KR20200095998A - Apparatus and method for analyzing coverage of sar image - Google Patents

Abstract

According to the present invention, a device for analyzing an area capable of forming a SAR image may comprise: a parameter setting unit setting a first parameter of a synthetic aperture radar (SAR) image for an area of interest to be acquired and setting a second parameter for calculation of an image formation area; an SNR calculation unit calculating a signal to ratio (SNR) for the area of interest by the set first parameter; a synthetic aperture time calculation unit calculating synthetic aperture time (SAT) for the area of interest by the set second parameter; and an area calculation unit calculating a distribution area of the SAR image by the set first and second parameters and the calculated SNR and SAT.

Description

SAR image formation possible area analysis device and method thereof {APPARATUS AND METHOD FOR ANALYZING COVERAGE OF SAR IMAGE}

The present invention relates to a technique for analyzing the formation possible region of a SAR (Synthetic Aperture Radar) image, and more particularly, a SAR capable of analyzing in real time the obtainable region for a SAR image of a target quality in an aircraft-mounted radar. It relates to an apparatus and method for analyzing an image formation possible region.

As is known, conventional aircraft-mounted radars simply acquire SAR images within a pre-designed image formation possible area according to the resolution of the SAR image selected/set by the operator.

However, the area where the SAR image can be formed is not fixed by the resolution of the image, but can be changed in real time by the speed and altitude information of the aircraft that changes in real time, and the maximum image that the operator aims (desired) is formed. The available region of the SAR image may be changed depending on time (Synthetic Aperture Time (SAT)) and image quality (signal to ratio (SNR)).

Therefore, in the case of obtaining the SAR image according to the conventional method, the SAR image is acquired in an area that is narrower than the area in which the SAR image can be obtained, thereby losing the image formation area or the area where the SAR image can be obtained. As the SAR image is acquired in the region, a problem may arise that the resolution or SNR of the acquired SAR image becomes lower than the quality targeted by the operator.

Korean Patent Registration No. 10-1839041 (Announcement date: 2018. 03. 15.)

An object of the present invention is to provide an apparatus and method for analyzing a region capable of forming an SAR image capable of analyzing an obtainable region for an SAR image having a target quality in an aircraft-mounted radar in real time.

The present invention provides a computer-readable recording medium storing a computer program that allows a processor to perform a method for analyzing a formable region of an SAR image capable of analyzing an obtainable region of an SAR image of a target quality in real time from an aircraft-mounted radar. I want to provide.

The problem to be solved by the present invention is not limited to the ones mentioned above, and another problem to be solved that is not mentioned can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the following descriptions. will be.

According to an aspect of the present invention, a parameter setting unit for setting a first parameter of a Synthetic Aperture Radar (SAR) image for a region of interest to be acquired, and a second parameter for calculating an image formation region, and the set An image quality calculator that calculates a signal to ratio (SNR) for the region of interest based on the first parameter, and a maximum image formation time (SAT) for the region of interest based on the set second parameter. SAR including a maximum image time calculation unit that calculates a synthetic aperture time), and an area calculation unit that calculates a distribution area of the SAR image based on the set first parameter and the second parameter, the calculated SNR, and the SAT. An apparatus for analyzing an image formation possible area may be provided.

The image quality calculation unit of the present invention,

Equation

P _t : maximum transmit power

G _t : antenna transmission gain

G _r : Antenna reception gain

λ: wavelength

δ ₀ : backscattering index

△x: required distance resolution

△y: Required orientation resolution

k: Boltzmann constant

The SNR can be calculated by.

The maximum video time calculation unit of the present invention,

Equation

λ: wavelength

R: distance

v: platform speed

△y: Required orientation resolution

θ: angle

The SAT can be calculated by.

The maximum video time calculation unit of the present invention,

Equation

x', y': coordinates of the region of interest

h: height of the vehicle

R can be calculated by

The maximum video time calculation unit of the present invention,

Equation

θ _sq : squint angle

θ _de : Depression angle

The θ can be calculated by.

The maximum video time calculation unit of the present invention,

Equation

Θ _sq can be calculated by.

The maximum video time calculation unit of the present invention,

Equation

The θ _de can be calculated by.

If the calculated SAT is smaller than a preset SAT_max and the calculated SNR is greater than a preset SNR_required, the area calculator of the present invention may determine the distribution area of the SAR image.

According to another aspect, the present invention sets a first parameter of a Synthetic Aperture Radar (SAR) image for a region of interest to be acquired, and a second parameter for calculating an image formation region, and the set Calculating an image quality (SNR) for the region of interest based on a 1 parameter; calculating a maximum image formation time (SAT) for the region of interest based on the set second parameter; and It is possible to provide a method for analyzing a formable region of an SAR image including calculating a distribution region of the SAR image based on the first parameter and the second parameter, the calculated SNR and the SAT.

The present invention may further include the step of displaying the calculated distribution area of the SAR image on a display panel.

In the calculating of the distribution area of the present invention, if the calculated SAT is smaller than a preset SAT_max and the calculated SNR is greater than a preset SNR_required, it may be calculated as a distribution area of the SAR image.

According to another aspect, the present invention is a computer-readable recording medium in which a computer program for causing a processor to perform a method for analyzing a formable area of an SAR image is stored, wherein the method for analyzing a formable area to be acquired Setting a first parameter of a Synthetic Aperture Radar (SAR) image, setting a second parameter for calculating an image forming region, and determining an image quality (SNR) for the region of interest based on the set first parameter Calculating the maximum image formation time (SAT) for the ROI based on the set second parameter, the set first parameter and the second parameter, and the calculated SNR and the SAT It is possible to provide a computer-readable recording medium including the step of calculating the distribution area of the SAR image based on the SAR image.

According to an embodiment of the present invention, by analyzing in real time a region that can be obtained for an SAR image of a target quality from an aircraft-mounted radar, the SAR image of a target quality is obtained for a wide area by maximizing the performance of the radar. can do.

1 is a block diagram of an apparatus for analyzing a formable region of an SAR image according to an embodiment of the present invention.
2 is a diagram showing examples of various types of parameters set according to a user interface.
3 is an exemplary diagram for explaining a principle of calculating a distance R and an angle θ to calculate a maximum image formation time according to an embodiment of the present invention.
4 is an exemplary diagram of a distribution area of an SAR image calculated and finally displayed (displayed) according to an embodiment of the present invention.
5 is a flowchart illustrating a main process of calculating a distribution area of an SAR image based on parameters, image quality (SNR), and maximum image formation time (SAT) according to an embodiment of the present invention.

Advantages and features of the present invention, and methods for achieving them will be clarified with reference to embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms, and only these embodiments make the disclosure of the present invention complete, and those skilled in the art to which the present invention pertains. It is provided to fully inform the scope of the invention to the person, and the scope of the invention is only defined by the claims.

In describing the embodiments of the present invention, detailed descriptions of known functions or configurations will be omitted except when actually necessary in describing the embodiments of the present invention. In addition, terms to be described later are terms defined in consideration of functions in an embodiment of the present invention, which may vary according to a user's or operator's intention or practice. Therefore, the definition should be made based on the contents throughout this specification.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of an apparatus for analyzing a formable region of an SAR image according to an embodiment of the present invention, wherein a parameter setting unit 102, an image quality calculation unit 104, a maximum image time calculation unit 106, and a region It may include a calculation unit 108 and the like. Here, the area calculation unit 108 may include an angle calculation unit 1082.

Referring to FIG. 1, the parameter setting unit 102 may provide a function of setting (inputting) a parameter of a synthetic aperture radar (SAR) image to be acquired according to a user interface.

) 및 요구되는 SNR(signal to ratio), SAT(synthetic aperture time) 및 해상도 정보 등을 포함할 수 있으며, 또한, 항공기의 속도, 고도 정보, 안테나 이득 및 손실 파라미터 등을 포함할 수 있다.Here, the parameters of the SAR image to be acquired are the x, y coordinates of the region of interest on the ground when the antenna is viewed as the origin (

) And required signal to ratio (SNR), synthetic aperture time (SAT), and resolution information, and the like, and may include speed, altitude information, antenna gain and loss parameters, and the like.

As an example, as shown in FIG. 2, the parameter setting unit 102 may input (set) various types of parameters according to a user interface.

Here, in the case of the region of interest and SAT, if the boundary of the region of interest is entered, the aircraft (radar) is calculated to the corresponding boundary region, and the SAT can be calculated not to exceed the maximum SAT value if the maximum SAT is entered. have.

In this case, a parameter of the SAR image related to the ROI to be acquired may be defined as, for example, a first parameter, and a parameter related to calculation of the image forming region may be defined as, for example, a second parameter.

Next, the image quality calculation unit 104 may provide a function of calculating an image quality (SNR) for the region of interest based on parameters (first parameter) set through the parameter setting unit 102. . For example, the image quality calculator 104 may calculate the SNR through Equation 1 below.

[Equation 1]

In Equation 1 above, P _t represents the maximum transmission power, G _t represents the antenna transmission gain, G _r represents the antenna reception gain, and λ represents the wavelength (the wavelength of the operating wave operated by the radar). , δ ₀ represents the backscattering index, Δx represents the required distance resolution, Δy represents the required orientation resolution, and k represents the Boltzmann constant.

In addition, the maximum image time calculation unit 106 calculates a maximum image formation time (SAT) for the region of interest based on parameters (second parameter) set through the parameter setting unit 102. Function can be provided. For example, the maximum video time calculation unit 106 may calculate the SAT through Equation 2 below.

[Equation 2]

In Equation 2 above, R represents the distance (the distance from the radar to the target region (the region aiming for image formation)), v represents the platform speed, Δy represents the required orientation resolution, and θ represents It represents the angle (the angle between the traveling direction of the aircraft and the target area).

3 is an exemplary diagram for explaining a principle of calculating a distance R and an angle θ to calculate a maximum image formation time according to an embodiment of the present invention.

Referring to FIG. 3, the distance R may be calculated as in Equation 3 below, and the angle θ may be calculated as in Equation 4 below.

[Equation 3]

In Equation 3 described above, x'and y'represent coordinates of the region of interest, and h represents the altitude of the aircraft (aircraft).

[Equation 4]

In Equation 4 above, θ _sq represents a squint angle, and θ _de represents a depression angle.

Next, the area calculation unit 108 includes parameters (first and second parameters) set through the parameter setting unit 102, the SNR calculated through the image quality calculation unit 104, and the maximum area time calculation unit 106 Based on the SAT calculated through ), a function such as calculating a distribution area (ie, an image formation possible area) of the SAR image may be provided.

) 및 고각 조향 한계각도(

)내의 영역을 추가적으로 구분 및 계산하는 등의 기능을 제공할 수 있다.To this end, the area calculation unit 108 may include an angle calculation unit 1082, and this angle calculation unit 1082 includes the received antenna azimuth steering limit angle (

) And elevation steering limit angle (

) It can provide functions such as additionally classifying and calculating the area within.

,

는 아래의 수학식 5 및 수학식 6에서와 같이 관심 영역(

)의 좌표 및 비행체(항공기)의 고도 정보 h를 이용하여 계산될 수 있다.In Equation 4 above,

,

Is the region of interest (

) Can be calculated using the coordinates and altitude information h of the aircraft (aircraft).

[Equation 5]

[Equation 6]

That is, according to an embodiment of the present invention, the regions (x, y) input through a series of processes are compared for each coordinate to calculate SAT and SNR, respectively, and the calculated SAT value is smaller than the preset SAT_max, and the calculation If the generated SNR value is larger than the preset SNR_required, it may be determined (calculated) as an image formation region (a distribution region of an SAR image).

4 is an exemplary view of a distribution area of an SAR image calculated according to an embodiment of the present invention and finally displayed (displayed) on a display panel (monitor).

), (

)는 앞서 계산된 영역 중에

,

보다 큰 값을 갖는 영역을 삭제(구분)하는 역할을 수행할 수 있다.4, (

), (

) Is among the previously calculated areas

,

It can play a role of deleting (segmenting) areas with a larger value.

5 is a flowchart illustrating a main process of calculating a distribution area of an SAR image based on parameters, image quality (SNR), and maximum image formation time (SAT) according to an embodiment of the present invention.

Referring to FIG. 5, the parameter setting unit 102 includes a parameter of an SAR image to be acquired according to a user interface, that is, a first parameter of an SAR image related to an ROI to be acquired and a second parameter related to calculation of an image formation area. A parameter is set (input) (step 502).

That is, the parameter setting unit 102 inputs (sets) various types of parameters according to a user interface, as shown in FIG. 2 as an example.

Then, the image quality calculation unit 104 calculates the image quality (SNR) for the region of interest based on the first parameter set through the parameter setting unit 102 (step 504).

Next, the maximum image time calculation unit 106 calculates the maximum image formation time (SAT) for the region of interest based on the second parameter set through the parameter setting unit 102 (step 506).

) 및 고각 조향 한계각도(

)내의 영역을 추가적으로 구분 및 계산하는 각도 계산부(1082)를 포함할 수 있다.Thereafter, in the area calculation unit 108, the first parameter and the second parameter set through the parameter setting unit 102, the SNR calculated through the image quality calculation unit 104, and the maximum area time calculation unit 106 A distribution area (ie, an image formation possible area) of the SAR image is calculated based on the SAT (step 508). To this end, the area calculation unit 108 receives the received antenna azimuth steering limit angle (

) And elevation steering limit angle (

) It may include an angle calculation unit 1082 that additionally divides and calculates the area within.

In addition, the area calculation unit 108 may display (display) the distribution area of the SAR image calculated according to the embodiment of the present invention on the display panel (monitor) (step 510).

That is, according to an embodiment of the present invention, the regions (x, y) input through a series of processes are compared for each coordinate to calculate SAT and SNR, respectively, and the calculated SAT value is smaller than the preset SAT_max, and the calculation If the generated SNR value is greater than the preset SNR_required, it is finally calculated (determined) as an image formation area (distribution area of SAR image) and displayed (displayed) on the display panel.

Meanwhile, combinations of each block of the attached block diagram and each step of the flowchart may be performed by computer program instructions. These computer program instructions may be mounted on a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, so that instructions executed through a processor of a computer or other programmable data processing equipment may be used in each block or flowchart of the block diagram. In each step, means are created to perform the functions described.

These computer program instructions can also be stored in a computer readable or computer readable memory or the like that can be directed to a computer or other programmable data processing equipment to implement a function in a particular way, so the computer readable or computer readable memory The instructions stored in it are also possible to produce an article of manufacture containing instructions means for performing the functions described in each step of each block or flowchart of the block diagram.

In addition, since computer program instructions may be mounted on a computer or other programmable data processing equipment, a series of operation steps are performed on the computer or other programmable data processing equipment to generate a process executed by the computer to generate a computer or other program. It is also possible for instructions to perform possible data processing equipment to provide steps for performing the functions described in each block of the block diagram and in each step of the flowchart.

Further, each block or each step may represent a module, segment, or portion of code that includes at least one executable instruction for executing the specified logical function(s). It should also be noted that in some alternative embodiments it is possible that the functions mentioned in blocks or steps occur out of order. For example, two blocks or steps shown in succession may in fact be executed substantially simultaneously, or it is also possible that the blocks or steps are sometimes performed in reverse order depending on the corresponding function.

The above description is merely illustrative of the technical idea of the present invention, and those of ordinary skill in the art to which the present invention pertains may have various substitutions, modifications, changes, etc. without departing from the essential characteristics of the present invention. You will easily see this possible. That is, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to describe the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments.

Therefore, the protection scope of the present invention should be interpreted by the claims that will be described later, and all technical ideas within an equivalent range should be interpreted as being included in the scope of the present invention.

102: parameter setting unit
104: image quality calculation unit
106: maximum video time calculation unit
108: area calculation unit
1082: angle calculation unit

Claims (12)

A parameter setting unit for setting a first parameter of a Synthetic Aperture Radar (SAR) image for a region of interest to be acquired and a second parameter for calculating an image forming region;
An image quality calculator that calculates an image quality (SNR) for the ROI based on the set first parameter;
A maximum image time calculation unit that calculates a maximum image formation time (SAT) for the region of interest based on the set second parameter,
An area calculator that calculates a distribution area of the SAR image based on the set first parameter and the second parameter, the calculated SNR and the SAT
Apparatus for analyzing a formable area of a SAR image comprising a. The method of claim 1,
The image quality calculation unit,
Equation

P _t : maximum transmit power
G _t : antenna transmission gain
G _r : Antenna reception gain
λ: wavelength
δ ₀ : backscattering index
△x: required distance resolution
△y: Required orientation resolution
k: Boltzmann constant
To calculate the SNR by
SAR image formation possible area analysis device. The method of claim 1,
The maximum video time calculation unit,
Equation

λ: wavelength
R: distance
v: platform speed
△y: Required orientation resolution
θ: angle
To calculate the SAT by
SAR image formation possible area analysis device. The method of claim 3,
The maximum video time calculation unit,
Equation

x', y': coordinates of the region of interest
h: height of the vehicle
To calculate the R by
SAR image formation possible area analysis device. The method of claim 3,
The maximum video time calculation unit,
Equation

θ _sq : squint angle
θ _de : Depression angle
To calculate the θ by
SAR image formation possible area analysis device. The method of claim 5,
The maximum video time calculation unit,
Equation

To calculate the θ _sq by
SAR image formation possible area analysis device. The method of claim 5,
The maximum video time calculation unit,
Equation

To calculate the θ _de by
SAR image formation possible area analysis device. The method of claim 1,
The area calculation unit,
If the calculated SAT is less than a preset SAT_max, and the calculated SNR is greater than a preset SNR_required, it is determined as a distribution area of the SAR image.
SAR image formation possible area analysis device. Setting a first parameter of a Synthetic Aperture Radar (SAR) image for a region of interest to be acquired, and setting a second parameter for calculating an image forming region;
Calculating an image quality (SNR) for the region of interest based on the set first parameter,
Calculating a maximum image formation time (SAT) for the region of interest based on the set second parameter; and
Calculating a distribution area of the SAR image based on the set first parameter and the second parameter and the calculated SNR and the SAT
A method for analyzing a formable region of the SAR image comprising a. The method of claim 9,
Displaying the calculated distribution area of the SAR image on a display panel
A method for analyzing a formable region of the SAR image further comprising a. The method of claim 9,
The step of calculating the distribution area,
If the calculated SAT is less than a preset SAT_max, and the calculated SNR is greater than a preset SNR_required, it is calculated as the distribution area of the SAR image.
A method of analyzing the formable area of the SAR image. As a computer-readable recording medium storing a computer program that allows a processor to perform a method for analyzing a formable area of a SAR image,
The method for analyzing the formable area,
Setting a first parameter of a Synthetic Aperture Radar (SAR) image for a region of interest to be acquired, and setting a second parameter for calculating an image forming region;
Calculating an image quality (SNR) for the region of interest based on the set first parameter,
Calculating a maximum image formation time (SAT) for the region of interest based on the set second parameter; and
Comprising the step of calculating a distribution area of the SAR image based on the set first parameter and the second parameter, the calculated SNR and the SAT
Computer-readable recording media.

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