KR102192761B1 - Method and apparatus for detecting target - Google Patents

Abstract

A target detection method and apparatus are disclosed. The method of determining whether the radar is foreign matter is based on the step of receiving information on the beam pattern generated by the radar, the step of normalizing the beam pattern, and the difference in the size of the main lobe and the side rod of the normalized beam pattern. It may include the step of determining whether there is a foreign material.

Description

A method and apparatus for detecting a target TECHNICAL FIELD

The present invention relates to a target detection method, and more particularly, to a target detection method and apparatus using a radar.

A tracking radar is a device that tracks a target's position (distance, angle, speed, etc.) by placing a very narrow pulse from an antenna on the target and receiving a signal returning from the target. In general, a tracking radar uses a relatively sharp beamwidth to obtain more accurate target location information than a search radar. Due to this limitation of the beam width, it is not easy for a tracking radar to detect and track a specific target in 3D space. So the tracking radar needs to know the approximate location of the target available from search radar or other sources in order to track a particular target. Using this information, it is easy for the tracking radar to perform a target acquisition process in which the beam angle and distance of the antenna are matched to the location of a specific target. After acquiring such a target, the tracking radar can continuously track the target over time using the information on the direction of the antenna beam and the distance.

First, target acquisition can be said to be the first step in detecting a target signal received by mixing with a noise signal generated by various causes. Noise signals generally considered here include background echo, atmospheric noise, and noise generated by the radar's own receiver. Background noise and atmospheric noise are received by mixing with the target signal before the target signal returns to the receiver of the tracking radar, and the received target signal is additionally accompanied by noise as it goes through each step in the radar's own receiver. Therefore, in the target acquisition step of detecting the target signal, the characteristics of the noise signal must be carefully considered. In addition, the characteristics of the target signal itself are also a very important parameter in calculating the detection performance of the tracking radar. These parameters may be changed according to the state of the transmitter and receiver of the radar.

A first object of the present invention is to provide a method and apparatus capable of quickly determining whether or not a foreign substance is present in a radar used to detect a target.

A second object of the present invention is to provide a method and apparatus capable of accurately tracking a target of a radar since it is possible to quickly determine whether or not a foreign object is present on a radar.

In order to achieve the first object of the present invention, a method for determining whether a radar is foreign matter according to an aspect of the present invention includes receiving information on a beam pattern generated by the radar, normalizing the beam pattern, and It may include the step of determining whether a foreign matter of the radar is present based on information about a difference between the size of the main lobe and the size of the side rod of the normalized beam pattern. The normalizing of the beam pattern may be a step of normalizing by setting the maximum peak level of the beam pattern to 1. The step of determining whether foreign matter of the radar exists based on the information on the difference in the size of the main lobe and the size of the side rod of the normalized beam pattern is a difference between the maximum size of the main lobe and the maximum size of the side lobe. May be a step of comparing with a threshold value, and in this case, the threshold value may be set to 70% of the maximum size of the main lobe. In addition, the method of determining whether the radar is foreign matter may further include generating and transmitting a radar abnormal signal when it is determined that the foreign matter of the radar is present. The method for determining whether a foreign matter of the radar is present is the step of resetting and generating a beam pattern in consideration of the beam pattern of the radar in which the foreign matter exists, and a target based on the reset beam pattern. It may further include detecting.

In the radar foreign matter determination apparatus according to an aspect of the present invention for achieving the second object of the present invention described above, the radar foreign matter determination apparatus includes a processor, and the processor receives information on the beam pattern generated by the radar. It may be implemented to receive, normalize the beam pattern, and determine whether there is a foreign matter of the radar based on information about a difference between the size of the main lobe and the size of the side rod of the normalized beam pattern. The processor may be implemented to normalize by setting the maximum peak level of the beam pattern to 1. The processor is configured to determine whether a foreign matter of the radar is present based on information on a difference between the size of the main lobe and the side lobe of the normalized beam pattern, the maximum size of the main lobe and the maximum size of the side lobe. The difference between the sizes may be compared with a threshold value, and the threshold value may be set to 70% of the maximum size of the main lobe. The processor may be implemented to generate and transmit a radar abnormal signal when it is determined that the foreign matter of the radar is present. When it is determined that the foreign matter of the radar is present, the processor may be implemented to generate a beam pattern by resetting the beam pattern in consideration of the beam pattern of the radar in which the foreign matter exists, and to detect a target based on the reset beam pattern. have.

As described above, by using the target detection method and apparatus according to an embodiment of the present invention, it is possible to quickly determine whether or not a foreign substance is present in a radar used to detect a target. Thus, the radar can accurately track the target.

1 is a conceptual diagram showing a method of detecting a target of a radar according to an embodiment of the present invention.
2 is a flowchart illustrating an operation of determining whether a foreign object is embedded in a radar according to an exemplary embodiment of the present invention.
3 is a conceptual diagram showing a normalization process of a beam pattern according to an embodiment of the present invention.
4 is a flowchart illustrating a method of determining whether a radar is foreign matter in a radar system including a plurality of radars according to an exemplary embodiment of the present invention.
5 is a conceptual diagram showing an apparatus for determining whether a foreign object exists in a radar according to an embodiment of the present invention.
6 is a conceptual diagram showing a beam pattern and an object detection method of a radar according to an embodiment of the present invention.

In the present invention, various modifications may be made and various embodiments may be provided, and specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to a specific embodiment, it is to be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals have been used for similar elements.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In the present application, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. Hereinafter, the same reference numerals are used for the same elements in the drawings, and duplicate descriptions for the same elements are omitted.

Hereinafter, in an embodiment of the present invention, a method of detecting a target by a radar will be disclosed when a foreign object is caught in a part for detecting an object such as the front part of the radar. Hereinafter, in the embodiment of the present invention, a radar is described, but the present invention can be applied to an antenna other than a radar, and such an embodiment is also included in the scope of the present invention.

1 is a conceptual diagram showing a method of detecting a target of a radar according to an embodiment of the present invention.

Radar (radio detection and ranging) can be widely used commercially and for military use. It can also be used for air traffic control, for mapping ground contours, and for controlling vehicle traffic. The radar's system can transmit electromagnetic or radio waves. The reflected radio wave can be detected by a radar system receiver. The frequency of the radio wave used depends on the radar application. The size of the antenna required for radar can be proportional to wavelength and inversely proportional to frequency. In addition, the ability of a radar to focus energy transmitted and received in a small area may depend on both the size of the antenna and the frequency selection.

In FIG. 1, the radar discloses a method of detecting a target based on a level between a main lobe and a side-lobe among a beam pattern of a radar. The main lobe is a radiation lobe that includes the maximum radiation direction, and is generated because the radiation pattern has the strongest power and the radiation from each part of the antenna reaches the wide field in almost in phase. The radiation pattern generally has a set of lobes smaller than the main lobe, one of which is the side lobe. Side lobes are lobes near the main lobe. The measure of how well the power is concentrated in the main lobe can be expressed as a side lobe level, which can be determined based on the ratio of the maximum value of the main lobe and the maximum value of the side lobe.

Referring to the upper part of FIG. 1, a radar beam pattern is disclosed when the radar is stained with foreign substances and when the radar is not stained with foreign substances. In the case of the upper left of FIG. 1, the difference between the main lobe and the side lobe when the radar does not contain foreign substances, and the upper right of FIG. .

If the radar is stained with foreign substances, the difference in the relative size between the main lobe and the side lobe is reduced compared to the case where the radar is not stained with foreign substances, and in this case, it may be difficult for the radar to accurately detect the target object. In an embodiment of the present invention, it is possible to implement a radar system so that a detector can know when a foreign substance of the radar occurs by determining whether a foreign substance is embedded in the radar.

2 is a flowchart illustrating an operation of determining whether a foreign object is embedded in a radar according to an exemplary embodiment of the present invention.

Referring to FIG. 2, a radar beam pattern may be generated to determine whether a foreign object is embedded in the radar (step S200).

The step of generating the radar beam pattern may perform a pre-processing step, a post processing step, and a beam pattern generating step.

In order to generate a radar beam pattern, a fast Fourier transform can be used. The FFT technology is implemented by optimizing the discrete Fourier transform. The FFT may require less computation than DFT. DFT is to change the input sequence of sampled data, and the frequency content or spectral representation of the sampled data sequence can be created.

In addition, beamforming may be performed to generate a radar beam pattern. Beamforming is a technology that focuses a radar transmitter and a receiver in a specific direction. The left and right directions can be called azimuth and the up and down directions are called altitude. Beamforming can be used to focus the radar at both azimuth and altitude.

The generated beam pattern is normalized (step S220).

The generated beam pattern may be set to a maximum peak level of 1 through a normalization process. In an embodiment of the present invention, information about a difference between the size of the main lobe and the size of the side lobe of the beam pattern may be obtained after normalizing the beam pattern.

Information on the difference between the size of the main lobe and the size of the side lobe of the beam pattern is acquired (step S240).

In the beam pattern, information about the size of the main lobe and the side lobe can be obtained. According to an embodiment of the present invention, whether or not a blockage occurs in the radar by performing a method of performing normalization to set the maximum peak level to 1 and obtaining information about the size of the main lobe and the side lobe in the beam pattern. You can judge about

It is determined whether or not foreign matter is present on the radar (step S260).

In an embodiment of the present invention, when a value calculated using an equation such as Equation 1 below is less than or equal to a certain threshold, it may be determined that a foreign matter exists in the radar.

<Equation 1>

If the value of the main lobe and the side lobe obtained from the beam pattern satisfies Equation 1, it is possible to detect the presence of foreign matter in the current radar, and in this case, a signal in which the foreign matter generated in the radar is I can. For example, the threshold value is set to 70, and it is possible to determine whether or not a foreign object exists on the radar.

When a foreign matter occurs in the radar through the method of determining a foreign matter as shown in FIG. 2, the foreign matter of the radar may be removed, thereby improving the target detection performance of the radar.

3 is a conceptual diagram showing a normalization process of a beam pattern according to an embodiment of the present invention.

3, a beam pattern is acquired (S300). The beam pattern may include a main lobe and a side lobe. The maximum peak level of the beam pattern is normalized (S320). According to an exemplary embodiment of the present invention, it is possible to determine whether or not foreign matters exist in the radar by performing a normalization process of setting the maximum peak level of the beam pattern to 1.

After normalization is performed based on the maximum peak level of the beam pattern, a difference value between the main lobe and the side lobe is calculated (S340).

4 is a flowchart illustrating a method of determining whether a radar is foreign matter in a radar system including a plurality of radars according to an embodiment of the present invention.

Referring to FIG. 4, the radar system determines a beam pattern generated from the radar (step S400).

A radar system may include a plurality of radars, and information on a radar beam pattern may be obtained by receiving information on a beam pattern generated from each radar. An identifier may be assigned to each beam pattern information, and it is possible to determine whether a beam pattern obtained from a radar is based on the assigned identifier.

Based on the beam pattern information, it is determined whether the radar is foreign matter (step S410).

As described above, it is possible to determine whether or not the radar is foreign material based on the beam pattern information. For example, it is possible to determine whether there is a foreign object in the current radar based on information about the difference between the size of the main lobe and the side lobe of the beam pattern. If the value calculated based on the difference between the main lobe and the side lobe is smaller than a set threshold (eg, 70), it may be determined that there is a foreign matter in the radar. Conversely, if the value calculated based on the difference between the main lobe and the side lobe is larger than the set threshold, it can be determined that there is no foreign matter in the radar.

When there is a foreign matter in the radar, information on the radar in which the foreign matter exists is transmitted (step S420).

When it is determined that a foreign material exists in a specific radar, information on the radar in which the foreign material exists can be transmitted to a system that monitors the radar so that an abnormality occurring in the radar can be identified.

5 is a conceptual diagram showing an apparatus for determining whether a foreign substance is present in a radar according to an embodiment of the present invention.

Referring to FIG. 5, the radar foreign matter determination apparatus may include a beam pattern information collection unit 500, a foreign matter determination unit 520, a communication unit 540, and a processor 560.

The beam pattern information collection unit 500 may be implemented to obtain information on a beam pattern generated by a radar. A radar system may include a plurality of radars, and information on a radar beam pattern may be obtained by receiving information on a beam pattern generated from each radar. An identifier may be assigned to each beam pattern information, and it is possible to determine whether a beam pattern obtained from a radar is based on the assigned identifier.

The foreign matter determination unit 520 may determine whether a foreign matter exists in the radar based on the beam pattern information collected from the beam pattern information collection unit 500. For example, it is possible to determine whether there is a foreign object in the current radar based on information about the difference between the size of the main lobe and the side lobe of the beam pattern. If the value calculated based on the difference between the main lobe and the side lobe is smaller than the set threshold value, it may be determined that there is a foreign matter in the radar. Conversely, when a value calculated based on the difference between the main lobe and the side lobe is greater than a set threshold (eg, 70), it may be determined that there is no foreign matter in the radar.

The communication unit 540 may be implemented to transmit information on whether a foreign matter exists in the radar determined by the foreign matter determination unit 520.

The processor 560 may be implemented to control the radar foreign matter determination unit 500, the foreign matter determination unit 520, and the communication unit 540.

6 is a conceptual diagram showing a beam pattern and an object detection method of a radar according to an embodiment of the present invention.

FIG. 6 discloses a method of detecting an object based on a corresponding beam pattern when the foreign matter of the radar cannot be immediately removed.

Referring to FIG. 6, the beamforming determiner acquires information on a beam pattern generated by a foreign material (step S600).

The beamforming determiner may newly set a beamforming pattern in consideration of the abnormally generated beam pattern information.

A beam pattern is generated based on the beam pattern determined by the beamforming determiner (step S610).

The beamforming determiner may determine a new beamforming pattern in consideration of a radar generating an abnormal pattern due to foreign matter. The beamforming determiner may determine a beamforming pattern in consideration of an abnormal beam pattern due to a foreign substance, and detect an object based thereon.

A target is detected based on the generated beam pattern (step S620).

The beamforming determiner may detect the target based on the newly determined beam pattern. The beamforming determiner may be implemented to detect a target based on a beam pattern abnormally generated by foreign substances.

Although described with reference to the above embodiments, those skilled in the art will understand that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention described in the following claims. I will be able to.

Claims (12)

In the method of determining whether the radar is foreign matter,
Receiving information on the beam pattern generated by the radar;
Normalizing the beam pattern; And
And determining whether a foreign matter of the radar is present based on information about a difference between a size of a main lobe and a size of a side lobe of the normalized beam pattern. The method of claim 1, wherein normalizing the beam pattern comprises:
A method of determining whether a radar has a foreign matter, which is a step of normalizing by setting the maximum peak level of the beam pattern to 1. The method of claim 2, wherein the determining whether foreign matter of the radar is present based on information about a difference between a size of a main lobe and a size of a side lobe of the normalized beam pattern comprises:
A method of determining whether a foreign matter in a radar is performed by comparing a difference between the maximum size of the main lobe and the maximum size of the side lobe with a threshold. The method of claim 3,
The threshold value is set to 70% of the maximum size of the main lobe. The method of claim 4,
When it is determined that the foreign matter of the radar is present, the method of determining whether the foreign matter of the radar further comprises generating and transmitting a radar abnormal signal. The method of claim 5,
If it is determined that the foreign material of the radar is present, determining a beam pattern of the radar in which the foreign material exists as a new beam pattern; And
The method of determining whether the radar is foreign matter, further comprising detecting a target based on the new beam pattern. In the radar foreign matter determination device, the radar foreign matter determination device comprises a processor,
The processor receives information on the beam pattern generated by the radar, normalizes the beam pattern, and provides information on the difference between the size of the main lobe and the side lobe of the normalized beam pattern. Radar foreign matter determination device implemented to determine whether there is. The method of claim 7, wherein the processor,
Radar foreign matter determination device implemented to normalize by setting the maximum peak level of the beam pattern to 1. The method of claim 8, wherein the processor,
The difference between the maximum size of the main lobe and the maximum size of the side lobe in order to determine whether there is a foreign matter of the radar based on information about the difference between the size of the main lobe and the size of the side lobe of the normalized beam pattern. Radar foreign matter determination device implemented to compare the threshold value. The method of claim 9,
Radar foreign matter determination device in which the threshold value is set to 70% of the maximum size of the main lobe. The method of claim 10, wherein the processor,
When it is determined that the foreign matter of the radar is present, the radar foreign matter determination device is implemented to generate and transmit a radar abnormal signal. The method of claim 11, wherein the processor,
When it is determined that the foreign matter of the radar is present, the beam pattern of the radar in which the foreign matter exists is determined as a new beam pattern,
Radar foreign matter determination device implemented to detect a target based on the new beam pattern.

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