-polarization coupled feed slot via a microstrip line, and the output of the Wilkinson power divider is connected to the input of the RF amplifier; the RF amplifier is connected to the RF switch, the first output port of the RF switch is connected to the cross-polarization coupled feed slot, and the second output port is connected to the microstrip circuit of the next radiating unit.

[0010] Furthermore, the Wilkinson power divider includes a common polarization input port and two output branches. The Wilkinson power divider is connected to the common polarization coupling feed slot through the common polarization input port, and a resistor R1 is placed between the two output branches. One output branch is connected to a capacitor C1, which is connected to the input terminal of the RF amplifier. The other output branch is connected to a capacitor C5 via a phase shifter and is connected to the RF switch output terminal of the previous radiating unit.

[0011] Furthermore, capacitor C4 is connected to the power supply port of the RF amplifier and the power supply, inductor L1 is connected to the output terminal of the RF amplifier and the power supply, and the output terminal of the RF amplifier is connected to the input terminal of the RF switch through capacitor C2.

[0012] Furthermore, the first output port of the RF switch is connected to the cross-polarization feed port via capacitor C3, thereby connecting to the cross-polarization coupling feed slot; the second output port of the RF switch is connected to the microstrip circuit of the next radiating unit.

[0013] To achieve the objectives of this invention, a polarization-reconfigurable reflection enhancement method is also disclosed. The radiating patch and back-mounted circuitry of each radiating element are integrated into a three-dimensional integrated architecture. The RF amplifier, RF switch, Wilkinson power divider, and phase shifter are integrated into the antenna back cavity using a multi-layer PCB process. The radiating patch serves as both a receiving antenna to receive electromagnetic waves and a transmitting antenna to transmit reflected electromagnetic waves processed by the RF circuitry. The back-mounted circuitry includes power divider, amplification, switching, and phase-shifting functions to control the incident electromagnetic waves. The switching between common-polarization reflection and cross-polarization reflection is achieved through the on / off state of the RF switch.

[0014] Furthermore, the isolation between the two output ports of the Wilkinson power divider ensures that the electromagnetic waves received by each radiating element are radiated out of the next radiating element and will not be transmitted to other radiating elements; the phase shifter is a microstrip delay line that performs phase shifting processing on the signal and can set the phase gradient of the reflecting surface to control the reflection angle of the reflected wave.

[0015] Furthermore, the metasurface scattering mechanism is "received and then re-radiated," thereby altering the scattering characteristics of the metasurface array. The electromagnetic wave received by radiating element A is transmitted through a non-reciprocal circuit to its next adjacent radiating element B for re-radiation. Similarly, the electromagnetic wave received by radiating element B is transmitted through another non-reciprocal phase shifter to its next radiating element C for re-radiation, and so on for other elements. During cross-polarization reflection, the electromagnetic wave received by radiating element A is transmitted through a non-reciprocal circuit to the cross-polarization port of radiating element A for re-radiation. The electromagnetic wave received by each radiating element is transmitted through a radio frequency circuit to that radiating element for re-radiation, thus achieving polarization conversion.

[0016] Compared with the prior art, the significant advancements of this invention are: 1) It can achieve switching between common polarization and cross polarization reflection states of the metasurface; 2) It can enhance the reflection amplitude of the metasurface. The electromagnetic wave received by the receiving patch has power loss after passing through the circuit, but the amplifier can compensate for the loss and amplify the power. Therefore, theoretically, the signal radiated after incident has gain, which can increase the reflection amplitude of the metasurface; 3) Low profile, with a total thickness of about 2mm.

[0017] To more clearly illustrate the functional characteristics and structural parameters of the present invention, further explanation is provided below in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0019] Figure 1 This is a schematic diagram of the electromagnetic wave reflection path.

[0020] Figure 2 This is a schematic diagram of the overall structure;

[0021] Figure 3 This is a schematic diagram of the back cavity circuit.

[0022] The attached diagram is labeled as follows: 1-Radiating patch; 2-Common polarization coupled feed slot; 3-Cross polarization coupled feed slot; 4-Wilkinson power divider; 5-RF amplifier; 6-RF switch; 7-Phase shifter; 8-Resistor R1; 9-Capacitor C1; 10-Capacitor C2; 11-Capacitor C3; 12-Capacitor C4; 13-Capacitor C5; 14-Inductor L1. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] A polarization-reconfigurable reflection-enhancing metasurface and method are presented. The main concept involves a receiving antenna receiving electromagnetic waves, which are then amplified by an RF circuit before being transmitted by a transmitting antenna. The receiving and transmitting antennas are shared, and the RF circuitry is used to modify the amplitude and phase of the electromagnetic waves. Compared to Van Atta backscatter arrays, the proposed cascaded radiation structure reduces trace length and allows for the adjustment of the delay line phase shifter to achieve arbitrary reflection phase gradient design, thus enabling arbitrary reflected beamforming. A switch selects the path of the reflected electromagnetic wave, allowing for switching between cross-polarized transmission and common-polarized reflection. Cross-polarized reflection is achieved from the cross-polarization port of the receiving unit, while common-polarized reflection is achieved from the common-polarization port of the adjacent unit. Furthermore, the embedding of active devices provides significant freedom for varying the amplitude of the electromagnetic waves. In summary, this method embeds electrically controllable components into an electromagnetic radiation device, allowing for manipulation of its return gain and polarization characteristics by adjusting the external control voltage.

[0025] The scattering mechanism of this structure is "receive-re-radiation," which alters the scattering characteristics of the metasurface array. Unlike other "receive-re-radiation" structures, this structure differs in that during common-polarization reflection, the electromagnetic wave received by cell A is transmitted via a non-reciprocal circuit to its adjacent cell B for re-radiation. Similarly, the electromagnetic wave received by cell B is transmitted via another non-reciprocal phase shifter to its next cell C for re-radiation, and so on for other cells. During cross-polarization reflection, the electromagnetic wave received by cell A is transmitted via a non-reciprocal circuit to the cross-polarization port of cell A for re-radiation. The electromagnetic wave received by each patch cell is transmitted via an RF circuit to that patch cell for re-radiation, achieving polarization conversion. The unidirectional isolation of the transistor amplifier allows the received electromagnetic wave to flow along the set phase gradient direction within the series array. Furthermore, the gain characteristics of the transistor amplifier increase the amplitude of the re-radiated electromagnetic wave. The isolation between the two output ports of the Wilkinson power divider ensures that during common-polarization reflection, the electromagnetic wave received by cell A is essentially re-radiated from the next cell B and does not travel to cell C. In summary, the mechanism of this structure is to change the amplitude and phase of the reflected wave through amplifiers and phase shifters, and to select the path of the reflected electromagnetic wave through switches, thereby achieving a reconfigurable design of the common polarization and cross polarization scattering characteristics within the entire array band.

[0026] A slot-coupled microstrip patch antenna was chosen as the radiating element. This type of antenna is simple to fabricate and easy to integrate with RF circuitry. The dual-polarized antenna serves as both a receiving antenna to receive electromagnetic waves and a transmitting antenna to transmit reflected electromagnetic waves processed by the RF circuitry. The metal ground is located between two dielectric substrates, and the antenna radiating layer and the RF amplifier circuit layer are separated by a shared metal ground. This advantage significantly reduces the impact of the back-mounted RF circuitry on the radiation performance.

[0027] Specifically, a polarization-reconfigurable reflection-enhancing metasurface includes multiple radiating elements. The radiating antenna and back-mounted circuit of each radiating element are integrated into a three-dimensional architecture. Each radiating element is a three-layer radiating metal sheet structure. The antenna radiating layer and the RF amplifier circuit layer are separated by a shared metal ground, and the spaces between the metal sheets are filled with a dielectric. The first layer is the antenna radiating layer, which has a radiating patch 1. The second layer is a metal ground, which has a common polarization coupling feed slot 2 and a cross-polarization coupling feed slot 3 for slot coupling feed. The third layer is the RF amplifier circuit layer, which has a back-mounted circuit that feeds the radiating patch 1 of the first layer through electromagnetic coupling.

[0028] Specifically, the radiating patch 1 is a radiating patch for a dual-polarized microstrip antenna, serving both as a receiving antenna for receiving electromagnetic waves and as a transmitting antenna for transmitting reflected electromagnetic waves processed by the radio frequency circuit. The common-polarization coupled feed slot 2 and the cross-polarization coupled feed slot 3 are arranged perpendicularly to each other.

[0029] Specifically, such as Figure 1 , Figure 2 As shown, the RF amplifier circuit layer includes a Wilkinson power divider 4, an RF amplifier 5, an RF switch 6, and a phase shifter 7. The Wilkinson power divider 4 is connected to the common polarization coupled feed slot 2 via a microstrip line, and the output terminal of the Wilkinson power divider 4 is connected to the input terminal of the RF amplifier 5. The RF amplifier 5 is connected to the RF switch 6, and the first output port of the RF switch 6 is connected to the cross polarization coupled feed slot 3, and the second output port is connected to the microstrip circuit of the next radiating unit.

[0030] Specifically, such as Figure 3 As shown, the Wilkinson power divider 4 includes a common polarization input port and two output branches. The Wilkinson power divider 4 is connected to the common polarization coupling feed slot 2 through the common polarization input port. A resistor R18 is provided between the two output branches. One output branch is connected to a capacitor C19, which is connected to the input terminal of the RF amplifier 5. The other output branch is connected to a capacitor C513 through a phase shifter 7 and is connected to the output terminal of the RF switch 6 of the previous radiating unit.

[0031] Specifically, capacitor C4 12 is connected to the power supply port of RF amplifier 5 and the power supply, inductor L1 14 is connected to the output terminal of RF amplifier 5 and the power supply, and the output terminal of RF amplifier 5 is connected to the input terminal of RF switch 6 through capacitor C2 10.

[0032] Specifically, the first output port of the RF switch 6 is connected to the cross-polarization feed port through capacitor C3 11, thereby connecting to the cross-polarization coupling feed slot 3; the second output port of the RF switch 6 is connected to the microstrip circuit of the next radiating unit.

[0033] A polarization-reconfigurable reflection enhancement method is proposed, in which the radiating patch and back-mounted circuit of each radiating element are integrated into a three-dimensional integrated architecture. The RF amplifier, RF switch, Wilkinson power divider and phase shifter are integrated into the antenna back cavity using a multilayer PCB process. The radiating patch serves as both a receiving antenna to receive electromagnetic waves and a transmitting antenna to transmit reflected electromagnetic waves processed by the RF circuit. The back-mounted circuit includes power divider, amplification, switching and phase shifting functions to control the incident electromagnetic waves. The switching between common polarization reflection and cross polarization reflection is achieved by the on / off state of the RF switch.

[0034] Specifically, the isolation between the two output ports of the Wilkinson power divider (isolation of more than 20dB between the two output ports) ensures that the electromagnetic waves received by each radiating unit are radiated out of the next radiating unit and will not be transmitted to other radiating units; the phase shifter is a microstrip delay line that performs phase shifting processing on the signal and can set the phase gradient of the reflecting surface to control the reflection angle of the reflected wave.

[0035] Specifically, the metasurface scattering mechanism is "received and then re-radiated" to change the scattering characteristics of the metasurface array. The electromagnetic wave received by radiating element A is transmitted through a non-reciprocal circuit to its next adjacent radiating element B for re-radiation. The electromagnetic wave received by radiating element B is then transmitted through another non-reciprocal phase shifter to its next radiating element C for re-radiation, and so on for other elements. During cross-polarization reflection, the electromagnetic wave received by radiating element A is transmitted through a non-reciprocal circuit to the cross-polarization port of radiating element A for re-radiation. The electromagnetic wave received by each radiating element is transmitted through a radio frequency circuit to that radiating element for re-radiation, thereby achieving polarization conversion.

[0036] Example

[0037] The radiating antenna and back-mounted circuitry are integrated into a three-dimensional architecture: the RF amplifier, switch, Wilkinson power divider, and phase shifter are integrated into the antenna back cavity using a multi-layer PCB process. The reconfigurable polarized reflection-enhancing metasurface is formed by a series of "radiating patches-Wilkinson power dividers-amplifiers-switches-phase shifters" with a phase gradient. N radiating elements form a 1*N array, and the distance between patches is half the operating wavelength. The radiating patches are for dual-polarized microstrip antennas, which function as both receiving antennas to receive electromagnetic waves and transmitting antennas to transmit reflected electromagnetic waves processed by the RF circuitry.

[0038] The dual-polarized microstrip antenna is a slot-coupled microstrip patch antenna. This type of antenna is simple to fabricate and facilitates the integration of RF circuitry. A metallic ground plane is positioned between two layers of Rogers 4350B dielectric substrates with a dielectric constant of 3.66 and a loss tangent of 0.004. The thicknesses of the upper and lower substrates are h1 = 1.524 mm and h3 = 0.254 mm, respectively. The antenna radiating layer and the RF amplifier circuit layer are separated by a shared metallic ground plane. This advantage significantly reduces the impact of the back-mounted RF circuitry on radiation performance. Coupling slots are created in the metallic ground plane, specifically for common-polarization and cross-polarization coupling. The back cavity circuitry includes power divider, amplifier, switch, and phase-shifting functions to control the incident electromagnetic wave.

[0039] In one embodiment, an RF amplifier is used to amplify the signal, increasing the amplitude of the reflected signal. The RF amplifier circuit uses a Mini-Circuit GVA-81+ amplifier, which requires a voltage supply to operate. =5V.

[0040] In one embodiment, the radio frequency single-pole double-throw switch achieves switching between common-polarization reflection and cross-polarization reflection functional states by controlling the on / off state of the switch; the VSWA2-63DR+ manufactured by Mini-Circuit is used, and this switch requires a voltage supply to operate. =5V. When the control state is 0, RF1-RFCOM is turned on; when the control state is 1, RF2-RFCOM is turned on.

[0041] In one embodiment, the isolation between the two output ports of the Wilkinson power divider ensures that the electromagnetic waves received by unit A are essentially radiated out again from the next unit B, without being transmitted to unit C. The phase shifter is a microstrip delay line that performs phase shifting processing on the signal, allowing the phase gradient of the reflective surface to be set to control the reflection angle of the reflected wave.

[0042] In one embodiment, the circuit further includes two DC blocking capacitors C1, C2, C3, and C5 at the chip input and output, with a capacitance of 2400pF; the transistor's DC bias circuit includes an inductor L1, which is replaced by an inductor with a capacitance of 6.8 nH; and a bypass capacitor C4 with a capacitance of 0.1uF. The Wilkinson power divider consumes 3dB of power across the resistor, thus the power received by the antenna element is lost by 3dB after passing through the power divider. Furthermore, insertion loss exists in the RF circuit, and the scattering electromagnetic surface itself has losses, all of which contribute to the attenuation of reflected energy. By introducing a transistor amplifier to compensate for these power losses, the amplitude of the reflected electromagnetic wave is amplified.

[0043] In one embodiment, the polarization-reconfigurable reflection modulation mechanism is as follows:

[0044] Cross-polarization enhancement mode: Switch 0 state, RF1-RFCOM, the signal received by patch 1 is reflected through the power divider, amplifier, and switch to the cross-polarization feed port of patch 1.

[0045] Common polarization enhancement mode: In switch 1 state, RF2-RFCOM, the received signal passes through the power divider, amplifier, and switch to the common polarization feed port of patch 2 and is then reflected.

[0046] By changing the amplitude and phase of the reflected wave using amplifiers and phase shifters, and selecting the path of the reflected electromagnetic wave using switches, a reconfigurable design for the common polarization and cross polarization scattering characteristics within the entire array band can be achieved.

[0047] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0048] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A polarization-reconfigurable reflection-enhancing metasurface, characterized in that, It includes multiple radiating units, and the radiating antenna and back-mounted circuit of the radiating unit are designed as a three-dimensional integrated architecture. Each radiating unit is specifically a three-layer radiating metal sheet structure. The antenna radiating layer and the RF amplifier circuit layer are separated by a metal ground shared by the two, and the metal sheets are filled with a dielectric. The first layer is the antenna radiating layer, which is provided with a radiating patch (1). The second layer is the metal ground, which is provided with a common polarization coupling feed slot (2) and a cross polarization coupling feed slot (3) for slot coupling feed. The third layer is the RF amplifier circuit layer, which is provided with a back-mounted circuit, which feeds the radiating patch (1) of the first layer through electromagnetic coupling.

2. The polarization-reconfigurable reflection-enhancing metasurface according to claim 1, characterized in that, The radiating patch (1) is a radiating patch for a dual-polarized microstrip antenna, serving as both a receiving antenna for receiving electromagnetic waves and a transmitting antenna for transmitting reflected electromagnetic waves processed by radio frequency circuitry.

3. The polarization-reconfigurable reflection-enhancing metasurface according to claim 1, characterized in that, The common polarization coupled feed slot (2) and the cross polarization coupled feed slot (3) are set perpendicular to each other.

4. The polarization-reconfigurable reflection-enhancing metasurface according to claim 1, characterized in that, The radio frequency amplifier circuit layer includes a Wilkinson power divider (4), a radio frequency amplifier (5), a radio frequency switch (6), and a phase shifter (7); the Wilkinson power divider (4) is connected to the common polarization coupled feed slot (2) via a microstrip line, and the output terminal of the Wilkinson power divider (4) is connected to the input terminal of the radio frequency amplifier (5); the radio frequency amplifier (5) is connected to the radio frequency switch (6), the first output port of the radio frequency switch (6) is connected to the cross polarization coupled feed slot (3), and the second output port is connected to the microstrip circuit of the next radiating unit.

5. The polarization-reconfigurable reflection-enhancing metasurface according to claim 4, characterized in that, The Wilkinson power divider (4) includes a common polarization input port and two output branches. The Wilkinson power divider (4) is connected to the common polarization coupling feed slot (2) through the common polarization input port. A resistor R1 (8) is provided between the two output branches. One output branch is connected to a capacitor C1 (9), which is connected to the input terminal of the RF amplifier (5). The other output branch is connected to a capacitor C5 (13) through a phase shifter (7) and connected to the output terminal of the RF switch (6) of the previous radiating unit.

6. The polarization-reconfigurable reflection-enhancing metasurface according to claim 4, characterized in that, Capacitor C4 (12) is connected to the power supply port of RF amplifier (5) and the power supply, inductor L1 (14) is connected to the output terminal of RF amplifier (5) and the power supply, and the output terminal of RF amplifier (5) is connected to the input terminal of RF switch (6) through capacitor C2 (10).

7. A polarization-reconfigurable reflection-enhancing metasurface according to claim 4, characterized in that, The first output port of the RF switch (6) is connected to the cross-polarization feed port via capacitor C3 (11), thereby connecting to the cross-polarization coupling feed slot (3); the second output port of the RF switch (6) is connected to the microstrip circuit of the next radiating unit.

8. A polarization-reconfigurable reflection enhancement method, said method being based on a polarization-reconfigurable reflection enhancement metasurface according to any one of claims 1-7, characterized in that, Each radiating element's radiating patch and back-mounted circuitry are integrated into a three-dimensional integrated architecture. The RF amplifier, RF switch, Wilkinson power divider, and phase shifter are integrated into the antenna back cavity using a multi-layer PCB process. The radiating patch serves as both a receiving antenna to receive electromagnetic waves and a transmitting antenna to transmit reflected electromagnetic waves processed by the RF circuitry. The back-mounted circuitry includes power divider, amplification, switching, and phase shifting functions to control the incident electromagnetic waves. The switching between common polarization reflection and cross polarization reflection is achieved by adjusting the on / off state of the RF switch.

9. The polarization-reconfigurable reflection enhancement method according to claim 8, characterized in that, The isolation between the two output ports of the Wilkinson power divider ensures that the electromagnetic waves received by each radiating unit are radiated out of the next radiating unit and will not be transmitted to other radiating units. The phase shifter is a microstrip delay line that performs phase shifting processing on the signal and can set the phase gradient of the reflecting surface to control the reflection angle of the reflected wave.

10. The polarization-reconfigurable reflection enhancement method according to claim 8, characterized in that, The metasurface scattering mechanism is "received and then re-radiated," which alters the scattering characteristics of the metasurface array. The electromagnetic wave received by radiating element A is transmitted through a non-reciprocal circuit to its next adjacent radiating element B for re-radiation. Similarly, the electromagnetic wave received by radiating element B is transmitted through another non-reciprocal phase shifter to its next radiating element C for re-radiation, and so on for other elements. During cross-polarization reflection, the electromagnetic wave received by radiating element A is transmitted through a non-reciprocal circuit to the cross-polarization port of radiating element A for re-radiation. The electromagnetic wave received by each radiating element is transmitted through an RF circuit to that radiating element for re-radiation, thus achieving polarization conversion.

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