KR102188034B1 - Sidelobe blanking system for phased array radar - Google Patents

Abstract

The present invention provides a side lobe blocking system which implements a side lobe blocking function without using a separate auxiliary antenna. The side lobe blocking system of a phased array radar includes a side lobe blocking unit which determines whether a received signal is introduced from the side lobe using a combined channel output signal and a difference channel output signal, and blocking the received signal when the received signal is introduced from the side lobe.

Description

Side lobe blocking system of phased array radar {SIDELOBE BLANKING SYSTEM FOR PHASED ARRAY RADAR}

Embodiments of the present invention relate to a side lobe blocking system of a phased array radar.

Phased array radar is a radar that electronically steers a beam using phase difference, and is a technology that detects and tracks targets in air-to-air, air-to-ground, and air-to-sea using electromagnetic waves. Since each of the phased array radar modules operates, it can overcome the limitations of conventional mechanical radars that operate only one antenna. A pilot of a fighter equipped with a phased array radar can identify multiple enemy fighters at once and respond to all situations on the battlefield in real time, including ground, sea, and air conditions.

In order to implement accurate target detection performance, it is necessary to remove signals coming from angles other than the detection area. Otherwise, the radar's target detection performance is degraded due to unwanted signals such as clutter or jamming signals generated by terrain or buildings other than the detection area during the operation, and it is impossible to quickly respond to the wartime situation.

To solve this problem, an auxiliary antenna having a gain higher than the sidelobe level of the main antenna is provided, and the received signal received from the auxiliary antenna is used to compare it with the received signal of the main antenna, and the signal is referred to as a signal coming from the sidelobe. If determined, a method of removing the output signal of the main antenna so that it cannot be used as an input signal for target detection is used. This method is called sidelobe blanking (SLB).

However, when an auxiliary antenna is used to block a signal coming from the side lobe, the design and test cost and the auxiliary antenna manufacturing cost are high as a design requirement of the auxiliary antenna. In addition, since the auxiliary antenna is present, mutual coupling between the auxiliary antenna and other array elements occurs. Such mutual interference has a problem in that it affects signal reception, which may cause an error in estimating target information.

Korean registered patent: KR 10-2052712 B1 (announcement date: 2019.12.05.) Korean registered patent: KR 10-1240415 B1 (announcement date: 2013.03.11.)

An object of the embodiments of the present invention is to provide a side-lobe blocking system that implements a side-lobe blocking function without using a separate auxiliary antenna, and to reduce cost and time in designing and manufacturing an auxiliary antenna, and to reduce mean time between failures (MTBF). It is to provide a side lobe blocking system of a phased array radar that can increase and reduce the system size.

However, these tasks are exemplary, and the scope of the embodiments of the present invention is not limited thereby.

As a technical means for achieving the above-described technical problem, according to one aspect of the present disclosure, an array antenna element that transmits a radio wave toward a target and receives a radio wave reflected from the target as a received signal, and a sum channel by processing the received signal. A channel forming unit that generates an output signal and a secondary channel output signal, a side leaf that determines whether the received signal flows from the side lobe using the sum channel output signal and the secondary channel output signal, and blocks the received signal when the received signal flows from the side lobe. A side lobe blocking system of a phased array radar including a blocking portion may be provided.

In addition, the side lobe blocking unit may calculate an imaginary part of a value obtained by dividing the difference channel output signal by the sum channel output signal, compare the absolute value of the imaginary part with a predetermined threshold value, and block the received signal when the absolute value is greater than the threshold value.

Also, as the threshold value is changed, the detection range of the phased array radar may be changed.

Also, as the threshold value decreases, the detection range of the phased array radar may decrease.

In addition, the array antenna element is divided into a first area and a second area, and the channel forming unit generates the sum of the received signal of the first area and the received signal of the second area as a sum channel output signal, and the received signal of the first area And a difference between the received signal in the second area may be generated as a secondary channel output signal.

According to another aspect, an array antenna element that transmits a radio wave toward a target and receives a radio wave reflected from the target as a received signal, a channel forming unit that processes the received signal to generate a sum channel output signal and a difference channel output signal, Comprising a target information extracting unit that determines whether the received signal flows from the main lobe using the sum-channel output signal and the sub-channel output signal, and extracts target information using the sum-channel output signal and the sub-channel output signal when the received signal is introduced from the main lobe A phased array radar system can be provided.

According to another aspect, the array antenna element transmits a radio wave toward a target and receives the radio wave reflected from the target as a received signal, processing the received signal to generate a sum channel output signal and a difference channel output signal And determining whether the received signal flows from the side lobe using the sum channel output signal and the difference channel output signal, and blocking the received signal when the received signal is introduced from the side lobe. I can.

In addition, blocking the received signal includes calculating the imaginary part of the value obtained by dividing the difference channel output signal by the sum channel output signal, comparing the absolute value of the imaginary part with a predetermined threshold, and blocking the received signal when the absolute value is greater than the threshold. I can.

Also, as the threshold value is changed, the detection range of the phased array radar may be changed.

Also, as the threshold value decreases, the detection range of the phased array radar may decrease.

In addition, the array antenna element is divided into a first zone and a second zone, the sum channel output signal is the sum of the received signal in the first zone and the received signal in the second zone, and the difference channel output signal is the received signal in the first zone And a difference between the received signal in the second area.

According to another aspect, in a control method of a phased array radar system including an array antenna element and a processor, in the processor, a radio wave is transmitted toward a target through the array antenna element, and the radio wave reflected from the target is used as a received signal. Receiving, in the processor, processing the received signal to generate a sum channel output signal and a difference channel output signal, and in the processor, using the sum channel output signal and the difference channel output signal, it is determined whether the received signal flows from the main lobe. And extracting target information using the sum channel output signal and the difference channel output signal when introduced from the main lobe.

Other aspects, features, and advantages other than those described above will become apparent from the following drawings, claims, and detailed description of the invention.

According to embodiments of the present invention, by performing a side lobe blocking function without using a separate auxiliary antenna, cost and time for designing and manufacturing an auxiliary antenna can be reduced, and mean time between failures (MTBF) can be increased. , It is possible to provide a side lobe blocking system of a phased array radar capable of miniaturizing a phased array antenna system.

In addition, as the cost and time required for the design and manufacture of auxiliary antennas are reduced, the economy and time resources required for the production of tactical phased array radars can be saved, and as the phased array radar system is downsized, it is more necessary to mount phased array radars on fighters. It can be easier.

Of course, the scope of the embodiments of the present invention is not limited by these effects.

의 값을 나타내는 그래프이다.
도 4는 부엽차단 알고리즘의 흐름을 설명하기 위한 흐름도이다.
도 5는 위상 배열 레이더의 부엽 차단 방법을 설명하기 위한 흐름도이다.The present invention can be easily understood by a combination of the following detailed description and accompanying drawings, and reference numerals denote structural elements.
1 is a block diagram showing a side lobe blocking system of a phased array radar according to an embodiment of the present invention.
2 is a block diagram illustrating a phased array radar system according to another embodiment of the present invention.
3 is for each incident angle

It is a graph showing the value of.
4 is a flow chart for explaining the flow of a side lobe blocking algorithm.
5 is a flowchart illustrating a method of blocking a side lobe of a phased array radar.

In the present invention, since various transformations can be applied and various embodiments can be provided, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. Effects and features of the present invention, and a method of achieving them will be apparent with reference to the embodiments described later in detail together with the drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various forms. That is, what can be easily inferred by experts in the relevant technical field from the detailed description and embodiments is interpreted as belonging to the scope of the rights.

On the other hand, in the present specification, when a component is "connected" with another component, this includes not only a "direct connection" but also a "connected with another component in the middle". In addition, terms such as include or have means that the features or elements described in the specification are present, and do not preclude the possibility of adding one or more other features or elements in advance.

Some embodiments of the present disclosure may be represented by functional block configurations and various processing steps. Some or all of these functional blocks may be implemented with various numbers of hardware and/or software components that perform specific functions. For example, the functional blocks of the present disclosure may be implemented by one or more microprocessors, or may be implemented by circuit configurations for a predetermined function. In addition, for example, the functional blocks of the present disclosure may be implemented in various programming or scripting languages. The functional blocks may be implemented as an algorithm executed on one or more processors. In addition, the present disclosure may employ conventional techniques for electronic environment setting, signal processing, and/or data processing. Terms such as “mechanism”, “element”, “means” and “composition” can be used widely, and are not limited to mechanical and physical configurations. In addition, terms such as "?? unit" and "?? module" described in the specification mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software. have.

In addition, the connecting lines or connecting members between the components illustrated in the drawings are merely illustrative of functional connections and/or physical or circuit connections. In an actual device, connections between components may be represented by various functional connections, physical connections, or circuit connections that can be replaced or added.

In the following embodiments, terms such as first and second are not used in a limiting meaning, but are used for the purpose of distinguishing one component from another component. In addition, the expression in the singular includes a plurality of expressions unless clearly different from the context.

In addition, when an embodiment can be implemented differently, a specific process order may be performed differently from the described order. For example, two processes described in succession may be performed substantially simultaneously, or may be performed in an order opposite to the described order.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, and when describing with reference to the drawings, the same or corresponding components are assigned the same reference numerals, and redundant descriptions thereof will be omitted. .

In an embodiment, the phased array radar refers to a radar that has directivity by individually controlling a phase of a radio wave transmitted and received by each module after arranging a plurality of radio wave transmission/reception modules attached thereto. Phased array radar includes a passive electronically scanned array (PESA) or an active electronically scanned array (AESA). The phased array radar system is a radar system in which a radar element arranged in a fixed antenna electronically changes the direction of a radar wave to search and track a target. Electronically, the radar's detection beam formation, radiation pattern, and direction are quickly set, allowing simultaneous detection and tracking of various targets and automatic target selection and identification. In addition, it has a variety of flexible functions that can quickly cope with sudden changes in surrounding situations.

In an embodiment, a lobe refers to a round protrusion or piece on a radiation pattern of an antenna. The main lobe refers to a lobe including a maximum direction in the antenna radiation pattern or frequency spectrum. The main lobe represents the maximum energy transmission in a desired direction when designing an antenna or the like. Side lobe refers to a component that occurs small in radiation patterns other than the main lobe.

In an embodiment, the processor serves to control overall functions for executing the phased array radar system. The processor may be implemented with a central processing unit (CPU), a graphics processing unit (GPU), an application processor (AP), etc. included in the phased array radar system, but is not limited thereto.

1 is a block diagram showing a side lobe blocking system of a phased array radar according to an embodiment of the present invention. Referring to FIG. 1, a side lobe blocking system of a phased array radar may include an array antenna element 110, a channel forming unit 120, and a side lobe blocking unit 130.

The array antenna element 110 may transmit radio waves toward a target to be detected and receive radio waves reflected from the target as a reception signal. For example, the array antenna element 110 may be a phased array antenna capable of fast beam steering.

Referring to FIG. 1, each square of the array antenna element 110 may mean an antenna element. Several array antenna elements 110 may be arranged linearly. The array antenna element 110 may be divided into a zone A and a zone B to form a sum channel (S) and a difference channel (D).

The channel forming part 120 may form a sum channel S and a difference channel D. The sum channel (S) and the difference channel (D) can be calculated using Equation 1.

In Equation 1, A may be a received signal received in area A of the array antenna element, and B may be a received signal received in area B.

The side lobe blocking unit 130 is output from the channel forming unit The sum channel (S) and the difference channel (D) are used to determine whether a received signal flows from the side lobe, and when the received signal is introduced from the side lobe, the received signal can be blocked. Determination using the sum channel (S) and the difference channel (D) will be described later in more detail in FIGS. 3 and 4.

2 is a block diagram illustrating a phased array radar system according to another embodiment of the present invention. Referring to FIG. 2, the phased array radar system according to an embodiment may include a target information extraction unit 240. The target information extracting unit 240 may determine whether the received signal is introduced from the main lobe, and if the received signal is introduced from the main lobe, it may extract target information using a sum channel and a difference channel.

The target information extraction unit 240 may input a sum channel and a difference channel. The target information extracting unit 240 may determine whether the received signal flows from the side lobe using the input sum channel and the difference channel. By merging the side lobe blocking unit and the target information extraction unit, the system can be simplified and the overall processing speed of the system can be increased.

The target information extracting unit 240 may extract target information of a target introduced from the main lobe. The target information may include reflection intensity, target position (incident angle, elevation angle, target distance), target size, target motion characteristic, and geometric shape of a reflective object.

For example, the angle of incidence of the target may be calculated using Equation 2.

는 입사각,

은 안테나 배열의 총 개수이고,

는 배열과 배열간의 간격이고,

는 신호의 파장(wavelength)이다.

은 A구역의 안테나 및 B구역의 안테나를 모두 합한 개수이다. 수학식 2에서 Im(·)은 복소수에서 허수부(imaginary part)만 취하는 연산자이며, S, D는 표적들의 합채널과 차채널의 값이며 복소수이다.In Equation 2

Is the angle of incidence,

Is the total number of antenna arrays,

Is the spacing between arrays and arrays,

Is the wavelength of the signal.

Is the total number of antennas in zone A and antennas in zone B. In Equation 2, Im(·) is an operator that takes only the imaginary part of a complex number, and S and D are values of the sum channel and the difference channel of the targets and are complex numbers.

According to an embodiment, the phased array radar system may further include a target detection unit 230. The target detection unit 230 may determine whether the received signal is a target by using the sum channel output from the channel forming unit 220. When the received signal is a target, the target detection unit 230 may output a sum channel.

According to an embodiment, the determination as to whether the target has been introduced from the side lobe may be calculated by Equation 3.

는 차단하고 싶은 부엽 입사각에 따라 변경 될 수 있다.

를 변경함에 따라서 위상배열 레이더의 차단하고 싶은 부엽 입사각이 변경될 수 있고, 이에 따라 위상배열 레이더의 탐지범위가 변경될 수 있다.In Equation 3, Im(·) is an operator that takes only the imaginary part of a complex number. S and D are values of the sum channel and the difference channel, and are complex numbers. Threshold

Can be changed depending on the angle of incidence of the side lobe you want to block.

As is changed, the incident angle of the side lobe to be blocked of the phased array radar may be changed, and accordingly, the detection range of the phased arrayed radar may be changed.

는 0.5 내지 1.5의 값 중 한 값으로 조정될 수 있다. 수학식 3에서

의 값을 0.5로 설정 했을 경우 주엽 입사각은 약 -1.0°에서 +1.0°로 설정되고,

의 값을 1.5로 했을 경우 주엽 입사각은 약 -2.2°에서 +2.2°로 설정된다. 즉, 임계값

를 조절 함에 따라서 주엽의 범위를 조절할 수 있다. 따라서, 임계값

의 값을 조정하여 주엽의 영역을 선택할 수 있고, 주엽에서 들어오는 신호만 남기고 나머지 부엽에서 유입되는 표적을 제거 할 수 있다.For example, the threshold

May be adjusted to one of 0.5 to 1.5. In Equation 3

When the value of is set to 0.5, the main lobe incidence angle is set from about -1.0° to +1.0°,

When the value of is 1.5, the main lobe incidence angle is set from about -2.2° to +2.2°. That is, the threshold

By adjusting the range of the main lobe can be adjusted. Therefore, the threshold

By adjusting the value of, it is possible to select the area of the main lobe, leaving only the signal coming from the main lobe and removing the target from the other side lobe.

의 값을 나타내는 그래프이고, 도 3의 (a)는 입사각 -80° 내지 80°의

의 값을 도시한다. 도 3의 (b)는 입사각 -3° 내지 3°의

값을 도시한다. 도 3의 (b)를 참조하면, 임계값

의 값이 1로 기설정 되어있는 경우, 주엽(mainlobe)의 범위는 약 -1.8° 내지 1.8°일 수 있다.

의 절대값이 1보다 작은 경우 표적의 입사각이 주엽 내에 위치하는 것을 알 수 있다. 따라서, 수학식 3을 만족하면 해당 표적은 주엽 안에 위치하는 표적으로 판단될 수 있다.3 is according to the angle of incidence

Is a graph showing the value of, and (a) of FIG. 3 is an incidence angle of -80° to 80°

Shows the value of 3(b) shows the incident angle of -3° to 3°

Show the value. 3(b), the threshold value

When the value of is preset to 1, the range of the mainlobe may be about -1.8° to 1.8°.

If the absolute value of is less than 1, it can be seen that the angle of incidence of the target is located within the main lobe. Accordingly, if Equation 3 is satisfied, the target may be determined as a target located in the main lobe.

의 값이 1보다 감소하는 경우에는 주엽의 범위는 도시되어있는 약 -1.8° 내지 1.8°보다 감소할 수 있다. 반대로 임계값

의 값이 1보다 증가하는 경우에는 주엽의 범위는 -1.8° 내지 1.8°보다 증가할 수 있다.Not shown, but for example threshold

When the value of is decreased by less than 1, the range of the main lobe may decrease from about -1.8° to 1.8° as shown. Reverse threshold

When the value of is increased more than 1, the range of the main lobe may increase from -1.8° to 1.8°.

4 is a flow chart for explaining the flow of a side lobe blocking algorithm. It may be determined whether Equation 3 is satisfied by the input signal of the sum channel S and the difference channel D of the target. When it is determined that the target is in the main lobe by satisfying Equation 3, target information may be extracted. Conversely, when Equation 3 is not satisfied, it is determined that the target is in the side lobe, and the target may be deleted.

5 is a flowchart illustrating a method of blocking a side lobe of a phased array radar. Since the method of blocking the side lobe of the phased array radar shown in FIG. 5 is related to the embodiments described in the drawings described above, the contents described in the previous drawings are the method of FIG. It can also be applied to

Referring to FIG. 5, in step 510, the phased array antenna system may transmit a radio wave toward a target to be detected and receive a radio wave reflected from the target as a reception signal. In step 520, the phased array antenna system may form a sum channel and a difference channel based on the received signal. In step 530, the phased array antenna system may detect a target using the sum channel signal. In this case, in the case of a target, a sum channel can be output. In step 540, the phased array antenna system may block a signal introduced from the side lobe based on the input sum channel and the difference channel. If the received signal flows from the main lobe, the sum channel and the difference channel can be output. In step 550, the phased array antenna system may extract target information in the main lobe using the sum channel and the difference channel.

In the present specification (especially in the claims), the use of the term "above" and a reference term similar thereto may correspond to both the singular and the plural. In addition, when a range is described, it includes individual values belonging to the above range (unless otherwise stated), it is the same as describing each individual value constituting the range in the detailed description. Finally, if there is no explicit order or contradictory description of the steps constituting the method, the steps may be performed in an appropriate order. It is not necessarily limited to the order of description of the steps. The use of all examples or illustrative terms (for example, etc.) is merely for describing the technical idea in detail, and the scope is not limited due to the examples or illustrative terms unless limited by the claims. In addition, those skilled in the art will recognize that various modifications, combinations, and changes may be configured according to design conditions and factors within the scope of the appended claims or their equivalents.

As described above, the present invention has been described with reference to an embodiment shown in the drawings, but this is only exemplary, and it will be understood that various modifications and variations of the embodiments are possible from those of ordinary skill in the art. Therefore, the true technical scope of the present invention should be determined by the technical spirit of the appended claims.

110: array antenna element
120: channel forming portion
130: side lobe blocking portion
230: target detection unit
240: target information extraction unit

Claims (12)

In the side lobe blocking system of a phased array radar,
An array antenna element that transmits a radio wave toward a target and receives the radio wave reflected from the target as a reception signal;
A channel forming unit processing the received signal to generate a sum channel output signal and a difference channel output signal; And
A side lobe blocker configured to determine whether the received signal flows from the side lobe using the sum channel output signal and the difference channel output signal, and block the received signal when the received signal is introduced from the side lobe,
The side lobe blocking portion,
Calculating an imaginary part of a value obtained by dividing the difference channel output signal by the sum channel output signal, comparing the absolute value of the imaginary part with a predetermined threshold value, and blocking the received signal when the absolute value is greater than the threshold value. Array radar side lobe blocking system. delete The method of claim 1,
The detection range of the phased array radar is changed as the threshold value is changed, the side lobe blocking system of the phased array radar. The method of claim 1,
As the threshold value decreases, the detection range of the phased array radar decreases. The method of claim 1,
The array antenna element is divided into a first zone and a second zone,
The channel forming unit generates the sum of the received signal in the first area and the received signal in the second area as the sum channel output signal, and the received signal in the first area and the received signal in the second area A side lobe blocking system of a phased array radar that generates the difference in the second channel output signal. delete An array antenna element transmitting a radio wave toward a target and receiving the radio wave reflected from the target as a received signal;
Processing the received signal to generate a sum channel output signal and a difference channel output signal; And
Determining whether the received signal flows from the side lobe using the sum channel output signal and the difference channel output signal, and blocking the received signal when the received signal flows from the side lobe,
Blocking the received signal comprises:
Calculating an imaginary part of a value obtained by dividing the difference channel output signal by the sum channel output signal, comparing the absolute value of the imaginary part with a predetermined threshold value, and blocking the received signal when the absolute value is greater than the threshold value. How to block the side lobe of the array radar. delete The method of claim 7,
A method of blocking a side lobe of a phased array radar in which the detection range of a phased array radar is changed as the threshold value is changed. The method of claim 7,
As the threshold value decreases, the detection range of the phased array radar decreases. The method of claim 7,
The array antenna element is divided into a first zone and a second zone,
The sum channel output signal is the sum of the received signal in the first zone and the received signal in the second zone,
The secondary channel output signal is a difference between the received signal in the first zone and the received signal in the second zone, the side lobe blocking method of a phased array radar. delete

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