KR102297437B1 - broadband jamming signal transmission antenna - Google Patents

Abstract

Disclosed is an antenna for transmitting broadband jamming signals. Some conductive patterns of array elements of a banyan tree antenna divided into left and right sides by an inclined slot are formed on a dielectric substrate. A plurality of array elements formed in this manner are arranged and installed on a ground plane to be erected toward an outer side. One conductive pattern corresponding to a ground fin is connected to the ground plane by a ground post and a first shorting post. The other conductive pattern corresponding to an excited fin has a feed post separated from the ground and coupled to a feed line, and a second shorting post extending to the ground plane and electrically connected. One or more slots are formed on the outer edge of the conductive pattern of the array elements divided into the left and right sides. At least one director formed as a double ring-shaped conductive pattern is installed in an inclined-slot area. Therefore, the antenna can significantly improve the gain characteristics, efficiency, and performance of the antenna without changing the existing manufacturing process and significantly increasing costs.

Description

Broadband jamming signal transmission antenna

The present invention relates to a broadband jamming signal transmission antenna, and more particularly, it is used in an electronic-only electronic attack system mounted on a military platform such as a fighter, a ship, etc. to prevent the detection of the position of the platform on which the system is mounted from the enemy's radar. It relates to a wideband jamming signal transmitting antenna that can be used for electromagnetic disturbance.

In modern weapon systems, many of them are electronic, and in many cases, they use electronic sensing equipment at a remote location to recognize opponents, attack, and defend. Therefore, electronic warfare forms a core part of modern warfare.

Electronic warfare refers to activities that determine, reverse exploit, or neutralize the electronic spectrum used by the enemy while protecting the power of friendly forces or all military activities that use electromagnetic and directed energy to control the electronic spectrum of the enemy.

These electronic warfare activities largely include electronic attack (ECM) that neutralizes the opponent's radar or jamming equipment, electronic support (ESM: Electronic Support Measure) that intercepts radio waves transmitted from jamming equipment or detection equipment and converts them into information, and the enemy's ECM. It can be divided into three categories: Electronic Counter-Counter Measures (ECCM), which protects friendly information, detection, and jamming equipment from ESM, and jamming is an electronic attack among them.

Electromagnetic attack (ECM) is the act of obstructing the enemy's monitoring, attack, and communication activities, such as by emitting electromagnetic waves in a band similar to that of the enemy's radar to neutralize them, or by creating virtual images on the radar to interfere with physical attacks or disrupt communication. is commonly referred to as jamming. Jamming may be performed in the form of a disturbance that makes it difficult to use a specific frequency radio wave by radiating radio frequency (RF) energy, or a form of deception that transmits false information.

The purpose of jamming in the early stages of an electronic attack is to disrupt, weaken, and deceive the kill chain, which is a series of procedures necessary for the enemy to attack friendly aircraft.

As shown above, since jamming is performed through high-frequency energy radiation, a transmitter as a high-frequency radiator to perform this operation, that is, an antenna is required. In order to properly jamming, an antenna suitable for the characteristics of an electronic attack in electronic warfare is required, and in any case, an antenna capable of increasing efficiency or gain is required.

For example, an antenna used in a jamming transmission system needs to have wideband characteristics in order to cope with this situation as a whole because the enemy's radar operating frequency can be used in various ways.

As the conventional wideband transmission antenna, a wideband horn antenna as shown in FIGS. 1 and 2 , a Log Periodic Dipole Antenna (LDPA), or the like may be used.

However, the conventional jamming transmission antenna basically derives broadband characteristics, but the size of the antenna is too large to be used as an array element or element in an array antenna applied to realize high-gain characteristics of a jamming transmission system. have. More specifically, the horn antenna has a disadvantage that it is bulky and a manufacturing process is complicated, and the LPDA has a problem that it is bulky and has poor durability.

In particular, when manufacturing an antenna for jamming transmission as one of the fighter avionics equipment that is frequently requested and used in recent years to increase survivability and implement multifunctionality, reducing the size of the antenna can be the most important factor. Horn antennas and LDPAs are not suitable for use as an array element or an array element of such an antenna.

A broadband array element widely used in array antennas in recent years is the Vivaldi antenna, also called "taper slot antenna", first proposed by Gibson in 1979 (PJ Gibson, "The Vivaldi Aerial", Proc. 9th European Microwave Conference) , 1979, pp. 101-105.). The element consists of a flared slot structure that has been extensively studied from the ground up, and is known for its excellent wideband scan performance, achieving greater than 10:1 bandwidth, and direct connection to standard RF interfaces.

However, these Vivaldi antenna array elements have two major drawbacks. The elements are still large, and the operating band is usually several wavelength bands in size for high performance, which lacks common mode support, and the electrical connection between adjacent elements is required for good performance, making modular fabrication difficult.

An improved version of the Vivaldi antenna is the Antipodal Vivaldi Antenna (AVA) introduced by Gazit in 1988 (E. Gazit “Improved design of the Vivaldi antenna,” Proc. IEEE Microw., Antennas Propag., vol. 135, pp. 89, 1988). AVA consists of microstrip lines that are converted to slot line structures with exponential tapers. This element can achieve high cross-polarization levels due to the offset pin.

A new improvement with the addition of a third pin is the Balanced Antipodal Vivaldi Antenna (BAVA) introduced by Langely, Hall and Newman. (JD Langely et al, “Balanced Antipodal Vivaldi Antenna for wide bandwidth phased arrays,” IEEE Proceeding of Microwave and Antenna Propagations, Vol. 143, No. 2 Apr. 1996, pp. 97-102.).

Recently, Elsallal and Schaubert performed extensive numerical studies to understand and improve the performance of BAVA elements in double and single polarization arrays. (MW Elsallal and DH Schaubert, “Parameter Study of Single Isolated Element and Infinite Arrays of Balanced Antipodal Vivaldi Antennas,” 2004 Antenna Applications Symposium, Allerton Park, Monticello, Ill., pp. 45-69, 15-17 September 2004. I.) and (MW Elsallal and DH Schaubert, “Reduced-Height Array of Balanced Antipodal Vivaldi Antennas (BAVA) with Greater than Octave Bandwidth,” Antenna Applications Symposium, Allerton Park, Monticello, Ill., pp. 226-242, 2005 September 21-23.). This study reveals an impedance anomaly that occurs across the desired band, which greatly limits the bandwidth of the array. Their work was published in US Patent Application Publication 200802111726 (DmBAVA-MAS) and in a doctoral dissertation (MW Elsallal, "Doubly-Mirrored Balanced Antipodal Vivaldi Antenna (DmBAVA) for High Performance Arrays of Electrically Short, Modular Elements", Electrical and Computer Engineering, Univ. of Massachusetts, February) provide a solution with sufficient control over anomalies for bandwidth improvement, such as mirroring elements in the E (electric field) and H (magnetic field) planes and placing slots in the pin layer.

A development similar to BAVA is the Bunny Ear developed by J. J Lee (Lee, JJ, et al., "Wide Band Bunny-Ear Radiating Element," Antennas and Propagation Society International Symposium, AP-S Digest, pp). ) in the form of a radiating element (USP 5,428,364). The element consists of a dielectric slab printed on each side with a tapered slot line that transitions from a narrow slot in the ground plane to a wider slot in the radiating hole. The ground plane of the slot line is pin-shaped, with a narrow pin in the ground plane and a wide pin in the hole. This element achieves a wide bandwidth, is low in height and is modular, but requires a balun to be built into the element to increase manufacturing cost and complexity.

Figure 3 is a view showing together the front and side of the array element according to an embodiment of the Banyan tree antenna (Banyantree antenna).

Array element pattern for transmitting signal radiation is similar to rabbit ear shape, Banyan Tree antenna has excellent broadband characteristics, is naturally smaller in volume than horn antenna or LPDA, and D-dual polarization is easy to implement. It has advantages and is suitable for use as a jamming signal transmission antenna for miniaturized devices.

The characteristics of such an antenna are affected by a function defining an upper curve (inner curve) and a lower curve (outer curve), respectively denoted by Ri and Ro of the leaf-shaped conductor pattern constituting the individual array elements, The function f(x) of the curve connecting the lower P ₁ (x ₁ , y ₁ ) point of the _{gradient slot to the upper P 2} (x ₂ , y _{2 ) point can be given as the following equation.}

f(x)= C ₁ e ^Rx + C ₂

In this case, C ₁ =(y ₂ -y ₁ )/(e ^rRx2 -e ^Rx1 ),

C ₂ =(y ₂ e ^Rx2 -y ₁ e ^Rx1 )/(e ^Rx2 -e ^Rx1 ).

However, this type of antenna still has room for improvement in performance such as gain characteristics of individual array elements, and a layered structure in which a conductive pattern is covered with a dielectric substrate back and forth may be cumbersome and complicated to manufacture.

US 20110057852 A1 : modular wideband antenna array

The Banyan Tree Antenna Array (by Steven S. Holland, Student Member, IEEE, and Marinos N. Voubakis, Member, IEEE, IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 59, NO 11, NOVEMBER 2011)

An object of the present invention is to provide a compact wideband electronic warfare jamming signal transmitter having a simple configuration and a smaller size compared to the conventional jamming antenna described above, and having improved gain characteristics.

Another object of the present invention is to provide a wideband compact electronic warfare jamming signal transmitter having a configuration that is simple in manufacturing and can reduce costs.

The present invention for achieving the above object

The conductive pattern of the array element of the Banyan Tree antenna, which is separated on both left and right sides by an inclined slot that decreases in width from the upper center to the lower part, is formed on a dielectric substrate as a conductive film through conductive layer printing, etc., and a plurality of array elements of the Banyan Tree antenna is arranged and installed in a form standing outward from the ground plane, and the separated conductive pattern has an upper curve defined by an inclined slot, and is spaced apart from the ground post and the ground post extending from the conductive pattern to the ground plane Electrically connected to the ground by a first shorting post extending from the pattern to the ground plane, the separated other conductive pattern has an upper curve defined by an inclined slot, and extends from the conductive pattern toward the ground plane but is connected to the ground In the broadband jamming signal transmission antenna having a feed post separated and coupled to a feed line, and a second short post spaced apart from the feed post and electrically connected to the ground plane from the other side pattern,

In the conductive pattern formed through the conductive layer printing, etc., in order to derive broadband characteristics, horizontally or at a certain angle with the horizontal Branches are formed with one or more slots or notches,

At least one director composed of a double ring-shaped conductive pattern is installed in the inclined slot (upper middle of the two conductive patterns).

In the present invention, a plurality of directors may be arranged in the vertical direction, and the double ring ring may be a square ring or other polygonal closed curve in addition to a circular ring.

In the present invention, a plurality of antenna array elements may be arranged in a matrix form on a ground plane.

According to the present invention, in manufacturing a transmission antenna for jamming, efficiency and performance can be increased by improving gain characteristics while having a simple configuration and small size.

According to the present invention, it is possible to have the effect of significantly improving the efficiency and performance of the jamming signal transmitting antenna while hardly changing the existing manufacturing process and not significantly increasing the cost.

In the present invention, in particular, the array element of the leaf-shaped Vivaldi antenna or the Banyan Tree antenna has a broadband characteristic even though it is miniaturized by adding a double-ring-shaped director and a slot formed in the conductive pattern, and in particular, in the broadband frequency band of 2 to 6 GHz, 0 It should have a gain characteristic of more than dBi. In addition, by disposing these individual array elements in a matrix form, it can be extended to an array antenna to have high gain characteristics.

1 and 2 are conceptual diagrams showing a horn antenna (HORN ANTENNA) and an LPDA, respectively, as examples of a transmission antenna for jamming having a conventional wideband characteristic;
Figure 3 is a view showing together the front and side of the array element according to an embodiment of the Banyan tree antenna (Banyantree antenna).
4 is a conceptual perspective view illustrating a transmission antenna array element for jamming according to an embodiment of the present invention;
5 is a gain characteristic graph showing a front-direction gain in a certain frequency section in the embodiment as in FIG. 4;
Figure 6 is a graph showing the change in the magnitude of the reflection coefficient in a certain frequency section in the embodiment as in Figure 4;
7 to 11 are graphs showing the change in the radiation size or the radiation pattern with respect to the azimuth change in the two-dimensional plane at each frequency of 2 to 6 gigaheltz;
12 is a graph showing a relationship between a gain and a frequency that varies according to the size of a gap between two conductive patterns;
13 is a graph showing a relationship between a frequency and a reflection coefficient that varies according to the size of a gap between two conductive patterns;
Figure 14 and Figure 15 is a graph showing the relationship between the outer curve (lower curve), the slope (r _o) of the relationship between the frequency and the gain changing in response to changes in the frequency and the reflection coefficient of the conductive pattern,
16 and Fig. 17 is a graph showing the relationship between the inside curve of the conductive pattern (upper curve) slope (r _i), the frequency and the gain and frequency relationship between the reflection coefficient which changes in accordance with change in,
18 and 19 are graphs showing the relationship between the changing frequency and the gain and the relationship between the frequency and the reflection coefficient when a double-ring director arranged vertically in the inclined slot between the conductive patterns is installed;
20 and 21 are respectively state comparison diagrams showing the state of the existing Banyan Tree antenna array element and the electric field formation state when the antenna array element is driven according to an embodiment of the present invention;
22 is a structural conceptual diagram showing a state in which the antenna array elements of the present invention are installed in an 8*8 matrix form on a ground substrate;
23 and 24 are comparative diagrams showing the magnitude of the gain for each azimuth when two directions are oriented according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail through specific examples with reference to the drawings.

4 is a conceptual perspective view illustrating a transmission antenna array element for jamming according to an embodiment of the present invention.

The rectangular dielectric substrate 10 corresponds to the radiating dipole of the array element of the Banyan Tree antenna (broadly Vivaldi antenna) separated on both sides by a tapered slot 15, which decreases in width from the top to the bottom in the center. Conductive patterns fins 21 and 23 are formed by printing or the like to form an array element.

The array elements of such a Banyan Tree antenna are installed in a form that stands outward from the ground plane. One conductive pattern (grounded fin: 21) separated by a gap (g) in the middle extending from the lower end of the inclined slot has an upper curve (inner curve) defined by the inclined slot, and in this conductive pattern 21, the ground plane ( 50) and electrically connected to the ground by a first shorting post (33) spaced apart from the ground post and extending from the one conductive pattern to the ground plane.

The other conductive pattern (excited fin: 23) separated by a gap has an upper curve defined by a tapered slot: 15, and extends from the conductive pattern 23 toward the ground plane 50, but is electrically separated from the ground A second shorting post (shorting) which is spaced apart from the feeding post (35) and coupled to the standard RF interface (standard RF interface) and is electrically connected by extending from the other side pattern to the ground plane. post: 37).

The form of feeding and grounding of these conductive patterns is different from that of a general Vivaldi antenna, and by integrating the balance unbalance control function in the array element, it can contribute to simplifying the overall antenna structure and reducing the size of the antenna for radio wave radiation.

The parameter values in the array elements shown in Fig. 4 can be given as in the following table.

In addition, in this embodiment of the present invention, unlike the array elements constituting the conventional Banyan Tree antenna, the conductive pattern has a plurality of narrow-width slots, each having a horizontal and constant angle on both left and right edges to derive a broadband characteristic, in this case, five slots. (slot: 25) is formed, and three directors 40 having a double ring-shaped conductive pattern are installed in an inclined slot between both conductive patterns to be arranged vertically. A double ring-shaped director 40 is inserted into a portion forming an inclined slot in the middle of the conductive pattern and a plurality of slots are formed on both left and right sides of the conductive pattern in order to improve gain.

For example, it can be seen that the double ring acts as a resonator to guide and reinforce the direction of electron radiation toward the center line where the double ring is installed. It can be seen that by weakening the electron radiation to the periphery, it plays a role of concentrating the electron radiation relatively toward the center.

Here, the array element of the antenna is a Duroid substrate and uses a dielectric constant ε _r = 2.2 and a loss tangent tanδ = 0.0035, and the conductive pattern forming the array element of the leaf-shaped Vivaldi antenna or Banyan tree antenna is printed through It consists of a conductive pattern of a thick film.

FIG. 5 is a gain characteristic graph showing a front gain in a predetermined frequency section in the embodiment shown in FIG. 4 , and FIG. 6 is a graph showing a change in the magnitude of a reflection coefficient in a constant frequency section in the embodiment shown in FIG. 4 .

Referring to these graphs, it can be seen that the antenna of the embodiment has a front-direction gain of -5 dBi or more in the 2-6 GHz frequency band, and the reflection coefficient has a value of about -5 dB or less in the 3-6 GHz band can be checked

7 to 11 are graphs showing the change in the radiation size or the radiation pattern with respect to the change in the azimuth angle of the two-dimensional plane at each frequency of 2 to 6 gigaheltz.

Here, the solid line represents the case where the two-dimensional plane is taken as the zx plane, and the dotted line represents the case where the two-dimensional plane is taken as the zy plane.

Hereinafter, the effect of each parameter on the gain characteristic and the reflection coefficient of the array element of the present invention will be described.

12 is a graph showing the relationship between a gain and a frequency that varies according to the size of a gap between two conductive patterns, and FIG. 13 is a graph showing a relationship between a frequency and a reflection coefficient that varies according to the size of a gap between two conductive patterns It is a graph.

As shown, as a result of checking the front gain and reflection coefficient by changing the gap (g) between the conductive patterns, the gap is greater than or equal to 0.1mm and less than or equal to 1.0mm when considering low-frequency gain and reflection coefficient matching. It can be seen that it is desirable to select a value.

14 and 15 are graphs showing the relationship between the outer curve (lower curve), the slope (r _o) of the relationship between the frequency and the gain changing in response to changes in the frequency and the reflection coefficient of the conductive pattern.

Wherein sikimyeo change the slope r _o the outer curve of the conductive pattern (the lower curve), the larger the gain the front direction and the results confirm the reflection coefficient, the outer curve slope r _o so that gain reduction is larger at high frequencies r _o value than -1.5 It can be seen that it is desirable to select a value greater than or equal to -0.4 and less than or equal to -0.4.

16 and 17 is a graph showing the relationship between the inside curve (the upper curve) slope (r _i) Relationship between the frequency and the gain changing in response to changes in the frequency and the reflection coefficient of the conductive pattern.

where the slope of the inner curve of the conductive pattern r _i A change sikimyeo to the front direction of the gain and the check result of the reflection coefficient, the bandwidth gain of the low frequency with more than 0 dBi can be seen that it is preferable r _i is designed to have a less than or equal to 0.2.

18 and 19 show the relationship between frequency and gain and frequency and reflection when a double ring director arranged vertically in an inclined slot between conductive patterns is installed, a slot is installed, and a short post is installed. It is a graph showing the relationship between coefficients.

From the above drawings, it can be seen that the gain of the frequency band after 4.5 gigahels can be improved by adding a double ring director, and the reflection coefficient matching of -10dB or less is improved through the slots and short posts on both edges of the conductive pattern. know you can do it.

20 and 21 are respectively state comparison diagrams showing an electric field formation state when the conventional Banyan Tree antenna array element and the antenna array element according to an embodiment of the present invention are driven at 5 gigahels.

As a result of checking the electric field distribution in the presence and absence of the slot and the double ring director, it can be seen that the electric field strength becomes stronger in the presence of the slot and the reducing director.

22 is a conceptual diagram showing a state in which the antenna array elements of the present invention are installed in an 8*8 matrix form on a ground substrate, and FIGS. It is a comparative diagram showing the gain size for each direction.

It was confirmed that the front gain of steering at azimuth φ = 0 and elevation angle θ = 0 was 24.3 dBi at 3 GHz, and 23.4 dBi when steering at φ = 0 and θ = 30 degrees. Since the beam steering jamming transmission technique for selectively adjusting the detection direction using the planar array antenna is well known in the art related to the array antenna, a detailed description of the beam steering method will be omitted.

In summary, in the present invention, the present invention uses the same feeding and short-post configuration as the Banyan Tree antenna, and additionally installs a double-ring director, and a conductive pattern (Excited fin, grounded) formed to radiate a jamming signal. By installing slots on both sides of fin), it was confirmed that the antenna efficiency can be increased over a wide frequency band by improving the gain characteristics. It was confirmed that it can be reduced to about -5dB or less in the gigaheltz band, and it can be seen that the front gain can be improved in the array antenna formed by arranging the array elements on the ground plane in a matrix manner.

In the above, the present invention has been described with reference to limited embodiments, but these are only illustratively described to help the understanding of the present invention, and the present invention is not limited to these specific embodiments. For example, the parameters of the embodiment described herein are suitably made when the target frequency band is, for example, 2 to 6 gigaheltz, and when the operating frequency band is changed to 0.5 to 2 gigaheltz, 6 to 18 gigaheltz, and 18 to 40 gigaheltz, the corresponding parameters Array element scale can be increased or decreased by deriving a numerical value. Accordingly, those of ordinary skill in the art to which the present invention pertains will be able to make various changes or application examples based on the present invention, and it is natural that such modifications or application examples belong to the appended claims.

10: substrate 15: tapered slot
21, 23: conductive pattern 25: slot
31: ground post 33: first shorted post
35: feed post 37: second short post
40: director 50: ground plane

Claims (4)

Conductive patterns of the array elements of the Banyan Tree antenna that are separated to the left and right by an inclined slot whose width decreases from the upper center to the lower part are formed on the dielectric substrate, and a plurality of the array elements are arranged in a form that stands outward from the ground plane Among the installed and separated two conductive patterns, one conductive pattern has an upper curve defined by an inclined slot, and a ground post extending from the one conductive pattern to the ground plane and a ground post spaced apart from the ground post are grounded in the one conductive pattern. Electrically connected to the ground by a first shorting post extending in a plane, the other conductive pattern has an upper curve defined by the inclined slot, and extends in the direction of the ground plane from the other conductive pattern. In the broadband jamming signal transmission antenna having a feeding post separated from the ground plane and coupled to the feeding line, and a second shorting post spaced apart from the feeding post and extending from the other conductive pattern to the ground plane and electrically connected,
In the conductive pattern, one or more slots are formed on both left and right edges in order to derive a broadband characteristic, respectively, horizontally or having a predetermined angle with the horizontal,
A wideband jamming signal transmitting antenna, characterized in that at least one double ring director composed of a double ring conductive pattern is installed in the inclined slot area The method of claim 1,
In the array element, a plurality of double-ring directors are arranged in a vertical direction. The method of claim 1,
In the double ring director, the double ring is a wideband jamming signal transmitting antenna, characterized in that it is formed of a polygonal closed curve. The broadband jamming signal transmission antenna according to claim 1, wherein a plurality of array elements are arranged and installed in a matrix form on the ground plane.

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