JP2016206152A - Wave radar device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wave radar device that makes it easy to intuitively image wave conditions.SOLUTION: A wave radar device comprises; an echo image generator unit 12 configured to generate an echo image in an image generation area; an analysis area echo image extraction unit 13 configured to extract echo images of analysis areas, which are sub areas of the image generation area, from the echo image generated by the echo image generator unit 12; a computation unit 17 configured to calculate water height at each point in the image generation area based on the analysis area echo images as the echo images of the analysis areas; and an overhead image generator unit configured to generate an overhead image of waves based on the water height calculated by the water height computation unit 17 and to make the overhead image displayed on a display.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a wave radar device that displays a wave image.

  Conventionally, for example, a display method as disclosed in Non-Patent Document 1 is known as a method of displaying wave information at each point within a predetermined range on the sea. In the image disclosed in Non-Patent Document 1, an arrow is displayed corresponding to each point on the sea. The direction of the arrow indicates the direction of the wave (wave direction), and the background color of each arrow corresponds to the height of the wave (wave height). Thereby, the user can know the wave direction and wave height of the waves.

NTT Resonant Co., Ltd., “go weather”, [online], [Search January 20, 2015], Internet, <http://weather.goo.ne.jp/wave/>

  By the way, on the display screen as described above, it may be difficult to intuitively imagine an actual wave situation.

  The present invention is to solve the above-described problems, and an object of the present invention is to provide a wave radar device that makes it easy to intuitively imagine a wave situation.

  (1) In order to solve the above problem, a wave radar device according to an aspect of the present invention generates a wave image based on a reception signal generated from a reflected wave of a transmission wave transmitted from a transmission unit. A radar device that generates an echo image in an image generation region in which the wave image is generated; and the echo image generated from the echo image generated by the echo image generation unit. An echo image extraction unit in the analysis region that extracts an echo image in the analysis region, which is a partial region of the region, and various regions in the image generation region based on the echo image in the analysis region as an echo image in the analysis region Based on the water surface height calculation unit that calculates the height of the water surface at the point and the water surface height calculated by the water surface height calculation unit, an overhead image as the wave image is generated, and It includes a bird's eye view image generating unit for displaying an image on a display device, a.

  (2) Preferably, the wave radar device further includes a wave component extraction unit that extracts a wave component that is a component caused by a wave based on the echo image in the analysis region, and the water surface height calculation unit includes: The height of the water surface is calculated based on the echo image in the analysis region from which the wave component has been extracted.

  (3) More preferably, the wave radar device calculates a wave characteristic that is a characteristic relating to a wave included in the in-analysis region echo image based on the in-analysis region echo image from which the wave component is extracted. The water surface height calculation unit further includes a characteristic calculation unit, and calculates the height of the water surface based on the wave characteristic calculated by the wave characteristic calculation unit.

  (4) More preferably, the echo image generation unit generates a plurality of echo images based on reception signals generated from the reflected waves received at different timings, and extracts the echo image in the analysis region The unit extracts the echo image within the analysis region from each of the plurality of echo images, and the wave characteristic calculation unit is configured to extract the plurality of echo images within the analysis region extracted by the echo image extraction unit within the analysis region. The wave angular frequency in the analysis area is calculated as the wave characteristic.

  (5) Preferably, the number, position, and size of the analysis area are preset.

  (6) Preferably, the wave radar device includes an analysis region receiving unit that receives the user's operation so that the user can set at least one of the number, position, and size of the analysis regions. In addition.

  (7) Preferably, the wave radar device includes an analysis region setting unit that sets at least one of the number, position, and size of the analysis regions according to an echo image in the image generation region. In addition.

  (8) More preferably, the analysis region setting unit includes the number, position, and size of the analysis regions so as to include a portion of the echo image in the image generation region where the echo intensity is a predetermined value or more. At least one of the above is set.

  (9) Preferably, the wave radar device further includes a wave height calculation unit that calculates a wave height that is a height of a wave included in the analysis region echo image, based on the analysis region echo image, and the water surface When the wave height calculated by the wave height calculation unit is lower than a predetermined value, the height calculation unit excludes a wave having the wave height from a target for calculating the height of the water surface by the water surface height calculation unit. .

  (10) Preferably, the wave radar device further includes a display for displaying the overhead image generated by the overhead image generation unit.

  ADVANTAGE OF THE INVENTION According to this invention, the wave radar apparatus which is easy to image a wave condition intuitively can be provided.

1 is a block diagram of a wave radar device according to an embodiment of the present invention. It is a block diagram which shows the structure of the water surface height calculation process part shown in FIG. It is a figure which shows typically the echo image produced | generated by the echo image production | generation part shown in FIG. It is a block diagram which shows the structure of the bird's-eye view image generation process part shown in FIG. It is a figure which shows typically a part of three-dimensional model of the wave produced | generated by the three-dimensional model production | generation part shown in FIG. It is a figure for demonstrating the process in which an overhead image production | generation part produces | generates an overhead image. It is a figure which shows an example of the bird's-eye view image displayed on a display. It is a figure which shows an example of the bird's-eye view image displayed on a display, Comprising: It is the figure seen from the viewpoint different from FIG. It is a figure which shows an example of the wave image displayed on a display, Comprising: It is a top view of the wave looked down at the wave from the upper direction. It is a block diagram which shows the structure of the water surface height calculation process part of the wave radar apparatus which concerns on a modification. It is a block diagram which shows the structure of the water surface height calculation process part of the wave radar apparatus which concerns on a modification. It is a block diagram which shows the structure of the water surface height calculation process part of the wave radar apparatus which concerns on a modification. It is a block diagram which shows the structure of the bird's-eye view image generation process part of the wave radar apparatus which concerns on a modification. It is a figure which shows typically a part of three-dimensional model of the wave produced | generated by the three-dimensional model production | generation part shown in FIG.

  Hereinafter, embodiments of a wave radar apparatus according to the present invention will be described with reference to the drawings. The present invention can be widely applied as a wave radar device that displays a wave image.

  FIG. 1 is a block diagram of a wave radar device 1 according to an embodiment of the present invention. The wave radar device 1 according to the present embodiment is provided in a ship such as a fishing boat. According to the wave radar device 1, the height of the water surface at each point on the sea can be calculated.

  As shown in FIG. 1, the wave radar device 1 includes an antenna unit 2, a signal processing unit 10, and a display 4.

  The antenna unit 2 includes an antenna 5, a receiving unit 6, and an A / D conversion unit 7.

  The antenna 5 is a radar antenna capable of transmitting a pulsed radio wave having strong directivity. The antenna 5 is configured to receive a reflected wave from a target (a wave in the case of the present embodiment). The wave radar device 1 measures the time from when a pulsed radio wave is transmitted to when a reflected wave is received. Thereby, the wave radar apparatus 1 can detect the distance r to the target. The antenna 5 is configured to be able to rotate 360 ° on a horizontal plane. The antenna 5 is configured to repeatedly transmit and receive radio waves while changing the transmission direction of pulsed radio waves (changing the antenna angle). With the above configuration, the wave radar device 1 can detect a target on a plane around the ship over 360 °.

  The receiving unit 6 detects and amplifies an echo signal obtained from an echo received by the antenna 5. The reception unit 6 outputs the amplified echo signal to the A / D conversion unit 7. The A / D converter 7 samples an analog echo signal and converts it into digital data (echo data) consisting of a plurality of bits. Here, the echo data includes data for specifying the intensity (signal level) of the echo signal received by the antenna 5. The A / D conversion unit 7 outputs the echo data to the signal processing unit 10.

  The signal processing unit 10 includes a water surface height calculation processing unit 11 and an overhead image generation processing unit 20.

  FIG. 2 is a block diagram illustrating a configuration of the water surface height calculation processing unit 11 illustrated in FIG. 1. The water surface height calculation processing unit 11 uses the echo data output from the antenna unit 2 to calculate the water surface height at each point on the sea based on a predetermined method described in detail below.

  As shown in FIG. 2, the water surface height calculation processing unit 11 includes an echo image generation unit 12, an in-analysis region echo image extraction unit 13, a frequency analysis unit 14, a wave component extraction unit 15, and a wave characteristic calculation unit. 16 and a water surface height calculation unit 17.

  FIG. 3 is a diagram schematically showing an echo image P1 generated by the echo image generation unit 12. As shown in FIG. The echo image generation unit 12 generates an echo image P1 of a horizontal plane including the own ship based on the echo data output from the antenna unit 2. The echo image generation unit 12 sequentially generates echo images P1 based on echo data from all directions centered on the ship obtained at regular intervals. That is, the echo image generation unit 12 generates a plurality of echo images P1 by generating the echo images P1 at regular intervals. FIG. 3 shows an example in which a plurality of wavy lines w are displayed in the echo image P1.

  The in-analysis region echo image extraction unit 13 is an analysis region that is a partial region of the image generation region Z1 from the region (image generation region Z1) in which the echo image P1 is generated by the echo image generation unit 12. An echo image in Z2 (an echo image P2 in the analysis area) is extracted. In the present embodiment, the in-analysis region echo image extraction unit 13 selects six locations near the own ship based on the own ship as the analysis region Z2. In the present embodiment, the number, position, and size of the analysis region Z2 are set in advance. The six analysis regions Z2 are arranged at the same angular interval centered on the own ship as viewed from above (in this embodiment, at an interval of 60 degrees). The in-analysis region echo image extraction unit 13 extracts six in-analysis region echo images P2 for each of the plurality of echo images P1 generated by the echo image generation unit 12.

  The frequency analysis unit 14 performs frequency analysis on the analysis region echo image P2 obtained by the analysis region echo image extraction unit 13. Specifically, the frequency analysis unit 14 performs a three-dimensional fast Fourier transform (3DFFT) process on the plurality of in-analysis region echo images P2. This makes it possible to generate three-dimensional data in which the x-axis and y-axis units are rad / m and the z-axis unit is rad / sec.

  The wave component extraction unit 15 extracts a wave component that is a component caused by the wave from the three-dimensional data obtained by the frequency analysis unit 14. Specifically, the wave component extraction unit 15 uses only information on the spectrum close to the wave dispersion relational expression expressed by the following equations (1) and (2) in the three-dimensional data, Extract the wave component.

[Equation 1]
ω ² = gKtanh (Kd) (1)

[Equation 2]
ω ² = gK (2)

  However, Expression (2) is an expression used when the water depth is sufficiently deep, specifically, when the water depth is longer than a half wavelength, and in other cases, Expression (1) is used.

  The wave characteristic calculation unit 16 is a characteristic regarding waves in the analysis region Z2 based on the analysis region echo image P2 extracted by the analysis region echo image extraction unit 13 and the three-dimensional data obtained by the frequency analysis unit 14. Calculate certain wave characteristics. In the present embodiment, wave height α, wave number K, wave direction θ, and angular frequency ω are calculated as wave characteristics.

  The wave characteristic calculation unit 16 calculates the above-described wave characteristic (wave height α, wave number K, wave direction θ, and angular frequency ω), for example, as follows. Specifically, the wave characteristic calculation unit 16 calculates the wave height α based on the wave echo intensity displayed in the analysis region echo image P2. Moreover, the wave characteristic calculation part 16 calculates the wave number K based on the space | interval of the wavy line displayed on the echo image P2 in an analysis area | region. Further, the wave characteristic calculation unit 16 determines the wave direction θ as a directional frequency spectrum derived from the three-dimensional data obtained by the frequency analysis unit 14 (the circumferential direction corresponds to the wave direction and the radial direction corresponds to the wave frequency. The wave direction θ is calculated based on the spectrum plotted on the polar coordinates). Further, the wave characteristic calculation unit 16 calculates the angular frequency ω based on the directional frequency spectrum.

  Note that some of the above-described wave characteristics are calculated using the three-dimensional data obtained by the three-dimensional fast Fourier transform processing as described above, so that the calculation load for calculating the wave characteristics is not limited. Is relatively large. For this reason, in the wave characteristic calculation part 16, each wave characteristic mentioned above is calculated for every second as an example, for example.

  The water surface height calculation unit 17 uses each wave characteristic calculated by the wave characteristic calculation unit 16 and each point in the region where the wave image is generated at every predetermined time t based on the following equation (3). The height η of the water surface at (x, y) is calculated. For example, the water surface height calculation unit 17 calculates the height η of the water surface at all points of the wave image, for example, 24 times per second.

[Equation 3]
η (x, y, t) = α ₁ cos (xK ₁ cos θ ₁ + yK ₁ sin θ ₁ + ω ₁ t + ε ₁ )
+ Α ₂ cos (xK ₂ cos θ ₂ + yK ₂ sin θ ₂ + ω ₂ t + ε ₂ )
+ Α ₃ cos (xK ₃ cos θ ₃ + yK ₃ sin θ ₃ + ω ₃ t + ε ₃ )
... + α _N cos (xK _N cos θ _N + yK _N sin θ _N + ω _N t + ε _N )
... (3)

  Each term in Formula (3) is, for example, the height of the water surface based on waves included in each analysis region Z2 (six analysis regions shown in FIG. 3 in the present embodiment) as an example. That is, in Equation (3), assuming that the waves included in each analysis region Z2 exist over the entire image generation region Z1, the height η of the water surface at each point in the entire image generation region Z1 is calculated. doing. In addition, ε in equation (3) is the initial phase of the waves. In the expression (3), the same processing as the three-dimensional inverse Fourier transform is performed. Specifically, the height η of the water surface in Equation (3) corresponds to the signal intensity in the three-dimensional inverse Fourier transform.

  Further, the water surface height calculation unit 17 uses the wave characteristic values (wave height α, wave number K, wave direction θ, and angular frequency ω) that are updated as needed, and the height η of the water surface at all points of the wave image. Is calculated. In the present embodiment, since the value of the wave characteristic is calculated every second, the water surface height calculation unit 17 uses the equation (3) in which the value of each wave characteristic updated every second is substituted. The height η of the water surface at each point (x, y) is calculated.

  FIG. 4 is a block diagram illustrating a configuration of the overhead image generation processing unit 20 illustrated in FIG. The bird's-eye view image generation processing unit 20 obtains the data of the wave bird's-eye view image (an image obtained by viewing the wave obliquely from above) based on the height η of the water surface at each point on the sea obtained by the water surface height calculation processing unit 11. Generate.

  As shown in FIG. 3, the overhead image generation processing unit 20 includes a three-dimensional model generation unit 21, a viewpoint position determination unit 22, a light source position determination unit 23, and an overhead image generation unit 24.

FIG. 5 is a diagram schematically showing a part of a three-dimensional wave model generated by the three-dimensional model generation unit 21. With reference to FIG. 5, the three-dimensional model generation unit 21 outputs the water surface height η (x, y, t _n ) (where n = 1, 1) output from the water surface height calculation processing unit 11. 2), a three-dimensional model M of waves at each time is generated. Specifically, the three-dimensional model generation unit 21 determines the length of the line segment L extending vertically from each position (x, y) on the xy plane at each position (x, y) at a certain time t _n . Draw in correspondence with the height η of the water surface. 3D model generation unit 21, for each time t _n, to generate a three-dimensional model M of wave. That is, in the present embodiment, the three-dimensional model generation unit 21 generates the wave three-dimensional model M 24 times per second. In the example shown in FIG. 5, a spherical portion is provided at the tip of each line segment L so that the user can easily recognize the water surface position. The water surface shape is simulated by the spherical portion. The three-dimensional model M generated by the three-dimensional model generation unit 21 is output to the overhead image generation unit 24.

  The viewpoint position determination unit 22 determines a viewpoint position VP (see FIG. 6) when the wave 3D model M generated by the 3D model generation unit 21 is displayed on the display 4. For example, the viewpoint position determination unit 22 determines a position with respect to the three-dimensional model M set by the user using an operation device (not shown) such as a keyboard or a mouse as the viewpoint position VP, and generates the overhead image. Notification to the unit 24.

  The light source position determination unit 23 displays the light source position LP of the light irradiated to the three-dimensional model M when displaying the three-dimensional model M of the waves generated by the three-dimensional model generation unit 21 on the display 4 (see FIG. 6). ). For example, the light source position determination unit 23 determines a position with respect to the three-dimensional model M set by the user using an operation device (not shown) such as a keyboard or a mouse as the light source position LP, and generates the overhead image. Notification to the unit 24.

  FIG. 6 is a diagram for explaining a process of generating an overhead image by the overhead image generation unit 24. The overhead image generation unit 24 is based on the 3D model M output from the 3D model generation unit 21, the viewpoint position VP notified from the viewpoint position determination unit 22, and the light source position LP notified from the light source position determination unit 23. Generate a bird's-eye view of waves. Specifically, the overhead image generation unit 24 projects an image when the three-dimensional model M in a state irradiated with light from the light source arranged at the light source position LP is viewed from the viewpoint position VP on the two-dimensional plane PL. This figure is generated as an overhead image.

  FIG. 7 is a diagram illustrating an example of an overhead image displayed on the display 4. On the display 4, an overhead image based on the overhead image data output from the overhead image generation unit 24 is displayed. As described above, the display 4 of the wave radar device 1 according to the present embodiment displays a three-dimensional image as if the ocean waves are viewed from diagonally above. This makes it easy for the user to intuitively imagine the state of waves at each point on the sea. Note that the bird's-eye view image shown in FIG. 7 is a bird's-eye view image when the viewpoint from the wheelhouse of the ship is the viewpoint position.

  Then, in the wave radar device 1 according to the present embodiment, 24 bird's-eye view images shown in FIG. 7 are generated per second, so that the display 4 displays a wave image with a frame rate of 24 fps. . In the wave radar apparatus 1, the values of wave characteristics (wave height α, wave number K, wave direction θ, and angular frequency ω), which are information about waves, are set at relatively short intervals (in this embodiment, at intervals of 1 second). Calculated). That is, in the radar apparatus, the height of the water surface is calculated based on the value of the wave characteristic in a state close to real time, so that the user can confirm the wave image similar to the actual wave on the display 4.

  In the wave radar apparatus 1, the viewpoint of the overhead image can be switched by the user appropriately operating an operation panel (not shown) or the like. FIG. 8 is an overhead image when the viewpoint position is changed upward from the overhead image shown in FIG. 7. Furthermore, in the wave radar device 1, the user can appropriately switch the display screen to a view (wave plane image) of the wave viewed from above (see FIG. 9) by appropriately operating the operation panel or the like.

[effect]
As described above, in the wave radar device 1 according to the present embodiment, the wave image displayed on the display 4 is three-dimensionally displayed as an overhead image. Thereby, as compared with the case where the wave height and direction are illustrated two-dimensionally as in Non-Patent Document 1 described above, the state of the wave can be grasped at a glance.

  Therefore, according to the wave radar device 1, it is possible to provide a wave radar device that makes it easy to intuitively imagine a wave situation.

  Further, the wave radar device 1 calculates the height η of the water surface at each point in the entire image generation region Z1 based on the echo image P2 in the analysis region Z2 that is a part of the image generation region Z1. Based on the height η, a bird's-eye view image of a wave is generated. That is, the wave radar device 1 can generate a bird's-eye view image displayed three-dimensionally based on the actually obtained wave echo. Thereby, the user can grasp | ascertain the state of an actual wave correctly.

  In the wave radar device 1, the height η of the water surface at each point in the entire image generation region Z1 is calculated based on the echo image P2 in the analysis region Z2 that is a part of the image generation region Z1. That is, in the wave radar device 1, the calculation load on the signal processing unit 10 can be reduced as compared with the case where the water surface height η at each point is calculated based on the echo image P1 of the entire image generation region Z1.

  Moreover, in the wave radar apparatus 1, the height η of the water surface is calculated based on the analysis region echo image P2 from which the wave component is extracted. As a result, the water surface height η can be calculated based on the in-analysis region echo image P2 in a state in which unnecessary echoes (for example, echoes from the land as an example) are eliminated, so that the water surface height η is accurately calculated. it can.

  Further, in the wave radar device 1, the entire image generation region Z 1 is based on the wave characteristics calculated by the wave characteristic calculation unit 16, specifically, the wave height α, wave number K, wave direction θ, and angular frequency ω. The height η of the water surface at each point is calculated. That is, according to the wave radar device 1, the wave characteristic data obtained from a part of the region Z2 can be extended to the entire image generation region Z1.

  Further, the wave radar device 1 can calculate the angular frequency ω of the waves based on the plurality of in-analysis region echo images P2. Thereby, the angular frequency ω can be calculated appropriately.

  In the wave radar device 1, the analysis region Z2 is set in advance. As a result, it is possible to save the user from setting the analysis region Z2 separately.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention.

  (1) FIG. 10 is a block diagram illustrating a configuration of a water surface height calculation processing unit 11a of a wave radar device according to a modification. In the wave radar device 1 according to the above-described embodiment, the number, position, and size of the analysis region Z2 are set in advance, but the present invention is not limited to this. Specifically, a wave radar device in which the number, position, and size of the analysis region Z2 can be set by a user operation may be configured. As shown in FIG. 10, the water surface height calculation processing unit 11a of the wave radar device according to this modification further includes an analysis region receiving unit 18.

  The analysis region receiving unit 18 receives the number, position, size, and the like of the analysis region Z2 set by the user appropriately operating an operation panel (not shown), and sends them to the analysis region echo image extraction unit 13. Notice. The analysis region echo image extraction unit 13 extracts the analysis region echo image P2 using the analysis region Z2 set based on the number, position, and size of the analysis region Z2 notified from the analysis region reception unit 18. To do.

  As described above, according to this modification, the user can set the position of the analysis region Z2 and the like. Then, for example, the user can select a portion having a high wave height (a portion having a high echo intensity) by looking at the echo image of the waves displayed on the display device 4. Thereby, since the calculation of the wave characteristic of a large wave that has a great influence on the ship and the like can be prevented and the wave characteristic can be reliably calculated, the large wave can be displayed on the overhead image.

  (2) FIG. 11 is a block diagram illustrating a configuration of the water surface height calculation processing unit 11b of the wave radar device according to the modification. In the wave radar device 1 according to the above-described embodiment, the number, position, and size of the analysis region Z2 are set in advance, but the present invention is not limited to this. Specifically, the number, position, and size of the analysis region Z2 may be set on the wave radar device side. The water surface height calculation processing unit 11b of the wave radar device according to this modification further includes an analysis region setting unit 19 as shown in FIG.

  The analysis region setting unit 19 determines the number, position, and size of the analysis region Z2 based on the echo image P1 generated by the echo image generation unit 12. Specifically, the analysis region setting unit 19 determines the number, position, and size of analysis regions so as to include a portion where the echo intensity in the echo image P1 is equal to or greater than a predetermined value.

  As described above, according to the present modification, a portion where the echo intensity is equal to or greater than the predetermined value can be surely included in the analysis region Z2, so that the portion is excluded from the target for calculating the wave characteristics. Can be prevented. That is, in this modification, it can prevent that a big wave is excluded from a bird's-eye view image.

  (3) FIG. 12 is a block diagram illustrating a configuration of the water surface height calculation processing unit 11c of the wave radar device according to the modification. In the wave radar device 1 according to the above-described embodiment, the bird's-eye view image of the wave is generated based on all the waves whose wave characteristics are calculated, but the present invention is not limited to this. Specifically, in the wave radar device according to this modification, among the wave heights calculated by the wave characteristic calculation unit 16, the wave component having a wave height whose value is equal to or less than a predetermined value is used as a bird's-eye view image of the wave. Is excluded from the target of generating.

  The water surface height calculation processing unit 11 c of the wave radar device according to this modification includes a low wave height component removing unit 28. The low wave height component removing unit 28 compares the wave height value calculated by the wave characteristic calculating unit 16 with the stored predetermined value. Then, the low wave height component removing unit 28 excludes a wave component having a wave height lower than a predetermined value from a target for generating a wave overhead image. According to this modified example, since the low-wave height waves that have little influence on the ship and the like can be excluded from the waves that are the targets for generating the overhead image, the overhead image can be prevented from becoming complicated, and the signal processing unit Calculation load can be reduced.

  (4) FIG. 13 is a block diagram illustrating a configuration of the overhead image generation processing unit 20a of the wave radar device according to the modification. FIG. 14 is a diagram schematically showing a part of a three-dimensional wave model generated by the three-dimensional model generation unit 21a shown in FIG.

  In the three-dimensional model generation unit 21a of the present modification, first, as in the case of the above-described three-dimensional model generation unit 21a, the length of the line segment L extending vertically from each position (x, y) on the xy plane is set to the sea level. Are drawn in correspondence with the water surface height η at each position (x, y). Then, in the three-dimensional model generation unit 21a of this modification, the surface generation unit 21b generates a surface model of the water surface position. Specifically, as illustrated in FIG. 14, the surface generation unit 21 b generates, for all the line segments L, a triangular plane that passes through the apexes of the three adjacent line segments L. As a result, the wave shape is represented in a pseudo manner by a large number of triangular planes generated by the surface generation unit 21b. In FIG. 13, the line segment L is illustrated, but this line segment L may be omitted from the overhead image.

1 Wave Radar Device 4 Display 5 Antenna (Wave Transmitter)
17 Water surface height calculation unit 24 Overhead image generation unit P2 Echo image in analysis area Z1 Image generation area Z2 Analysis area

Claims (10)

A wave radar device that generates a wave image based on a reception signal generated from a reflected wave of a transmission wave transmitted from a transmission unit,
An echo image generation unit for generating an echo image in an image generation region in which the wave image is generated;
From the echo image generated by the echo image generation unit, an echo image extraction unit in an analysis region that extracts an echo image in an analysis region that is a partial region of the image generation region;
Based on the echo image in the analysis region as the echo image in the analysis region,
Based on the height of the water surface calculated by the water surface height calculation unit, an overhead image generation unit that generates the overhead image as the wave image and displays the overhead image on a display device;
A wave radar device comprising: The wave radar device according to claim 1,
Based on the echo image in the analysis region, further comprising a wave component extraction unit that extracts a wave component that is a component caused by waves,
The water radar apparatus according to claim 1, wherein the water surface height calculation unit calculates the height of the water surface based on the echo image in the analysis area from which the wave component is extracted. The wave radar device according to claim 2,
Based on the analysis region echo image from which the wave component has been extracted, further includes a wave characteristic calculation unit that calculates a wave characteristic that is a property related to the wave included in the analysis region echo image,
The water radar apparatus according to claim 1, wherein the water surface height calculation unit calculates the height of the water surface based on the wave characteristics calculated by the wave characteristic calculation unit. In the wave radar device according to claim 3,
The echo image generation unit generates a plurality of echo images based on reception signals generated from the reflected waves received at different timings,
The analysis area echo image extraction unit extracts the analysis area echo image from each of the plurality of echo images,
The wave characteristic calculation unit calculates an angular frequency of waves in the analysis region as the wave characteristic based on the plurality of analysis region echo images extracted by the analysis region echo image extraction unit. A wave radar device. In the wave radar device according to any one of claims 1 to 4,
A wave radar apparatus, wherein the number, position, and size of the analysis area are preset. In the wave radar device according to any one of claims 1 to 4,
A wave radar, further comprising: an analysis region receiving unit that receives the user's operation so that the user can set at least one of the number, position, and size of the analysis region. apparatus. In the wave radar device according to any one of claims 1 to 4,
A wave radar, further comprising: an analysis region setting unit that sets at least one of the number, position, and size of the analysis region according to an echo image in the image generation region apparatus. In the wave radar device according to claim 7,
The analysis region setting unit includes at least one of the number, position, and size of the analysis regions so as to include a portion of the echo image in the image generation region that has an echo intensity equal to or greater than a predetermined value. A wave radar device, characterized in that In the wave radar device according to any one of claims 1 to 8,
Based on the analysis region echo image, further comprising a wave height calculation unit that calculates a wave height that is the height of the waves included in the analysis region echo image,
When the wave height calculated by the wave height calculation unit is lower than a predetermined value, the water surface height calculation unit is configured to calculate a wave having the wave height from a target for calculating the height of the water surface by the water surface height calculation unit. A wave radar device characterized in that it is excluded. The wave radar device according to any one of claims 1 to 9,
A wave radar device, further comprising a display for displaying the overhead image generated by the overhead image generation unit.