KR102351449B1 - broadband jamming signal transmission antenna - Google Patents

Abstract

Disclosed is a broadband jamming signal transmission antenna to increase efficiency and performance. According to the present invention, the broadband jamming signal transmission antenna includes a conductive pattern of an array element, which is divided into both left and right sides by an inclined slot having a width gradually decreasing from the upper center to the lower part is formed, formed on one surface of a dielectric substrate and allows a plurality of array elements of such a Vivaldi antenna to be arranged and installed on a ground plane toward the outside, wherein one side of the conduction pattern includes a ground post extending from one conductive pattern to the ground plane; a power supply post electrically connected to the ground by a first matching post extending from the one conductive pattern to the ground plane and having the other separated conductive pattern extending from the other conductive pattern toward the ground plane while being separated from the ground, and a second matching post extending from the other pattern to the ground plane to be electrically connected. The separated conductive pattern comprises: a plurality of slots or notches formed on both left and right edges to extract a broadband characteristic, respectively, horizontally or at a predetermined angle to the horizontal; and a parasitic loop conductive pattern installed on the opposite side of the dielectric substrate.

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 military platforms such as fighters and ships, etc. to prevent the detection of the position of the platform on which this 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 the opponent, 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 information, detection, and jamming equipment of friendly forces from ESM, and jamming is an electronic attack among them.

Electromagnetic attack (ECM) is an 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 a 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 implement a high-gain characteristic of a jamming transmission system. have. That is, 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 weak 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, and In an array antenna to achieve this, a plurality of array elements need to be installed densely by reducing the mutual distance, and for this, individual array elements need to be reduced in size. There are aspects that are unsuitable for use as an array element or array element.

Accordingly, in order to make the array antenna have broadband characteristics, a method for improving bandwidth by inserting a cavity structure or combining antennas with broadband characteristics is sought, and designs are being applied to this, but the wideband antenna is still bulky and manufactured The process is complicated, and even in the case of a Vivaldi antenna, which will be described later, there are disadvantages such as high cost.

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, the array elements of these Vivaldi antennas have two main 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. The 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.

3 is a view showing a front and a side view together of an array element according to an embodiment of a 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 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 where} 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, even with this type of antenna, there is still room for improvement in performance such as gain characteristics of individual array elements, and a form 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 transmitter with improved gain characteristics and a simpler configuration and smaller size than the conventional jamming antenna described above.

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

The present invention for achieving the above object

On one surface of the dielectric substrate, the conductive pattern of the array element of the Vivaldi antenna, which is separated to the left and right by an inclined slot that decreases in width from the top to the bottom, is formed as a conductive film through conductive layer printing, etc., and such an array element of the Vivaldi antenna A plurality of the conductive patterns are arranged and installed in a form that stands out from the ground plane, and the upper curve is defined by an inclined slot of the separated conductive pattern, and the one side is spaced apart from the ground post and the ground post extending from the conductive pattern to the ground plane. The conductive pattern is electrically connected to the ground by a first matching post extending from the conductive pattern to the ground plane, and the separated other conductive pattern has an upper curve defined by an inclined slot, and extends from the conductive pattern toward the ground plane and is extended to the ground. In the broadband jamming transmission antenna having a feed post separated from and coupled to a feed line, and a second matching 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,

A parasitic loop conductive pattern is installed on the opposite surface of the dielectric substrate.

In the present invention, the parasitic loop conductive pattern of the opposite surface may be formed in the form of a square loop covering the upper end and both ends of the conductive pattern of one surface, and in addition to the square, it may form a circle or other polygonal, closed curve shape.

In the present invention, the slot may be formed of a rectangular narrow gap.

In the present invention, a plurality of Vidaldi 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, in the array element of the leaf-shaped Vivaldi antenna or Banyan tree antenna having a matching post, a parasitic loop is further installed on the back side of the substrate, and a plurality of slots are formed at the side ends of the conductive patterns on both sides for the dipole to form a broadband By allowing the frequency range to be covered and high-sensitivity coupling can be made, it has wideband characteristics even though it is miniaturized, and has high gain characteristics, especially in the wideband frequency band of 2 to 6 GHz, and also controls these individual array elements. By arranging a plurality in the width direction and extending it to an array antenna to have a low reflection coefficient or a low voltage standing wave ratio, high efficiency can be achieved in output.

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;
3 is a view showing a front and a side view together of an array element according to an embodiment of a Banyantree antenna.
4 is a conceptual perspective view showing a transmission antenna array element for jamming according to an embodiment of the present invention together with a partially enlarged view showing the characteristics;
Fig. 5 is a rear view showing a parasitic loop formed on the rear surface of the array element of Fig. 4;
6 is a graph showing a front-direction gain measured at several frequencies in a predetermined frequency section and a front-direction gain characteristic curve by simulation in the same embodiment as in FIG. 4;
Figure 7 is a graph showing the change in the magnitude of the reflection coefficient by measurement and simulation in a certain frequency section in the embodiment as in Figure 4;
8 shows the reflection coefficient according to the frequency change by the array element of the Banyan Tree antenna having the matching post, and the reflection coefficient according to the frequency change in each case when a slot is formed in the array module or a rear parasitic loop is formed. comparison graph,
9 is a perspective view showing a state in which a plurality of array elements (modules) of the present invention are arranged in the left and right width directions on a ground substrate;
10 is a conceptual diagram showing that a plurality of array modules are arranged in phase in the width direction similar to FIG. 9;
11 is a graph showing the active voltage standing wave ratio obtained by varying the number of arrays in the array elements in the periphery in the antenna forming the phased array as in FIG. 9 and whether measurement and simulation are performed;
12 is a graph showing the active voltage standing wave ratio obtained by varying the number of array elements in the central part of the antenna constituting the phase array as shown in FIG. 9 and whether measurement and simulation are performed.

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

4 is a conceptual perspective view showing a transmission antenna array element for jamming according to an embodiment of the present invention and an enlarged view of parts thereof, and FIG. 5 is a rear view showing a rear loop of the array element.

Here, the conductive patterns (fins: 21, 23) of the array elements of the Vivaldi antenna separated on the left and right by a tapered slot (15), which decreases in width from the upper center to the lower part, are printed on the rectangular dielectric substrate (10). is formed by the method of the array element is made. The conductive patterns 21 and 23 may be considered to correspond to dipoles for electromagnetic radiation of the antenna.

The array elements of this Vivaldi antenna are installed in a form that is erected outward from the ground plane 50 . An upper curve (inner curve) is defined by an inclined slot 15 or a one-sided conductive pattern (grounded fin 21) separated to the left and right by a gap, and the ground extending from this conductive pattern to the ground plane 50 It is electrically connected to the ground by the post 31 and a first matching post 33 or 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 the inclined slot (15) has an upper curve defined by an inclined slot (tapered slot), and extends from the other conductive pattern (23) toward the ground plane and is electrically separated from the ground. A feed line, for example, a feed post 35 coupled to a standard RF interface, and a second matching post spaced apart from the feed post and extending from the other conductive pattern 23 to the ground plane 50 and electrically connected Or have a matching post or shorting 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.

In addition, in this embodiment of the present invention, unlike the array elements constituting the existing Vivaldi antenna, the conductive pattern separated left and right by the inclined slot 15 has a horizontal and a certain angle on both left and right edges to derive a broadband characteristic, respectively. A plurality, here five narrow, rectangular slots 25 are formed.

In addition, the characteristic parasitic loop 40 formed on the rear surface of the substrate of FIG. 5 is a kind of conductive pattern and may be formed as a conductive film by printing or the like, similarly to the front conductive pattern. Here, the parasitic loop is formed to be symmetrical and balanced with a rectangular conducting wire pattern having a predetermined width covering the top and left and right side ends of the front conductive pattern, but this embodiment does not limit the conditions of the parasitic loop. Therefore, the parasitic loop may have a circular or other polygonal shape or any closed curve shape.

The additional formation of these slots 25 or parasitic loops 40 is to improve the gain.

The parameter values in the array elements shown in Figs. 4 and 5 can be given as in the following table.

Here, the array element of the antenna is a TLY-5 substrate with a relative dielectric constant ε _r = 2.2 and a loss tangent tan δ = 0.0009. is done The substrate is a rectangular plate with a width of 39.4mm, a height of 119mm, and a thickness of 1.6mm.

6 is a graph showing a front-direction gain measured at several frequencies in a constant frequency section and a front-direction gain characteristic curve by simulation in the embodiment shown in FIG. 4, and FIG. 7 is a constant frequency section in the embodiment shown in FIG. It is a graph showing the change in the magnitude of the reflection coefficient by measurement and simulation.

It can be confirmed that the value of the front gain by simulation and direct measurement is greater than -0.6 dBi in the frequency 3 to 6 gigaheltz band, and the reflection coefficient is -10 dB or less in the same 3 to 6 gigaheltz frequency band. can be verified. At this time, the voltage standing wave ratio has a value of 1.5:1 or less at 3 gigaheltz or more.

8 is a reflection coefficient according to a frequency change by an array element of a Vivaldi antenna (Banyan tree antenna) having a matching post, and a reflection according to a frequency change in each case when a slot is formed in the array module or a rear parasitic loop is formed. It is a comparison graph that displays coefficients together.

The fractional bandwidth representing the frequency characteristic is a value obtained by dividing the bandwidth of the frequency curve by the center frequency of the bandwidth, where the fractional bandwidth in the simple conductive pattern formed through printing and the slot in the simple conductive pattern It can be seen that the fractional bandwidth in the additionally formed conductive pattern has values of 12% and 35%, respectively, and the fractional bandwidth in the conductive pattern having the rear parasitic loop is 66%.

9 is a perspective view showing a state in which a plurality of array elements (modules) of the present invention are arranged in the left and right width directions on a ground substrate, and FIG. 10 is a conceptual diagram showing that a plurality of array modules are arranged in phase in the width direction similar to FIG. Reference is made from Pozar's "A relation between the active input impedance and the active element pattern of a phased array" ( IEEE Trans. Antennas Propag. , vol. 51, no. 9, pp. 2486-2489, Sept. 2003). .

In the antenna in which the array elements are phased as shown in FIG. 10 , the total terminal voltage V _n at the N-th element may be given by the following equation.

V _n =V _n ⁺ +V _n ^- =V _n ⁺ +∑S _m V _n ⁺ (where ∑ means the sum of m from 1 to N)

At this time, the active reflection coefficient Γ and the active voltage standing wave ratio (Active VSWR) may be defined by the following equations.

To extend this arrangement, boundary conditions must be established and analyzed to have a periodic structure in the simulation.

11 is a graph showing the active voltage standing wave ratio obtained by varying the number of array elements in the periphery of the antenna constituting the phase arrangement as in FIG. 9 and whether measurement and simulation are performed, and FIG. 12 is the same phase as in FIG. It is a graph showing the active voltage standing wave ratio obtained by varying the number of array elements in the array element in the center of the array antenna and whether measurement or simulation is performed.

It can be seen here that the active voltage standing wave ratio (Active VSWR) increases in the central array element and decreases as the number of array elements increases.

Summarizing through the above drawings and related experimental results, the broadband jamming signal transmission antenna having the array element of the present invention applies the frequency applied through the matching post, the slots installed in the conductive pattern, and the parasitic loop on the back side. It can be confirmed that the bandwidth is extended, and it can be seen that the value of the front-direction gain is greater than -0.6 dBi in the frequency 3 to 6 gigaheltz band under the conditions with the same parameters as in the embodiment, and the reflection coefficient is the same It can be seen that the frequency band is -10dB or less in the 3 to 6 gigaheltz frequency band. At this time, it can be seen that the voltage standing wave ratio has a value of 1.5:1 or less at 3 gigaheltz or more. .

In the above, the present invention has been described through limited examples, but these are only illustratively described to help the understanding of the present invention, and the present invention is not limited to these specific examples.

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 matching post
35: feeding post 37: second matching post
40: parasitic loop 50: ground plane

Claims (5)

A conductive pattern (grounded fin, excited fin) of an array element is formed on one surface of the dielectric substrate, which is separated from left and right by a tapered slot that decreases in width from the top to the bottom in the center, and the plurality of array elements are grounded One conductive pattern (grounded fin) among the separated conductive patterns is arranged and installed to stand outward in a plane. is electrically connected to the ground by a first matching post extending to the ground plane in In the broadband jamming signal transmission antenna having a second matching post spaced apart from the feeding post and extending from the other conductive pattern to the ground plane and electrically connected to the ground,
In the separated conductive pattern, a plurality of slots or notches are formed on both left and right edges, respectively, horizontally or having a predetermined angle with the horizontal in order to derive a broadband characteristic,
A parasitic loop conductive pattern is installed on the opposite surface of the dielectric substrate, and the parasitic loop conductive pattern is formed in a rectangular loop shape covering the upper end and both sides of the conductive pattern on the one surface. delete The method of claim 1,
The parasitic loop conductive pattern is a broadband jamming signal transmitting antenna, characterized in that it is made of a circular wire of a constant width. The method of claim 1,
The slot is a broadband jamming signal transmission antenna, characterized in that formed in a horizontally narrow rectangle in the left and right directions. The method of claim 1,
The plurality of array elements are arranged in a matrix form having at least one column on the ground plane.

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