A high-pass dual-resonance energy selective surface

Abstract

The present invention provides a high-pass dual-resonance energy selective surface, and the energy selective surface unit includes, from top to bottom, an energy selective structure, a dielectric substrate layer 1, and a bottom metal 4. The energy selective structure is located on the upper surface of the dielectric substrate layer 1, and includes two centrally symmetrical dendrite-shaped metal structures and a PIN diode 3 installed at the center of symmetry; the bottom metal is located on the lower surface of the dielectric substrate layer, and includes two completely identical rectangular metal patch structures and a gap therebetween. The present invention designs a high-pass dual-resonance energy selective surface by studying the equivalent circuit of the high-pass dual-resonance energy selective surface. Traditional energy selective surfaces are low-pass surfaces with low-power transmission and high-power reflection, and cannot be applied to reflective surface antennas such as parabolas. The energy selective surface designed by the present invention can provide electromagnetic protection for reflective surface antennas, and has the advantages of strong reflection at low power and high transmission at high power.

Description

Technical Field

[0001] The invention belongs to the technical field of electromagnetic protection, and in particular relates to a high-pass dual-resonance energy selection surface. Background Art

[0002] Entering the 21st century, electronic technology continues to develop, and the trend of informatization, intelligence, integration and unmanned operation is irreversible. Electronic equipment with digital devices and radio frequency devices are widely used in various military fields, becoming the "eyes" and "brains" of military equipment. The electromagnetic offensive and defensive war against these electronic equipment involves almost all fields such as sea, land, air, space, and electromagnetics, and the purpose and method of combat have changed. Therefore, it is of great significance to conduct research on electromagnetic protection and build an indestructible electromagnetic shield for the country.

[0003] At present, the protection against strong electromagnetic pulses can be roughly divided into backdoor protection and frontdoor protection. Among them, backdoor protection mainly focuses on filtering, shielding, and grounding, and the overall technology is relatively mature. The front door refers to the device in the electronic equipment that needs to communicate with the outside world, such as the antenna of various equipment. Front-door protection not only needs to protect against strong electromagnetic pulses, but also needs to be able to meet its needs of receiving or transmitting electromagnetic signals. It is more complex and difficult, and it is easy to become a shortcoming in electromagnetic protection. The technical means of backdoor protection cannot solve the contradiction between these two needs. It is necessary to develop front-door protection means from multiple dimensions such as airspace, frequency domain, time domain, and energy domain.

[0004] In the context of the urgent need for an effective front-door electromagnetic protection method, energy selective surfaces have emerged. Energy selective surfaces are a new type of electromagnetic surface proposed in recent years and are a typical adaptive strong electromagnetic protection device. The X-band broadband energy selective surface proposed in reference [1] has a simple structure and provides electromagnetic protection for high-frequency electronic systems. The ultra-wideband low-profile energy selective surface proposed in reference [2] has a complex structure and uses a large number of PIN diodes, but it achieves protection in the L, C, X, Ku, and K bands. Under the condition of high power density electromagnetic wave incidence, the shielding effectiveness within 0 to 25 GHz is greater than 16 dB. The energy selective surfaces proposed above all change the impedance of the ESS through the PIN diodes on the metal structure when high power density electromagnetic waves are incident, thereby reflecting the high power density electromagnetic waves to achieve protection. These types of energy selective surfaces are called low-pass energy selective surfaces. Parabolic antennas and other reflective antennas are widely used in various fields, while this low-pass energy selective surface with low power transmission and high power reflection cannot be used on reflective antennas. Therefore, designing a high-pass energy selective surface with low-power reflection and high-power reflection to provide electromagnetic protection for reflector antennas is an unresolved problem.

[0005] References [1] Chinese patent CN115566437B, patent name “A X-band broadband energy selective surface”.

[0006] Reference [2] Chinese patent CN116565574A, patent name “A low-profile energy selective surface with ultra-wideband protection”. Summary of the invention

[0007] The purpose of the present invention is to address the above-mentioned electromagnetic protection problem and to propose a low-power reflection and high-power transmission energy selective surface.

[0008] To achieve the above-mentioned purpose of the invention, the technical solution of the present invention is as follows:

[0009] An energy selective surface with low power reflection and high power transmission is characterized in that the energy selective surface unit comprises an energy selective structure, a dielectric base plate 1, and a bottom rectangular metal structure 4 from top to bottom.

[0010] The energy selection structure is located on the upper surface of the dielectric substrate 1. The energy selection structure is composed of a periodic arrangement of energy selection structure units. The energy selection structure unit includes a dendrite-shaped metal structure 2 and a single PIN diode 3 mounted on the dendrite-shaped metal structure 2. The PIN diode 3 is located at the symmetric center of the two dendrite-shaped metal structures 2. The bottom metal 4 is located on the lower surface of the dielectric substrate 1 and includes two rectangular metal structures with a rectangular gap. The long side of the rectangular metal is the same as the length of the metasurface unit, and the short side is related to the width of the rectangular gap.

[0011] As a preferred solution, the periods of the energy selection structural unit and the bottom metal structural unit are both p.

[0012] As a preferred solution, the width of the broadside metal of the dendritic metal structure 2 is ge.

[0013] As a preferred solution, the narrow side metal line width of the dendritic metal structure 2 is gb.

[0014] As a preferred solution, the width of the gap formed by the bottom metal 4 is wf.

[0015] As a preferred solution, the PIN diode 3 is BAR6402 manufactured by Infineon Technologies.

[0016] In terms of working principle:

[0017] The energy selective surface is realized by loading a PIN diode on a metal structure. When the power density is low, the diode is in the cut-off state, which can be approximately equivalent to a small capacitor. When the power density is high, the diode is in the on state, which can be approximately equivalent to a small inductor connected in series with a small resistor. When the working state of the diode changes, it will cause a huge difference in the surface impedance of the energy selective surface, thereby realizing the change of the working state of the energy selective surface. The process of the high-pass energy selective surface changing from a reflective state to a transmissive state is the process of the surface impedance changing from a low resistance state to a high resistance state.

[0018] In order to further explain the principle, an equivalent circuit is established to analyze the high-pass dual-resonance energy selective surface. Figure 1 This is a circuit diagram of the energy selective surface in a reflective state when a low-power electromagnetic wave is incident. It can be seen that when a low-power electromagnetic wave is incident, the PIN diode is equivalent to a capacitor C diode At this time, the capacitor C diode The three components of capacitor C1, capacitor C1 and inductor L1 form a series resonance. By adjusting the values ​​of capacitor C1 and inductor L1, the series resonance point can be placed at the operating frequency. This series resonance can provide extremely high reflectivity at the operating frequency, providing a basis for the normal operation of the reflector antenna. In addition, capacitor C diode , capacitor C1, inductor L1 and capacitor C2 together form a parallel resonance, thereby forming a passband at the high frequency end of the operating frequency.

[0019] Figure 2 This is a circuit diagram of the energy selective surface in the transmission state when a high-power electromagnetic wave is incident. It can be seen that when a high-power electromagnetic wave is incident, the PIN diode is equivalent to an inductor L diode At this time, the inductor L diode The three components of capacitor C1 and inductor L1 form a series resonance. diode The four components of C1, C2 and L1 form a parallel resonance. Due to the change in the working state of the diode, the series resonance point originally at the working frequency moves to a low frequency, and the parallel resonance point originally at the high frequency end of the working frequency also moves to a low frequency, thereby moving the stopband formed by the series resonance out of the working frequency and moving the passband formed by the parallel resonance into the working frequency. And the position of the parallel resonance point can be adjusted only by adjusting C2. Therefore, at this time, the high-power incident wave passes through the surface and is not accepted by the feed source, thereby protecting the subsequent RF system of the feed source.

[0020] Figure 3 and Figure 4It is a physical structural unit established based on the above equivalent circuit. The gap structure formed between the dendritic structures 2 in adjacent units constitutes the capacitor C1 in the equivalent circuit, the fine branches in the dendritic structure 2 constitute the inductor L1 in the equivalent circuit, the diode is loaded at the symmetric center of the dendritic structure 2, and the gap formed by the underlying metal structure 4 constitutes the capacitor C2 in the equivalent circuit.

[0021] The beneficial effects of the present invention are:

[0022] An equivalent circuit of a high-pass energy selective surface unit structure was designed, and based on the constructed equivalent circuit, an energy selective surface with working characteristics completely different from those of traditional energy selective surfaces was designed.

[0023] When low power density is incident, the energy selective surface designed by the present invention generates a stop band in the C band, completely reflecting the electromagnetic waves, thereby ensuring the normal reception and transmission of signals by the protected reflector antenna feed source; when high power density is incident, the energy selective surface designed by the present invention can generate a pass band in the C band, thereby completely transmitting high power electromagnetic waves, and protecting the radio frequency communication system behind the reflector antenna. Compared with traditional energy selective surfaces, the energy selective surface designed by the present invention can provide electromagnetic protection for the reflector antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 An equivalent circuit diagram of the high-pass dual-resonance energy selective surface provided by the present invention in a reflection state under low-power incident conditions;

[0025] Figure 2 An equivalent circuit diagram of the high-pass dual-resonance energy selective surface provided by the present invention in a transmission state under high-power incidence;

[0026] Figure 3 A top view of an energy selection structural unit of a high-pass dual-resonance energy selection surface provided by the present invention;

[0027] Figure 4 A top view of a bottom metal structure unit of a high-pass dual-resonance energy selective surface provided by the present invention;

[0028] Figure 5 A side view of a periodic unit of a high-pass dual-resonance energy selective surface provided by the present invention;

[0029] Figure 6 The frequency response of the high-pass dual-resonance energy selective surface provided by the present invention in two different simulation modes within 4 GHz to 7 GHz;

[0030] Figure 7The relationship between the incident power and the transmission coefficient of the high-pass dual-resonance energy selective surface provided by the present invention at 4, 5, and 6 GHz;

[0031] 1 is a dielectric substrate layer, 2 is a dendritic metal structure, 3 is a PIN diode, and 4 is a bottom rectangular metal structure. DETAILED DESCRIPTION

[0032] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0033] This embodiment provides a high-pass dual-resonance energy selective surface. The energy selective surface unit includes, from top to bottom, an energy selective structure, a dielectric base plate 1, and a bottom rectangular metal structure 4.

[0034] The energy selection structure is located on the upper surface of the dielectric substrate 1. The energy selection structure is composed of a periodic arrangement of energy selection structure units. The energy selection structure unit includes a dendrite metal structure 2 and a single PIN diode 3 installed on the gap. The PIN diode 3 is located at the symmetric center of the two dendrite metal structures 2. The bottom metal 4 is located on the lower surface of the dielectric substrate 1, including two rectangular metal structures with a rectangular gap. The long side of the rectangular metal is the same as the length of the super surface unit, and the short side is related to the width of the rectangular gap. The period of the energy selection structure unit and the bottom metal structure unit is p. The wide side metal width of the dendrite metal structure 2 is ge. The narrow side metal line width of the dendrite metal structure 2 is gb. The gap width formed by the bottom metal 4 is wf. The PIN diode 3 model is BAR6402 of Infineon Technologies.

[0035] Figure 1 The invention discloses an equivalent circuit diagram of a high-pass dual-resonance energy selective surface provided by the present invention after transformation in a reflection state under low-power incidence; the resonance mode corresponding to the circuit is series resonance within the working frequency band, and the corresponding impedance is a relatively small value within the working frequency band.

[0036] Figure 2 The invention discloses an equivalent circuit diagram of a high-pass dual-resonance energy selective surface provided by the present invention after being transformed into a transmission state under high-power incidence; the resonance mode corresponding to the circuit is parallel resonance within the working frequency band, and the corresponding impedance is a relatively large value within the working frequency band.

[0037] Figure 3This is a structural diagram of the high-pass dual-resonance energy selective surface energy selective unit provided in this embodiment; the size of this unit is p=10mm; the wide side metal width of the dendritic metal structure is ge=0.85mm, and the width of ge controls the size of C1 in the equivalent circuit; the narrow side metal width of the dendritic metal structure is gb=0.4mm, and the width of gb controls the size of L1 in the equivalent circuit; the PIN diode is installed in the center of the entire energy selective structure unit.

[0038] Figure 4 This is a structural diagram of the underlying metal unit of the low-power reflective and high-power transmissive energy selective surface provided by the present invention; wherein the width of the gap formed by the underlying metal is wf=1mm, and the size of wf affects the size of C2 in the equivalent circuit.

[0039] Figure 5 This is a side view of this embodiment, which includes, from top to bottom, an energy selection structure, a dielectric base plate, and a bottom rectangular metal structure. The dielectric base plate is made of F4B plate with a dielectric constant of 2.55. The thickness of the F4B base plate is 0.254 mm.

[0040] Figure 6 The response curves of the time domain simulation and frequency domain simulation of this embodiment under low power density or high power density electromagnetic wave incident conditions at 4GHz to 7GHz are shown. Under low power density electromagnetic wave incident conditions, the shielding effectiveness within 4.92GHz to 5.46GHz is greater than 20dB. Under high power density electromagnetic wave incident conditions, the insertion loss within 4.64GHz to 6.12GHz is less than 1dB. In general, this embodiment achieves strong reflection under low power density electromagnetic wave incident conditions and achieves high transmittance passband characteristics under high power density electromagnetic wave incident conditions.

[0041] Figure 7 The relationship between the incident power and the transmission coefficient of the low-power reflective and high-power transmissive energy selective surface provided in this embodiment at 4, 5, and 6 GHz; at 5 GHz, when the incident wave power is lower than 5 dBm, its shielding effectiveness is greater than 20 dB; when the incident wave power is higher than 55 dBm, its insertion loss is less than 1 dB. And as the incident wave power continues to increase, the insertion loss continues to decrease.

[0042] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A high power communication type dual resonance energy selective surface, characterized in that When a high-power electromagnetic wave is incident, it is in a transmission state, and when a low-power electromagnetic wave is incident, it is in a reflection state. The energy selection surface unit comprises, from top to bottom, an energy selection structure, a dielectric base plate (1), and a bottom rectangular metal structure (4); The energy selection structure is located on the upper surface of the dielectric substrate (1), and the energy selection structure is composed of a periodic arrangement of energy selection structure units, wherein the energy selection structure unit comprises a dendrite-shaped metal structure (2) and a single PIN diode (3) mounted on a gap; the PIN diode (3) is located at the symmetry center of the dendrite-shaped metal structure (2); the bottom rectangular metal structure (4) is located on the lower surface of the dielectric substrate (1), and comprises two rectangular metal structures; the long side of the rectangular metal is the same as the length of the super surface unit, and the short side is related to the width of the rectangular gap; When a low-power electromagnetic wave is incident, the dendritic structure is equivalent to a capacitor C diode The three components of the capacitor C1 and the inductor L1 constitute a series resonant circuit, which realizes the reflection state when a low-power electromagnetic wave is incident; When a high-power electromagnetic wave is incident, the dendritic structure is equivalent to an inductor L diode The three components connected in series are capacitor C1, inductor L1, and capacitor C2, which form a parallel resonant circuit. The parallel resonant circuit realizes a transmission state when a high-power electromagnetic wave is incident. Capacitor C1 is equivalent to the gap structure formed between the dendrite structures (2) in adjacent units, L1 is equivalent to the fine branches in the dendrite structure (2), and C diode With L diode The diodes in different states are equivalent, and C2 is equivalent to the gap formed by the bottom rectangular metal structure (4).

2. The high power communication type dual resonance energy selective surface according to claim 1, characterized in that: The periods of the energy selection structural unit and the underlying metal structural unit are both p.

3. The high power communication type dual resonance energy selective surface according to claim 1, characterized in that: The narrow side width of the dendritic metal structure (2) is ge.

4. The high power communication type dual resonance energy selective surface according to claim 1, characterized in that: The broadside width of the dendrite-shaped metal structure (2) is gb.

5. The high power communication type dual resonance energy selective surface according to claim 1, characterized in that: The width of the gap formed by the bottom rectangular metal structure (4) is wf.

6. The high power communication type dual resonance energy selective surface according to claim 1, characterized in that: The PIN diode (3) is BAR6402 manufactured by Infineon Technologies.

Images