阅读说明：本技术 通带状态可调的传输吸波结构 (Transmission wave-absorbing structure with adjustable pass band state ) 是由 周东明 张博汉 于 2021-06-22 设计创作，主要内容包括：本申请涉及一种通带状态可调的传输吸波结构。所述传输吸波结构包括：PIN二极管加载的带通层、PMI泡沫、阻抗元件加载的阻抗层三层依次排列构成；带通层与阻抗层通过PMI泡沫串联,PMI泡沫等效为阻抗变换电路；带通层包括：PIN二极管加载的金属贴片层、介质基板以及金属缝隙层；PIN二极管加载到金属贴片层两相邻贴片之间,且关于金属贴片层的中心旋转对称；采用本方法能够实现通带状态可调。(The application relates to a transmission wave-absorbing structure with an adjustable pass band state. The transmission wave-absorbing structure comprises: the PIN diode load-carrying layer, the PMI foam and the impedance layer loaded by the impedance element are sequentially arranged; the band-pass layer and the impedance layer are connected in series through PMI foam, and the PMI foam is equivalent to an impedance transformation circuit; the band-pass layer includes: the PIN diode comprises a metal patch layer, a dielectric substrate and a metal gap layer which are loaded; the PIN diode is loaded between two adjacent patches on the metal patch layer and is rotationally symmetrical about the center of the metal patch layer; the method can realize the adjustability of the passband state.)

1. A transmission wave-absorbing structure with an adjustable pass band state is characterized by comprising:

the PIN diode loaded band-pass layer, the PMI foam and the impedance layer loaded by the impedance element are sequentially arranged; the belt-through layer and the impedance layer are connected in series through the PMI foam, and the PMI foam is equivalent to an impedance transformation circuit;

the band-pass layer includes: the PIN diode comprises a metal patch layer, a dielectric substrate and a metal gap layer which are loaded; the PIN diode is loaded between two adjacent patches of the metal patch layer and is rotationally symmetrical about the center of the metal patch layer;

when the transmission wave-absorbing structure receives a small signal transmitted in a passband, the PIN diode is in a cut-off state, the bandpass layer is in a resonance state, the impedance of the whole transmission wave-absorbing structure is equivalent to infinity, and the small signal penetrates through the transmission wave-absorbing structure with low loss;

when the transmission wave-absorbing structure receives strong electromagnetic energy, the PIN diode is conducted by the field intensity induced by the metal slit layer, the pass band is closed, and the whole pass band layer has shielding characteristics in the pass band.

2. The transmission absorbing structure of claim 1, wherein the PMI foam is a low dielectric constant and low loss PMI foam.

3. The transmission wave absorbing structure of claim 1, wherein the bandpass layer is designed by an LC series resonance miniaturization structure, the dielectric substrate is a Rogers 4350B dielectric substrate, and the passband of the bandpass layer is equivalent to an inductance-capacitance parallel circuit.

4. The transmission absorbing structure of claim 3, wherein the PIN diodes are symmetrically loaded on the metal patch layer in both vertical and horizontal directions, and the loading period in both directions is the same as the unit structure of the metal patch layer.

5. The transmission absorbing structure of claim 1, wherein the impedance layer is a metal square concentric double ring with impedance element loading.

6. The transmission absorbing structure of claim 5, wherein the size of the outer ring of the metal square concentric double rings is 8.5mm, and the size of the inner ring is 5.5 mm; the impedance value of the impedance element loaded by the outer ring is 300 ohms, the impedance value of the impedance element loaded by the inner ring is 1000 ohms, and the thickness of the dielectric substrate is 0.25 mm.

Technical Field

The application relates to the technical field of power electronics, in particular to a transmission wave-absorbing structure with an adjustable pass band state.

Background

The development of electromagnetic detection technology makes the visual field wider; the strong electromagnetic energy greatly widens the killing range of the information equipment, and seriously threatens the safety of the information equipment.

The existing protective structure design ideas are that when weak field incidence is carried out, surface resistance is large, strong field incidence is carried out, surface resistance change is small, the adopted structure is a single-layer periodic array metal patch structure and has strong electromagnetic radiation protection capability, but due to the influence of PIN diode junction capacitance, the structure similar to an energy selection surface is difficult to expand to a high frequency band, and the structure cannot deal with radio signal detection. The existing wave-absorbing structure mainly comprises three layers, namely an impedance layer, a dielectric layer and a metal layer, and the wave-absorbing structure after optimized design has a wider wave-absorbing band and only a few millimeters in thickness.

Disclosure of Invention

Therefore, it is necessary to provide a transmission wave-absorbing structure with adjustable passband state, which can ensure normal communication and electromagnetic protection at present, in order to solve the above technical problems.

A transmission wave-absorbing structure with an adjustable pass band state comprises:

the PIN diode load-carrying layer, the PMI foam and the impedance layer loaded by the impedance element are sequentially arranged; the belt-through layer and the impedance layer are connected in series through the PMI foam, and the PMI foam is equivalent to an impedance transformation circuit;

the band-pass layer includes: the PIN diode comprises a metal patch layer, a dielectric substrate and a metal gap layer which are loaded; the PIN diode is loaded between two adjacent patches of the metal patch layer and is rotationally symmetrical about the center of the metal patch layer;

when the transmission wave-absorbing structure receives a small signal transmitted in a passband, the PIN diode is in a cut-off state, the bandpass layer is in a resonance state, the impedance of the whole transmission wave-absorbing structure is equivalent to infinity, and the small signal penetrates through the transmission wave-absorbing structure with low loss;

when the transmission wave-absorbing structure receives strong electromagnetic energy, the field intensity induced by the metal slit layer enables the PIN diode to be conducted, the pass band is closed, and the whole pass band layer presents shielding characteristics in the pass band.

In one embodiment, the method further comprises the following steps: the PMI foam is low dielectric constant and low loss PMI foam.

In one embodiment, the method further comprises the following steps: the band-pass layer is designed through an LC series resonance miniaturized structure, the dielectric substrate is a Rogers 4350B dielectric substrate, and the band-pass layer is equivalent to an inductor and capacitor parallel circuit.

In one embodiment, the method further comprises the following steps: the PIN diode is loaded on the metal patch layer in a symmetrical mode in the vertical direction and the horizontal direction, and the loading period in the two directions is the same as the unit structure of the metal patch layer.

In one embodiment, the method further comprises the following steps: the impedance layer is a metal square concentric double ring loaded by impedance elements.

In one embodiment, the method further comprises the following steps: the size of the outer ring of the metal square concentric double ring is 8.5mm, and the size of the inner ring is 5.5 mm; the impedance value of the impedance element loaded by the outer ring is 300 ohms, the impedance value of the impedance element loaded by the inner ring is 1000 ohms, and the basic thickness of the medium is 0.25 mm.

The transmission wave-absorbing structure with the adjustable pass band state adopts a multilayer symmetrical resonance composite structure loaded by lumped elements, comprehensively utilizes the distributed effect of a metal structure and the lumped elements, and realizes the low insertion loss and wide wave-absorbing band characteristic of the pass band of the protective structure. The strong field conduction and weak field cutoff characteristics of the PIN diode are utilized to realize the passband adjustability of the protective structure; the impedance element is used for loading the resonance structure to realize the broadband wave absorbing function, so that the band-on state is adjustable and the broadband wave absorbing function is realized.

Drawings

FIG. 1 is a schematic diagram of a transmission wave-absorbing structure with adjustable pass band states in one embodiment;

FIG. 2 is a transmission performance curve of the transmission-wave absorbing structure with the adjustable pass band state in the on and off states of the PIN diode in one embodiment;

FIG. 3 is a graph of shielding effectiveness for high field radiation of the shielding structure according to one embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In one embodiment, as shown in fig. 1, a method for a transmission wave-absorbing structure with an adjustable pass band state is provided, where the transmission wave-absorbing structure includes: the PIN diode load-carrying layer, the PMI foam and the impedance layer loaded by the impedance element are sequentially arranged; the band-pass layer and the impedance layer are connected in series through PMI foam, and the PMI foam is equivalent to an impedance conversion circuit; the band-pass layer includes: the PIN diode comprises a metal patch layer, a dielectric substrate and a metal gap layer which are loaded; the PIN diode is loaded between two adjacent patches on the metal patch layer and is rotationally symmetrical about the center of the metal patch layer; when the transmission wave-absorbing structure receives a small signal transmitted in a pass band, the PIN diode is in a cut-off state, the pass band layer is in a resonance state, the impedance of the whole transmission wave-absorbing structure is equivalent to infinity, and the small signal penetrates through the transmission wave-absorbing structure with low loss; when the transmission wave-absorbing structure receives strong electromagnetic energy, the PIN diode is conducted by the field intensity induced by the metal gap layer, the pass band is closed, and the whole band-pass layer shows shielding characteristics in the pass band.

In the transmission wave-absorbing structure with the adjustable passband state, the multilayer symmetrical resonance composite structure loaded by the lumped elements is adopted, the distributed effect of the metal structure and the lumped elements is comprehensively utilized, and the low insertion loss and wide wave-absorbing band characteristics of the passband of the protective structure are realized. The strong field conduction and weak field cutoff characteristics of the PIN diode are utilized to realize the passband adjustability of the protective structure; the impedance element is used for loading the resonance structure to realize the broadband wave absorbing function, so that the passband state is adjustable and the broadband wave absorbing function is realized.

In one embodiment, the PMI foam is a low dielectric constant and low loss PMI foam.

In one embodiment, the band-pass layer is designed by an LC series resonance miniaturization structure, the dielectric substrate is a Rogers 4350B dielectric substrate, and the band-pass layer is equivalent to an inductance and capacitance parallel circuit.

In one embodiment, the PIN diode is loaded on the metal patch layer in a symmetrical mode in the vertical direction and the horizontal direction, and the loading period in the two directions is the same as the unit structure of the metal patch layer.

In one embodiment, the resistive layer is a metal square concentric double ring with resistive elements loaded.

In one embodiment, the outer ring size of the metal square concentric double rings is 8.5mm, and the inner ring size is 5.5 mm; the impedance value of the impedance element loaded by the outer ring is 300 ohms, the impedance value of the impedance element loaded by the inner ring is 1000 ohms, and the basic thickness of the medium is 0.25 mm.

In order to verify the technical effect of the invention, the frequency of 1.8GHz is selected as the passband frequency, the corresponding bandpass layer period size is 10mm, and the type of the selected diode is NXP BAP 5102; the basic thickness of the intermediate medium is 0.5 mm. The PMI foam layer is a lightweight, high strength foam having a dielectric constant selected to be about 1.5, a period dimension of 10mm, and a thickness of about 4 mm. The PMI foam layer is arranged between the metal layers and plays a supporting role. The size of the outer ring of the metal square concentric double ring is 8.5mm, and the size of the inner ring is 5.5 mm; the impedance value of the impedance element loaded by the outer ring is 300 ohms, the impedance value of the impedance element loaded by the inner ring is 1000 ohms, and the basic thickness of the medium is 0.25 mm.

On the specific working principle, the working principle of the transmission wave-absorbing structure with the adjustable passband state is as follows: for small signals in a pass band, the PIN diode is in a cut-off state, the pass band layer is in a resonance state at the time, the impedance of the whole structure is equivalent to infinity, and the signals penetrate through the structure with lower loss; when strong electromagnetic energy appears in the passband, the field intensity induced on the metal gap enables the PIN diode to be conducted, the original passband is closed, the whole passband layer shows shielding characteristics in the passband, the shielding efficiency is not less than 10dB, the electromagnetic energy is reflected to be in a space, and the energy in the wave absorbing band is absorbed. No matter strong electromagnetic energy or weak electromagnetic energy, as long as the frequency falls into the wave-absorbing band, the back-end band-pass layer has the characteristic of a metal plate, the electromagnetic energy is completely reflected and reaches the impedance layer through the impedance transformation of the PMI foam layer, and at the moment, because the electromagnetic frequency falls into the resonance frequency of the impedance layer, the electromagnetic wave is completely absorbed by the impedance element. The transmission passband frequency is mainly determined by the passband frequency of the bandpass layer and is simultaneously influenced by the PMI foam, the thinner the PMI foam is, the higher the coupling strength is, the equivalent capacitance is increased, and the passband frequency is shifted downwards.

Simulation was performed using commercial microwave simulation software, and the simulation result is shown in fig. 2.

In the simulation process, the equivalent circuit of the diode in the equivalent cut-off state is a capacitor, and the equivalent circuit in the equivalent cut-off state is a small resistor connected with the inductor in series in the on state. At low field intensity incidence, a transmission pass band is arranged at 1.82GHz, the insertion loss is less than 1dB, and when the diode is conducted (namely when strong electromagnetic energy is incident), the pass band is closed; the absorption band is from 6.9GHz to 22.8GHz regardless of the strength of electromagnetic energy.

It can be seen from fig. 3 that when a small signal is incident, i.e., the diode is in a cut-off state, both simulation and actual measurement have a transmission passband, when a strong electromagnetic energy is incident, i.e., the diode is in a conduction state, the passband is closed, and the shielding effectiveness at the original passband can reach 20 dB. And whether the diode is conducted or not, a wider wave-absorbing band exists. The simulation and actual measurement results of fig. 3 show that the designed transmission wave-absorbing structure with adjustable passband state meets the design requirements.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent application shall be subject to the appended claims.