Total space energy amplification metasurface with dynamically reconfigurable phase

Abstract

The invention discloses a phase dynamic reconfigurable total space energy amplification metasurface which is composed of a plurality of metasurface units arranged in an array mode, and each unit comprises two layers of dielectric plates and four layers of metal. A first slot metal patch and a second slot metal patch which are orthogonally arranged, a PIN diode and a metal microstrip line are loaded on a metal layer on the upper surface of the first dielectric plate, and a metal floor is arranged on the lower surface of the first dielectric plate. The metal layer on the upper surface of the second dielectric plate is used for feeding, and the metal layer on the lower surface of the second dielectric plate is integrated with an amplifying circuit, a power divider circuit, a microstrip line network, a PIN diode and a third slot metal patch which is the same as the second slot metal patch in shape and size. According to the invention, enhancement and adjustment of polarization conversion reflection and transmission amplitude and independent regulation and control of electromagnetic wave phases in reflection and transmission areas can be realized. According to the invention, the amplitude amplification function of electromagnetic energy and the phase regulation function of electromagnetic waves are combined, so that full-space electromagnetic wave energy enhancement and electromagnetic wave 1-bit phase independent regulation can be realized at the same time.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of artificial electromagnetic metamaterials, and particularly relates to a full-space energy amplification super surface with dynamic reconfigurable phase, which can be used for the design of full-space signal energy enhancement. BACKGROUND

[0002] The rapid development of wireless communication technology and the rapid increase of network capacity have put forward higher requirements for electromagnetic propagation environment. Reconfigurable electromagnetic super surface can realize dynamic reshaping of electromagnetic propagation environment by loading adjustable components or variable materials under the action of external excitation, which can dynamically control the amplitude, phase, polarization state and spectral characteristics of electromagnetic waves. This technology not only greatly enriches the manipulation means of electromagnetic waves, but also reshapes the electromagnetic propagation environment in real time and flexibly, providing powerful technical support for coping with complex and variable communication needs. Compared with the traditional reconfigurable electromagnetic surface loaded with lossy components, the integration of amplifier and other gain components can realize the secondary enhancement of electromagnetic wave transmission, which significantly improves the strength and coverage of the signal without increasing the source power. Such super surface avoids the cost increase and safety hazards that may be caused by applying high-power signals, and is expected to bring performance improvement and efficiency optimization to wireless communication, radar detection and electromagnetic stealth.

[0003] According to the different electromagnetic wave control regions, the amplification super surface integrating the amplifier components is mainly divided into two structural types of reflection type and transmission type, and its working mode is based on the action mechanism of "receiving-amplifying-re-radiating". Among them, the reflection type amplification super surface usually loads microwave amplifiers between orthogonal polarization working patch antennas, or loads reflection type amplifiers at the end of the patch, so as to realize the enhancement of the reflected energy of the incident electromagnetic wave; the transmission type amplification super surface cascades amplifiers and transceiving patch antennas on both sides of the super surface, so as to realize the enhancement of the transmitted energy of the incident electromagnetic wave. In the field of wireless communication, it is of great significance to cooperatively control the amplitude and phase of electromagnetic waves in order to further improve the signal coverage and control flexibility, so it is necessary to introduce a phase modulation structure into the above amplification super surface. However, the control region of the present amplification super surface is often limited to a single reflection region or transmission region, and the research on simultaneous reflection and transmission region energy enhancement and independent phase control of the two regions has not been proposed. SUMMARY

[0004] The purpose of the present application is to provide a full-space energy amplification super surface with dynamic reconfigurable phase, which realizes the polarization conversion energy enhancement and 1-bit phase modulation in the reflection and transmission regions respectively.

[0005] Technical Solution: To achieve the above-mentioned objective, this invention provides a phase-dynamically reconfigurable full-space energy amplification metasurface, comprising multiple arrayed metasurface units. Each metasurface unit, from top to bottom, includes a first metal layer, a first dielectric substrate, a second metal layer, a third metal layer, a second dielectric substrate, and a fourth metal layer. The first metal layer is disposed on the upper surface of the first dielectric substrate and includes orthogonally placed first and second slot metal patches, a PIN diode for phase modulation disposed on the second slot metal patch, and a metal microstrip line for current conduction. The second metal layer is a metal ground plane disposed on the lower surface of the first dielectric substrate. The third metal layer is disposed on the upper surface of the second dielectric substrate and includes three metal feed lines for feeding the PIN diode and a fan-shaped stub for suppressing AC signals. The fourth metal layer is disposed on the lower surface of the second dielectric substrate and includes elements for implementing… An amplifier circuit, a power divider circuit, and a microstrip line network for electromagnetic energy transfer, amplification, and splitting; a third slot metal patch with the same shape and size as the second slot metal patch; and a PIN diode disposed on the third slot metal patch for phase control; the first slot metal patch of the first metal layer is connected to the input terminal of the amplifier circuit of the fourth metal layer through metal vias; one output terminal of the power divider circuit is connected to the second slot metal patch of the first metal layer through metal vias, and the other output terminal is connected to one end of the metal microstrip line of the first metal layer through metal vias; the other end of the metal microstrip line is connected to the third slot metal patch of the fourth metal layer through metal vias; three metal feed lines of the third metal layer are respectively connected to the second slot metal patch of the first metal layer, the third slot metal patch of the fourth metal layer, and the input terminal of the power divider circuit through metal vias.

[0006] Preferably, a U-shaped slot is loaded on the first slot metal patch for receiving electromagnetic waves; the second and third slot metal patches are used for radiating electromagnetic waves, and a symmetrical metal patch structure with loaded U-shaped slots is formed by controlling the alternating conduction state of the PIN diodes.

[0007] Preferably, the first slotted metal patch is located in the upper right part of the metasurface unit, the second slotted metal patch is located in the lower left part of the metasurface unit, and the third slotted metal patch is located in the lower right part of the metasurface unit.

[0008] Preferably, the PIN diode in the first metal layer is used to achieve independent phase control of reflection, and the PIN diode in the fourth metal layer is used to achieve independent phase control of transmission.

[0009] Preferably, two PIN diodes are loaded on the second slot metal patch and the third slot metal patch. One end of each PIN diode is interconnected through the inner patch to form a control electrode, and the other end is interconnected through the outer patch to form another control electrode. By loading high and low level signals on the two control electrodes respectively, the alternating conduction selection of the two PIN diodes can be achieved.

[0010] As a preferred embodiment, the power divider circuit of the fourth metal layer adopts a Wilkinson power divider network to realize the incident signal splitting and processing and the simultaneous control of electromagnetic waves in the transmission and reflection regions.

[0011] Preferably, the amplifier circuit of the fourth metal layer is used to amplify the reflected and transmitted input signals, and the amplification factor is dynamically adjusted according to the applied bias voltage.

[0012] Preferably, the PIN diodes in the first and fourth metal layers enable unit control, which is used to control the reflection and transmission phases of each metasurface unit, and the reflection and transmission phases are independently modulated; the amplifier circuit in the fourth metal layer enables board-wide control, which is used to control the reflection and transmission amplitudes of the entire board.

[0013] Preferably, the first dielectric substrate and the second dielectric substrate are connected by a prepreg, and the metal layers are connected by metal vias.

[0014] As a preferred option, the working polarization of the phase-dynamically reconfigurable full-space energy amplification metasurface is linear polarization.

[0015] Beneficial effects: Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1) Experiments show that in the range of 4.9 GHz to 5.1 GHz, the present invention can achieve full-space electromagnetic energy amplification, with a reflection amplification effect of 12 dB and a transmission amplification effect of 11.5 dB.

[0017] 2) While ensuring stable amplification characteristics, this invention integrates 1-bit phase modulation function. Based on structural symmetry, it realizes independent 1-bit phase control of the reflection and transmission regions, that is, it dynamically controls the output electromagnetic wave in two phase states. The unit can realize four phase states.

[0018] 3) The amplitude control range and phase control are independent of each other. By controlling the control voltage of the amplifier circuit and the PIN diode, this invention can achieve a variety of amplitude and phase state combinations, and the amplitude and phase have flexible and reconfigurable characteristics.

[0019] 4) The frequency of this invention is easy to move and has low cost, and it has potential application prospects in wireless communication, space electromagnetic dynamic control and other fields. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the three-dimensional structure of the fully magnified metasurface unit in an embodiment of the present invention.

[0021] Figure 2 The diagrams are schematic diagrams of the planar structure of each metal layer of the full-space magnified metasurface unit in an embodiment of the present invention. (a), (b), (c), and (d) are schematic diagrams of the first metal layer, the second metal layer, the third metal layer, and the fourth metal layer, respectively.

[0022] Figure 3 The diagram shows the connection of the full-space amplification metasurface unit amplifier circuit (a) and the bias voltage change test curve (b) of an embodiment of the present invention.

[0023] Figure 4 The following are simulation results of the full-space magnified metasurface unit in the embodiment of the present invention. (a) and (b) are the simulation curves of the polarization reflection amplitude and reflection phase under four states, and (c) and (d) are the simulation curves of the polarization transmission amplitude and transmission phase. Detailed Implementation

[0024] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The present invention can be implemented in various forms; the accompanying drawings and exemplary descriptions do not limit the present invention to the following embodiments.

[0025] Figure 1 This is a schematic diagram of a unit cell for a phase-dynamically reconfigurable, full-space energy amplification metasurface disclosed in an embodiment of the present invention. The unit cell, from top to bottom, includes a first metal layer, a first dielectric substrate, a second metal layer, a third metal layer, another second dielectric substrate, and a fourth metal layer. The dielectric substrates are connected by prepregs, and the metal layers are connected by metal vias. In this embodiment, both the first and second dielectric substrates are S7136H substrates with a dielectric constant of 3.43, a loss tangent of 0.003, and a thickness of 1.016 mm. All metal layers are copper sheets.

[0026] Figure 2 This is a planar schematic diagram of four metal layers in an embodiment of the present invention. In this embodiment, the first metal layer is disposed on the upper surface of the first dielectric substrate, as shown below. Figure 2 (a) The first metal layer includes orthogonally placed first and second slot metal patches, a PIN diode (1, 2, MACOM, MADP-14020-000907P) disposed on the second slot metal patch, and a metal microstrip line. The first and second slot metal patches are mainly used for electromagnetic wave reception and radiation, the metal microstrip line is used for current conduction, and the PIN diode achieves phase modulation. Figure 2(b) The second metal layer is a complete metal floor that serves as a ground plane shared by AC and DC, and the second metal layer is disposed on the lower surface of the first dielectric plate.

[0027] The third metal layer is disposed on the upper surface of the second dielectric substrate, such as Figure 2 (c) The third metal layer includes three metal feed lines and fan-shaped stubs for feeding the PIN diodes. The fan-shaped stubs suppress AC signals to prevent the feed lines from affecting the cell performance. The fourth metal layer is disposed on the lower surface of the second dielectric substrate, such as... Figure 2 (d) The fourth metal layer integrates multiple core functional units, including an amplifier circuit, a power divider circuit (using a Wilkinson power divider circuit, including a 100-ohm resistor 5), a microstrip line network (including a 15 nH AC-blocking inductor 6), PIN diodes (3, 4, MACOM, MADP-14020-000907P), and a third slot metal patch with the same shape and size as the second slot metal patch. The amplifier circuit and microstrip line are used to transfer and amplify electromagnetic energy, the power divider circuit is used for signal splitting, the radiating patch unit loaded in the slot is used for electromagnetic wave radiation, and the PIN diodes achieve phase modulation.

[0028] like Figure 1 and Figure 2 As shown, in this embodiment, the first slot metal patch of the first metal layer is connected to the input terminal of the amplifier circuit of the fourth metal layer through a metal via. One output terminal of the power divider circuit is connected to the second slot metal patch of the first metal layer through a metal via, and the other output terminal is connected to one end of the metal microstrip line of the first metal layer through a metal via. The other end of the metal microstrip line is then connected to the third slot metal patch of the fourth metal layer through a metal via. The three metal feed lines of the third metal layer are respectively connected to the second slot metal patch of the first metal layer, the third slot metal patch of the fourth metal layer, and the input terminal of the power divider circuit through metal vias.

[0029] This embodiment operates based on the working mechanism of "receiving—amplifying—power divider circuit—reflection / transmission". When an x-polarized electromagnetic wave is incident perpendicularly on the metasurface, the spatial electromagnetic wave is coupled by the first slot metal patch to form a surface current, which flows through the metal vias to the amplifier circuit and the power divider circuit for energy amplification and splitting. One signal is transmitted directly to the second slot metal patch on the surface (with a rectangular slot and PIN diodes (1,2) embedded in the slot) through the microstrip line and metal vias, and is radiated by the second slot metal patch, ultimately achieving enhanced reflection of the incident electromagnetic wave; the other signal is transmitted to the surface metal microstrip line through the microstrip line and metal vias, and then transmitted downwards through the metal vias to the third slot metal patch on the bottom layer (also with a rectangular slot and PIN diodes (3,4) embedded in the slot), and is radiated by the third slot metal patch, ultimately achieving enhanced transmission of the incident electromagnetic wave. By controlling the alternating conduction states of the PIN diodes in the second and third slot metal patches, symmetrical metal patch structures with loaded "U"-shaped slots are formed, providing a structural basis for phase modulation.

[0030] The second and third slot metal patches each have two PIN diodes (a total of four). The PIN diodes are embedded in the patch as switching elements. One end of each PIN diode is interconnected through the inner patch to form a control electrode, and the other end is interconnected through the outer patch to form another control electrode. By applying high and low level signals to the two control electrodes respectively, the alternating conduction selection of the two PIN diodes can be achieved.

[0031] Specifically, in this embodiment, the full-space amplification metasurface utilizes an external DC voltage source and an FPGA control system to control the operating states of the active components mounted on the metasurface. The bias voltage input of the amplification circuit is connected to the DC voltage control terminal via a bottom-layer metal microstrip line to ensure a stable bias voltage input. The ground terminal is directly connected to the metal ground plane via an internal copper-clad metal via to ensure the stability of the amplification circuit. The conduction state of the four PIN diodes is controlled by a control circuit consisting of three feed lines. The four PIN diodes are connected in pairs (1 and 2, 3 and 4), with the connection centers of the two pairs converging and sharing a single feed line. The other ends are connected to the FPGA control system via two 0.3mm wide metal microstrip lines. The control signals output by the FPGA allow for flexible switching between the conduction and cutoff states of the four PIN diodes, thereby switching the operating state of the metasurface unit.

[0032] In this embodiment, the first slot metal patch is 15.3 mm long, 13.3 mm wide, and has a slot length of 8.3 mm; the second slot metal patch is 15.2 mm long, 13.2 mm wide, and has a slot length of 10.4 mm; and the third slot metal patch is 15.2 mm long, 13.2 mm wide, and has a slot length of 10.4 mm.

[0033] In this embodiment, the energy amplification effect depends on the underlying amplification circuit, namely the microwave amplifier. Figure 3 The actual circuit connection of the amplifier circuit in this embodiment is shown. The microwave amplifier is a GVA-123+ (Mini-Circuits) model, and its peripheral circuitry includes a 6.8 nH choke inductor, a 16.5 Ω resistor, a 0.1 uF bypass capacitor, and two 5 pF isolation capacitors. When the bias voltage changes, the forward transmission coefficient of the microwave amplifier circuit changes accordingly. Therefore, the amplification factor of the microwave amplifier circuit can be precisely controlled by adjusting the bias voltage, thereby achieving dynamic adjustment of the full-space amplified metasurface amplitude in this embodiment.

[0034] Simulations were performed in the full-wave simulation software CST Microwave Studio. The elements were subjected to periodic boundary conditions along the x and y axes, and open boundary conditions along the z axis. A field-path co-simulation method was used for simulation verification. Figure 2 In (a), the upper PIN diode (1) is on, and the lower PIN diode (2) is off. Figure 2 In (d), the upper PIN diode (3) is turned on, and the lower PIN diode (4) is turned off, setting it to the "R0" state; when Figure 2 In (a), the upper PIN diode (1) is cut off, and the lower PIN diode (2) is turned on. Figure 2 In (d), the upper PIN diode (3) is turned on, and the lower PIN diode (4) is turned off, setting it to the "R1" state; when Figure 2 In (a), the upper PIN diode (1) is on, and the lower PIN diode (2) is off. Figure 2 In (d), the upper PIN diode (3) is cut off, and the lower PIN diode (4) is turned on, set to the "R2" state; when Figure 2 In (a), the upper PIN diode (1) is cut off, and the lower PIN diode (2) is turned on. Figure 2 In (d), the upper PIN diode (3) is cut off, and the lower PIN diode (4) is turned on, setting it to the "R3" state.

[0035] Depend on Figure 4As shown, for x-polarized incident electromagnetic waves, energy can be amplified in the 4.9 GHz to 5.1 GHz frequency band, with a reflection amplification of 12 dB and a transmission amplification of 11.5 dB. By combining four PIN diode conduction states, independent 1-bit phase modulation can be achieved in both the reflection and transmission regions.

[0036] In summary, the cascaded amplifier circuit and power divider circuit of this invention, by controlling the external bias voltage of the amplifier and the on / off state of the PIN diode, can achieve multi-level amplitude modulation in the reflection and transmission regions and independent 1-bit phase control. This invention designs a 1-bit amplifying electromagnetic metasurface that combines high-efficiency full-space energy enhancement and phase reconfigurability, and is expected to be applied in the field of wireless communication to enhance the quality of full-space communication signals and optimize the communication environment. Furthermore, the adjustable components loaded in this invention have the ability to be combined with spatiotemporal coding technology and can further expand to achieve more diverse electromagnetic functions by leveraging the nonlinear characteristics of the amplifier. Compared with existing work, this invention has significant full-space coverage characteristics, with ideal amplification amplitude in the reflection and transmission regions, and its phase adjustment does not depend on electromagnetic resonance, possessing non-dispersive characteristics. In addition, by combining the operating states of the PIN diode, this invention can also achieve electromagnetic wave modulation in a single reflection or transmission region. By building an external control circuit, this invention can achieve functions such as rapid beamforming and beam deflection, and is expected to play a role in expanding communication range, improving communication quality, electromagnetic deception, and electromagnetic camouflage.

[0037] Furthermore, the amplifier and PIN diode models selected in this invention can be replaced for easy adjustment. The selected microstrip patch antenna structure can also be replaced with other types of electromagnetic radiation units according to actual needs. Simultaneously, the structure possesses frequency-shiftable properties; by changing the parameters and thickness of the dielectric substrate, or the dimensional parameters of each electromagnetic structure, the operating frequency band can be easily adjusted.

[0038] The above description is merely a preferred embodiment of the present invention and should not be construed as limiting the scope of the invention. In other words, any simple equivalent transformations and modifications made based on the claims and description of the present invention should be considered to fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope defined in the claims.

Claims

1. A phase-dynamically reconfigurable, all-space energy-amplifying metasurface, comprising multiple metasurface units arranged in an array, characterized in that, The metasurface unit comprises, from top to bottom, a first metal layer, a first dielectric substrate, a second metal layer, a third metal layer, a second dielectric substrate, and a fourth metal layer; The first metal layer is disposed on the upper surface of the first dielectric substrate and includes a first slot metal patch and a second slot metal patch placed orthogonally, a PIN diode for phase control disposed on the second slot metal patch, and a metal microstrip line for current conduction; the second metal layer is a metal ground plane disposed on the lower surface of the first dielectric substrate. The third metal layer is disposed on the upper surface of the second dielectric substrate, including three metal feed lines for powering the PIN diode and a fan-shaped stub for suppressing AC signals; the fourth metal layer is disposed on the lower surface of the second dielectric substrate, including an amplifier circuit, a power divider circuit and a microstrip line network for realizing electromagnetic energy transfer, amplification and splitting, a third slot metal patch with the same shape and size as the second slot metal patch, and a PIN diode disposed on the third slot metal patch for phase modulation; The first slot metal patch of the first metal layer is connected to the input terminal of the amplifier circuit of the fourth metal layer through a metal via. One output terminal of the power divider circuit is connected to the second slot metal patch of the first metal layer through a metal via, and the other output terminal is connected to one end of the metal microstrip line of the first metal layer through a metal via. The other end of the metal microstrip line is then connected to the third slot metal patch of the fourth metal layer through a metal via. The three metal feed lines of the third metal layer are connected to the second slot metal patch of the first metal layer, the third slot metal patch of the fourth metal layer, and the input terminal of the power divider circuit through metal vias.

2. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The first slotted metal patch is loaded with a U-shaped slot for receiving electromagnetic waves; the second and third slotted metal patches are used for radiating electromagnetic waves. A symmetrical metal patch structure with loaded U-shaped slots is formed by controlling the alternating conduction state of the PIN diodes.

3. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The first slotted metal patch is located in the upper right part of the metasurface unit, the second slotted metal patch is located in the lower left part of the metasurface unit, and the third slotted metal patch is located in the lower right part of the metasurface unit.

4. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The PIN diode in the first metal layer is used to achieve independent phase modulation of reflection, and the PIN diode in the fourth metal layer is used to achieve independent phase modulation of transmission.

5. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The second and third slot metal patches each have two PIN diodes loaded on them. One end of each PIN diode is interconnected through an inner patch to form a control electrode, and the other end is interconnected through an outer patch to form another control electrode. By loading high and low level signals onto the two control electrodes respectively, the alternating conduction selection of the two PIN diodes can be achieved.

6. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The power divider circuit of the fourth metal layer adopts a Wilkinson power divider network to realize the incident signal splitting and processing and the simultaneous control of electromagnetic waves in the transmission and reflection regions.

7. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The amplifier circuit of the fourth metal layer is used to amplify the reflected and transmitted input signals, and the amplification factor is dynamically adjusted according to the applied bias voltage.

8. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The PIN diodes in the first and fourth metal layers enable unit control, which is used to control the reflection and transmission phases of each metasurface unit, and the reflection and transmission phases are independently modulated. The amplifier circuit in the fourth metal layer enables board-wide control, which is used to control the reflection and transmission amplitudes of the entire board.

9. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The first and second dielectric substrates are connected by a prepreg, and the metal layers are connected by metal vias.

10. The phase-dynamically reconfigurable, all-space energy amplification metasurface according to claim 1, characterized in that, The working polarization is linear polarization.

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