Plasma screen for electromagnetic pulse protection

Abstract

The invention provides a plasma screen for electromagnetic pulse protection, which adopts a sandwich structure, a first thin film and a second thin film which are positioned on the upper and lower outermost layers adopt flexible dielectric thin films, and a plurality of layers of hollow balls which are closely arranged and have the radius of 0.5-1.5 mm are arranged in the middle. The hollow sphere adopts a non-wave-absorbing dielectric material as a shell, and is filled with easily ionized gas with a certain air pressure. When a strong electromagnetic pulse is incident, gas in the hollow sphere is broken down under the action of a strong electric field to generate plasma, so that the energy of an electromagnetic signal is attenuated. The plasma screen is flexible as a whole, not only can wrap the whole or local gap of equipment, but also can be arranged in front of a radar, so that the plasma screen is a protective device capable of effectively inhibiting forward and backward strong electromagnetic signals.

Description

Technical Field

[0001] The invention relates to the field of communication technology, and in particular to a plasma screen for electromagnetic pulse protection. Background Art

[0002] In the current complex electromagnetic environment, various informationized weapons and equipment are extremely vulnerable to electromagnetic attacks. The strong electromagnetic signals generated by external lightning, electromagnetic pulse bomb explosions, nuclear explosions, and high-power microwave weapons redistribute the electric field inside the electronic system, forming a surge voltage and damaging the electronic system. At the same time, the strong electromagnetic field will pass through the internal circuit of the electronic system, generate induced current, cause electronic signal interference, and damage the system. At present, the electromagnetic pulse protection methods at home and abroad mainly use interface window access technology and electromagnetic shielding equipment. Interface window type electromagnetic pulse attack protection measures can quickly capture electromagnetic pulse impacts, quickly clamp and reduce the electromagnetic pulse energy level, and finally discharge the electromagnetic pulse energy into the earth through grounding technology. Because the time required for its trigger response is more than 100 nanoseconds, it has a good inhibitory effect on lightning pulses lasting tens to hundreds of microseconds; while for nuclear electromagnetic pulses with a pulse width of only a few hundred nanoseconds, its effect is extremely limited. Electromagnetic shielding technology usually uses a shielding cover made of steel or copper plates of a certain thickness, which can provide a high overall shielding effectiveness. However, strong electromagnetic pulses can pass through the metal shielding layer through forward coupling and backward coupling. Forward coupling refers to the use of the antenna of the electronic system to open a high-gain coupling channel for strong electromagnetic pulses, so that the energy of the electromagnetic pulses can directly enter the system, causing damage. Backward coupling refers to the presence of inspection doors and small holes for cables, connectors, switches, etc. in the metal shielding layer. Strong electromagnetic pulses pass through these small holes and couple into the interior of the instrument and equipment, causing serious impact on it.

[0003] Therefore, a protective device is needed that has a fast response time and can effectively suppress strong electromagnetic signals in both the forward and backward directions. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a plasma screen for electromagnetic pulse protection, which can achieve strong attenuation of strong electromagnetic signals, while conventional signals can pass through without attenuation, thus having application potential for electromagnetic protection.

[0005] In order to achieve the above object, the present invention provides a plasma screen for electromagnetic pulse protection, and the technical solution adopted is as follows:

[0006] A plasma screen for electromagnetic pulse protection comprises a first film, a second film and hollow balls, wherein a plurality of the hollow balls are arranged in multiple layers and closely arranged between the first film and the second film;

[0007] The first film and the second film have the same thickness and are both flexible dielectric films;

[0008] The hollow ball comprises an outer shell, the outer shell is made of a non-wave-absorbing medium material, and the interior of the hollow ball is filled with an easily ionizable gas.

[0009] Furthermore, the shell includes an inner layer and an outer layer connected in sequence from the inside to the outside, the inner layer and the outer layer have equal thickness, the inner layer is made of hard ceramic, and the outer layer is made of polyethylene.

[0010] Furthermore, the thickness of the inner layer and the outer layer is 0.1 mm.

[0011] Furthermore, the radius of the hollow sphere is 0.5-1.5 mm.

[0012] Furthermore, the easily ionizable gas is a mixture of Ar and Hg vapor, argon or oxygen.

[0013] Furthermore, the gas pressure in the hollow sphere is 10-100 Torr.

[0014] Furthermore, the flexible dielectric film is made of polyethylene material and has a thickness of 0.1 to 0.3 mm.

[0015] Furthermore, the thickness of the flexible dielectric film is 0.2 mm.

[0016] Furthermore, the radius of the hollow sphere is 1 mm.

[0017] Furthermore, the gas pressure in the hollow sphere is 50 Torr.

[0018] The present invention has at least the following beneficial effects:

[0019] The plasma screen proposed in the present invention is flexible as a whole, and can be used to wrap the equipment as a whole or partially where there are gaps, and can also be placed in front of the radar. When a conventional electromagnetic signal passes through the plasma screen, it will not cause the ionization of the gas in the hollow sphere, and can be transmitted through the plasma screen without loss; when the electric field strength of the electromagnetic signal is greater than the breakdown threshold of the gas in the hollow sphere, the gas in the first layer of hollow spheres in the incoming wave direction is first broken down to form plasma. In the process of plasma formation, part of the energy of the electromagnetic field is absorbed and converted into the ionization energy of the gas, and part is converted into the internal energy of the gas, and the gas temperature rises; at the same time, the formed plasma further absorbs and reflects the subsequent electromagnetic energy. The combined effect of the above three factors causes the electromagnetic signal energy to attenuate. When the intensity of the electromagnetic signal reaching the subsequent layers of hollow spheres is greater than the breakdown threshold of the gas in the hollow sphere, the process that occurs in the first layer occurs again until the intensity of the electromagnetic signal is attenuated to below the breakdown threshold of the gas in the hollow sphere. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for the specific embodiments or the description of the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual scale.

[0021] Figure 1 A schematic structural diagram of a plasma screen for electromagnetic pulse protection according to an embodiment of the present invention is shown.

[0022] Figure 2 A schematic structural diagram of a hollow sphere of a plasma screen for electromagnetic pulse protection according to an embodiment of the present invention is shown.

[0023] Figure 3 The graph shows the relationship between the breakdown time of Ar gas in the hollow spheres of the plasma screen of the present invention and the gas pressure under the action of two intensities of microwave fields according to an embodiment of the present invention.

[0024] Figure 4 The relationship between the breakdown response time of oxygen and Ar in the hollow spheres of the plasma screen according to the embodiment of the present invention and the gas pressure is shown.

[0025] In the figure, 100 is a first film, 200 is a second film, 300 is a hollow sphere, 301 is an outer shell, 3011 is an inner layer, 3012 is an outer layer, and 302 is an easily ionized gas. DETAILED DESCRIPTION

[0026] The following describes the embodiments of the present invention by 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. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0027] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0028] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" 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 an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0030] The embodiment of the present invention provides a plasma screen for electromagnetic pulse protection, such as Figure 1 and Figure 2 As shown, the plasma shield for electromagnetic pulse protection adopts a sandwich structure, the first film 100 and the second film 200 located at the upper and lower outermost layers are flexible dielectric films, and in the middle are multiple layers of closely arranged hollow balls 300 with a radius of about 0.5 to 1.5 mm. The hollow ball 300 includes a shell 301 made of non-absorbent dielectric material, and the hollow ball 300 is filled with an easily ionized gas 302 at a certain pressure.

[0031] The flexible dielectric film is made of polyethylene material and has a thickness of 0.1 to 0.3 mm.

[0032] like Figure 1 As shown, the shell 301 includes an inner layer 3011 and an outer layer 3012, wherein the thickness of the inner layer 3011 and the outer layer 3012 are equal, the material of the inner layer 3011 is ordinary hard ceramic, and the gas is filled in the inner space of the inner layer 3011. The easily ionized gas 302 filled therein is a mixture of Ar and Hg vapor, Ar gas or oxygen. The gas pressure in the hollow ball 300 is about 10 to 100 Torr.

[0033] In a specific embodiment, Figure 1 As shown in Figure 1, the hollow sphere structure used in the plasma screen for strong electromagnetic pulse protection is as follows: Figure 1As shown, the radius of the hollow ball 300 is about 1mm; the shell 301 adopts a double-layer structure, the outer layer 3012 is polyethylene with a thickness of about 0.1mm, and the inner layer 3011 is a hard ceramic with a thickness of about 0.1mm; the easily ionized gas 302 filled in the hollow ball 300 is Ar gas with a pressure of 50Torr. Multiple hollow balls 300 are layered and closely arranged, and each hollow ball 300 is filled and bonded with resin. The first film 100 and the second film located in the upper and lower outermost layers are both flexible polyethylene films with a thickness of about 0.2mm, so as to form a plasma screen with a total thickness of about 1cm, as shown in FIG. Figure 2 shown.

[0034] When a strong electromagnetic pulse is incident, the gas in the hollow sphere is broken down by the strong electric field, generating plasma. Figure 3 The relationship between the breakdown time of Ar gas in the hollow spheres of the plasma screen of the present invention and the gas pressure under the action of microwave fields of two intensities of 2.82 MV / m and 1.41 MV / m is given. Figure 4 The relationship between the breakdown response time of oxygen and Ar and the gas pressure is given, and the corresponding microwave field intensity is 1.41MV / m. During the plasma formation process, part of the electromagnetic field energy is absorbed and converted into the ionization energy of the gas, and part is converted into the internal energy of the gas, and the gas temperature rises; at the same time, the formed plasma further absorbs and reflects the subsequent electromagnetic energy. The combined effect of the above three factors causes the electromagnetic signal energy to attenuate. When the intensity of the electromagnetic signal reaching the subsequent layers of hollow spheres is greater than the breakdown threshold of the gas in the hollow sphere, the process occurring in the first layer occurs again until the intensity of the electromagnetic signal is attenuated to below the breakdown threshold of the gas in the hollow sphere. At the same time, the plasma screen has a fast response time, and can not only wrap the equipment as a whole or locally where there are gaps, but also be placed in front of the radar, so that the strong electromagnetic signals coupled forward and backward can be effectively suppressed.

[0035] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The patent protection scope of the present invention should be defined by the claims.

Claims

1. A plasma screen for electromagnetic pulse protection, characterized in that: It comprises a first film, a second film and hollow balls, wherein a plurality of the hollow balls are arranged in multiple layers and closely arranged between the first film and the second film; The first film and the second film have the same thickness and are both flexible dielectric films; The hollow ball comprises an outer shell, the outer shell is made of a non-wave-absorbing medium material, and the interior of the hollow ball is filled with an easily ionizable gas.

2. The plasma screen for electromagnetic pulse protection according to claim 1, characterized in that: The shell comprises an inner layer and an outer layer which are sequentially connected from the inside to the outside, the inner layer and the outer layer have the same thickness, the inner layer is made of hard ceramic, and the outer layer is made of polyethylene.

3. The plasma screen for electromagnetic pulse protection according to claim 2, characterized in that: The thickness of the inner layer and the outer layer is 0.1 mm.

4. The plasma screen for electromagnetic pulse protection according to claim 1, characterized in that: The radius of the hollow sphere is 0.5-1.5 mm.

5. The plasma screen for electromagnetic pulse protection according to claim 1, characterized in that: The easily ionizable gas is a mixture of Ar and Hg vapor, argon or oxygen.

6. The plasma screen for electromagnetic pulse protection according to claim 1, characterized in that: The gas pressure in the hollow sphere is 10 to 100 Torr.

7. The plasma screen for electromagnetic pulse protection according to claim 1, characterized in that: The flexible dielectric film is made of polyethylene material and has a thickness of 0.1 to 0.3 mm.

8. The plasma shield for electromagnetic pulse protection according to claim 1, characterized in that: The thickness of the flexible dielectric film is 0.2 mm.

9. The plasma screen for electromagnetic pulse protection according to claim 1, characterized in that: The radius of the hollow sphere is 1 mm.

10. The plasma shield for electromagnetic pulse protection according to claim 1, characterized in that: The gas pressure in the hollow sphere is 50 Torr.

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