KR102607515B1 - Radiating element array structure and active electronically scanned array radar system with the same - Google Patents

Abstract

A radiating element array structure and an AESA radar system including the same may be disclosed. A radiation element array structure according to an embodiment includes a first radiation unit; a single radiating element comprising a second radiating portion; And a radiating element array arranged in a plurality of preset numbers according to the radiating element array specification for forming a single radiating element composed of first and second radiating elements, and the first and second radiating elements of the single radiating element. A dielectric cap with a preset thickness and dielectric constant can be applied to the end, and a WAIM structure with a preset thickness and dielectric constant can be applied to the front of the single radiation element.

Description

Radiating element array structure and AESA radar system including the same {RADIATING ELEMENT ARRAY STRUCTURE AND ACTIVE ELECTRONICALLY SCANNED ARRAY RADAR SYSTEM WITH THE SAME}

The present invention relates to a radiating element array structure capable of minimizing the active reflection coefficient and an AESA radar system including the same.

The content described in this section simply provides background information for this embodiment and does not constitute prior art.

AESA (Active Electronically Scanned Array) radar system consists of an array antenna composed of a plurality of transmitting and receiving elements, and can form a beam in a desired direction by electronically changing the phase of the array that makes up the antenna. It has the advantage of high accuracy as well as detection distance.

In addition, the electronic beam steering of the AESA radar system can variably control the size and phase of the signal through a transmitting/receiving module (TRM) for each array element.

Meanwhile, when the AESA radar system operates in transmission mode, signals with different phases are emitted from each of the multiple array elements, and in this case, in addition to the reflected signal of the signal radiated from a specific channel, it is combined with the incoming signal from adjacent elements. Due to its influence, it has poor active reflection coefficient characteristics.

An increase in the active reflection coefficient may result in a reflected signal exceeding a threshold being applied to the TRM of a specific channel, causing the TRM to fail. Additionally, AESA radar performance may deteriorate or become unoperable.

Therefore, in order to reduce these reflected signals, there is a need to optimize the radiator (radiating element) itself used in the array structure, and there is a need to optimize the active reflection coefficient through the use of additional structures or additional optimization of the radiating element.

The present invention can provide a radiating element array structure that can minimize the active reflection coefficient and promote stable operation of the system by applying WAIM to the front of a single radiating element included in the radiating element array, and an AESA radar system including the same. there is.

According to an embodiment of the present invention, a radiation element array structure can be disclosed.

A radiation element array structure according to an embodiment includes a first radiation unit; a single radiating element comprising a second radiating portion; And a radiating element array arranged in a plurality of preset numbers according to the radiating element array specification for forming a single radiating element composed of first and second radiating elements, and the first and second radiating elements of the single radiating element. A dielectric cap with a preset thickness and dielectric constant can be applied to the end, and a WAIM structure with a preset thickness and dielectric constant can be applied to the front of the single radiation element.

According to one embodiment, a plurality of single radiation elements included in the radiation element array may be linearly arranged in the horizontal direction.

According to one embodiment, a plurality of single radiation elements included in the radiation element array may be linearly arranged in the vertical direction.

According to one embodiment, the dielectric cap may be applied to the ends of the first radiating portion and the second radiating portion in a cap shape at a preset depth.

According to one embodiment, the dielectric cap is shaped like a chair ( ) can have.

According to one embodiment, a notch may be formed on at least one side of the dielectric cap toward the inside of the dielectric cap.

According to one embodiment, the dielectric cap can be formed to have a dielectric constant of 2.2 and a thickness of 1.0 mm.

According to one embodiment, the WAIM structure may have a dielectric constant of 2.2, a thickness of 2.0 mm, and a distance of 3.0 mm from a single radiating element.

According to one embodiment, the single radiating element may form a stepped slot between the first radiating part and the second radiating part.

According to one embodiment, the stepped slot may be configured in the form of a stepped notch rising upward.

According to one embodiment, the stepped slot includes an upper slot formed on the upper side of the first radiating portion and the second radiating portion; It includes a lower slot formed on the lower side of the first radiating part and the second radiating part. The upper slot may have a width of 10.3 mm, and the lower slot may have a width of 3.4 mm.

According to one embodiment, the first radiating portion and the second radiating portion may be configured to be symmetrically shifted in the horizontal direction.

According to one embodiment, the first radiating part is composed of an upper part where radiation occurs, a lower part extending below the upper part, and a first support part extending below the lower part to support the upper and lower parts, and the upper part, the lower part, and the first support part are integrated. can be formed.

According to one embodiment, the second radiating part is composed of an upper part where radiation occurs, a lower part extending below the upper part, and a second support part extending below the lower part to support the upper and lower parts, and the upper part, the lower part, and the second support part are integrated. can be formed.

According to one embodiment, a power feeder for feeding power may be included between the first support part of the first radiating part and the second support part of the second radiating part.

According to one embodiment, an absorber having an absorption rate according to the radiation element specifications and a metal ground performing a grounding function may be sequentially formed at the bottom of the first radiating part and the second radiating part.

According to one embodiment, a coaxial port is built into the bottom of the metal ground to form a third support unit to electrically and structurally support the single radiation element.

According to one embodiment, the radiation element array structure may be configured as a 13*13 sub-array structure.

According to one embodiment, the radiating element array structure may operate in the X-band band (8.5 - 9.6 GHz).

According to one embodiment, the single radiating element has a vertical length including the upper and lower portions of the first radiating portion of 22 mm, a horizontal length including the first radiating portion and the second radiating portion of 18.7 mm, and is disposed at the uppermost end of the first radiating portion. The total vertical length of the single radiation element including the bottom of the third support part can be 58.0 mm.

According to an embodiment of the present invention, an AESA radar system having a radiating element array structure can be disclosed.

An AESA radar system according to an embodiment includes a radiating element array having a radiating element array structure according to any one of claims 1 to 20; A plurality of transmitting and receiving modules each corresponding to a plurality of single radiation elements included in the radiation element array; In order to minimize the active reflection coefficient that increases in a specific channel when transmitting a signal through a plurality of transmitting and receiving modules, the thickness and dielectric constant parameters of the dielectric cap applied to the ends of the first and second radiating portions of the single radiation element are optimized. Optimizing the parameters of the thickness, dielectric constant, and distance from the radiation element for the WAIM structure applied to the front surface of the first and second radiation elements of the single radiation element, and adjusting the size and phase of the coupling coefficient with adjacent radiation elements. May include a control module.

According to various embodiments of the present invention, the active reflection coefficient can be minimized by applying WAIM to the front surface of a single radiation element included in a radiation element array and optimizing the dielectric constant, thickness, and distance from the radiation element of the WAIM structure.

In addition, by adjusting the size and phase of the coupling coefficient with adjacent array elements for a single radiation element to which WAIM is applied, the active reflection coefficient that increases in a specific channel can be optimized.

In addition, the present invention applies an optimized radiating element array structure in an AESA radar system for aircraft or seekers with a large beam steering angle, thereby achieving the effect of increasing stable operation, performance, and lifespan of the system.

1 is a structural diagram of a radiation element array of an AESA radar system according to an embodiment of the present invention.
Figure 2 is a cross-sectional view of a single radiation element applied to an AESA radar system according to an embodiment of the present invention.
Figure 3 is a structural diagram of a single radiation device according to an embodiment of the present invention.
Figure 4 is a detailed structural diagram of a single radiation device according to an embodiment of the present invention.
Figure 5 is an example diagram showing the parameters shown in Figure 4.
Figure 6 is an example of a dielectric cap applied to a single radiation device according to an embodiment of the present invention.
Figure 7 is an exemplary diagram of a radiation element array in which single radiation elements are arranged 13*13 in the horizontal and vertical directions according to an embodiment of the present invention.
Figure 8 is a structural diagram of a single radiation element according to an embodiment of the present invention.
Figure 9 is another exemplary diagram of a single radiation device according to an embodiment of the present invention.
Figure 10 is a structural diagram of WAIM applied to the front surface of a single radiation element according to an embodiment of the present invention.
Figure 11 is a left cross-sectional view of a single radiation device applying WAIM according to an embodiment of the present invention.
Figure 12 is a schematic diagram of an AESA radar system applying a radiation element array according to an embodiment of the present invention.
Figure 13 is a conceptual diagram of the active reflection coefficient.
Figure 14 is an antenna structure diagram according to simulation of the present invention.
Figure 15 is an exemplary comparison of the active reflection coefficient performance of a radiation element array structure according to an embodiment of the present invention.
Figure 16 is an example of an active reflection pattern in a radiation element array structure according to an embodiment of the present invention.
Figure 17 is an example of an active reflection pattern of a conventional AESA radar system.

Embodiments of the present invention are illustrated for the purpose of explaining the technical idea of the present invention. The scope of rights according to the present invention is not limited to the embodiments presented below or the specific description of these embodiments.

All technical and scientific terms used in the present invention, unless otherwise defined, have meanings commonly understood by those skilled in the art to which the present invention pertains. All terms used in the present invention are selected for the purpose of more clearly explaining the present invention and are not selected to limit the scope of rights according to the present invention.

Expressions such as "comprising", "comprising", "having", etc. used in the present invention are open terms that imply the possibility of including other embodiments, unless otherwise stated in the phrase or sentence containing the expression. It should be understood as (open-ended terms).

Singular expressions described in the present invention may include plural meanings unless otherwise specified, and this also applies to singular expressions recited in the claims.

Expressions such as “first” and “second” used in the present invention are used to distinguish a plurality of components from each other and do not limit the order or importance of the components.

The term “unit” used in the present invention refers to software or hardware components such as a field-programmable gate array (FPGA) or an application specific integrated circuit (ASIC). However, “wealth” is not limited to hardware and software. The “copy” may be configured to reside on an addressable storage medium and may be configured to reproduce on one or more processors. Thus, as an example, “part” refers to software components, such as object-oriented software components, class components, and task components, processes, functions, properties, procedures, subroutines, Includes segments of program code, drivers, firmware, microcode, circuits, data, databases, data structures, tables, arrays, and variables. The functionality provided within components and “parts” may be combined into smaller numbers of components and “parts” or may be separated into additional components and “parts”.

As used in the present invention, the expression "based on or on the basis of" is used to describe one or more factors that influence the act or operation of a decision judgment, which are described in the phrase or sentence containing the expression, , this expression does not exclude additional factors that influence the decision, act or action of judgment.

In the present invention, when a component is referred to as being “connected” or “connected” to another component, it means that the component can be directly connected or connected to another component, or in a new different configuration. It should be understood as something that can be connected or connected through elements.

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. In the accompanying drawings, identical or corresponding components are given the same reference numerals. Additionally, in the description of the following embodiments, overlapping descriptions of identical or corresponding components may be omitted. However, even if descriptions of components are omitted, it is not intended that such components are not included in any embodiment.

Figure 1 is an exemplary diagram of the radiating element array structure of an AESA radar system according to an embodiment of the present invention.

Referring to FIG. 1, the radiating element array structure includes a single radiating element 100 including a first radiating unit 101 and a second radiating unit 103, and a radiating element configured by arranging a plurality of single radiating elements as many as a preset number. It may include an array 10. A preset distance 110 may be maintained between single radiation elements included in the radiation element array 10 for electrical separation and interference avoidance.

In a radiation element array structure, a radiation pattern (or radiation pattern) is formed according to the principle of pattern product of the radiation pattern of a single radiation element and an array factor. The radiation pattern characteristics of a single radiating element affect the radiation pattern characteristics of the entire radiating element array. Therefore, the radiating element array structure according to an embodiment of the present invention can minimize the active reflection coefficient by optimizing the design of a single radiating element.

In one embodiment, the single radiation element 100 is configured with a step flare notch arrangement. The single radiation element 100, indicated by a black circle, has a structure that forms stepped slots 135 and 137 between the first radiating part 101 and the second radiating part 103.

The stepped slots 135 and 137 are formed to adjust impedance matching in a specific channel and bandwidth. In one embodiment, the stepped slots 135 and 137 may be formed in a rising shape that becomes wider upward. The antenna bandwidth can be expanded by forming the stepped slots 135 and 137 in a shape that gradually widens toward one side.

The stepped slot can be configured in the form of a stepped notch rising upward. In other words, it has a stepped shape rising upward from a flat segment, and the width of the formed slot becomes wider as it goes upward. For example, the stepped slots 135 and 137 are formed between the first radiating part 101 and the second radiating part 103, and are formed on the bent surfaces of the first radiating part 101 and the second radiating part 103. Formed by, overall It can be made into a shape.

In one embodiment, the first radiating portion 101 and the second radiating portion 103 may be configured to be symmetrically shifted in the horizontal direction. For example, the first radiation portion 101 is It is composed of a shape, and the second radiating portion 103 is It can be made into a shape.

Although not shown, the single radiating element 100 is supported by a plurality of electrical and structural support components, and feed lines that supply current to the first and second radiating units are electrically coupled.

In addition, the radiation element array 10 structure in which a plurality of single radiation elements 100 are arranged can be applied to an AESA radar system for aircraft or seekers that requires wide-angle beam steering. At this time, depending on the antenna performance to be configured or the specifications of the radiation element array to be implemented, a plurality of radiation elements are configured as preset. Additionally, a transmission/reception module that transmits and receives signals through each radiation element 100 may be mounted on the back of each single radiation element 100.

When a signal is applied to the first and second radiating units (101, 103) through the feed line, the antenna device with the radiation element array structure configured as described above transmits the signal to the target through both ends of the first and second radiating units (101, 103). , and the presence of the target is detected using the signal reflected from the target.

In the present invention, slots 110 having a constant spacing in the longitudinal direction may be formed between the plurality of single radiation elements 100 arranged in the radiation element array structure 10. Slot 110 can help optimize the active reflection coefficient of the antenna element (or radiation element). In other words, the gap area allows the single radiation elements to be spaced and separated, and is filled with a non-conductive or low-conductivity material such as air.

In one embodiment, the predetermined interval 110 may be configured to isolate the first radiating part 101 of the single radiation element 100 from the radiating part of other single radiation elements. Additionally, the predetermined interval 110 may be configured to isolate the second radiating portion 103 of the single radiation element 100 from the radiating portion of other single radiation elements.

In this way, a certain gap 110 may be formed between single radiation elements to electrically isolate them from other single radiation elements. That is, a gap 110 for isolation between single radiation elements may be formed between the first radiating part 101 and the radiating part of another single radiation element. Additionally, a gap 110 may be formed between the second radiating part 103 and the radiating part of another single radiation element.

At this time, the active reflection coefficient of the single radiation element 100 can be optimized by optimizing the constant spacing 110. Therefore, by optimizing the width parameter of the gap 110 and adjusting the size and phase of the coupling coefficient between adjacent radiation elements through this, it is possible to minimize the active reflection coefficient by canceling out the signals reflected from a specific channel. For example, the constant interval 110 may have a width of 0.8 mm and a length of 36.5 mm.

The ends of the single radiation device 100 of the present invention are equipped with dielectric caps 120 and 130. Referring to FIG. 1, a first dielectric cap 120 is applied to the end of the first radiating part 101, and a second dielectric cap 130 is applied to the end of the second radiating part 103. there is.

The dielectric caps 120 and 130 can minimize the active reflection coefficient of the single radiation element 100 by optimizing the thickness and dielectric constant. That is, by optimizing the thickness and dielectric constant of the dielectric caps 120 and 130 and adjusting the size and phase of the coupling coefficient with nearby array elements, the active reflection coefficient that increases in a specific channel can be minimized.

In one embodiment, the dielectric caps 120 and 130 have a dielectric constant of 2.2 and can be formed to a thickness of 1 mm.

Therefore, when a signal is applied to the first and second radiating units 101 and 103 through the feed line, the signal traveling along the first and second radiating units 101 and 103 is radiated to the target. Thereafter, the signal intensity remaining in the radiating portions 101 and 103 is gradually weakened by the optimized dielectric constant of the dielectric caps 120 and 130, the size and phase of the coupling coefficient with nearby array elements, etc., and no additional radiation occurs. In this way, the dielectric caps 120 and 130 minimize the active radiation coefficient that increases in a specific channel through optimized parameters and coupling characteristics with nearby array elements.

Referring to FIG. 1, the active reflection coefficient of the radiation element 100 is determined by the optimized design characteristics of the single radiation element 100 and the first and second radiating units 101 and 103 of the radiation element 100. Based on the optimized parameters of the applied dielectric caps 120 and 130, the size and phase of the coupling coefficient with nearby radiation elements can be adjusted to minimize the active reflection coefficient that increases in a specific channel.

The radiation element array structure of the present invention shown in FIG. 1 consists of a plurality of radiation elements arranged in a step flare notch arrangement. In the illustrated embodiment, a portion (radiating area) of other radiation elements is shown centered on a single radiation element 100, but the number of radiation elements designed according to the implementation design of the radiation element array may increase by a set amount. The radiation element array structure of the present invention can be manufactured using general antenna manufacturing methods. For example, using the 3D printing manufacturing method, it can be manufactured quickly, accurately, and at low cost. Alternatively, the radiating element array may be manufactured by etching onto a dielectric substrate, or by machining from a metal plate.

Figure 2 is a cross-sectional view of a single radiation device according to an embodiment of the present invention.

The radiation element 100 includes a first radiating portion 101 and a second radiating portion 103, and stepped slots 137 and 135 are formed between the first radiating portion 101 and the second radiating portion 103. It can be.

The stepped slots 137 and 135 may be formed in an upward shape that becomes wider upward. For example, stepped slots 137 and 135 may be formed between the first radiating part 101 and the second radiating part 103.

In one embodiment, the stepped slots 137 and 135 are formed between the first radiating portion 101 and the second radiating portion 103, and the first radiating portion 101 and the second radiating portion 103 are bent. It is formed between the faces (105, 107, 109, 111), and overall It can be made into a shape.

The first radiating part 101 includes an upper part 115 where radiation occurs and a lower part 117 extending below the upper part, and the second radiating part 103 includes an upper part 121 where radiation occurs and a lower part 117 extending below the upper part. It is configured to include an extending lower portion 123.

In one embodiment, the first radiating portion 101 and the second radiating portion 103 may be formed to be left-right symmetrical in the horizontal direction.

In one embodiment, the lower part 117 of the first radiating part 101 may have a wider radiating part than the upper part 115. Conversely, the upper part 115 of the first radiating part 101 may have a narrower radiating part than the lower part 117.

In one embodiment, the lower part 123 of the second radiating part 103 may have a wider radiating part than the upper part 121. Conversely, the upper part 121 of the second radiating part 103 may have a narrower radiating part than the lower part 123.

In one embodiment, the bent surface 109 in contact with the lower part 117 of the first radiating part 101 protrudes more than the bent surface 105 of the upper part 115 in the direction of the second radiating part 103. 2 The slot 130 formed between the radiating portion 103 and the upper slot 135 may be narrower than the upper slot 135.

In one embodiment, the surface 105 in contact with the upper part 115 of the first radiating part 101 protrudes less than the bent surface 109 of the lower part 117 in the direction of the second radiating part 103, thereby forming a second radiating part 101. The slot 135 formed between the radiating portion 103 and the lower slot 130 may be wider than the lower slot 130.

Likewise, the bent surface 111 in contact with the lower part 123 of the second radiating part 103 may protrude further than the bent surface 107 of the upper part 121 in the direction of the first radiating part 101. The bent surface 107 in contact with the upper part 121 of the second radiating part 103 may protrude less than the bent surface 111 of the lower part 123 in the direction of the first radiating part 101.

A first dielectric cap 120 is applied to the end of the first radiation portion 101 of the radiation element 100. The first dielectric cap 120 is applied to the end of the first radiating portion 101 similar to the shape of a hat.

A second dielectric cap 130 is applied to the end of the second radiating portion 103 of the radiation element 100. The second dielectric cap 130 is applied to the end of the second radiating portion 103 similar to the shape of a hat.

The first and second dielectric caps 120 and 130 can minimize the active reflection coefficient of the single radiation element 100 by optimizing the thickness and dielectric constant. That is, by optimizing the thickness and dielectric constant of the dielectric caps 120 and 130 and adjusting the size and phase of the coupling coefficient with nearby array elements, the active reflection coefficient that increases in a specific channel can be minimized.

In one embodiment, the dielectric caps 120 and 130 have a dielectric constant of 2.2 and can be formed to a thickness of 1 mm.

Referring to FIG. 2, the configuration of the first radiating unit 101 and the second radiating unit 103 included in the single radiation element is shown in cross section. However, in the drawings described later, a single radiation element may include a support portion and several components for electrical/structural support in addition to the first radiating portion and the second radiating portion. In this case, parts other than the first and second radiating parts can be formed in various shapes.

Figure 3 shows a detailed view of a single radiation device according to one embodiment of the present invention.

The radiation element of the present invention is configured with a step flare notch arrangement. The illustrated radiation element 200 can be manufactured using a general antenna manufacturing method. For example, the radiating element can be manufactured by etching on a dielectric substrate, or by processing from a metal plate. Additionally, using the 3D printing manufacturing method, it can be manufactured quickly, accurately, and at low cost.

The radiation element 200 includes a first radiating portion 201 and a second radiating portion 203, and stepped slots 237 and 235 are formed between the first radiating portion 201 and the second radiating portion 203. It can be. The stepped slots 237 and 235 may be formed in an upward shape that becomes wider upward.

In one embodiment, the stepped slots 237 and 235 are formed between the first radiating portion 201 and the second radiating portion 203, and the first radiating portion 201 and the second radiating portion 203 are bent. It is formed between the faces (205, 207, 209, 211), and overall It can be made into a shape.

The first radiating part 201 includes an upper part 215 where radiation occurs, a lower part 217 extending below the upper part, and a first support part 219 extending below the lower part and supporting the upper and lower parts. The second radiating part 203 includes an upper part 221 where radiation occurs, a lower part 223 extending below the upper part, and a second support part 225 extending below the lower part and supporting the upper and lower parts. In one embodiment, the first radiating part 201 may integrally form an upper part, a lower part, and a first support part. Likewise, the second radiating part 203 may form an upper part, a lower part, and a second support part integrally.

In one embodiment, the first radiating portion 201 and the second radiating portion 203 may be formed to be left-right symmetrical in the horizontal direction.

In one embodiment, the lower part 217 of the first radiating part 201 may have a wider radiating part than the upper part 215. Conversely, the upper part 215 of the first radiating part 201 may have a narrower radiating part than the lower part 217.

In one embodiment, the lower part 223 of the second radiating part 203 may have a wider radiating part than the upper part 221. Conversely, the upper part 221 of the second radiating part 203 may have a narrower radiating part than the lower part 223.

In one embodiment, the bent surface 209 in contact with the lower part 217 of the first radiating part 201 protrudes further than the bent surface 205 of the upper part 215 in the direction of the second radiating part 203. 2 The slot 237 formed between the radiating portion 203 may be narrower than the upper portion.

In one embodiment, the surface 205 in contact with the upper part 215 of the first radiating part 201 protrudes less than the curved surface 209 of the lower part 217 in the direction of the second radiating part 203, thereby forming a second radiating part 201. The slot 235 formed between the radiating portion 203 may be wider than the lower portion.

Similarly, the bent surface 211 in contact with the lower part 223 of the second radiating part 203 may protrude further than the bent surface 207 of the upper part 221 in the direction of the first radiating part 201. The bent surface 207 in contact with the upper part 221 of the second radiating part 203 may protrude less than the bent surface 211 of the lower part 223 in the direction of the first radiating part 201.

In one embodiment, the first support part 219 is formed integrally with the lower part 217 of the first radiating part 201, and the second support part is also formed with the lower part 223 of the second radiating part 203. (225) is formed as a whole.

The first support portion 219 supports the first radiating portion 201, helps isolate and block signals between single radiation elements, and is independent of the signal radiating function of the first radiating portion 201. Likewise, the second support portion 225 supports the second radiating portion 203, helps isolate and block signals between single radiation elements, and is independent of the signal radiation function of the second radiating portion 203. . Therefore, in manufacturing the radiation element of the present invention, the first and second radiating parts can be manufactured to have conductive properties, and the first and second support parts can be manufactured to have insulating properties.

In one embodiment, an excitation portion 240 is formed between the first support portion 219 of the first radiating portion 201 and the second support portion 225 of the second radiating portion 203, and the excitation portion 240 ), the slot gap L9 formed on the surface connected to the stepped slot 237 is formed as narrow as 1.2 mm. Although not shown, a feed portion is formed so that electromagnetic energy transmitted along the feed line can be transmitted to the stepped slots 237 and 235 whose width gradually increases. Therefore, when external electromagnetic energy is supplied by the feed line, the excitation unit 240 is excited, and the electromagnetic energy is transmitted to the slots 237 and 235 whose width gradually increases. The transmitted electromagnetic energy is radiated into the air from the ends of the first and second radiating units 201 and 203.

In one embodiment, at the bottom of the first radiating part 201 and the second radiating part 203, an absorber 250 having an absorption rate and an absorption loss rate according to the specifications of the radiating element array structure, and a metal that performs a grounding function The ground 260 is configured sequentially, and a support portion 290 is additionally configured at the bottom of the metal ground 260 to embed the coaxial supply port 270 and electrically/structurally support the single radiation element.

The metal ground 260 is formed as a grounding conductor and can perform a grounding function.

The absorber 250 can effectively block reflected signals among radiated electromagnetic signals that are reflected from points other than the target. The absorber 250 may be configured to absorb general reflected signals (for example, a metal conductive plate).

In one embodiment, the absorber 250 and the metal ground 260 can be formed as one component using a material that has both functions (for example, a conductive grounding plate).

In one embodiment, the metal ground 260 and the absorber 250 are the lower ends of the first radiating part 201 and the second radiating part 203, as shown in FIG. 3, and the first radiating part ( 201) and the second radiating portion 203 can be configured to protrude on both sides with the center. At this time, the protruding length, width, and height are values that can effectively block reflected signals and can be set to optimized values through experimental values.

Referring to FIG. 3, dielectric caps 220 and 230 may be applied to the uppermost part of the single radiation device of the present invention, that is, to the ends of the first radiating part 201 and the second radiating part 203.

The dielectric caps 220 and 230 can minimize the active reflection coefficient of the single radiation element 200 by optimizing the thickness and dielectric constant. That is, by optimizing the thickness and dielectric constant of the dielectric caps 220 and 230 and adjusting the size and phase of the coupling coefficient with nearby array elements, the active reflection coefficient that increases in a specific channel can be minimized.

In one embodiment, the dielectric caps 220 and 230 may be applied to the ends of the first radiating portion 201 and the second radiating portion 203 in a cap shape at a preset depth.

In one embodiment, the dielectric caps 120 and 130 may be formed to a depth (L10) of 4 mm, a dielectric constant of 2.2, and a thickness of 1 mm.

In one embodiment, the dielectric caps 220 and 230 are chair-shaped ( ) can be achieved. The dielectric caps 220 and 230 have a rectangular parallelepiped shape, and one side may be open. Additionally, a notch 280 may be formed on at least one side of the dielectric caps 200 and 230.

At this time, the notch 280 formed is in the direction from the radiating portion to the dielectric cap and may be formed inside the dielectric cap. The notch 280 acts as a design parameter that varies the dielectric constant of the dielectric caps 220 and 230. Therefore, the width, length, height, etc. of the notch 280 act as design parameters according to capacitive coupling, and are preset to optimized values through a number of experimental processes.

In one embodiment, the notch 280 may be configured to have a shape in which the dielectric caps 220 and 230 are dug out with a width and length of 3 mm. The notch 280 may have a rectangular shape.

Therefore, in order to obtain optimal active reflection coefficient characteristics according to the radiating element array structure implemented in the present invention, the parameters of the dielectric caps 220 and 230 and the characteristic values of the notch 280 of the dielectric caps 220 and 230 are obtained through a number of experimental processes. etc. can be decided.

Figure 4 is a detailed view of a radiation element according to simulation of the present invention. And Figure 5 shows an example of an optimized design structure of a single radiation device.

The single radiation element 200 has a vertical length (L4) of 22 mm including the upper part 215 and the lower part 217 of the first radiating part 201, and the first radiating part 201 and the second radiating part 203 ), the horizontal length (L2) including the support portion 290 at the end of the upper portion 215 of the first radiating portion 201 can be formed to be 58.0 mm. .

The width L3 of the upper slot 235 formed between the first radiating part 201 and the second radiating part 203 is 10.3 mm, and the width L8 of the lower slot 237 is 3.4 mm.

Between the single radiation elements mounted on the radiation element array structure, a slot for isolation between the radiation elements with a width of 0.8 mm and a length (L11) of 36.5 mm is formed, and a first radiation portion 201 and a second radiation portion 203 are formed. ) can be applied to the dielectric caps 220 and 230.

The dielectric caps 220 and 230 can be formed to a depth of 4.0 mm (L10), have a dielectric constant of 2.2, and have a thickness of 1 mm.

The horizontal length (L5) of the upper part 221 of the second radiating part 203 is 4.2 mm, the vertical length (L6) of the upper part 221 is 11.5 mm, and the horizontal length (L7) of the lower part 223 is 7.65 mm. mm.

And when constructing the radiating element array structure of the 13 * 13 sub-array shape shown in FIG. 7, as shown in FIG. 8, between each single radiating element, there is a 0.8 mm width and 36.5 mm length (L11). By forming the slit structure 310, the active reflection coefficient can be optimized by isolating single radiation elements.

In addition, at least one side of the dielectric caps 220 and 230 shown includes a notch 280 area, and the notch 280 is 3.0 mm long and 3.0 mm each, and can be formed by digging out the dielectric cap into a rectangular shape.

Other parameters for optimizing the active reflection coefficient of the single radiation element are as shown in FIG. 5.

Figure 6 shows a structural diagram of a radiation element according to an embodiment of the present invention.

Referring to FIG. 6 , the radiation element 200 may form a step 253 at the end of the first radiating portion 201 where the dielectric cap 220 is applied. That is, in order to prevent the overall volume of the radiation element array structure from expanding due to the dielectric cap 220 applied to the first radiating portion 201 and to apply the dielectric cap 220 with a certain thickness, the first radiating portion 201 ) The end portion may have a step 253 of a certain depth.

Additionally, the radiation element 200 may form a step 255 at the end of the second radiation portion 203 where the dielectric cap 230 is applied. That is, in order to prevent the overall volume of the radiation element array structure from expanding due to the dielectric cap 230 applied to the second radiating portion 203, and to apply the dielectric cap 230 with a certain thickness, the second radiating portion 203 ) The end portion may have a step 255 of a certain depth.

Referring to FIG. 6, the left side shows the single copy device 200 with steps 253 and 255 before applying the dielectric cap, and the right side shows the single copy device 200 with the dielectric caps 220 and 230 applied. there is.

As mentioned earlier, the thickness and dielectric constant of the dielectric cap are parameters applied to optimize the active reflection coefficient, so the steps 253 and 255 formed in the first and second radiating parts can be determined according to the thickness of the dielectric caps 220 and 230. there is.

As shown in FIG. 7, the radiation element array structure according to an embodiment of the present invention may linearly arrange a plurality of single radiation elements 200 in the vertical direction. Alternatively, a plurality of single radiation elements 200 may be linearly arranged in the horizontal direction. At this time, the number of single radiating elements 200 arranged is linearly arranged in the horizontal direction or (and) linearly arranged in the vertical direction by the number set according to the antenna specifications (or specifications of the radiating element array structure) applied to the AESA radar system. You can. At this time, the radiation element 200 may be arranged on top of a support structure (not shown) that supports the radiation element array structure as a whole. Additionally, a transmission/reception module that transmits and receives signals through each radiation element 200 may be mounted on the back of the radiation element array structure.

Referring to FIG. 7, it shows a radiation element array structure composed of a 13*13 sub-array shape. Referring to FIG. 7, a structure is formed by linearly arranging 13 single radiation elements in the vertical direction, and 13 arranged structures are arranged in the horizontal direction to form a 13 * 13 sub-array shape.

Figure 8 shows a structural diagram of a radiation element arrangement according to an embodiment of the present invention. Referring to FIG. 8, two single radiation elements are integrated into one piece, and a slit structure 310 is formed between the single radiation elements to isolate the single radiation elements. In the illustrated configuration, two single radiation elements are configured as an integrated structure, but in the case of the 13*13 array configuration of FIG. 7, 13 single radiation elements can be linearly arranged to form an integrated structure.

The single radiation element 300 configured at this time includes first and second radiating units, a dielectric cap 320 applied to the end of the first radiating unit, a dielectric cap 330 applied to the end of the second radiating unit, and a single radiation unit. It is implemented as a slit structure 310 that isolates the elements 300. And at the lower end of the first and second radiating parts, a support part containing a metal ground and a coaxial port is formed.

Figure 9 shows a structural diagram of a single radiation device according to an embodiment of the present invention. The illustrated radiation element 600 has the same overall configuration as the radiation element shown in FIG. 3, but integrally forms a support body 650 that includes all the functions of an absorber, a metal ground, and a support part and provides electrical/structural support. there is. A coaxial port 660 is built into the support 650 to make an electrical connection with the power feeder.

Figure 10 is a structural diagram of WAIM additionally applied to the front of a single radiation element according to an embodiment of the present invention. Figure 11 is a left cross-sectional view of a single radiation device applying WAIM according to an embodiment of the present invention.

Referring to FIG. 10, the radiating element array structure according to an embodiment of the present invention may apply a Wide Angle Impedance Matching (WAIM) structure, which is a dielectric layer, to the entire surface of the single radiating element 200.

That is, the present invention applies the WAIM structure 400 additionally to the front of the single radiation element 200, which basically consists of an optimized step flare notch arrangement.

The WAIM structure 400 can additionally optimize the active reflection coefficient through the preset dielectric constant, thickness (M2), and distance from the radiation element (M1) determined from experimental values. As an example, the WAIM structure may have a dielectric constant of 2.2, a thickness of 2.0 mm (M2), and a distance of 3.0 mm from a single radiating element (M1).

The WAIM structure 400 can be formed in various forms. For example, a plurality of perforated holes may be formed in the WAIM structure. In one embodiment, the WAIM structure may be formed to resemble the shape of a security window.

In one embodiment, the WAIM structures may be individually placed on the front of a single radiating element. In one embodiment, the WAIM structure may be arranged as an integrated structure on the front surface of a radiation element array structure including a plurality of single radiation elements. In one embodiment, the WAIM structure can be placed in front of the antenna using a separate structure from the radiation element array structure.

In general, as the dielectric constant of the WAIM structure increases, the loss of the radiation element may increase. Therefore, the WAIM structure 400 applied in the present invention can further improve the active reflection coefficient without performance deterioration by selecting an appropriate preset dielectric constant and optimizing the distance (M1) and thickness (M2) with the radiation element.

Figure 12 is a schematic configuration diagram of an AESA radar system applying a radiation element array structure according to an embodiment of the present invention.

The AESA radar system 500 of the present invention includes a radiating element array 510 having a radiating element array structure shown in FIG. 1, a plurality of transmitting and receiving modules each corresponding to a plurality of single radiating elements included in the radiating element array, and a plurality of transmitting and receiving modules. In order to minimize the active reflection coefficient that increases in a specific channel when transmitting a signal through a module, a dielectric cap is applied to the end of the radiating part of a single radiating element, and the thickness and dielectric constant parameters of the dielectric cap are optimized to It may include a control module 530 that adjusts the size and phase of the coupling coefficient.

The control module 530 can adjust the size and phase of the coupling coefficient with adjacent radiation elements by optimizing the length and width of the slot structure applied between the plurality of single radiation elements included in the radiation element array structure. The control module 530 can apply WAIM to the front surface of a single radiation element included in the radiation element array structure and optimize the thickness and dielectric constant parameters of the WAIM to adjust the size and phase of the coupling coefficient with adjacent radiation elements.

In one embodiment, the radiation element array 510 is equipped with a radiation element array 510 on one side and a transmission/reception module corresponding to each single radiation element on the opposite side, and transmits a transmission signal provided from each transmission/reception module. Can be radiated through a radiation element.

The control module 530 may be equipped with a beam steerer function. The control module 530 can individually beam control a plurality of transmitting and receiving modules included in the radiation element array 510.

In addition, the AESA radar system 500 transmits a signal through the radiation element array 510 and includes a signal processing module 520 that processes the transmission and reception signals received through the radiation element array 510. The signal processing module 520 can exchange necessary information when transmitting and receiving signals through the control module 530 and the radiation element array 510.

As described above, a plurality of single radiating elements included in the radiating element array structure according to an embodiment of the present invention are optimally designed to minimize the active reflection coefficient in the antenna structure applied to the AESA radar system.

Next, we will look at the simulation results applying an embodiment of the present invention.

In the simulation, the S-parameters of the subarray structure were extracted and mathematically synthesized using CST's MWS, and the active reflection coefficients according to frequency and beam steering angle were compared.

Referring to FIG. 13, if the output a _N of the N-th TRM is referred to as S _{N, N,} and the component that is self-reflected through the N-th antenna is referred to as S N, M, then the N-th antenna is referred to as S _{N, M.} The total reflection component b _N coming to the port can be expressed in [Equation 1] as follows.

[Equation 1]

Finally, the active reflection coefficient at the Nth port is defined as [Equation 2] and [Equation 3].

[Equation 2]

[Equation 3]

Assuming the same TRM output, the active reflection coefficient becomes a function of frequency as shown in [Equation 4], and the equation considering the beam steering angle appears as [Equation 5].

[Equation 4]

[Equation 5]

The active reflection coefficient changes continuously during AESA system operation. Therefore, simulation verification extracts S _{N, M} values from all output ports through CST's MWS, and predicts the maximum and average values of the active reflection coefficient according to frequency and beam steering angle through mathematical calculations based on [Equation 5]. You can.

In order to verify the active reflection coefficient performance in an embodiment of the present invention, the array spacing of the applied X-band array structure was determined as shown in FIG. 14 by considering the wavelength length according to frequency.

The array element according to an embodiment of the present invention has a step flare notch structure that allows for mutual coupling and miniaturization design. The single radiating element of the present invention minimizes the amount of coupling with adjacent elements when the radiating part is arranged in a step shape, and it is easy to minimize the total length of the radiating element.

The single radiating element according to an embodiment of the present invention supplies power through a balun structure, has a mutual coupling and miniaturization effect due to the step shape, and a dielectric cap is applied to the end of the radiating element to optimize the active radiation coefficient. Isolation slots were formed between single radiation elements, and WAIM was applied to the front of the radiation elements. In other words, it is basically a structure in which WAIM is additionally applied to the front of a single radiation element with an optimized active reflection coefficient.

This structure makes it easy to control the amount of coupling between transmission and reception of all array elements. Additionally, the active reflection coefficient of a single radiation element can be optimized by adjusting the phase of the channel-based self-reflection coefficient and mutual coupling coefficient. Additionally, the active reflection coefficient can be minimized by adjusting the phase of the mutual coupling coefficient to maintain a 180-degree phase difference from the self-reflection coefficient.

Figure 15 is an example performance comparison of the active reflection coefficient obtained through a radiation element array structure according to an embodiment of the present invention.

For the simulation of the present invention, a 13*13 sub-array shape radiating element array structure was implemented, and the performance of the active reflection coefficient was compared in the X-band band (8.5 ~ 9.6 GHz) and ±45° beam steering angle. That is, the simulation was performed based on the central element of the 13*13 structure, and the S-parameter values of all elements based on the central element were extracted.

The self-reflection coefficient and mutual coupling coefficient based on the central radiating element can be calculated as the active reflection coefficient through [Equation 4] and [Equation 5]. At this time, the active reflection coefficient values according to frequency and beam steering angle could be obtained as shown in FIG. 15. Figure 15 is the result of calculating the maximum value at all beam steering angles within the calculated beam steering range of 45° within the design frequency band.

As shown in Figure 15, the active reflection coefficients obtained when WAIM is not applied (solid line) and when WAIM is applied (dotted line) are compared. It can be seen that the active reflection coefficient is significantly lower in the case where WAIM is applied (dotted line) compared to the case where WAIM is not applied (solid line).

Basically, the active reflection coefficient of the optimized single radiation element showed a performance improvement of up to 3.6dB based on the maximum value within the simulation frequency band depending on the presence or absence of WAIM.

In order to more visually examine the active reflection coefficient performance according to beam steering, the results according to all beam steering were confirmed.

Figure 16 is a case where WAIM is applied, and Figure 17 is an example of beam steering results when WAIM is not applied.

Referring to Figure 16, it shows the active reflection coefficient simulation results for each Azinuth, Elevation 45° beam steering angle.

Overall, the improvement in active reflection coefficient performance can be confirmed, and it can be seen that the improvement in active reflection coefficient performance is especially effective in Boresight. In this way, improvement in the performance of the active reflection coefficient can promote stable operation of the system to which the array antenna is applied.

In the present invention, performance improvement can be achieved by applying dielectric caps and slots in the X-band radiation element array structure, and additional active reflection coefficient performance improvement effects can be confirmed by applying the WAIM structure. In particular, an improvement in active reflection coefficient performance of up to 3.6 dB was confirmed within the desired beam steering range, and when this improved array antenna structure is applied to the AESA radar system, the shadow area that may occur when operating the AESA transmission beam is minimized and the It is possible to operate the system.

Although the technical idea of the present invention has been described through some embodiments and examples shown in the accompanying drawings, it does not depart from the technical idea and scope of the present invention that can be understood by a person skilled in the art to which the present invention pertains. It should be noted that various substitutions, modifications and changes may be made within the scope. Furthermore, such substitutions, modifications and alterations are intended to fall within the scope of the appended claims.

100,200,300: single radiation element, 101,201: first radiating part, 103,203: second radiating part, 110,310: slit structure, 120,130,220,230: dielectric cap, 250: absorber, 260: metal ground, 270: coaxial port, 280: notch, 290: Support part, 400: WAIM structure

Claims (21)

As a radiation element array structure,
First radiation section;
a single radiating element comprising a second radiating portion; and
It includes a radiating element array arranged in a plurality of preset numbers according to the radiating element array specification to form a single radiating element composed of first and second radiating units,
A dielectric cap having a preset thickness and dielectric constant is applied to the ends of the first and second radiating parts of the single radiation element,
A WAIM structure with a preset thickness and dielectric constant is applied to the front of the single radiation element,
The dielectric cap is a radiating element array structure that is applied to the ends of the first and second radiating parts in a capped shape at a preset depth. In claim 1,
A radiation element array structure in which a plurality of single radiation elements included in the radiation element array are linearly arranged in the horizontal direction. In claim 1,
A radiation element array structure in which a plurality of single radiation elements included in the radiation element array are linearly arranged in the vertical direction. delete In claim 1,
The dielectric cap is shaped like a chair ( ) Radiating element array structure with. In claim 5,
The dielectric cap is a radiation element array structure in which a notch is formed on at least one side of the dielectric cap to the inside of the dielectric cap. In claim 6,
The dielectric cap is a radiating element array structure with a dielectric constant of 2.2 and a thickness of 1.0 mm. In claim 7,
The WAIM structure is a radiating element array structure with a dielectric constant of 2.2, a thickness of 2.0 mm, and a distance of 3.0 mm from a single radiating element. In claim 8,
The single radiating element is a radiating element array structure that forms a stepped slot between the first radiating unit and the second radiating unit. In claim 9,
A stepped slot is a radiation element array structure composed of a stepped notch shape that rises upward. The method of claim 10, wherein the stepped slot is
an upper slot formed on the upper side of the first radiating part and the second radiating part;
It includes a lower slot formed on the lower side of the first radiating part and the second radiating part,
The width of the upper slot is 10.3mm,
Radiation element array structure where the width of the lower slot is 3.4mm. The method of claim 11, wherein the first radiating portion and the second radiating portion are
A radiation element array structure composed of a shape that is symmetrically shifted in the horizontal direction. In claim 12,
The first radiating part consists of an upper part where radiation occurs, a lower part extending below the upper part, and a first support part extending below the lower part to support the upper and lower parts,
A radiation element array structure in which the upper, lower, and first support parts are integrally formed. In claim 13,
The second radiating part consists of an upper part where radiation occurs, a lower part extending below the upper part, and a second support part extending below the lower part to support the upper and lower parts,
A radiation element array structure in which the upper, lower, and second support parts are integrally formed. In claim 14,
A radiation element array structure including a power feeder for feeding power between the first support portion of the first radiation portion and the second support portion of the second radiation portion. In claim 15,
A radiating element array structure in which an absorber with an absorption rate according to the radiating element specifications and a metal ground that performs a grounding function are sequentially formed at the bottom of the first radiating part and the second radiating part. In claim 16,
A radiation element array structure in which a coaxial port is built into the bottom of the metal ground and a third support unit is formed to electrically and structurally support a single radiation element. The method of claim 17, wherein the radiation element array structure is
Radiating element array structure consisting of a 13*13 subarray structure. The method of claim 18, wherein the radiation element array structure is
Radiating element array structure operating in the X-band band (8.5 - 9.6 GHz). The method of claim 19, wherein the single radiation element is
The vertical length including the upper and lower parts of the first radiating part is 22 mm,
The horizontal length including the first radiating part and the second radiating part is 18.7 mm,
A radiation element array structure in which the total vertical length of a single radiation element including from the top of the first radiation portion to the bottom of the third support portion can be formed to be 58.0 mm. A radiation element array having a radiation element array structure according to any one of claims 1 to 20;
A plurality of transmitting and receiving modules each corresponding to a plurality of single radiation elements included in the radiation element array;
In order to minimize the active reflection coefficient that increases in a specific channel when transmitting a signal through a plurality of transmitting and receiving modules, the thickness and dielectric constant parameters of the dielectric cap applied to the ends of the first and second radiating portions of the single radiation element are optimized. do,
A control module that optimizes the parameters of the thickness, dielectric constant, and distance from the radiation element for the WAIM structure applied to the front of the first and second radiation elements of a single radiation element, and adjusts the size and phase of the coupling coefficient with adjacent radiation elements. AESA radar system including.