KR101022359B1 - Structure mutual suppression between elements in array antenna - Google Patents

Abstract

PURPOSE: An array antenna with a mutual coupling suppressing structure is provided to suppress a mutual coupling effect between adjacent antenna devices, thereby increasing antenna performance. CONSTITUTION: The first antenna element(110) is arranged in a fixed Cn row and a fixed R2m-1 column. The second antenna element(120) is arranged on a Cn row and an R2m+1 column. The third antenna element reflects an emitting signal from the first antenna element to the second antenna element and reflects an emitting signal from the second antenna element to the first antenna element. A blocking member has a rectangular thin film shape.

Description

Structure mutual suppression between elements in array antenna

The present invention relates to an array antenna, and more particularly, to an array antenna having a mutual coupling suppression structure for suppressing mutual coupling according to an arrangement of antenna elements to increase antenna performance.

An array antenna refers to an antenna having a high directivity and a gain by arranging a plurality of antenna elements at a predetermined position and interval on a linear or planar surface and combining the respective beams of the antenna elements.

However, due to the mutual coupling between the plurality of antenna elements, the performance of the entire antenna is reduced,

In particular, since the radar composed of the array antenna is operated in a wide frequency band, due to mutual coupling between the antenna elements, a phenomenon in which the gain of the antenna is significantly lowered at a specific frequency may occur.

Therefore, the gain reduction of the antenna caused by the mutual coupling between the antenna elements adversely affects the detection range of the radar, thereby degrading the performance of the radar.

Accordingly, the present invention was devised to solve the above problems, and in an array antenna such as a radar operating a wide frequency band, mutual coupling suppression that prevents the gain from dropping in a specific frequency band due to mutual coupling between antenna elements. It is an object of the present invention to provide an array antenna having a structure.

According to the spirit of the present invention, in the antenna element, N * M matrix structure-N (row) is a positive integer of at least 2 or more (C _{1 ,} C _{2 ..} C _N ), and M (column) is positive of at least 3 or more. In the array antenna arranged at integers (R ₁ , R _{2 ,} R _{3 ...} R _M )-, the first antenna element -n arranged in a predetermined row of C _n , R _{2m -1} and emitting a signal is At least two positive integers maximizing N, m is a positive integer maximizing M / 2; A second antenna element disposed in a row C _n , R _{2m +1} , and emitting a signal; C _{n -1} rows and R _2m columns, each of which reflects a signal emitted from the first antenna element toward a second antenna element and reflects a signal emitted from the second antenna element toward a first antenna element. 3 antenna elements; In the case where n is an even or odd number, optionally, the column direction is spaced in any one of the separation space between the first antenna element and the third antenna element and the separation space between the second antenna element and the third antenna element. The array antenna may include an array antenna having a mutual coupling suppression structure including a blocking member for blocking a signal emitted from the second antenna element and reflected from the third antenna element toward the first antenna element.

In this case, the blocking member may be formed of a metal material having a width and a length so as to resonate corresponding to a frequency deviating from a frequency within an operating range of the array antenna.

The blocking member may be configured in the form of a rectangular thin film.

Meanwhile, a foam is formed between the C _n rows and the C _{n −1} rows to maintain the separation between the antenna elements, and the blocking member may be inserted into the foam.

The antenna element may have a dipole shape.

The array antenna having the mutual coupling suppression structure according to the present invention suppresses the mutual coupling effect between adjacent antenna elements at a diagonal position in the array antenna that must operate a wide bandwidth, so that the antenna gain is decreased at the corresponding frequency and the reflection coefficient is increased. There is an advantage to increase the performance of the array antenna by preventing it.

1 is a plan view showing the configuration of a conventional array antenna in which the antenna elements are arranged in an 8 * 8 matrix structure.
FIG. 2 is a graph illustrating a simulation result of a conventional array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm antenna gain variation due to mutual coupling.
3 is a graph illustrating a simulation result of a conventional array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm reflection coefficients due to mutual coupling.
4 is a plan view illustrating the configuration of an embodiment of an array antenna having a mutual coupling suppression structure according to the present invention.
FIG. 5 is a side view illustrating the configuration of the embodiment shown in FIG. 4. FIG.
FIG. 6 is a bottom view illustrating the structure of the embodiment shown in FIG. 4.
FIG. 7 is an enlarged view of an enlarged portion B of FIG. 4.
8 is provided with a blocking member in an array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm that the gain of the antenna is increased in a specific frequency band of the array antenna having the mutual coupling suppression structure according to the present invention. This is a graph showing the simulation results.
9 is provided with a blocking member in an array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm that the reflection coefficient is reduced in a specific frequency band of the array antenna having the mutual coupling suppression structure according to the present invention. It is a graph showing the simulation result.

Hereinafter, a preferred embodiment of an array antenna having a mutual coupling suppression structure according to the present invention will be described.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings.

However, the present invention is not limited by the embodiments disclosed below, but will be implemented in various different forms, only the embodiments are to make the disclosure of the present invention complete, and those of ordinary skill in the art to which the present invention belongs. It is provided to fully inform those skilled in the art of the scope of the invention, which is to be defined only by the scope of the claims.

In addition, in the description of the present invention, if it is determined that related related art and the like may obscure the gist of the present invention, detailed description thereof will be omitted.

Prior to describing the array antenna having the mutual coupling suppression structure according to the present invention, the mutual coupling between the antenna elements of the array antenna will be briefly described.

1 is a plan view showing the configuration of a conventional array antenna in which the antenna elements are arranged in an 8 * 8 matrix structure.

As shown in FIG. 1, the array antenna has a configuration in which a dipole-shaped antenna element A composed of a conductor is disposed at regular intervals up, down, left, and right, and the antenna element A is surrounded by a foam F2. Have

And between the rows and rows, a foam (F1) for maintaining the spacing is inserted.

As shown in FIG. 1, when simultaneous feeding of the antenna elements A of the array antenna is performed in the same phase, the antenna elements A1 and A3 are separated by a straight line d in the diagonal direction of the A1 and A3. Looking at the mutual coupling between the antenna elements in the antenna element A2,

The sum of the signals a1 and a4 in the antenna element A1 is represented by the following equation (1).

Where A denotes the magnitude of the signal, k ₀ denotes a value of 2π / λ, d denotes a linear distance between A1 and A2, and A2 and A3, and a1 and a3 in FIG. A3 and A4 in FIG. 1 indicate signals reflected from the antenna element A2 and incident on the antenna element A3 and A1, respectively.

That is, the sum S of the signals is the sum of the signal emitted from A1 and the signal emitted from A3, the phase delay and the phase reversal occur from A2, reflected and incident to A1.

At this time, the sum of the signals (a1, a4) in the antenna element A1 at a specific frequency of λ = 2d can be represented again as in Equation 2.

That is, it can be seen that the antenna elements A1 and A3 are destructive interference due to mutual coupling at a specific frequency at λ = 2d.

FIG. 2 is a graph illustrating a simulation result of a conventional array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm antenna gain variation due to mutual coupling. FIG. 3 is a reflection of mutual coupling. In order to confirm the coefficient, it is a graph showing the result of simulating a conventional array antenna in which the antenna elements are arranged in a 12 * 12 matrix structure.

On the other hand, as a result of constructing and testing an array antenna having a 12 * 12 matrix structure, as shown in FIG. 2, in the operating frequency band, near the frequency corresponding to the center frequency * 0.96 (indicated by the red dotted line in the drawing) There was a problem that the antenna gain is significantly lowered. In addition, as shown in Figure 3, it can be seen that the reflection coefficient increases near the frequency corresponding to the center frequency * 0.96 (indicated by the red dotted line in the drawing) within the operating frequency band. Here, IEEE gain of FIG. 2 represents a gain not including return loss, and Realized Gain represents a gain including return loss. 2 and 3 show the values obtained by dividing the frequency by the center frequency in the operating frequency band.

This problem is very fatal in an array antenna such as a radar that must operate a wide bandwidth, which can directly affect the detection range of the radar.

Therefore, the array antenna having the mutual coupling suppression structure according to the present invention is to suppress the mutual coupling between the antenna elements in the diagonal position as described above, to prevent the gain of the array antenna at a particular frequency is significantly reduced.

4 is a plan view illustrating the configuration of an embodiment of an array antenna having a mutual coupling suppression structure according to the present invention, and FIG. 5 is a side view illustrating the configuration of the embodiment shown in FIG. 6 is a bottom view illustrating the structure of the embodiment shown in FIG. 4.

4 shows only those parts which are characterized in order to conceptually clearly understand the constructional relationship for the preferred embodiment of the present invention, and as a result, various modifications of the drawings are expected, and the present invention will be greatly limited to the specific forms shown. There is no need.

Referring to FIG. 4, an embodiment 100 of an array antenna having a mutual coupling suppression structure according to the present invention is configured such that antenna elements are arranged in an 8 * 8 matrix structure, and the predetermined antennas radiate a signal among the arranged antenna elements. The first antenna element 110 and the second antenna element 120, and the third antenna element 130 that reflects the signal and the blocking member 140 for blocking the signal.

First, the first antenna element 110 and the second antenna element 120 will be described.

The first antenna element 110 selects any antenna element as a reference among antenna elements arranged in an 8 * 8 matrix structure, and may be disposed in a predetermined C _n row and R _{2m −1} column. here. n is a positive integer (2,3,4 ... 8) of at least 2 that maximizes 8, and m is a positive integer (1,2.3.4) that maximizes 4.

That is, C ₂ of FIG. To C ₈ rows, R ₁ R ₃ R ₅ R _{7 on the} column It may be any one of the antenna elements (A) arranged.

Antenna elements (A) are C ₁ of FIG. To eight columns (R ₁ with a predetermined spacing on each row of C ₈₎ . Eight antenna elements A are arranged to form R to R ₈ ). And, in order to support the strip-shaped antenna elements (A) having a dipole structure, as mentioned above, the antenna elements (A) has a structure surrounded by the foam (F1), C ₁ Forms F1 are inserted on the ground plate (G in FIGS. 5 and 6) located between each of the rows C- ₈ .

This, alternately among the antenna elements (A) R ₁ R ₃ R ₅ R _{7 on the} column If any one of the antenna elements (A) arranged arbitrarily selected and defined corresponds to the first antenna element 110, when the power is supplied to the first antenna element 110, it has directivity and emits a signal in a specific frequency band .

The second antenna element 120 is one of the antenna elements arranged in an 8 * 8 matrix structure, and is an antenna element coupled to the first antenna element 110 to cause destructive interference of a signal in a specific frequency band.

The second antenna element 120 is positioned on a predetermined C _n row in which the first antenna element 110 is located, and the second antenna element 120 is adjacent to each other by skipping one column to the R _{2m -1} column in which the first antenna element 110 is located. It is located at R _{2m + 1} . For example, as shown in FIG. 4, if the first antenna element 110 is defined as an antenna element positioned in row C _{5 and} row R ₄ , the second antenna element 120 may be an antenna positioned in row C _{5 and} row R _6. Is defined as an element. The second antenna element 120 is fed in the same phase as the first antenna element 110, has directivity, and emits a signal in a specific frequency band.

Next, the third antenna element 130 will be described.

The third antenna element 130 is one of the antenna elements arranged in an 8 * 8 matrix structure. The third antenna element 130 reflects a signal radiated to the first antenna element 110 and the second antenna element 120 to form a first antenna element 110. ) And an antenna element disposed at a position for transmitting a phase delay and a phase inverted signal to the second antenna element 120, respectively.

The third antenna element 130 is positioned on the C _{n - 1} row adjacent to the predetermined C _n row in which the first antenna element 110 and the second antenna element 120 are located, but the first antenna element 110 is located. and a position located on an adjacent R _2m R _2m-1 heat.

For example, as shown in FIG. 2, if the first antenna element 110 is defined as an antenna element positioned in row C _{5 and} row R ₄ , the third antenna element 130 may be an antenna positioned in row C _{4 and} row R _5. Is defined as an element. The third antenna element 130 has a signal emitted from the first antenna element 110 and the second antenna element 120 on the position thereof, respectively, in the second antenna element 120 and the first antenna element 110. Reflects off and causes mutual coupling.

FIG. 7 is an enlarged view of an enlarged portion B of FIG. 4.

As shown in FIG. 7, the distance between the first antenna element 110 and the third antenna element 130 is d as the center portion C1 of the first antenna element 110 and the center portion of the second antenna element 120. The distance d between the second antenna element 120 and the third antenna element 130 corresponds to a straight line connecting C2, and the central portion C2 and the third antenna element 130 of the second antenna element 120 are also included. Corresponds to the straight line connecting the center of the center (C3).

As described above, the mutual interference cancellation occurs at a specific frequency at which half the distance d and the wavelength are equal to each other, and thus the sum of the signals in the first antenna element 110 is zero.

In order to prevent this, the embodiment 100 includes a blocking member 130 to be described later.

Next, the blocking member 130 will be described.

The blocking member 130 serves to block a signal emitted from the second antenna element 120 and reflected from the third antenna element 130 toward the first antenna element 110.

As can be seen in Figures 4 to 6, the blocking member 130 has a thin film form in the long direction, it may be composed of a metal material. The size of the metal material constituting the blocking member 130 is formed so that the width and size are determined so as to resonate in the frequency band deviating from the frequency within the frequency operation range of the present embodiment (100).

This is to prevent the mutual coupling due to the blocking member 130 in advance by configuring the frequency band of the blocking member 130 and the operating frequency band of the present embodiment 100 made of a metal material differently.

In addition, the thickness of the blocking member 130 is preferably configured as thin as possible, so as not to affect the matching characteristics of the entire embodiment 100.

The blocking member 130 is located between the spaced apart space of the first antenna element 110 and the third antenna element 130, that is, the C _n row and the C _{n -1} row, which are diagonally positioned, and R _{2m −} It may be arranged in the column direction between column ₁ and row R _2m (hereinafter referred to as position 1).

Alternatively, a space between the second antenna element 120 and the third antenna element 130, which are diagonally positioned, that is, between the C _n rows and the C _{n −1} rows, may be located between the R _2m columns and the R _{2m +1} columns. It may be arranged in the column direction (hereinafter referred to as position 2).

This embodiment 100 is an even row (C _{2 ,} C _{4 ...} ) where the first antenna element 110 is located. According to the odd rows C _{1 ,} C _{3 ...} , The blocking member 130 may be alternately installed at the first and second positions. That is, as shown in Figure 4, when the first antenna element 110 is defined as an antenna element located in the column R ₅ on the even row C ₄ row, the blocking member 130 and the C ₃ row, the first position; When the first antenna element 110 is defined as an antenna element positioned at R ₅ on the C ₅ row, which is disposed in the column direction between rows C ₄ and R ₅ and R ₆ , the blocking member 130 may be Blocking member 130 and C ₅ row and C disposed in column direction between rows C ₅ and C _6, row ₆ and row R ₇ , which are positioned in the second position, and arranged between row C _{3 and} row C ₄ The blocking members 130 arranged between the _six rows are staggered.

This is to minimize the number of blocking members 130 disposed in the present embodiment 100, and to suppress the mutual coupling effect as much as possible.

As shown in FIGS. 4 to 6, the blocking member 130 is inserted into the foam F2 to maintain the separation between the antenna elements provided between the C _n rows and the C _{n −1} rows. A gap into which the blocking member 130 is inserted is formed in the foam F2, and the blocking member 130 is inserted into the gap.

Next, referring to Figures 8 and 9, when arranging the blocking member according to a preferred embodiment of the present invention, by suppressing mutual coupling between the antenna elements, the antenna gain vapor and reflection coefficient in a specific frequency band is reduced Let's check the effect.

8 is provided with a blocking member in an array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm that the gain of the antenna is increased in a specific frequency band of the array antenna having the mutual coupling suppression structure according to the present invention. This is a graph showing the simulation results.

9 is provided with a blocking member in an array antenna in which antenna elements are arranged in a 12 * 12 matrix structure in order to confirm that the reflection coefficient is reduced in a specific frequency band of the array antenna having the mutual coupling suppression structure according to the present invention. It is a graph showing the simulation result.

As can be seen in Figure 8, the antenna element is a 12 * 12 matrix structure as a result of the simulation by installing the blocking member of the copper material according to the present invention arranged in an array antenna, the center frequency within the operating frequency band shown in FIG. It can be seen that the gain decreased significantly near the frequency corresponding to * .96 (indicated by the red dotted line in the figure).

The IEEE gain of FIG. 8 represents a gain that does not include a return loss, and the realized gain represents a gain that includes a return loss. 8 and 9 show values obtained by dividing the frequency by the center frequency in the operating frequency band.

In addition, as can be seen in Figure 9, it can be seen that within the operating frequency band shown in Figure 3 the reflection coefficient increased significantly near the frequency corresponding to the center frequency * 0.96 (indicated by the red dotted line in the drawing) is reduced. have.

This result suggests that in the array antenna including the blocking member according to the preferred embodiment of the present invention, the mutual interference between antenna elements can be suppressed to cancel the destructive interference effect at a specific frequency.

In the above, a preferred embodiment of an array antenna having a mutual coupling suppression structure according to the present invention has been described.

It is to be understood that the above-described embodiments are illustrative in all aspects and should not be construed as limiting, the scope of the invention being indicated by the appended claims rather than the foregoing description, It is intended that all changes and modifications derived from the equivalent concept be included within the scope of the present invention.

110: first antenna element 120: second antenna element
130: third antenna element 140: blocking member
F1, F2: Foam G: Ground Plate

Claims (5)

The antenna element has an N * M matrix structure-N (rows) is a positive integer of at least 2 (C _{1 ,} C _{2 ...} C _N ), and M (columns) is a positive integer of at least 3 (R ₁ , R) _{2 ,} R _{3 ...} R _M )-array antennas,
The first antenna element-n, which is arranged in a predetermined row of C _n , R _{2m −1} , and emits a signal, is a positive integer of at least two or more that maximizes N, and m is a positive value that maximizes M / 2. essence-;
A second antenna element disposed in a row C _n , R _{2m +1} , and emitting a signal;
C _{n -1} rows and R _2m columns, each of which reflects a signal emitted from the first antenna element toward a second antenna element and reflects a signal emitted from the second antenna element toward a first antenna element. 3 antenna elements;
In the case where n is an even or odd number, optionally, the column direction is spaced in any one of the separation space between the first antenna element and the third antenna element and the separation space between the second antenna element and the third antenna element. An array coupling suppression structure including a blocking member arranged to be disposed in the second antenna element to block a signal emitted from the second antenna element and reflected from the third antenna element toward the first antenna element.
The method of claim 1,
The blocking member,
An array antenna having a mutual coupling suppression structure, characterized in that composed of a metal material having a width and a length so as to resonate with a frequency deviating from a frequency within an operating range of the array antenna.
The method of claim 1,
The blocking member,
An array antenna having a mutual coupling suppression structure, characterized in that formed in a rectangular thin film form.
The method of claim 1,
An array antenna having a mutual coupling suppression structure, wherein a foam is formed between the C _n rows and the C _{n −1} rows to maintain the separation between antenna elements, and the blocking member is inserted into the foam.
The method of claim 1,
The antenna element is an array antenna having a mutual coupling suppression structure, characterized in that the dipole form.

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