阅读说明：本技术 一种超宽频带强电磁场防护装置 (Ultra-wideband strong electromagnetic field protection device ) 是由 张文梅 秦冬梅 张丽红 杨荣草 贾鹤萍 梁美彦 于 2019-10-27 设计创作，主要内容包括：一种超宽频带强电磁场防护装置,涉及空间强电磁场防护领域,它包括有源频率选择表面、两层介质基板、带通频率选择表面；其中,有源频率选择表面印制在上层介质基板的上表面；带通频率选择表面印制在下层介质基板的下表面；两层介质基板中间是空气层；有源频率选择表面的单元结构为刻蚀了方环形缝隙和四条圆弧形缝隙的金属贴片,方环形缝隙的四条边上跨接有开关二极管,圆弧形缝隙上加载了三条等距排列的矩形贴片；带通频率选择表面的单元结构与有源频率选择表面相似,只是方环形缝隙和圆弧形缝隙尺寸与后者不同。本发明解决了目前防护装置防护带宽有限,造成大功率信号泄露的问题。(An ultra-wide band strong electromagnetic field protection device relates to the field of space strong electromagnetic field protection, and comprises an active frequency selection surface, two layers of dielectric substrates and a band-pass frequency selection surface; the active frequency selection surface is printed on the upper surface of the upper-layer dielectric substrate; the band-pass frequency selection surface is printed on the lower surface of the lower-layer dielectric substrate; an air layer is arranged between the two dielectric substrates; the unit structure of the active frequency selection surface is a metal patch etched with a square annular gap and four arc-shaped gaps, four edges of the square annular gap are connected with switching diodes in a spanning mode, and three rectangular patches which are arranged at equal intervals are loaded on the arc-shaped gaps; the unit structure of the band-pass frequency selective surface is similar to that of the active frequency selective surface except that the dimensions of the square annular gap and the circular arc gap are different from those of the latter. The invention solves the problem of high-power signal leakage caused by limited protection bandwidth of the conventional protection device.)

1. An ultra-wide band strong electromagnetic field protection device is characterized in that: the device comprises an active frequency selection surface (1), an upper dielectric substrate (2), a lower dielectric substrate (3) and a band-pass frequency selection surface (4);

the active frequency selective surface (1) is printed on the upper surface of the upper-layer dielectric substrate (2); the band-pass frequency selection surface (4) is printed on the lower surface of the lower-layer dielectric substrate (3); an air layer is arranged between the upper dielectric substrate (2) and the lower dielectric substrate (3); the axis of the active frequency selection surface (1), the axis of the upper dielectric substrate (2), the axis of the lower dielectric substrate (3) and the axis of the band-pass frequency selection surface (4) are coincident;

the active frequency selection surface (1) is composed of M multiplied by M units, each unit is a square metal patch (5), square annular gaps (6) are etched on the square metal patches (5), and PIN diodes (7) are connected on four gaps of the square annular gaps (6) in a crossing mode; an arc-shaped gap (9) with the radius of R is etched on an inner patch (8) surrounded by the square annular gap (6), and three rectangular patches (10) which are arranged at equal intervals are loaded on the arc-shaped gap (9);

the band-pass frequency selection surface (4) is composed of M multiplied by M units, each unit is a square metal patch (11), and a square annular gap (12) is etched on each square metal patch (11); an arc-shaped slit (14) with the radius of S is etched on an inner patch (13) surrounded by the square annular slit (12), and three rectangular patches (15) which are arranged at equal intervals are loaded on the arc-shaped slit (14).

2. Ultra-wide band strong currentMethod for protection against magnetic fields, a method for protection against high electromagnetic fields in ultra-wide bands, characterized by the fact that the power density at the location of the protection device according to claim 1 is such that, when low-power signals are incident<17W/m ²The induced voltage is less than the threshold voltage, the diode is cut off, and the resonant frequencies of the active frequency selective surface and the band-pass frequency selective surface are all f ₁The active frequency selective surface and the band-pass frequency selective surface have the same frequency as the operating frequency f ₁All signals of (2) are represented as transmission signals and the working frequency is f ₁Can transmit the electromagnetic wave; power density when incident on a guard according to claim 1>17W/m ²When the induced voltage is greater than the conduction voltage, the diode is conducted, and the resonant frequency of the active frequency selective surface is shifted to f ₂When the division frequency is f ₂The external high-power microwaves are reflected by the active frequency selective surface, and only the frequency is f ₂The high power microwave can be transmitted continuously through the active frequency selective surface, and the resonant frequency is f ₁The band-pass frequency selective surface has a frequency of f ₂The high-power microwave signal shows strong reflection, and ultra-wideband protection of the high-power signal is realized.

Technical Field

The invention is used for the field of space strong electromagnetic field protection, and particularly relates to an ultra-wideband strong electromagnetic field protection device.

Background

As High Power Microwave Weapons (HPMW) technology has matured, the strong electromagnetic pulses generated by the HPMW may couple through an antenna into electronic systems such as radar, communications, etc., causing irreversible damage to the electronics. Therefore, the research on the protection strategy of the electronic equipment under the condition of a strong field has very important significance.

In general, there are two main measures for spatial protection of High Power Microwaves (HPM), the first is an active frequency selective surface, which is composed of a frequency selective surface, a semiconductor device having a switching characteristic, and a bias circuit. By controlling the on and off of the semiconductor device, the active frequency selective surface can realize the compatibility of receiving and sending working signals and in-band HPM protection (S. Monni et al., "Limiting frequency selective surface," in Proc. Eur. micro. Conf., Oct. 2009, pp. 606-609.). But high-power microwaves in certain specific frequency bands outside the passband can still pass through the active frequency selective surface, so that the radio frequency front end sensitive module is damaged. The second is an Energy Selective Surface (ESS), which is typically composed of a metal grid and a semiconductor device. The ESS can adaptively perform HPM protection according to the magnitude of incident wave power value (C.Yang et al, 'A novel method of energy selective surface for adaptive HPM/EMPprotection', IEEE antenna Wireless processing, Lett., vol. 12, pp. 112, 115, 2013). However, due to the limitation of processing precision, the protection range of the energy selection surface is generally 0-3GHz at present, and the protection performance on high-frequency HPM is limited.

In view of the problems that the active frequency selective surface can only protect the in-band HPM and the energy selective surface has no protection effect on the high frequency HPM signal. The invention provides a protection device with ultra-wide band strong field protection capability.

Disclosure of Invention

The invention provides a protection device for realizing ultra wide band high field protection by adopting a method of cascading a band-pass frequency selection surface and an active frequency selection surface, aiming at solving the problem of HPM leakage caused by limited protection bandwidth of the active frequency selection surface and the energy selection surface at present.

The invention is realized by adopting the following technical scheme:

an ultra-wideband strong electromagnetic field protection device sequentially comprises an active frequency selection surface, an upper dielectric substrate, a lower dielectric substrate and a band-pass frequency selection surface from top to bottom;

the active frequency selective surface is printed on the upper surface of the upper dielectric substrate; the band-pass frequency selection surface is printed on the lower surface of the lower-layer dielectric substrate; an air layer is arranged between the upper dielectric substrate and the lower dielectric substrate; the axis of the active frequency selection surface, the axis of the upper layer dielectric substrate, the axis of the lower layer dielectric substrate and the axis of the band-pass frequency selection surface are coincided;

the active frequency selection surface is composed of M multiplied by M units, each unit is a square metal patch, square annular gaps are etched on the square metal patches, and PIN diodes are connected to four gaps of the square annular gaps in a crossing mode; an arc-shaped gap with the radius of R is etched on the internal patch surrounded by the square annular gap, and three rectangular patches which are arranged at equal intervals are loaded on the arc-shaped gap;

the band-pass frequency selection surface is composed of M multiplied by M units, each unit is a square metal patch, and a square annular gap is etched on each square metal patch; an arc-shaped gap with the radius of S is etched on the internal patch surrounded by the square annular gap, and three rectangular patches which are arranged at equal intervals are loaded on the arc-shaped gap;

the transmission characteristic of the high-field protection device is controlled by the power of an incident signal; when low power signal is incident (power density at guard sample)<17W/m ²) Since the induced voltage is less than the threshold voltage, the diode is turned off. At this time, the resonance frequencies of both the active frequency selective surface and the band-pass frequency selective surface f ₁Both for an operating frequency of f ₁All appear to be transmissive, so the operating frequency is f ₁Can be transmitted. At HPM incidence (power density at guard sample)>17W/m ²) Since the induced voltage is greater than the turn-on voltage, the diode turns on and the resonant frequency of the active frequency selective surface shifts to f ₂When the division frequency is f ₂The outer HPMs are all reflected by the active frequency selective surface, only at a frequency of f ₂Can continue transmission through the active frequency selective surface, and the resonant frequency is f ₁The band-pass frequency selective surface has a frequency of f ₂The HPM signal shows strong reflection, so that the strong field protection device can realize ultra-wide band protection on high-power signals.

Ultra-wideband in the present invention means that the relative bandwidth exceeds 100%. High power microwave refers to a microwave signal generated by a pulsed weapon.

Compared with the existing active frequency selection surface, the method of the invention not only broadens the working bandwidth of the active frequency selection surface, but also realizes the full-band protection of the HPM outside the in-band by using the method of cascading the band-pass frequency selection surface and the active frequency selection surface, obviously improves the peak leakage problem and improves the protection effect; meanwhile, the arc-shaped gap is etched on the central patch of the square annular gap unit, so that the adjustability of the resonant frequency of the unit structure is increased; the realized high-field protection device can transmit normal communication signals of 3.28-3.92GHz in a pass band, the relative bandwidth reaches 17.78%, the insertion loss is lower than 0.72dB, high-power microwaves of 0-20GHz are prevented from entering a system, and the shielding effectiveness is greater than 13 dB.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Fig. 2 is a schematic diagram of an implementation process of an active frequency selective surface unit structure.

Wherein, a is a square annular gap etched on the square metal patch 5; b is that a circular arc-shaped gap 9 with the radius of R is etched on the inner patch 8 surrounded by the square annular gap; c, three rectangular patches 10 which are arranged at equal intervals are loaded on the circular arc-shaped gap 9; d, PIN diodes are bridged on the four gaps of the square annular gap;

fig. 3 is a schematic diagram of a band-pass frequency selective surface unit structure implementation process.

In the figure, e is a square annular gap 12 etched on a square metal patch 11; f is an arc-shaped gap 14 with the radius of R etched on the inner patch 13 surrounded by the square annular gap; g is three rectangular patches 15 which are arranged at equal intervals are loaded on the arc-shaped gap 9;

FIG. 4 shows S under low power signal incident conditions according to the present invention ₂₁Schematic representation.

FIG. 5 shows S under high power signal incident condition according to the present invention ₂₁Schematic representation.

Fig. 6 is a schematic diagram of the transient response of the present invention under low power signal incidence conditions.

Fig. 7 is a schematic diagram of the transient response of the present invention under high power signal incident conditions.

FIG. 8 is a graph of the transmission field strength of the present invention at different incident field strengths.

Fig. 9 is a graph showing the shielding effectiveness of the present invention at different incident field strengths.

In the figure: 1-active frequency selection surface, 2-upper dielectric substrate, 3-lower dielectric substrate, 4-band-pass frequency selection surface, 5-square metal patch, 6-square annular gap, 7-PIN diode, 8-internal patch, 9-arc gap, 10-rectangular patch, 11-square metal patch, 12-square annular gap, 13-internal patch, 14-arc gap, and 15-rectangular patch.

Detailed Description

A device capable of realizing strong electromagnetic field protection in an ultra-wide band comprises an active frequency selection surface 1, an upper dielectric substrate 2, a lower dielectric substrate 3 and a band-pass frequency selection surface 4;

the active frequency selective surface 1 is printed on the upper surface of an upper-layer dielectric substrate 2; the band-pass frequency selection surface 4 is printed on the lower surface of the lower-layer dielectric substrate 3; an air layer is arranged between the upper dielectric substrate 2 and the lower dielectric substrate 3; the axis of the active frequency selection surface 1, the axis of the upper dielectric substrate 2, the axis of the lower dielectric substrate 3 and the axis of the band-pass frequency selection surface 4 are coincident;

the active frequency selection surface 1 is composed of M multiplied by M units, each unit is a square metal patch 5, square annular gaps 6 are etched on the square metal patches 5, and PIN diodes 7 are connected to four gaps of the square annular gaps 6 in a crossing mode; an arc-shaped gap 9 with the radius of R is etched on an inner patch 8 surrounded by the square annular gap 6, and three rectangular patches 10 which are arranged at equal intervals are loaded on the arc-shaped gap 9;

the band-pass frequency selection surface 4 is composed of M × M units, each unit is a square metal patch 11, and a square annular gap 12 is etched on each square metal patch 11; an arc-shaped slot 14 with the radius of S is etched on an inner patch 13 surrounded by the square annular slot 12, and three rectangular patches 15 which are arranged at equal intervals are loaded on the arc-shaped slot 14;