KR20130048029A - Low-observable radome and vehicle having the same - Google Patents

Abstract

PURPOSE: A low-observable radome and a moving body including the same are provided to implement stable operation by having low heat transfer coefficient. CONSTITUTION: A plurality of bodies(110) cover an antenna device(160). A support bar(140) arranges the antenna device. A support axis supports one of the bodies. A frequency selective transmissive layer transmits a frequency. A first cover layer surrounds the circumference of the body.

Description

Low-detection Radome and Vehicle having the same

Embodiments of the present invention relate to a low-detection radom and a moving body having the same, which reduces the possibility of being detected by the other party's radar. More specifically, the present invention relates to a low-detection radome reinforced with aramid fiber which improves the shock characteristics and vibration absorption of the radome and at the same time satisfies the electromagnetic wave transmission function.

Radar (Radar detecting and ranging) is a device for detecting and measuring the position and distance of objects using electromagnetic waves of 3 MHz to 300 GHz.

The technology of detecting the other party using the electromagnetic wave of the radar is called detection technology, while the technology of preventing any object from being detected by the other party's radar is called stealth technology.

In the modern warfare of electronic warfare based on high-performance electronic equipment, stealth technology that can perform the mission without being detected by the opponent's radar is an important strategic factor that can determine the victory or defeat of the war. For this reason, research and development of electromagnetic wave absorption technology are actively progressing.

Such stealth technology is recognized as an important technical field that determines the survivability of the weapon system in modern warfare. Countries around the world have done much research to apply this technology to weapon systems such as aircraft, ships, and missiles. have.

Reducing radar cross sections (RCS) is key to providing stealth capabilities in weapons systems such as aircraft and ships.

RCS is the area of weapon system detected by radar in terms of area. There are two ways to reduce RCS of weapon system. One is to absorb electromagnetic waves incident on the fuselage of the weapon system, and the other is to selectively transmit and reflect electromagnetic waves incident on the radome.

Radome is a compound word of radar and dome. It is a structure to protect the radar antenna from the external environment such as heat, moisture and mechanical shock. The application of the stealth technique to the radome should reflect the electromagnetic wave transmitted from the counterpart radar in the traveling direction to minimize the electromagnetic wave back to the counterpart radar and transmit the electromagnetic wave transmitted and received by the antenna inside the radome. In terms of RCS, radar antennas are the main sources of reflection of electromagnetic waves, and the proportion of the entire RCS in weapon systems is very high.

Therefore, to reduce the RCS of the weapon system, it is necessary to apply the stealth technology to the radar.

In order to realize this, a frequency selective surface membrane (FSS) capable of transmitting electromagnetic waves corresponding to a frequency of a specific band incident to the radome and reflecting electromagnetic waves of other frequency bands and a composite capable of withstanding the external environment Materials are used for the radome structure.

Since the frequency selective permeable membrane acts as a factor influencing the selective transmission characteristics of the electromagnetic waves of the radome, researches on the structure and pattern of the frequency selective permeable membrane and related manufacturing methods for improving the broadband electromagnetic transmission characteristics have been actively conducted in recent years. have.

In addition, the fiber reinforced composites, foam or honeycomb with excellent specific strength and specific rigidity in the design of the radome considering durability, mechanical strength, stiffness, and aerodynamic effects on the external environment. Sandwich composites with Honeycomb are being applied to radome structures.

 Aircraft and ships equipped with radome are inevitably exposed to high and low temperature environmental conditions.A temperature gradient is generated by the temperature difference between the composite material of the inner layer and the composite material of the inner layer which is directly exposed to the external environment. Thermal stress is generated throughout.

This results in deformation and damage of the frequency selective permeable membrane, and also interfacial failure may occur in the external weak impact between the composite material and the foam.

Therefore, the design and fabrication of a radome structure that satisfies the excellent shock characteristics, vibration absorption and low shrinkage characteristics under various dynamic load conditions and high and low temperature environmental conditions can be considered.

One embodiment of the present invention is to provide a radome having better performance even when directly exposed to the external environment.

In order to achieve the above object of the present invention, the low-detection radome according to an embodiment of the present invention, a plurality of bodies formed to cover the antenna device, the support on which the antenna device is disposed and the support is extended And a support shaft formed to support the any one body, wherein the body includes one side and the other side of the frequency selective transmission layer and the frequency selective transmission layer which are formed to transmit a frequency transmitted and received through the antenna unit. A first cover layer is formed to include a first foam layer and a second foam layer respectively coupled to the outer periphery of the body.

According to an example related to the present invention, the first cover layer may be arranged such that a plurality of prepregs including aramid fibers cover each side of the body, and may be bonded to each other.

According to an example related to the present invention, the bodies may be integrally formed by combining side surfaces of adjacent bodies so as to be adjacent to each other.

According to an example related to the present invention, a second cover layer may be formed between the body and the first cover layer to protect the body.

According to an example related to the present disclosure, the second cover layer may include a plurality of prepregs including glass fibers to cover respective sides of the body, and may be combined with each other to be integrally formed with the body. Can be.

According to an example related to the present invention, the first cover layer is disposed such that a plurality of prepregs including glass fibers cover respective surfaces of the first and second foam layers to which the first cover layer is bonded, respectively, An edge portion including aramid fibers is formed along the outer circumference of the pregs, and the edge portions disposed adjacent to each other may be coupled to each other.

According to an example related to the present invention, the base of the material forming the first foam layer and the second foam layer may include at least one of PMI, PS, PVC, polyurethane, epoxy, or phenol.

According to an example related to the present invention, the aramid fibers, may be formed including at least one of short fibers, long fibers or pulp fibers.

In order to realize the above object, the present invention includes a moving body moving at a low speed or a high speed, an antenna device mounted on the moving body and a radome structure formed to cover the antenna device, wherein the radome structure is a plurality of A body, a support on which the antenna device is disposed, and a support shaft extending from the support, the support shaft being formed to support the one body, wherein the body transmits a frequency transmitted and received through the antenna unit. A low skin comprising a frequency selective transmission layer formed and a first foam layer and a second foam layer respectively coupled to one surface and the other surface of the frequency selective transmission layer, the first cover layer is formed to surround the outer periphery of the body Disclosed is an athletic body having a detection radome.

The low-detection radome according to at least one embodiment of the present invention configured as described above can maintain the overall stiffness of the radome even when exposed to various dynamic loads and high and low temperature environmental conditions.

In addition, the radome according to an embodiment of the present invention has a low heat transfer coefficient, thereby enabling stable operation of the antenna devices.

Since each body constituting the radome is formed to have an integral box shape, the productivity and stability can be increased, and the compressive strength can be increased to have resistance to compression and impact loads.

1 is a perspective view of a radome associated with one embodiment of the present invention.
FIG. 2 is a cross sectional view taken along the line IV-IV of FIG. 1;
3 is a conceptual view of a part related to the body of the cross-sectional view shown in FIG.
4 is a conceptual diagram illustrating modified embodiments of FIG. 3.
5A through 5C are conceptual views illustrating modified embodiments of FIG. 2.
6A to 6B are graphs comparing dielectric constants of glass fibers and aramid fibers, respectively.
7 and 8 is a conceptual diagram in a state where the radome is attached to a ship or aircraft according to an embodiment of the present invention.

Hereinafter, a low-detection radome and an athletic body having the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role.

In the present specification, the same or similar reference numerals are given to different embodiments in the same or similar configurations. As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

One embodiment of the present invention relates to a radome mounted on a ship or aircraft. The actual ship radome is made of a large structure with a height of 20m or more, and the structural rigidity increase and weight loss of the structure act as important variables in the design and manufacture of the ship radome.

Accordingly, embodiments of the present invention are directed to the design and fabrication of a radome of a lightweight, high-strength hybrid structure consisting of a cover layer and a foam layer formed by reinforcing arimid fibers.

As such, embodiments of the present invention increase the structural stiffness of low-detection radome structures exposed to various dynamic loads and high and low temperature environmental conditions, and due to self-heat shrinkage of the cover layer and PVC foam layer formed from existing glass fiber composite materials. In order to reduce the thermal stress caused, it is characterized in that the reinforcement of the aramid fibers having excellent specific stiffness and specific strength and low coefficient of thermal expansion when producing the cover layer and the core foam layer formed of the composite material.

The coefficient of thermal expansion of glass fibers is about 7.0 × 10 −6 m / m · ° C., whereas the aramid fibers have a negative coefficient of thermal expansion of about −2.2 × 10 −6 m / m · ° C.

Through this, if the coefficient of thermal expansion of the core foam layer itself is reduced, there is an effect of reducing the stress acting at the interface with the cover layer formed of the aramid reinforced composite material of the outer layer.

In addition, the antenna and the surrounding equipment installed inside the radome for external communication are sensitive to temperature changes in the external environment. The low heat transfer coefficient (about 1.8 W / m · K) of the aramid fiber ensures stable operation of the antenna equipment. Make it possible.

In addition, in order to improve the structural rigidity in the thickness direction, the core foam layer filled with a polymer foam layer, aerosol, etc., inside the box-shaped structure made of a cover layer formed of an aramid composite material, it is possible to increase productivity and safety at the same time. have.

Through this, the compressive strength is increased to increase the strength against compression and impact loads.

In the case of manufacturing a radome, after manufacturing a radome panel consisting of a cover layer and a foam layer formed of a large area of a composite material, a plurality of panels are installed and bonded for the manufacture of a square or octagonal radome structure.

At this time, there is a connection part connecting the panel part, and there is a possibility of fatigue failure due to fatigue life deterioration at the joint part of the radome panel which is not finished due to the effect of repeated dynamic load during operation.

One embodiment of the present invention is to increase the structural rigidity in the thickness direction through the integrated box-shaped radome panel design, and to improve the productivity of the cover layer formed of a box-type composite material core with aramid composite prepreg (Prepreg) It is characterized by enclosing the outside of the foam layer and curing at the same time to form the outer layer of the radome.

In addition, the radome in the form of an integrated box can partially repair the radome panel damaged and damaged by an impact on the outside, and can be easily replaced to improve workability.

Hereinafter, the structure of the low-detection radome associated with an embodiment of the present invention will be described with reference to this drawing.

1 is a perspective view of a radome according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line IV-IV of FIG. 1, and FIG. 3 is a conceptual diagram of a part related to the body of the cross-sectional view shown in FIG.

The low-detection radome 100 may include a plurality of bodies 110, a support 140, and a support shaft 150.

As shown in FIG. 2, the antenna device 160 is disposed on the support 140. The bodies 110 are coupled to each other to define a space including the antenna device 160. The shape of the radome coupled to the body 110 may be a square pillar or an octagonal pillar or other polyhedron.

The support shaft 150 may further include a support shaft 150 extending from the support 140 to any one body 110 to support the body 110.

As shown in FIG. 3, the body 110 has a first foam layer 112 and a second foam layer 113 formed on both surfaces thereof with a frequency selective transmission layer 111 interposed therebetween. The first foam layer 112 and the second foam layer 113 is at least one of synthetic resins such as polymethacrylimide (PMI), polyurethane (Polyurethane), phenol (Phenol), PS (Polystylen), PVC (Polyvinyl chloride), epoxy, etc. It is formed by adding at least one of aramid short fibers, long fibers or pulp fibers as a reinforcing material.

The first foam layer 112 and the second foam layer 113 formed in this way can improve the compressive strength of each foam layer and reduce the thermal deformation of the material itself.

In addition, it is possible to prevent deformation and breakage of the frequency selective permeable membrane which may occur in an external shock and moisture environment, and at the adhesive interface between the first and second foam layers 112 and 113 and the frequency selective permeable layer 111. Cracks can be prevented.

Referring to FIG. 3, the first cover layer 120 is formed to cover the body 110. The first cover layer 120 may be formed in a 'c' shape or a '-' shape so as to cover the plate-shaped body 110 to be coupled to each other to surround the body 110.

Thus, the panel 101 may be formed including the body 110 and the first cover layer 120. As described above, the panels 101 may be formed of a polyhedron having an overall shape coupled to each other to define a space in which the antenna is disposed.

The method of forming the first cover layer 120 may be performed by laminating prepregs including aramid fibers on the body 110 and simultaneously curing adhesively.

That is, a plurality of prepregs including aramid fibers are disposed to cover each side of the body 110, respectively, and are bonded to each other.

The panels 101 may be fixed to each other by fastening means such as adhesive or screws. As a result, the bodies 110 may be integrally formed by coupling the side surfaces of the bodies 110 adjacent to each other to be adjacent to each other.

As a result, the combination of the first cover layer 120 and the first foam layer 112 or the second foam layer 113 having a coefficient of thermal deformation close to zero minimizes deformation even at high and low temperature environmental conditions, and a frequency selective transmission layer. It is possible to reduce the stress applied at the interface between the (111) and the first foam layer 112 or the second foam layer 113.

In general, in the radome, the amount of stress and strain applied to the bonding interface of the materials may vary according to the material of each cover layer and the first foam layer 112 or the second foam layer 113, and the external repetitive dynamic load and impact load This results in the generation of cracks in the adhesive at the bonding interface and the delamination and deformation of the frequency selective permeable membrane layer, which can result in the loss of electromagnetic wave transmission properties of the radome.

However, as described above, by using the cover layer reinforced with aramid fibers in the first foam layer 112 or the second foam layer 113 containing aramid, it is possible to form a radome of various shapes, the shock and vibration characteristics Can make excellent radome.

That is, the low detection radome 100 using the aramid fibers according to an embodiment of the present invention by minimizing the possibility of damage and deformation of the frequency selective transmission layer 111 that may be generated by an external impact, various dynamic loads or Even under high and low temperature environmental conditions, the excellent transmittance of electromagnetic waves of the radome can be ensured.

As shown in FIG. 3, a second cover layer 130 may be formed between the body 110 and the first cover layer 120 to protect the body 110.

Since a plurality of cover layers is formed, the compressive strength can be increased to increase the resistance to compressive and impact loads.

Here, the second cover layer 130 is disposed so that a plurality of prepregs including glass fibers cover respective surfaces of the body 110, and are combined with each other to be integrally formed with the body 110. Can be.

4 is a conceptual diagram illustrating a modified embodiment of FIG. 3.

As shown in FIG. 4, the first cover layer 120 ′ includes the first and second foam layers in which glass fiber portions 121 including a plurality of prepregs including glass fibers are combined. Arranged to cover each side of the (112, 113), respectively, along the outer periphery of the prepreg is formed a border portion 122 including aramid fibers, adjacent edges disposed adjacent to each other can be formed to be bonded to each other have.

As such, by using the aramid fibers only in contact with the body 110 or the panel 101 other than the whole, manufacturing cost can be reduced and easy molding can be achieved.

5A through 5C are conceptual views illustrating modified embodiments of FIG. 2.

As shown in FIG. 5A, the first cover layer and the second cover layer may be integrally formed with 120 ″.

In addition, as shown in Figures 5b to 5c, the low-detection radome may be formed to have a polygonal cross section.

6A to 6B are graphs comparing frequency transmittances of glass fibers and aramid fibers, respectively. FIG. 6A is a dielectric constant of a cover layer including glass fibers, and FIG. 6B is a dielectric constant of a cover layer including aramid fibers. .

As shown, it can be seen that the cover layer comprising aramid fibers is lower than the dielectric constant of the cover layer comprising glass fibers.

7 and 8 are conceptual diagrams in a state where the radome is attached to the ship or aircraft according to an embodiment of the present invention, Figure 7 is a view of the radome is attached to the vessel, Figure 8 is a radome is attached to the aircraft It is a drawing of the state.

Low speed or high speed moving bodies such as ships 200 and 300 are required for radar to distinguish the pia, and as a structure for protecting the radar antenna from the external environment such as heat, moisture, and mechanical shock. The radome 100 described above may be mounted at any one point of the moving object.

In addition, since the stealth technique for the radome is required, the electromagnetic wave transmitted from the counterpart radar is reflected in the advancing direction to minimize the electromagnetic waves returned to the counterpart radar, and to transmit and transmit the electromagnetic waves transmitted and received by the antenna inside the radome. The same radome is required.

The low-detection radome described above and the athletic body having the same may not be limitedly applied to the configuration and method of the above-described embodiments, but the embodiments may be all or part of each of the embodiments so that various modifications may be made. It may alternatively be configured in combination.

Claims (9)

A plurality of bodies formed to cover the antenna device;
A support on which the antenna device is disposed; And
A support shaft extending from the support and configured to support the one body,
The body,
A frequency selective transmission layer formed to transmit a frequency transmitted and received through the antenna unit; And
A first foam layer and a second foam layer respectively bonded to one surface and the other surface of the frequency selective transmission layer,
A low-detection radome, characterized in that the first cover layer is formed to surround the outer periphery of the body. The method of claim 1,
The first cover layer,
A low-detection radome characterized in that a plurality of prepregs including aramid fibers are disposed to cover each side of the body, respectively, and are bonded to each other. The method of claim 2,
The bodies,
Low-detection radome, characterized in that the side of each adjacent body is formed integrally coupled to be adjacent to each other. The method of claim 2,
And a second cover layer is formed between the body and the first cover layer to protect the body. 5. The method of claim 4,
The second cover layer,
A plurality of prepregs including glass fibers are disposed to cover each side of the body, respectively, coupled to each other low detectability radome characterized in that formed integrally with the body. The method of claim 1,
The first cover layer,
A plurality of prepregs comprising glass fibers are arranged to cover each side of the first and second foam layers, respectively, joined together,
An edge portion including aramid fibers is formed along the outer circumference of the prepregs,
Low-detection radome, characterized in that the adjacent edge portion is disposed adjacent to each other. The method according to claim 6,
The base of the material forming the first foam layer and the second foam layer,
A low-detection radome comprising at least one of PMI, PS, PVC, polyurethane, epoxy or phenol. The method of claim 7, wherein
The aramid fiber,
Low-detection radome, characterized in that corresponding to at least one of short fibers, long fibers or pulp fibers. A moving body moving at a low or high speed;
An antenna device mounted to the moving body; And
It includes a radome structure formed to cover the antenna device,
The radome structure,
A plurality of bodies;
A support on which the antenna device is disposed; And
A support shaft extending from the support and configured to support the one body,
The body,
A frequency selective transmission layer formed to transmit a frequency transmitted and received through the antenna unit; And
A first foam layer and a second foam layer respectively bonded to one surface and the other surface of the frequency selective transmission layer,
The body having a low-detection radome, characterized in that the first cover layer is formed to surround the outer periphery of the body.

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