KR102364866B1 - Active phase array radar system with sub-array structure and method for providing side lobe blocking function using the same - Google Patents

Abstract

Disclosed are an active phased array radar system having a sub-array structure and a method for providing a sub-lobe blocking function using the same. An active phased array radar system having a sub-array structure according to an embodiment of the present invention includes a main antenna in which a plurality of array elements are disposed, and an array element adjacent to each other by being positioned at the edge among a plurality of array elements constituting the main antenna. A first sub-lobe blocking antenna group including at least one sub-array element composed of A side-lobe blocking antenna group, a main beam pattern generated based on a signal received through the main antenna, a first side-lobe blocking beam pattern generated based on a signal received through the first side-lobe blocking antenna group, and a second side-lobe blocking antenna An active phased array radar system having a subarray structure, comprising: a receiver for generating a final beam pattern from which a signal received from a side lobe is removed by using a second side lobe blocking beam pattern generated based on a signal received through the group.

Description

ACTIVE PHASE ARRAY RADAR SYSTEM WITH SUB-ARRAY STRUCTURE AND METHOD FOR PROVIDING SIDE LOBE BLOCKING FUNCTION USING THE SAME

The present invention relates to an active phased array radar system having a sub-array structure and a method for providing a sub-lobe blocking function using the same.

A plurality of transmit-receive modules (TRMs) are disposed in the active phased array radar system, and hundreds to thousands of transmit/receive modules may be included. Since each transmission/reception module forms an independent individual transmission/reception channel, the active phased array radar system can electronically perform beam steering by adjusting the size and phase of each transmission/reception module.

On the other hand, in the radar reception signal environment, in addition to the target signal received after hitting the target, various interference signals such as jamming and clutter exist. When such interference signals are received at the side-lobe of the radar reception beam, the radar Target detection performance is reduced. In general, when a radar operates a reception beam, accurate target detection performance can be obtained by blocking a signal received in the side lobe direction except for a signal in the main-lobe direction of the reception beam. A side-lobe blanking (SLB) system using a separate antenna having a beam pattern that covers the side lobe of all areas except the main lobe of the beam pattern by the main antenna as a method to block the signal received in the side lobe direction. used

In an active phase array antenna in which a plurality of elements are arranged, a side lobe blocking antenna can be configured by using some array elements. However, when operating a radar by configuring a sub-array for efficient operation of radar resources when operating a reception beam, the beam pattern by the unit element of the sub-array structure includes all sub-lobes of the beam pattern by the main antenna according to the detailed configuration of the sub-array. may not be covered. In this case, if the interfering signal from some directions cannot be blocked, a problem may occur in the operation of the side lobe blocking system.

Hereinafter, the shortcomings of the general side lobe blocking system will be described with reference to FIGS. 1 to 4 .

1 is a block diagram of a general side-lobe blocking system, and FIG. 2 is a diagram illustrating beam patterns of the main antenna and the side-lobe blocking antenna in the case of FIG. 1 .

The radar side lobe blocking system is used to block unwanted signals from entering the side lobe of the main antenna beam in order to improve the radar target detection performance. In general, such a side-loop blocking system may further include a side-blocking antenna and a receiver, which are auxiliary antennas, in addition to the main antenna as shown in FIG. 1 . Accordingly, the side-lobe blocking system compares the signal magnitude of the main antenna channel with the signal magnitude of the side-lobe blocking antenna channel, and passes the signal only when the signal coming from the main antenna is large.

2, in order to obtain only the target signal, the beam pattern by the side lobe blocking antenna is designed to be larger than the size of the pattern level of the main antenna in all directions other than the main lobe direction of the beam pattern by the main antenna, so that all the side lobes are separated in space. should be able to cover it.

In an active phased array radar having a plurality of antenna elements, at least some of the antenna elements may be used as side-lobe blocking antennas. However, in the case of an active phased array radar having a sub-array structure, since the antenna elements are composed of at least one sub-array, it is difficult to form a beam pattern that can cover a wide area like a general side-lobe blocking antenna.

3 exemplarily illustrates the structure of an active phased array radar having a sub-array structure. Here, the unit of each sub-array may be 4x4. In the present specification, the 'sub-array antenna' refers to an antenna having at least one sub-array configured based on a predetermined unit of at least one array element.

4 is a diagram for explaining a difference between a beam pattern by a main antenna and a beam pattern by an arbitrary sub-array antenna.

Since each sub-array is configured as a unit of 4x4, the beam pattern by the sub-array antenna inevitably generates nulls in at least a part of the entire signal reception area. Referring to FIG. 4 , it can be confirmed that the signal level of the main antenna is greater than the sub-array signal level in at least a partial area except for the main lobe. Accordingly, when only the beam pattern of the sub-array antenna (refer to FIG. 3) is used, the entire beam pattern of the main antenna cannot be covered, so that the interference signal is not blocked in some areas.

SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned needs and/or problems.

In addition, the present invention provides an active phased array radar system having a sub-array structure that minimizes gain degradation by using a sub-array of external elements as a side-lobe blocking antenna in an active phased array radar to which a sub-array is applied, and a side-lobe blocking function using the same It aims to implement a method to do this.

Another object of the present invention is to implement an active phased array radar system having a sub-array structure capable of configuring a side-lobe blocking system without an additional side-lobe blocking antenna, and a method for providing a side-lobe blocking function using the same.

In addition, the present invention removes nulls generated in the sub-array structure by adjusting and synthesizing the phase values of sub-array elements used as side-lobe blocking antennas and forming a side-lobe blocking pattern that covers all side lobes of the beam pattern of the main antenna. An object of the present invention is to implement an active phased array radar system having a sub-array structure and a method for providing a side lobe blocking function using the same.

An active phased array radar system having a sub-array structure according to an embodiment of the present invention, an active phased array radar system having a sub-array structure and a method for providing a side lobe blocking function using the same are disclosed. An active phased array radar system having a sub-array structure according to an embodiment of the present invention includes a main antenna in which a plurality of array elements are disposed, and an array element adjacent to each other by being positioned at the edge among a plurality of array elements constituting the main antenna. A first sub-lobe blocking antenna group including at least one sub-array element composed of A side-lobe blocking antenna group, a main beam pattern generated based on a signal received through the main antenna, a first side-lobe blocking beam pattern generated based on a signal received through the first side-lobe blocking antenna group, and a second side-lobe blocking antenna and a receiver for generating a final beam pattern from which the signal received from the side lobe is removed by using the second side lobe blocking beam pattern generated based on the signal received through the group.

A method for providing a side lobe blocking function according to another embodiment of the present invention includes: a main antenna in which a plurality of array elements are disposed; a first side-lobe blocking antenna group positioned at an edge among a plurality of array elements constituting the main antenna and including at least one sub-array element composed of array elements adjacent to each other; a second side-lobe blocking antenna group located at the center of the main antenna among the plurality of array elements and including at least one sub-array element composed of adjacent array elements; A main beam pattern generated based on a signal received through the main antenna, a first side-loop blocking beam pattern generated based on a signal received through the first side-loop blocking antenna group, and a second side-lobe blocking antenna group received through a receiver for generating a final beam pattern from which the signal received from the side lobe is removed by using the second side lobe blocking beam pattern generated based on the signal; A method for providing a side lobe blocking function of an active phased array radar system having a sub-array structure, comprising: a main antenna generating a main beam pattern; generating, by the first side-loop blocking antenna group, a first side-loop blocking beam pattern; generating, by the second side-blocking antenna group, a second side-blocking beam pattern; and generating, by the receiver, a final beam pattern from which side lobes are removed by using the first and second side lobe blocking beam patterns in the main beam pattern.

The effects of an active phased array radar system having a sub-array structure and a method for providing a sub-lobe blocking function using the same according to an embodiment of the present invention will be described as follows.

In the present invention, the gain degradation can be minimized by using the sub-array of the outer element as the side-lobe blocking antenna in the active phased-array radar to which the sub-array is applied.

In addition, the present invention can configure a side-loop blocking system without an additional side-lobe blocking antenna.

In addition, according to the present invention, by adjusting and synthesizing the phase values of sub-array elements used as side-lobe blocking antennas, nulls generated in the sub-array structure are removed and a side-lobe blocking pattern covering all side lobes of the beam pattern of the main antenna can be formed. .

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following description. .

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included as a part of the detailed description for better understanding of the present invention, provide embodiments of the present invention, and together with the detailed description, explain the technical features of the present invention.
1 is a block diagram of a general side lobe blocking system.
FIG. 2 is a diagram illustrating beam patterns of a main antenna and a side lobe blocking antenna in the case of FIG. 1 .
3 exemplarily illustrates the structure of an active phased array radar having a sub-array structure.
4 is a diagram for explaining a difference between a beam pattern by a main antenna and a beam pattern by an arbitrary sub-array antenna.
5 is a diagram illustrating an active phased array radar system having a sub-array structure according to an embodiment of the present invention.
6 is a view for explaining the detailed configuration of an active phased array radar system having a sub-array structure according to an embodiment of the present invention.
7 (a) is a diagram for illustrating the phase of the first side-lobe blocking antenna group.
FIG. 7(b) is a view showing a beam pattern of sub-array element No. 4 of FIG. 7(a).
8 is a diagram for illustrating a first side-lobe blocking beam pattern.
9 and 10 are diagrams for explaining an implementation example according to an embodiment of the present invention.
11 is a flowchart of a method for providing a side lobe blocking function according to an embodiment of the present invention.

Hereinafter, the embodiments disclosed in the present invention will be described in detail with reference to the accompanying drawings, but the same or similar components are assigned the same reference numerals regardless of reference numerals, and overlapping descriptions thereof will be omitted. The suffixes "module" and "part" for components used in the following description are given or mixed in consideration of only the ease of writing the specification, and do not have distinct meanings or roles by themselves. In addition, in describing the embodiments disclosed in the present invention, if it is determined that detailed descriptions of related known technologies may obscure the gist of the embodiments disclosed in the present invention, the detailed description thereof will be omitted. In addition, the accompanying drawings are only for easy understanding of the embodiments disclosed in the present invention, and the technical spirit disclosed in the present invention is not limited by the accompanying drawings, and all changes included in the spirit and scope of the present invention , should be understood to include equivalents or substitutes.

Terms including an ordinal number such as 1st, 2nd, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present application, terms such as “comprises” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

5 is a diagram illustrating an active phased array radar system having a sub-array structure according to an embodiment of the present invention.

5, an active phased array radar system having a sub-array structure according to an embodiment of the present invention includes an active phased array radar 100 and a receiver 200 having a sub-lobe blocking function. can

In the active phased array radar 100 , a plurality of array elements may be regularly arranged in a triangular array form. The active phased array radar 100 may include a main antenna 110 configured with all of a plurality of array elements and a side-lobe blocking antenna configured with at least some array elements among a plurality of array elements constituting the main antenna. That is, some of the plurality of array elements can be used as a main antenna while being used as a side-lobe blocking antenna, so that they can be used repeatedly.

For example, the active phased array radar 100 may include one main antenna 110 and at least one side lobe blocking antenna. Here, the side-lobe blocking antenna is to remove a near side-lobe in an area close to the main beam and a far side-lobe in a far area. The sidelobe blocking pattern in the near area can be referred to as the near-side SLB pattern, and the sidelobe blocking pattern in the far area can be referred to as the far-side SLB pattern. The near-side SLB pattern is to remove the side lobe near the main lobe. The far-side SLB pattern is to block the side lobe where null occurs due to the unit subarray structure.

Specifically, the active phased array radar 100 may include a main antenna 110 , a first side-lobe blocking antenna group 123 , and a second side-lobe blocking antenna group 121 . The first and second side-loop blocking antenna groups may include at least one first and second side-loop blocking antenna, respectively. Here, the first side lobe blocking antennas 123-1 to 123-8 may be located at the edge of the main antenna, and the second side lobe blocking antenna may be located at the center. The first side-lobe blocking antenna group may be implemented by, for example, first to eighth sub-array elements 123-1 to 123-8. Here, the sub-array element refers to a unit composed of a plurality of array elements, and may also be referred to as a 'sub-array antenna' or a 'sub-lobe blocking antenna'. Meanwhile, the number of first side-lobe blocking antennas is not limited according to an example, and may be implemented with a different number of array elements depending on the case.

The receiver 200 receives a main beam pattern generated using a signal received from the main antenna and at least one side-lobe blocking beam pattern, preferably two side-lobe blocking beam patterns, generated using a signal received from the side-lobe blocking antenna. A final beam pattern in which the signal received from the side lobe is removed can be generated.

For example, the receiver 200 may generate a final beam pattern from which a signal received from the side lobe is removed by removing at least one side-lobe blocking beam pattern, preferably two beam patterns, from the main beam pattern.

6 is a view for explaining the detailed configuration of a planar array antenna according to an embodiment of the present invention. Here, Fig. 6(a) shows a sub-array structure to be applied to an embodiment of the present invention, and Fig. 6(b) shows a weight size distribution of the entire antenna.

Referring to FIG. 6A , the active phased array radar 100 according to an embodiment of the present invention may include one main antenna 110 and at least one side lobe blocking antenna 120 . The at least one side-loop blocking antenna may be classified into a first side-loop blocking antenna group 123 and a second side-loop blocking antenna group 121 .

The first side-lobe blocking antenna group 121 includes at least one sub-array element that is positioned at an edge among a plurality of array elements constituting the main antenna and is composed of array elements adjacent to each other. The first side-loop blocking antenna may be present in at least two areas of the main antenna.

In addition, according to an embodiment, the array elements constituting the first side-lobe blocking antenna may be disposed in an area having a low weight in the entire antenna so that the decrease in gain of the received signal is minimized (refer to FIG. 6(b) ). 6(b) shows the distribution of the weight size (taylor -35 dB) of the entire antenna. The first side-lobe blocking antennas located at the edge are included in the low weight region, so that the gain of the signal received through the main antenna is reduced to a minimum. It can be seen that

The second side-lobe blocking antenna group 121 includes at least one sub-array element positioned at the center of the main antenna among the plurality of array elements and composed of array elements adjacent to each other. The second side lobe blocking antenna may be present in at least one area of the main antenna. However, the second side-loop blocking antenna is located in an area adjacent to each other, unlike the first side-loop blocking antenna.

The first and second side-lobe blocking antennas may be composed of 16 array elements adjacent to each other. In addition, the sub-array element may be composed of 4 x 4 array elements as a unit.

In an embodiment, the first side-blocking beam pattern by the first side-blocking antenna group may be obtained by averaging the power of the beam patterns of the sub-array elements of the steered edge. In the case of the second side-loop blocking beam pattern, the second side-loop blocking antenna located at the center of the main antenna may be used without phase adjustment.

The array elements used in the second side-lobe blocking beam pattern may simultaneously perform the side-lobe blocking function while using a channel related to the reception signal of the main antenna.

The receiver subtracts both the first side-lobe blocking beam pattern and the second side-lobe blocking beam pattern from the main beam pattern to generate a final beam pattern from which side lobes are removed, preferably a final beam pattern image.

FIG. 7(a) is a view for illustrating the phase of the first sub-lobe blocking antenna group, and FIG. 7(b) is a view showing the beam pattern of the fourth sub-array element of FIG. 7(a).

Referring to FIG. 7A , the first side-lobe blocking antennas may exist in at least two areas of the main antenna. In this case, the first side lobe blocking antenna may be positioned to face each other in order to remove the side lobe signal, and the number of array elements constituting it may be any one of 4, 8, 12, or 16. Meanwhile, the array elements constituting the first side-lobe blocking antenna cannot be used as a reception channel of the main antenna.

In one embodiment, so that the first side-loop blocking beam pattern is realized, the sub-array element belonging to the first side-loop blocking antenna group has a null position in the opposite direction from its own position (refer to the beam pattern in Fig. 4(b)) The phase is adjusted to steer the center. FIG. 7( b ) shows, for example, a beam pattern by sub-array element No. 4 . Since the 4th sub-array element is positioned at about 10 o'clock, the sub-array element steers the null position in the 4 o'clock direction. The first sub-lobe cut-off beam pattern is obtained by averaging the power over the beam patterns of a plurality of sub-array elements (eg, eight sub-array elements) steered in the manner described above (see FIG. 8 ). In FIG. 8 , the left side shows the Near-side SLB pattern, and the right side shows the Far-side SLB pattern.

9 and 10 are diagrams for explaining an implementation example according to an embodiment of the present invention.

Fig. 9 shows the 2D side lobe blocking pattern, and Fig. 10 shows the azimuth/elevation pattern. In FIG. 10, "Chambon* solid line shows the beam pattern of the main antenna, the green solid line shows the second side-lobe blocking beam pattern, and the blue solid line shows the first side-lobe blocking beam pattern. It is possible to implement a side-lobe blocking system by creating a pattern that covers all areas except the main lobe of the main antenna beam pattern while using the sub-array structure and channel without installing the receiver and sub-array.

The side lobe blocking pattern generation method proposed by the present invention is not limited to a specific sub-array as shown in FIG. 3 . This method is applicable to other active phased array antennas having a multi-channel planar array structure using a plurality of unit sub-array elements. The use of the far-side SLB pattern outer element uses 8 unit sub-arrays in the example, but in some cases, it can be expanded to 4, 8, 12, 16, etc. under the condition that there is no significant loss in the gain of the receiving antenna.

11 is a flowchart of a method for providing a side lobe blocking function according to an embodiment of the present invention.

A detailed description of each step in the flowchart of FIG. 11 is common to that described above with reference to FIGS. 5 to 10 . The main antenna may generate a main beam pattern (S1101). The first side-loop blocking antenna group may generate a first side-loop blocking beam pattern (S1102). The second side-loop blocking antenna group may generate a second side-loop blocking beam pattern (S1103). The receiver may generate a final beam pattern from which side lobes are removed by using the first and second side lobe blocking beam patterns in the main beam pattern (S1104).

The present invention described above can be implemented as computer-readable codes on a medium in which a program is recorded. The computer-readable medium includes all types of recording devices in which data readable by a computer system is stored. Examples of computer-readable media include Hard Disk Drive (HDD), Solid State Disk (SSD), Silicon Disk Drive (SDD), ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc. There is also a carrier wave (eg, transmission over the Internet) that is implemented in the form of. Accordingly, the above detailed description should not be construed as restrictive in all respects but as exemplary. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (14)

a main antenna on which a plurality of array elements are disposed;
a first side-lobe blocking antenna group positioned at an edge among a plurality of array elements constituting the main antenna and including at least one sub-array element composed of array elements adjacent to each other;
a second side-lobe blocking antenna group located at the center of the main antenna among the plurality of array elements and including at least one sub-array element composed of adjacent array elements;
A main beam pattern generated based on a signal received through the main antenna, a first side-loop blocking beam pattern generated based on a signal received through the first side-loop blocking antenna group, and a second side-lobe blocking antenna group received through a receiver for generating a final beam pattern from which the signal received from the side lobe is removed by using the second side lobe blocking beam pattern generated based on the signal;
including,
Subarray structure, characterized in that the subarray elements associated with the first sideblock antenna group are phased to steer a null position in the opposite direction from their respective positions so that the first sideblock beam pattern is realized. An active phased array radar system with According to claim 1,
The subarray element is
An active phased array radar system having a sub-array structure, characterized in that it consists of 16 array elements adjacent to each other. 3. The method of claim 2,
An active phased array radar system having a sub-array structure, characterized in that the sub-array element is composed of 4 x 4 array elements as a unit. According to claim 1,
An active phased array radar system having a sub-array structure, characterized in that the sub-array elements of the first side-lobe blocking antenna group are positioned to face each other to cancel the side-lobe signal. According to claim 1,
An active phased array radar system having a sub-array structure, characterized in that the number of sub-array elements of the first side lobe blocking antenna group is any one of 4, 8, 12 or 16. delete According to claim 1,
The active phased array radar system having a sub-array structure, characterized in that the first sub-lobe cut-off beam pattern is obtained by taking the power average of the beam patterns of the sub-array elements of the steered edge. According to claim 1,
the receiver,
An active phased array radar system having a sub-array structure, characterized in that by subtracting both the first side-lobe blocking beam pattern and the second side-lobe blocking beam pattern from the main beam pattern, an image with the side lobe removed is generated. According to claim 1,
An active phased array radar system having a sub-array structure, characterized in that in the case of the second side-lobe blocking beam pattern, a sub-array located in the center of the main antenna is used without phase adjustment. According to claim 1,
An active phased array radar system having a sub-array structure, characterized in that the array elements used in the second side-lobe blocking beam pattern simultaneously perform a side-lobe blocking function while using a channel related to the received signal of the main antenna. According to claim 1,
An active phased array radar system having a sub-array structure, characterized in that the array elements belonging to the first side-lobe blocking antenna group cannot be used as a reception channel of the main antenna. According to claim 1,
An active phased array radar system having a sub-array structure, characterized in that the sub-array elements constituting the first side-lobe blocking antenna group are arranged in an area having a low weight in the entire antenna so that a decrease in the gain of the received signal is minimized. a main antenna on which a plurality of array elements are disposed; a first side-lobe blocking antenna group positioned at an edge among a plurality of array elements constituting the main antenna and including at least one sub-array element composed of array elements adjacent to each other; a second side-lobe blocking antenna group located at the center of the main antenna among the plurality of array elements and including at least one sub-array element composed of adjacent array elements; A main beam pattern generated based on a signal received through the main antenna, a first side-loop blocking beam pattern generated based on a signal received through the first side-loop blocking antenna group, and a second side-lobe blocking antenna group received through a receiver for generating a final beam pattern from which the signal received from the side lobe is removed by using the second side lobe blocking beam pattern generated based on the signal; In a method for providing a side lobe blocking function of an active phased array radar system having a sub-array structure, comprising:
generating, by the main antenna, a main beam pattern;
generating, by the first side-blocking antenna group, a first side-blocking beam pattern;
generating, by the second side-blocking antenna group, a second side-blocking beam pattern;
generating, by a receiver, a final beam pattern from which side lobes are removed by using the first and second side lobe blocking beam patterns in the main beam pattern;
including,
A side-blocking function, characterized in that the sub-array elements associated with the first side-blocking antenna group are phased to steer a null position in the opposite direction from their respective positions so that the first side-blocking beam pattern is realized. method to provide. A computer system readable recording medium in which a program for executing the method of claim 13 in a computer system is recorded.

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