Intelligent interference skin based on reconfigurable metasurface

Abstract

The utility model provides an intelligent interference skin based on a reconfigurable metasurface. The intelligent interference skin comprises an incident wave direction sensor, an FPGA controller, a signal generator, a power amplifier and the reconfigurable metasurface which are connected in sequence. The reconfigurable metasurface comprises a dielectric substrate, a plurality of metal patches and diodes, wherein the metal patches are arranged on the dielectric substrate and are of the same structure, and the diodes are arranged on the metal patches respectively. The eight metal patches are divided into two groups, each group comprises a first patch, a second patch, a third patch and a fourth patch, one group is arranged clockwise according to the sequence number, the other group is arranged anticlockwise according to the sequence number, and the two groups of metal patches are connected end to end. And the diodes on the two groups of metal patches are correspondingly conducted and are respectively used for generating adjustable phases of 0 degree, 90 degrees, 180 degrees and 270 degrees. According to the utility model, the anti-reflection of incident electromagnetic waves is realized, and the frequency of echoes is changed, so that the signal received by the own detector can be enhanced without influence, and interference on the enemy detector is realized at the same time.

Description

Technical Field

[0001] The utility model belongs to the technical field of electronic countermeasures, and specifically relates to an intelligent interference skin based on a reconfigurable super surface. Background Art

[0002] In the microwave frequency band, the prior art discloses methods of avoiding detection by enemy detectors by absorption or scattering. However, both methods may have weak echoes that can be detected directly or by enemy detectors in other directions. In recent years, the emergence of metasurfaces has further enriched the means of protecting one's own targets. However, it is not feasible to apply static, time-invariant systems to mobile targets and real-time applications in various changing environments. But the addition of active devices to metasurfaces improves their reconfigurability and intelligence. Traditional methods often focus on performance at vertical incidence, but the performance is significantly reduced at oblique incidence, which is crucial for practical applications. In addition, when faced with challenges such as detection waves of arbitrary polarization and incident direction, Doppler effect and environmental changes, key parameters such as the distance and speed of one's own aircraft may be inadvertently leaked. At the same time, these strategies give priority to avoiding enemy detection, but also pose great challenges to one's own communication and detection. Therefore, it is extremely important to design a spatiotemporal regulated intelligent skin that can both interfere with enemy detection and assist one's own communication and tracking to improve the survivability of one's own aircraft. Utility Model Content

[0003] The purpose of the utility model is to overcome the shortcomings of the above-mentioned prior art and provide an intelligent interference skin based on a reconfigurable metasurface.

[0004] The technical solution adopted by the utility model is:

[0005] An intelligent jamming skin based on a reconfigurable metasurface, characterized in that it comprises: an incident wave direction sensor, an FPGA controller, a signal generator, a power amplifier and a reconfigurable metasurface connected in sequence;

[0006] An incident wave direction sensor is used to sense the incident azimuth and elevation angle of the incident electromagnetic wave;

[0007] An FPGA controller is used to control a signal generator to generate a time-varying voltage signal according to a frequency change of the echo and a phase distribution required for echo beam control;

[0008] A signal generator, used for generating a voltage signal that changes periodically over time;

[0009] A power amplifier, used for amplifying the voltage signal generated by the signal generator;

[0010] A reconfigurable metasurface is used to generate an adjustable phase to achieve dynamic control of the reflection phase when a circularly polarized wave is incident.

[0011] Furthermore, the reconfigurable metasurface includes a dielectric substrate, a plurality of metal patches with the same structure arranged on the dielectric substrate, and a diode respectively arranged on each metal patch.

[0012] Furthermore, the metal patches are arranged into two groups, each group includes patch No. 1, patch No. 2, patch No. 3 and patch No. 4, one group of metal patches are arranged clockwise according to the serial number, and the other group of metal patches are arranged counterclockwise according to the serial number, and the two groups of metal patches are connected end to end.

[0013] Furthermore, the diodes on patch No. 1, patch No. 2, patch No. 3, and patch No. 4 in the two groups of metal patches are turned on correspondingly, and are used to generate adjustable phases of 0°, 90°, 180°, and 270°, respectively.

[0014] Beneficial effects of the utility model:

[0015] First, the utility model only uses diodes and other devices, so the cost is low and it is easy to integrate and mass produce;

[0016] Second, the reconfigurable metasurface in the utility model is composed of metal patches loaded with diodes. By controlling the conduction of diodes in different directions, the dynamic rotation of the surface current can be realized, thereby realizing an adjustable PB phase. Based on the reconfigurable PB phase, there is no dispersion and the bandwidth is wider, which can achieve more efficient beam control, and at the same time greatly reduces the difficulty of designing the time modulation sequence required for anti-reflection and frequency change;

[0017] Third, the utility model obtains the incident azimuth and pitch angle through the incident wave direction sensor, and calculates the phase distribution required for anti-reflection through the FPGA controller, thereby realizing anti-reflection, and realizes the echo frequency change through the time modulation formed by the rapid switching of the diode state, and finally realizes the change of anti-reflection and echo frequency, so as to interfere with enemy detectors and assist one's own communication and tracking at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a schematic diagram of the structure of the utility model;

[0020] Figure 2 (a) is a schematic diagram of the structure of the reconfigurable metasurface of the present invention; Figure 2 (b) is the reflection amplitude of the unit when the circularly polarized wave is incident obliquely at different angles; Figure 2 (c) is the reflection amplitude of the unit when the circularly polarized wave is incident vertically; Figure 2 (d) is the reflection phase of the unit when the circularly polarized wave is incident vertically;

[0021] Figure 3 (a)-(d) are respectively the amplitude and phase of the reconfigurable metasurface of the utility model under vertical incidence of y-polarized electromagnetic waves, reflected as y-polarized and x-polarized in four states;

[0022] Figure 4 is the equivalent phase of the utility model under 8 time coding sequences, where 00, 01, 10 and 11 represent PB phases of 0°, 90°, 180° and 270° respectively;

[0023] Figure 5 Two phase coding distributions designed for the utility model, wherein coding 1 and coding 2 correspond to electromagnetic waves with incident directions of (10°, 90°) and (-32°, 90°) respectively;

[0024] Figure 6 (a) is the reflected spectrum when the incident angle is (10°, 90°); Figure 6 (b) is the reflected spectrum when the incident angle is (-32°, 90°); Figure 6 (c) is the spectrum of the first-order harmonic at different modulation speeds;

[0025] Figure 7 (a)-(b) are the anti-reflection effects achieved by the two codes designed in the utility model when responding to the incident y-polarized electromagnetic wave; Figure 7 (c) is the frequency variation effect of the utility model;

[0026] Among them, 1-incident wave direction sensor, 2-reconfigurable metasurface, 3-FPGA controller, 4-signal generator, 5-power amplifier, 21-dielectric substrate, 22-metal patch, 23-diode, 221-patch No. 1, 222-patch No. 2, 223-patch No. 3, 224-patch No. 4. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present utility model clearer, the technical solution in the embodiments of the present utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the present utility model.

[0028] In the description of the present invention, it should be understood that the terms "length direction", "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] Please refer to the following Figure 1-7 , the complete technical scheme and embodiments of this application are explained in detail.

[0031] The utility model provides an intelligent interference skin based on a reconfigurable metasurface, comprising an incident wave direction sensor 1, an FPGA controller 3, a signal generator 4, a power amplifier 5 and a reconfigurable metasurface 2 connected in sequence;

[0032] The incident wave direction sensor 1 is used to sense the incident direction of the incident electromagnetic wave, mainly including the incident azimuth angle and the pitch angle;

[0033] FPGA controller 3, used for calculating the echo frequency change and the phase distribution required for echo beam control according to the obtained incident direction, and controlling the signal generator to generate a time-varying voltage signal according to the echo frequency change and the required phase distribution;

[0034] A signal generator 4, used to generate a voltage signal that changes periodically over time;

[0035] A power amplifier 5, used to amplify the voltage signal generated by the signal generator and send the voltage signal to the reconfigurable metasurface;

[0036] The reconfigurable metasurface 2 is composed of an isotropic structure (metal patch) loaded with switching diodes. By controlling the conduction of diodes in different directions, the dynamic rotation of the surface current can be achieved, generating an adjustable PB phase as the basic coding state for time coding. Based on the adjustable PB phase, the dynamic regulation of the reflection phase when a circularly polarized wave is incident can be achieved.

[0037] Combination Figure 2 It can be seen from a that the reconfigurable metasurface 2 includes a dielectric substrate 21, a plurality of metal patches 22 with the same structure, and a diode 23. The metal patches 22 are evenly arranged on the dielectric substrate 21, and each metal patch 22 is provided with a diode 23.

[0038] Preferably, there are 8 metal patches 22, and 4 patches form a group, with a total of two groups, each group including patch No. 1 221, patch No. 222, patch No. 3 223 and patch No. 4 224, one group of metal patches 22 is arranged clockwise according to the patch number, and the other group of metal patches 22 is arranged counterclockwise according to the patch number, the two groups of metal patches 22 are connected end to end to form a circle, and patch No. 1 221, patch No. 222, patch No. 3 223 and patch No. 4 224 in one group are respectively opposite to patch No. 1 221, patch No. 222, patch No. 3 223 and patch No. 4 224 in the other group.

[0039] In addition, the diode on one patch No. 1 and the diode on another patch No. 1 are turned on to generate a 0° adjustable phase, the diode on patch No. 2 and the diode on another patch No. 2 are turned on to generate a 90° adjustable phase, the diode on patch No. 3 and the diode on another patch No. 3 are turned on to generate a 180° adjustable phase, and the diode on patch No. 4 and the diode on another patch No. 4 are turned on to generate a 270° adjustable phase.

[0040] Working principle: The incident wave direction sensor 1 obtains the incident direction of the incident electromagnetic wave and sends it to the FPGA controller 3. Then, when the FPGA controller 3 calculates the echo frequency change and the back reflection (the incident wave is reflected along the incident direction, i.e., the echo beam is regulated) according to the incident direction, the phase distribution required by the reconstructed metasurface can be reconstructed, thereby controlling the signal generator 4 to generate a control voltage that changes periodically with time. After amplification by the power amplifier 5, the diode 23 on the reconfigurable metasurface 2 is controlled to be turned on and off periodically to obtain the required adjustable phase, thereby realizing arbitrary regulation of the echo beam and the echo frequency. For the friendly detector, the change of the echo frequency is known, and the back reflection can better realize tracking and communication; for the enemy detector, since the change of the echo frequency is unknown and there is a polarization mismatch, it effectively makes it obtain the wrong speed and distance information of the friendly aircraft.

[0041] Example

[0042] In order to verify the performance of the utility model, the following simulation experiment was carried out.

[0043] 1. Simulation conditions

[0044] In this embodiment, the entire reconfigurable metasurface 2 is set as periodic boundary conditions in the x and y directions, and a plane wave is incident along the -z direction. The electromagnetic simulation software is used to simulate the reflection amplitude and phase of the reconfigurable metasurface 2 in different states of this embodiment. After obtaining the basic performance of the unit simulation, the equivalent phase and amplitude under the time series are simulated using MATLAB software. Finally, the performance of anti-reflection and changing echo frequency is tested using a spectrum analyzer.

[0045] 2. Simulation content and results

[0046] The following two simulation and test experiments are carried out respectively:

[0047] (1) Simulation 1

[0048] When the 4.2-6GHz simulated circularly polarized wave is incident in the C band, the performance of the metasurface 2 can be reconstructed in this example. When the diodes in different directions are turned on separately, the reflection amplitude is 1 when the circularly polarized wave is incident, and the phase is 0°, 90°, 180°, and 270°, such as Figure 2 As shown in (d), it can be seen that when time series modulation is adopted, the reconfigurable metasurface corresponds to four phase states (0°, 90°, 180°, 270°); the equivalent reflection phase obtained by the time coding sequence is shown in Figure 4 shown.

[0049] (2) Simulation 2

[0050] When the y-polarized wave is simulated at 4.2-6 GHz in the C band, the performance of the metasurface unit can be reconstructed in this example. When only one direction (i.e., a group of patches) of diodes are turned on individually, part of the y-polarized wave is converted into an x-polarized wave, and the echo energy is greatly weakened. Figure 3 As shown; when linear polarization is incident, the reconfigurable metasurface unit also has four basic states.

[0051] (3) Test 1

[0052] The phase distributions corresponding to two incident directions (10°, 90°) and (-32°, 90°) are designed, as shown in Figure 5 As shown in the figure, when a circularly polarized wave is incident, the echo is along the incident direction and the echo frequency changes with time. Therefore, when the friendly detector uses a circularly polarized wave, the received signal can be enhanced, while the changing frequency of the enemy detector causes it to obtain incorrect distance and speed information, such as Figure 6 shown.

[0053] (4) Test 2

[0054] Design the phase distributions corresponding to the two incident directions (10°, 90°) and (-32°, 90°), as follows: Figure 5As shown in Code 1 and Code 2 in ; when the y-polarized wave is incident, the echo is along the incident direction but the energy is greatly weakened and the echo frequency changes with time; therefore, the echo received by the enemy detector is very weak, and due to the changing frequency, it obtains incorrect distance and speed information, such as Figure 7 shown.

[0055] The simulation results show that the intelligent skin proposed in the utility model realizes the anti-reflection of the incident electromagnetic wave and changes the frequency of the echo; since the frequency change is known to the friendly party, the signal received by the friendly party's detector can be enhanced without any impact; for the enemy detector, the frequency change and polarization mismatch can cause it to obtain wrong speed and distance information, thereby achieving interference.

[0056] It should be clear that the above detailed description of the embodiments of the utility model provided in the accompanying drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

Claims

1. A smart interference skin based on a reconfigurable metasurface, characterized in that: include: An incident wave direction sensor (1), an FPGA controller (3), a signal generator (4), a power amplifier (5), and a reconfigurable metasurface (2) connected in sequence; An incident wave direction sensor (1) for sensing the incident azimuth and elevation angle of the incident electromagnetic wave; An FPGA controller (3) is used to control a signal generator (4) to generate a time-varying voltage signal according to a frequency change of the echo and a phase distribution required for echo beam control; A signal generator (4), used for generating a voltage signal that changes periodically over time; A power amplifier (5), used for amplifying the voltage signal generated by the signal generator; A reconfigurable metasurface (2) is used to generate an adjustable phase so as to achieve dynamic control of the reflection phase when a circularly polarized wave is incident.

2. According to claim 1, the intelligent interference skin based on reconfigurable metasurface is characterized in that: The reconfigurable metasurface (2) comprises a dielectric substrate (21), a plurality of metal patches (22) with the same structure arranged on the dielectric substrate (21), and a diode (23) respectively arranged on each metal patch (22).

3. According to claim 2, the intelligent interference skin based on reconfigurable metasurface is characterized in that: The metal patches (22) are arranged in two groups, each group comprising a No. 1 patch (221), a No. 2 patch (222), a No. 3 patch (223) and a No. 4 patch (224), wherein one group of metal patches (22) is arranged clockwise according to the serial number, and the other group of metal patches (22) is arranged counterclockwise according to the serial number, and the two groups of metal patches (22) are connected end to end.

4. According to claim 3, the intelligent interference skin based on reconfigurable metasurface is characterized in that: The diodes (23) on patch No. 1 (221), patch No. 2 (222), patch No. 3 (223), and patch No. 4 (224) in the two groups of metal patches (22) are turned on correspondingly, and are used to generate adjustable phases of 0°, 90°, 180°, and 270°, respectively.

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