Radar device, data processing method, and data processing program

Abstract

To display a plurality of targets that are close to each other separately in an echo image while reducing the memory capacity required for displaying the echo image.SOLUTION: A radar device includes a transmitting unit that transmits radar waves, a receiving unit that receives reflected waves of the radar waves reflected by a target, a generating unit that generates, based on the reflected waves, amplitude data of the reflected waves and displacement data of the target for each cell on a coordinate system having azimuth and distance directions as coordinate axes, and a determining unit that performs a determination process to determine, based on a comparison result between the displacement data of a target cell and the displacement data of a cell close to the target cell, whether the target cell corresponds to a boundary cell, which is a cell that serves as a boundary separating the different targets.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a radar device, a data processing method, and a data processing program. [Background technology]

[0002] Conventionally, in a radar device that displays an echo image of a target, a technique for improving the resolution of the detection result of the target has been developed. For example, Patent Document 1 (International Publication No. 2014 / 142088) describes the following radar device. That is, the radar device includes a radar wave transmitting unit that transmits radar waves at a predetermined interval while rotating in an azimuth direction, a radar wave receiving unit that receives the radar waves reflected by a target, an analysis processing unit that analyzes radar wave data received by the radar wave receiving unit, stores amplitude data and speed data of the target or amplitude data and acceleration data of the target on a predetermined coordinate for each cell, and processes amplitude data of a cell of interest on the coordinate having a speed or acceleration based on these data, and a radar display data output unit that outputs the amplitude data processed by the analysis processing unit as radar display data, and the analysis processing unit determines whether or not the absolute value of the speed difference or acceleration difference between adjacent cells adjacent to the cell of interest across the cell of interest is equal to or greater than a threshold value, and performs a process of reducing the amplitude data of the cell of interest if the absolute value is equal to or greater than the threshold value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2014 / 142088 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a need for a technology that goes beyond the technology described in Patent Document 1 and that is capable of separately displaying multiple nearby targets in an echo image while reducing the memory capacity required to display the echo image.

[0005] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a radar device, a data processing method, and a data processing program that are capable of separately displaying multiple close targets in an echo image while reducing the memory capacity required to display the echo image. [Means for solving the problem]

[0006] (1) In order to solve the above problems, a radar device according to one aspect of the present invention includes a transmitting unit that transmits radar waves; a receiving unit that receives reflected waves of the radar waves reflected by a target; a generating unit that generates, based on the reflected waves, amplitude data of the reflected waves and displacement data indicating a speed or acceleration of the target for each cell on a coordinate system having azimuth and distance directions as coordinate axes; and a determining unit that performs a determining process to determine whether the target cell is a boundary cell, which is the cell that serves as a boundary separating different targets, based on a comparison result between the displacement data of a target cell of a plurality of the cells and the displacement data of a cell adjacent to the target cell in the azimuth or distance direction.

[0007] In this way, the configuration for performing the determination process of whether or not the cell of interest corresponds to a boundary cell based on the result of comparison between the displacement data of the cell of interest and the displacement data of a cell adjacent to the cell of interest in the azimuth direction or the distance direction allows the determination process to be performed using fewer displacement data of cells compared to a configuration using the displacement data of two adjacent cells sandwiching the cell of interest, thereby reducing the memory capacity required to store the displacement data used in the determination process. Also, based on the result of the determination process, multiple adjacent targets can be displayed separately in the echo image. Therefore, multiple adjacent targets can be displayed separately in the echo image while reducing the memory capacity required to display the echo image.

[0008] (2) In the above (1), the judgment unit may, in the judgment process, judge whether the target cell corresponds to the boundary cell based on a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the azimuth direction, and a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the distance direction.

[0009] With this configuration, it is possible to more accurately determine whether the cell of interest is a boundary cell or not.

[0010] (3) In (2) above, the judgment unit may determine that the target cell corresponds to the boundary cell if, in the judgment process, an absolute value of a difference between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the azimuth direction is greater than or equal to a predetermined value, and an absolute value of a difference between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the distance direction is greater than or equal to a predetermined value.

[0011] With this configuration, it is possible to determine by simple processing whether or not the target cell corresponds to a boundary cell using a preset threshold value.

[0012] (4) In any of (1) to (3) above, the transmitter may repeatedly transmit the radar wave while changing the transmission direction of the radar wave along a first direction among the azimuth directions, and the judgment unit may, in the judgment process, judge whether the cell of interest corresponds to the boundary cell based on a comparison result between the displacement data of the cell of interest and the displacement data of the cell adjacent to the cell of interest in a direction opposite to the first direction.

[0013] With this configuration, displacement data for cells in each row along the first direction can be generated sequentially, and it can be determined whether a cell in the latest row is a boundary cell or not, thereby suppressing delays in displaying echo images using amplitude data that are caused by performing the determination process.

[0014] (5) In the above (4), the judgment unit may perform the judgment process while changing the cell set as the target cell along a second direction of the distance directions, and in the judgment process, the judgment unit may determine whether the target cell corresponds to the boundary cell or not based on a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the second direction.

[0015] With this configuration, it is possible to prevent the cell at the leading edge of the target on the radar device side in the distance direction from being judged as a boundary cell in the judgment process, so that, based on the results of the judgment process, it is possible to more accurately recognize the boundary on the radar device side in the echo image of the target that is located further back from the radar device than two nearby targets.

[0016] (6) In any one of (1) to (5) above, the radar device may further include a reduction processing unit that reduces an amplitude indicated by the amplitude data of the cell of interest that is determined to correspond to the boundary cell.

[0017] With this configuration, an echo image is generated based on amplitude data with reduced amplitude, making it possible to display a plurality of closely spaced targets separately.

[0018] (7) In order to solve the above problems, a data processing method according to one aspect of the present invention is a data processing method in a radar device, which transmits radar waves, receives waves reflected by a target, and generates, based on the reflected waves, amplitude data of the reflected waves and displacement data indicating the speed or acceleration of the target for each cell on a coordinate system having azimuth and distance directions as coordinate axes. Based on a comparison result between the displacement data of a target cell among a plurality of cells and the displacement data of a cell adjacent to the target cell in the azimuth or distance direction, a determination process is performed to determine whether the target cell is a boundary cell, which is the cell that serves as a boundary separating different targets.

[0019] In this way, by performing a determination process of determining whether or not a cell of interest corresponds to a boundary cell based on a comparison result between the displacement data of the cell of interest and the displacement data of a cell adjacent to the cell of interest in the azimuth direction or the distance direction, the determination process can be performed using fewer displacement data of cells compared to a method using the displacement data of two adjacent cells sandwiching the cell of interest, so that the memory capacity required to store the displacement data used in the determination process can be reduced. Also, based on the result of the determination process, multiple adjacent targets can be displayed separately in the echo image. Therefore, multiple adjacent targets can be displayed separately in the echo image while reducing the memory capacity required to display the echo image.

[0020] (8) In order to solve the above-mentioned problems, a data processing program according to one aspect of the present invention is a data processing program used in a radar device, and causes a computer to execute the following processes: transmitting radar waves; receiving reflected waves of the radar waves reflected by a target; generating, based on the reflected waves, amplitude data of the reflected waves and displacement data indicating the speed or acceleration of the target for each cell on a coordinate system having azimuth and distance directions as coordinate axes; and performing a determination process to determine whether the target cell is a boundary cell, which is the cell that serves as a boundary separating different targets, based on a comparison result between the displacement data of a target cell among a plurality of the cells and the displacement data of a cell adjacent to the target cell in the azimuth or distance direction.

[0021] In this way, the configuration for performing the determination process of whether or not the cell of interest corresponds to a boundary cell based on the result of comparison between the displacement data of the cell of interest and the displacement data of a cell adjacent to the cell of interest in the azimuth direction or the distance direction allows the determination process to be performed using fewer displacement data of cells compared to a configuration using the displacement data of two adjacent cells sandwiching the cell of interest, thereby reducing the memory capacity required to store the displacement data used in the determination process. Also, based on the result of the determination process, multiple adjacent targets can be displayed separately in the echo image. Therefore, multiple adjacent targets can be displayed separately in the echo image while reducing the memory capacity required to display the echo image. Effect of the Invention

[0022] According to the present invention, it is possible to reduce the memory capacity required for displaying an echo image, while separately displaying a plurality of adjacent targets in the echo image. [Brief description of the drawings]

[0023] [Figure 1] FIG. 1 is a diagram showing a detection target area of ​​a radar device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing an example of an echo image displayed by the radar device according to the embodiment of the present invention. [Diagram 3] FIG. 3 is a diagram showing a configuration of a radar device according to an embodiment of the present invention. [Figure 4] FIG. 4 is a diagram for explaining a process of generating amplitude data and velocity data by a generating unit in a radar device according to an embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram for explaining an example of a determination process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 6] FIG. 6 is a diagram showing an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 7] FIG. 7 is a diagram illustrating an example of a determination process and a correction process performed by a radar device according to a comparative example. [Figure 8] FIG. 8 is a diagram showing another example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 9] FIG. 9 is a diagram illustrating another example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing another example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 11] FIG. 11 is a diagram showing another example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 12] FIG. 12 is a diagram illustrating another example of the determination process and the correction process by the data processing unit in the radar device according to the comparative example. [Figure 13] FIG. 13 is a diagram illustrating another example of the determination process and the correction process by the data processing unit in the radar device according to the comparative example. [Figure 14]FIG. 14 is a diagram illustrating another example of the determination process and the correction process by the data processing unit in the radar device according to the comparative example. [Figure 15] FIG. 15 is a diagram illustrating another example of the determination process and the correction process by the data processing unit in the radar device according to the comparative example. [Figure 16] FIG. 16 is a diagram for explaining another example of the determination process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 17] FIG. 17 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 18] FIG. 18 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 19] FIG. 19 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 20] FIG. 20 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 21] FIG. 21 is a diagram for explaining another example of the determination process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 22] FIG. 22 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Diagram 23] FIG. 23 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 24] FIG. 24 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Diagram 25] FIG. 25 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 26]FIG. 26 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 27] FIG. 27 is a diagram for explaining another example of the determination process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 28] FIG. 28 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Figure 29] FIG. 29 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Diagram 30] FIG. 30 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Diagram 31] FIG. 31 is a diagram illustrating an example of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. [Diagram 32] FIG. 32 is a diagram showing the superiority or inferiority according to adjacent cells used in the determination process by the data processing unit in the radar device according to the embodiment of the present invention. [Diagram 33] FIG. 33 is a flowchart showing an example of an operation performed by the radar device according to the embodiment of the present invention when performing a process of displaying an echo image. [Diagram 34] FIG. 34 is a flowchart showing an example of an operation performed by the radar device according to the embodiment of the present invention when performing a determination process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference characters and their description will not be repeated. In addition, at least some of the embodiments described below may be arbitrarily combined.

[0025] [Configuration and basic operation] Fig. 1 is a diagram showing a detection target area of ​​a radar device according to an embodiment of the present invention. With reference to Fig. 1, a radar device 101 is mounted on a ship 1. The radar device 101 transmits radar waves to a detection target area Ta and receives reflected waves of the transmitted radar waves. Based on the received radar waves, the radar device 101 performs a process of displaying an echo image on a display device (not shown) showing the presence or absence of a target S such as another ship in the detection target area Ta and the distance between the radar device 101 and the target S. For example, the detection target area Ta is an area inside a circle of a predetermined size centered on the ship.

[0026] For example, the radar device 101 transmits radar waves to a divided target area Da that is a part of the detection target area Ta during a sweep period T of a predetermined length, and receives waves reflected from the transmitted electromagnetic waves. The radar device 101 repeats transmitting radar waves and receiving reflected waves while changing the azimuth angle of the radar wave transmission direction by a predetermined angle for each sweep period T. Hereinafter, changing the azimuth angle of the radar wave transmission direction by the radar device 101 by a predetermined angle is also referred to as a "sweep."

[0027] Fig. 2 is a diagram showing an example of an echo image displayed by a radar device according to an embodiment of the present invention. With reference to Fig. 2, when targets S1 and S2 are close to each other in a detection target area Ta, the targets S1 and S2 may be displayed in the echo image as a single target S. In this case, a user of the radar device 101 cannot distinguish and recognize the targets S1 and S2 based on the displayed echo image.

[0028] In this way, when multiple targets S are close to each other, a technique is desired that can separately display multiple nearby targets in an echo image while reducing the memory capacity required to display the echo image. Therefore, the radar device 101 according to the embodiment of the present invention solves the above problem by adopting the following configuration.

[0029] (Radar device) FIG. 3 is a diagram showing a configuration of a radar device according to an embodiment of the present invention. Referring to FIG. 3, the radar device 101 includes an antenna 11, a switching unit 12, a transmitting unit 13, a receiving unit 14, a generating unit 15, a storage unit 16, a data processing unit 17, and a display processing unit 18. The generating unit 15 includes an amplitude data generating unit 15A and a speed data generating unit 15B. The data processing unit 17 is an example of a determining unit and an example of a reduction processing unit. A part or all of the switching unit 12, the transmitting unit 13, the receiving unit 14, the generating unit 15, the data processing unit 17, and the display processing unit 18 are realized, for example, by a processing circuit including one or more processors. The storage unit 16 is, for example, a non-volatile memory included in the processing circuit.

[0030] The switching unit 12 alternates between a state in which the antenna 11 is connected to the transmitter 13 and a state in which the antenna 11 is connected to the receiver 14. The switching unit 12 connects the antenna 11 to the transmitter 13 during a radar wave transmission period Tt of the sweep period T, and connects the antenna 11 to the receiver 14 during a reflected wave reception period Tr of the sweep period T.

[0031] The transmitter 13 transmits radar waves via the switch 12 and the antenna 11 to the divided area Da during the transmission period Tt.

[0032] For example, the transmitter 13 repeatedly transmits radar waves while changing the transmission direction of the radar waves along the sweep direction in the azimuth direction. Hereinafter, the sweep direction is also referred to as the sweep direction. The sweep direction is a direction along the azimuth direction, for example, a clockwise direction. The sweep direction is an example of a first direction. The transmission direction of the radar waves is an example of a second direction, and is a direction away from the ship 1. More specifically, the antenna 11 rotates along the sweep direction such that the azimuth angle of the transmission direction of the radar waves changes by a predetermined angle for each sweep period T. The transmitter 13 transmits radar waves to a different division target area Da for each sweep period T via the switching unit 12 and the antenna 11.

[0033] The receiving unit 14 receives reflected waves of radar waves reflected by a target S. More specifically, during a reception period Tr, the receiving unit 14 receives reflected waves of radar waves reflected by a target S in a division target area Da via the antenna 11 and the switching unit 12. The receiving unit 14 generates reception data by digitally converting the received reflected waves for each reception period Tr, and outputs the generated reception data to the generating unit 15.

[0034] Fig. 4 is a diagram for explaining the generation process of amplitude data and speed data by a generation unit in a radar device according to an embodiment of the present invention. Fig. 4 shows a plurality of cells C arranged in a matrix on two-dimensional coordinates corresponding to a detection target area Ta. For example, one column of cells C in the two-dimensional coordinates corresponds to one division target area Da. Note that, in reality, the azimuth direction is a curved direction and the shape of the cells C is expressed using a curve, but for the sake of explanation in Fig. 4, the azimuth direction is a straight line direction and the shape of the cells C is a square. The same applies to Fig. 5 and subsequent figures.

[0035] 4, the generating unit 15 generates amplitude data of the reflected wave and speed data indicating the speed of the target S for each cell C on the coordinate system having the azimuth direction and the distance direction as coordinate axes, based on the reflected wave received by the receiving unit 14. The speed data is an example of displacement data.

[0036] More specifically, the amplitude data generating unit 15A in the generating unit 15 receives reception data from the receiving unit 14, and generates amplitude data indicating the amplitude of the reflected wave reflected at a position corresponding to the cell C based on the received reception data. For example, the amplitude data generating unit 15A generates amplitude data for one column of cells C every time it receives reception data from the receiving unit 14. Every time it generates amplitude data for one cell C, the amplitude data generating unit 15A stores the generated amplitude data in the storage unit 16 in association with the cell C. Note that the amplitude data generating unit 15A may binarize the amplitude of the reflected wave reflected at a position corresponding to the cell C using a predetermined threshold value, and generate amplitude data indicating the binarized amplitude.

[0037] Furthermore, the speed data generating unit 15B in the generating unit 15 receives reception data from the receiving unit 14, and generates speed data indicating the speed of the target S at a position corresponding to the cell C based on the received reception data. More specifically, the speed data generating unit 15B calculates the Doppler speed of the target S at a position corresponding to the cell C based on the reception data, for example, according to the pulse pair method. For example, the speed data generating unit 15B generates speed data for one row of cells C every time it receives reception data from the receiving unit 14. Every time the speed data generating unit 15B generates speed data for one cell C, it stores the generated speed data in the storage unit 16 in association with the cell C.

[0038] The data processing unit 17 performs a judgment process to determine whether or not a cell C in two-dimensional coordinates corresponds to a boundary cell Cx, which is a cell C that serves as a boundary dividing different targets S, based on the speed data stored in the memory unit 16 by the speed data generating unit 15B.

[0039] Fig. 5 is a diagram for explaining an example of a determination process by a data processing unit in a radar device according to an embodiment of the present invention. With reference to Fig. 5, the data processing unit 17 compares the speed data of a cell Ct of interest among a plurality of cells C with the speed data of cells C adjacent to the cell Ct of interest in the azimuth direction. The cells C adjacent to the cell Ct of interest in the azimuth direction are, for example, cells C less than a predetermined number of which are arranged in the azimuth direction from the cell Ct of interest. For example, the data processing unit 17 compares the speed data of the cell Ct of interest with the speed data of an adjacent cell Ca1, which is a cell C adjacent to the cell Ct of interest in the direction opposite to the sweep direction.

[0040] Furthermore, the data processing unit 17 compares the speed data of the cell of interest Ct with the speed data of a cell C adjacent to the cell of interest Ct in the distance direction. The cell C adjacent to the cell of interest Ct in the distance direction is, for example, a cell C that is less than a predetermined number of cells C arranged in the distance direction from the cell of interest Ct. For example, the data processing unit 17 compares the speed data of the cell of interest Ct with the speed data of a neighboring cell Cb1, which is a cell C adjacent to the cell of interest Ct in the transmission direction of the radar wave.

[0041] The data processing unit 17 performs a judgment process to determine whether the target cell Ct corresponds to the boundary cell Cx based on the comparison result between the speed data of the target cell Ct and the speed data of the adjacent cell Ca1, and the comparison result between the speed data of the target cell Ct and the speed data of the adjacent cell Cb1.

[0042] For example, in the judgment process, the data processing unit 17 judges that the cell of interest Ct corresponds to the boundary cell Cx if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Ca1 is greater than or equal to a predetermined value, or if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Cb1 is greater than or equal to a predetermined value.

[0043] The data processing unit 17 performs a correction process to reduce the amplitude indicated by the amplitude data of the target cell Ct determined to be the boundary cell Cx. More specifically, in the correction process, the data processing unit 17 corrects the amplitude indicated by the amplitude data of the cell C determined to be the boundary cell Cx in the memory unit 16 to zero.

[0044] For example, the data processing unit 17 performs the determination process while changing the cell C to be set as the cell of interest Ct along the transmission direction of the radar wave. More specifically, the data processing unit 17 performs the determination process and the correction process for each column of the cells C. The data processing unit 17 performs the determination process and the correction process for each cell C while changing the cell C to be set as the cell of interest Ct among the cells C in the target column from the cell C closest to the ship 1 along the transmission direction of the radar wave.

[0045] In the judgment process, the data processing unit 17 may use the speed data of the cell C adjacent to the adjacent cell Ca1 in the direction opposite to the sweep direction instead of the speed data of the adjacent cell Ca1. Also, in the judgment process, the data processing unit 17 may use the average value of the Doppler velocities indicated by the speed data of a predetermined number of cells C adjacent to the cell of interest Ct in the direction opposite to the sweep direction instead of the Doppler velocity indicated by the speed data of the adjacent cell Ca1.

[0046] In addition, in the determination process, the data processing unit 17 may use the speed data of a cell C adjacent to the neighboring cell Cb1 in the transmission direction of the radar wave, instead of the speed data of the neighboring cell Cb1. In addition, in the determination process, the data processing unit 17 may use the average value of the Doppler velocities indicated by the speed data of a predetermined number of cells C adjacent to the cell of interest Ct in the transmission direction of the radar wave, instead of the Doppler velocity indicated by the speed data of the neighboring cell Cb1.

[0047] The data processing unit 17 performs a determination process and a correction process each time the speed data of one cell C is stored in the memory unit 16 by the speed data generating unit 15B. More specifically, when the speed data of the cell C in the mth row and nth column is stored in the memory unit 16 by the speed data generating unit 15B, the data processing unit 17 determines whether or not the cell C in the (m-1)th row and nth column corresponds to a boundary cell Cx based on the speed data of the cell C in the mth row and nth column, the speed data of the cell C in the (m-1)th row and nth column in the memory unit 16, and the speed data of the cell C in the (m-1)th row and (n-1)th column in the memory unit 16. Here, n and m are integers of 2 or more. The first row is the row closest to the ship 1.

[0048] When the data processing unit 17 completes the determination process and correction process for one cell C, it outputs the amplitude data of the cell C after the correction process to the display processing unit 18. When the data processing unit 17 completes the determination process and correction process for the cell C in the n-th column, it deletes the amplitude data and speed data of the cell C in the (n-1)th column from the storage unit 16. Then, the data processing unit 17 waits for the speed data of the cell C belonging to the (n+1)th column to be stored in the storage unit 16 by the speed data generating unit 15B. Note that the data processing unit 17 may be configured to perform the determination process and correction process every time the speed data of one cell C is stored in the storage unit 16 by the speed data generating unit 15B, and output the amplitude data of the cell C in one column after the correction process to the display processing unit 18 after the determination process and correction process for the cells C in one column are completed.

[0049] The display processing unit 18 receives the amplitude data from the data processing unit 17, generates an echo image based on the received amplitude data, and performs processing to display the generated echo image on a display device (not shown). More specifically, the display processing unit 18 updates the echo image displayed on the display device based on the received amplitude data every time it receives amplitude data for one column of cells C from the data processing unit 17. In this way, by displaying the echo image generated based on the amplitude data after the correction processing, it is possible to display multiple nearby targets S separately.

[0050] FIG. 6 is a diagram showing an example of the judgment process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. The thick frame in FIG. 6 indicates a reference pattern Pn1 showing the positional relationship between the cell of interest Ct in the judgment process and the adjacent cells Ca1 and Cb1 referred to in the judgment process. FIG. 6 shows some cells C corresponding to the boundary part of the targets S1 and S2 among the multiple cells C corresponding to the detection target area Ta when the targets S1 and S2 are close to each other as shown in FIG. 2. The dashed line in FIG. 6 indicates the boundary BD between the actual targets S1 and S2 when an echo image is displayed based on the amplitude data of each cell C. The hatched cells C in FIG. 6 indicate the cells C that are determined by the data processing unit 17 to be the boundary cell Cx in the judgment process and whose amplitude data is corrected to zero in the correction process.

[0051] 6, the data processing unit 17 performs a determination process and a correction process to determine that the cell C near the boundary BD is a boundary cell Cx, and corrects the amplitude indicated by the amplitude data of the boundary cell Cx to 0. This allows the user of the radar device 101 to distinguish and recognize the targets S1 and S2 in the echo image displayed based on the amplitude data after the correction process.

[0052] FIG. 7 is a diagram showing an example of the determination process and correction process by the radar device according to the comparative example. The thick frame in FIG. 7 indicates a reference pattern PnC showing the positional relationship between the cell of interest Ct and the adjacent cells Cr1 and Cr2 in the process of the radar device according to the comparative example. FIG. 7 shows some cells C corresponding to the boundary part of the targets S1 and S2 as in FIG. 6. The hatched cells C in FIG. 7 indicate the cells C whose amplitude data indicates has been reduced to zero by the radar device described in the cited document 1. The radar device described in the cited document 1 performs a process of reducing the amplitude indicated by the amplitude data of the cell of interest Ct to zero when the difference between the Doppler velocities corresponding to the two adjacent cells Cr1 adjacent to each other in the azimuth direction across the cell of interest Ct is equal to or greater than a predetermined value, or when the difference between the Doppler velocities corresponding to the two adjacent cells Cr2 adjacent to each other in the distance direction across the cell of interest Ct is equal to or greater than a predetermined value.

[0053] 7, the radar device described in the cited document 1 can reduce the amplitude indicated by the amplitude data of the cells C near the boundary BD to zero. However, the radar device described in the cited document 1 needs to use Doppler velocities corresponding to three rows of cells C, and therefore needs to store the amplitude data and velocity data of at least three rows of cells C in the memory unit 16.

[0054] Furthermore, the radar device described in the cited document 1 reduces to zero the amplitude indicated by the amplitude data of the leading edge cell Cf, which is the cell C of the leading edge of the target S1 on the ship 1 side in the distance direction. Therefore, in an echo image displayed based on the processed amplitude data, a user perceives that the ship-side boundary of the target S1 is located farther from the ship than it actually is by the amount of the leading edge cell Cf. Furthermore, when the distance between the ship and the target S1 is calculated based on the processed amplitude data, the distance between the ship and the target S is calculated to be a value larger than the actual distance by the amount of the leading edge cell Cf.

[0055] In contrast, in the radar device 101 according to the embodiment of the present invention, the data processing unit 17 performs the judgment process using the speed data of two columns of cells C, and deletes the amplitude data and speed data of the past column of cells C from the memory unit 16 each time the judgment process is performed, so that the amplitude data and speed data of two columns of cells C can be stored in the memory unit 16.

[0056] 6, in the judgment process, the data processing unit 17 does not judge the leading edge cell Cf as the boundary cell Cx, but judges the cell at the trailing edge of the target S2 located in front of the ship 1 as the boundary cell Cx. Therefore, the user can more correctly recognize the ship-side boundary of the target S1 in the echo image displayed by the display processing unit 18. Also, the distance between the ship and the target S1 can be more accurately calculated based on the amplitude data after the correction process.

[0057] (Another example of the target boundary BD) 8 to 11 are diagrams illustrating other examples of the determination process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention.

[0058] Fig. 8 shows some of the cells C corresponding to the boundary between the targets S3 and S4 among the multiple cells C corresponding to the detection area Ta when the targets S3 and S4 are close to each other. The dashed line in Fig. 8 shows the boundary BD between the actual targets S3 and S4 when an echo image is displayed based on the amplitude data for each cell C.

[0059] Fig. 9 shows some of the cells C corresponding to the boundary between the targets S5 and S6 among the multiple cells C corresponding to the detection area Ta when the targets S5 and S6 are close to each other. The dashed line in Fig. 9 shows the boundary BD between the actual targets S5 and S6 when an echo image is displayed based on the amplitude data for each cell C.

[0060] Fig. 10 shows a part of cells C corresponding to the boundary between targets S7 and S8 among a plurality of cells C corresponding to a detection target area Ta when targets S7 and S8 are close to each other. The dashed line in Fig. 10 shows the boundary BD between the actual targets S7 and S8 when an echo image is displayed based on the amplitude data for each cell C.

[0061] Fig. 11 shows some of the cells C corresponding to the boundary portion of the target S9 on the ship 1 side among the multiple cells C corresponding to the detection target area Ta. Referring to Fig. 11, the speed data of the cell Cv adjacent to the leading edge cell Cf of the target S9 in the radar transmission direction may contain noise and may not be stable.

[0062] 8 to 10, in the arrangement of the targets S3 and S4, the data processing unit 17 judges the leading edge cell Cf of the target S4 as the boundary cell Cx. However, in the arrangement of the targets S5 and S6 and the arrangement of the targets S7 and S8, the data processing unit 17 does not judge the leading edge cell Cf of the targets S5 and S7 as the boundary cell Cx, but judges the trailing edge cell C of the targets S6 and S8 located in front of the ship 1 as the boundary cell Cx. Therefore, in the echo image displayed by the display processing unit 18, the ship-side boundary of the targets S5 and S7 can be more accurately recognized. In addition, the distance between the ship and the targets S5 and S7 can be more accurately calculated based on the amplitude data after the correction process.

[0063] Also, referring to Figure 11, when the difference between the Doppler velocity indicated by the velocity data of the leading edge cell Cf of the target S9 and the Doppler velocity indicated by the velocity data of cell Cv is greater than or equal to a predetermined value, the data processing unit 17 may mistakenly determine that the leading edge cell Cf of the target S9 is a boundary cell Cx.

[0064] 12 to 15 are diagrams illustrating other examples of the determination process and the correction process by the data processing unit in the radar device according to the comparative example.

[0065] Fig. 12 shows some of the cells C corresponding to the boundary between targets S3 and S4, similar to Fig. 8. Fig. 13 shows some of the cells C corresponding to the boundary between targets S5 and S6, similar to Fig. 9. Fig. 14 shows some of the cells C corresponding to the boundary between targets S7 and S8, similar to Fig. 10. Fig. 15 shows some of the cells C corresponding to the boundary on the ship 1 side of target S9, similar to Fig. 11.

[0066] With reference to Figures 12 to 14, the radar device described in Cited Document 1 does not perform processing to reduce the amplitude indicated by the amplitude data of the leading edge cell Cf of targets S4 and S7 to zero, but does perform processing to reduce the amplitude indicated by the amplitude data of the leading edge cell Cf of target S5 to zero.

[0067] 15, the radar device described in the cited document 1 does not perform a process to reduce the amplitude indicated by the amplitude data of the leading edge cell Cf to zero when the difference between the Doppler velocity indicated by the velocity data of the cell Cv of the target S9 is equal to or greater than a predetermined value, but performs a process to reduce the amplitude indicated by the amplitude data of the cell Cv to zero. This may result in the target S9 being split into two in the echo image, or may cause problems in processing using the amplitude data in a subsequent unit.

[0068] (Another example of decision processing 1) 16 is a diagram for explaining another example of the determination process by the data processor in the radar device according to the embodiment of the present invention. Referring to FIG. 16, in the determination process, the data processor 17 may use the speed data of the neighboring cell Ca2, which is the cell C adjacent to the cell of interest Ct in the sweep direction, instead of the neighboring cell Ca1.

[0069] More specifically, the data processor 17 compares the speed data of the cell of interest Ct with that of the adjacent cell Ca2, and compares the speed data of the cell of interest Ct with that of the adjacent cell Cb1. If the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and that indicated by the speed data of the adjacent cell Ca2 is equal to or greater than a predetermined value, or if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and that indicated by the speed data of the adjacent cell Cb1 is equal to or greater than a predetermined value, the data processor 17 determines that the cell of interest Ct corresponds to the boundary cell Cx.

[0070] 17 to 20 are diagrams showing an example of the judgment process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. The thick frame in each of FIGS. 17 to 20 shows a reference pattern Pn2 showing the positional relationship between the cell of interest Ct in the judgment process and the adjacent cells Ca2 and Cb1 referred to in the judgment process. FIG. 17 shows some cells C corresponding to the boundary part of the targets S1 and S2 as in FIG. 6. FIG. 18 shows some cells C corresponding to the boundary part of the targets S3 and S4 as in FIG. 8. FIG. 19 shows some cells C corresponding to the boundary part of the targets S5 and S6 as in FIG. 9. FIG. 20 shows some cells C corresponding to the boundary part of the targets S7 and S8 as in FIG. 10.

[0071] 17 to 20, when the data processing unit 17 uses the speed data of the adjacent cell Ca2 instead of the adjacent cell Ca1, it judges the leading edge cell Cf of the targets S1 and S5 as the boundary cell Cx in the arrangement of the targets S1 and S2 and the arrangement of the targets S5 and S6. However, when the data processing unit 17 uses the speed data of the adjacent cell Ca2 instead of the adjacent cell Ca1, it does not judge the leading edge cell Cf of the targets S4 and S7 as the boundary cell Cx in the arrangement of the targets S3 and S4 and the arrangement of the targets S7 and S8, but judges the trailing edge cell C of the targets S3 and S8 located in front of the ship 1 as the boundary cell Cx. Therefore, in the echo image displayed by the display processing unit 18, the ship-side boundary of the targets S4 and S7 can be more correctly recognized.

[0072] (Another example of judgment processing 2) Fig. 21 is a diagram for explaining another example of the determination process by the data processor in the radar device according to the embodiment of the present invention. Referring to Fig. 21, in the determination process, the data processor 17 may use the speed data of the neighboring cell Cb2, which is the cell C adjacent to the cell of interest Ct in the opposite direction to the transmission direction of the radar wave, instead of the neighboring cell Cb1.

[0073] More specifically, the data processing unit 17 compares the speed data of the cell of interest Ct with that of the adjacent cell Ca1, and compares the speed data of the cell of interest Ct with that of the adjacent cell Cb2. If the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and that indicated by the speed data of the adjacent cell Ca1 is equal to or greater than a predetermined value, or if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and that indicated by the speed data of the adjacent cell Cb2 is equal to or greater than a predetermined value, the data processing unit 17 determines that the cell of interest Ct corresponds to the boundary cell Cx.

[0074] 22 to 26 are diagrams showing an example of the judgment process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. The thick frame in FIG. 22 to FIG. 26 shows a reference pattern Pn3 showing the positional relationship between the cell of interest Ct in the judgment process and the adjacent cells Ca1 and Cb2 referred to in the judgment process. FIG. 22 shows some cells C corresponding to the boundary part of the targets S1 and S2 as in FIG. 6. FIG. 23 shows some cells C corresponding to the boundary part of the targets S3 and S4 as in FIG. 8. FIG. 24 shows some cells C corresponding to the boundary part of the targets S5 and S6 as in FIG. 9. FIG. 25 shows some cells C corresponding to the boundary part of the targets S7 and S8 as in FIG. 10. FIG. 26 shows some cells C corresponding to the boundary part on the ship 1 side of the target S9 as in FIG. 11.

[0075] 22 to 26, when the data processing unit 17 uses the speed data of the adjacent cell Cb2 instead of the adjacent cell Cb1, it judges the leading edge cell Cf of the targets S4, S5, and S7 as the boundary cell Cx in the arrangement of the targets S3 and S4, the arrangement of the targets S5 and S6, and the arrangement of the targets S7 and S8. When the data processing unit 17 uses the speed data of the adjacent cell Cb2 instead of the adjacent cell Cb1, it judges the cell Cv as the boundary cell Cx if the difference between the Doppler velocity indicated by the speed data of the leading edge cell Cf of the target S9 and the Doppler velocity indicated by the speed data of the cell Cv is equal to or greater than a predetermined value. This may cause the target S9 to be split into two in the echo image or cause a problem in processing using the amplitude data in a subsequent unit. However, when the data processing unit 17 uses the speed data of the adjacent cell Cb2 instead of the adjacent cell Cb1, in the arrangement of the targets S1 and S2, it does not determine the leading edge cell Cf of the target S1 as the boundary cell Cx, but determines the trailing edge cell C of the target S2, which is located in front as seen from the ship 1, as the boundary cell Cx. Therefore, in the echo image displayed by the display processing unit 18, the boundary of the target S2 on the ship side can be more correctly recognized.

[0076] (Another example of judgment processing 3) 27 is a diagram for explaining another example of the determination process by the data processor in the radar device according to the embodiment of the present invention. Referring to FIG. 27, the data processor 17 may use the speed data of the neighboring cells Ca2 and Cb2 instead of the speed data of the neighboring cells Ca1 and Cb1 in the determination process.

[0077] More specifically, the data processor 17 compares the speed data of the cell of interest Ct with that of the adjacent cell Ca2, and compares the speed data of the cell of interest Ct with that of the adjacent cell Cb2. If the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and that indicated by the speed data of the adjacent cell Ca2 is equal to or greater than a predetermined value, or if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and that indicated by the speed data of the adjacent cell Cb2 is equal to or greater than a predetermined value, the data processor 17 determines that the cell of interest Ct corresponds to the boundary cell Cx.

[0078] 28 to 31 are diagrams showing an example of the judgment process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. The thick frame in FIG. 28 to FIG. 31 shows a reference pattern Pn4 indicating the positional relationship between the cell of interest Ct in the judgment process and the adjacent cells Ca2 and Cb2 referred to in the judgment process. It is a diagram showing an example of the judgment process and the correction process by the data processing unit in the radar device according to the embodiment of the present invention. FIG. 28 shows a part of the cells C corresponding to the boundary part of the targets S1 and S2 as in FIG. 6. FIG. 29 shows a part of the cells C corresponding to the boundary part of the targets S3 and S4 as in FIG. 8. FIG. 30 shows a part of the cells C corresponding to the boundary part of the targets S5 and S6 as in FIG. 9. FIG. 31 shows a part of the cells C corresponding to the boundary part of the targets S7 and S8 as in FIG. 10.

[0079] 28 to 31, when the data processing unit 17 uses the speed data of the adjacent cells Ca2 and Cb2 instead of the adjacent cells Ca1 and Cb1, it judges the leading edge cell Cf of the targets S1, S5, and S7 as the boundary cell Cx in the arrangement of the targets S1 and S2, the arrangement of the targets S5 and S6, and the targets S7 and S8. However, when the data processing unit 17 uses the speed data of the adjacent cells Ca2 and Cb2 instead of the adjacent cells Ca1 and Cb1, it does not judge the leading edge cell Cf of the target S4 as the boundary cell Cx in the arrangement of the targets S3 and S4, but judges the cell C of the trailing edge of the target S3 located in front as seen from the ship 1 as the boundary cell Cx. Therefore, the boundary of the target S4 on the ship side can be more correctly recognized in the echo image displayed by the display processing unit 18.

[0080] (Comparison of reference patterns used in decision processing) Fig. 32 is a diagram showing the superiority or inferiority of adjacent cells used in the judgment process by the data processing unit in the radar device according to the embodiment of the present invention. In Fig. 32, "OK" indicates a case where the cell C at the trailing edge of the target S located in front of the ship 1 is judged to be a boundary cell Cx, and the amplitude indicated by the amplitude data of the trailing edge cell C is reduced to zero. In Fig. 32, "NG" indicates a case where the leading edge cell Cf is judged to be a boundary cell Cx, and the amplitude indicated by the amplitude data of the leading edge cell Cf is reduced to zero.

[0081] 32, from the results of the determination process in four variations of the arrangement of two adjacent targets S, it is understood that it is preferable to use the adjacent cells Ca1 and Cb1 in the determination process.

[0082] Furthermore, when the data processing unit 17 uses the adjacent cell Ca2 instead of the adjacent cell Ca1 in the judgment process, each time the speed data of the cell C in the nth column is stored in the memory unit 16 by the speed data generating unit 15B, it is necessary to judge whether or not the cell C in the (n-1)th column corresponds to a boundary cell Cx based on the speed data of the cell C in the nth column and the speed data of the cell C in the (n-1)th column in the memory unit 16. This may complicate the judgment process and correction process or cause a delay in the display of the echo image.

[0083] [Operation flow] The radar device according to the embodiment of the present invention includes a computer including a memory, and a processor such as a CPU in the computer reads out from the memory a program including some or all of the steps of the following flowcharts and executes it. The program of this device can be installed from the outside. The program of this device is distributed in a state stored on a recording medium or via a communication line.

[0084] 33 is a flowchart showing an example of an operation performed by the radar device according to the embodiment of the present invention to display an echo image. For example, the radar device 101 executes the process shown in the flowchart of FIG. 33 for each sweep period T.

[0085] Referring to FIG. 33, first, the radar device 101 transmits radar waves (step S11).

[0086] Next, the radar device 101 receives a reflected wave that is the radar wave reflected by the target S (step S12).

[0087] Next, the radar device 101 generates amplitude data and speed data for each row of cells C based on the received reflected waves, and stores the generated amplitude data and speed data for cells C in a storage unit (step S13).

[0088] Next, the radar device 101 sets a cell of interest Ct (step S14).

[0089] Next, the radar device 101 performs a determination process to determine whether or not the cell of interest Ct corresponds to a boundary cell Cx (step S15).

[0090] Next, the radar device 101 performs a correction process to correct the amplitude indicated by the amplitude data of the cell of interest Ct determined to be the boundary cell Cx to zero (step S16).

[0091] Next, the radar device 101 repeats the processes from step S14 to step S16 until the judgment process and correction process for all cells C in one column are completed (NO in step S17). When the judgment process and correction process for all cells C in one column are completed (YES in step S17), the radar device 101 generates an echo image based on the amplitude data of the cells C in one column after the correction process, and performs a process of displaying the generated echo image on a display device not shown (step S18).

[0092] 34 is a flowchart showing an example of an operation when the radar device according to the embodiment of the present invention performs a determination process, showing details of step S15 in FIG.

[0093] 34, first, the radar device 101 compares the speed data of the cell of interest Ct with the speed data of the adjacent cells Ca1 and Cb1 (step S21).

[0094] Next, if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Ca1 is greater than or equal to a predetermined value, or if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Cb1 is greater than or equal to a predetermined value (YES in step S22 or YES in step S23), the radar device 101 determines that the cell of interest Ct corresponds to the boundary cell Cx (step S24).

[0095] On the other hand, if the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Ca1 is less than a predetermined value, and the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Cb1 is less than a predetermined value (NO in step S22 and NO in step S23), the radar device 101 determines that the cell of interest Ct does not correspond to the boundary cell Cx (step S25).

[0096] In the radar device 101 according to the embodiment of the present invention, the data processing unit 17 is configured to determine whether or not the cell of interest Ct corresponds to the boundary cell Cx based on the result of comparing the speed data of the cell of interest Ct with the speed data of the adjacent cells Ca1 and Cb1 in the determination process, but the present invention is not limited to this. The data processing unit 17 may be configured to determine whether or not the cell of interest Ct corresponds to the boundary cell Cx based on the result of comparing the amplitude indicated by the amplitude data of the cell of interest Ct with a predetermined threshold. Specifically, the data processing unit 17 determines that the cell of interest Ct corresponds to the boundary cell Cx when the amplitude indicated by the amplitude data of the cell of interest Ct is equal to or greater than a predetermined threshold, and the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Ca1 is equal to or greater than a predetermined value, or when the absolute value of the difference between the Doppler velocity indicated by the speed data of the cell of interest Ct and the Doppler velocity indicated by the speed data of the adjacent cell Cb1 is equal to or greater than a predetermined value. On the other hand, if the amplitude indicated by the amplitude data of the target cell Ct is less than the threshold value, the data processing unit 17 determines that the target cell Ct does not correspond to the boundary cell Cx, regardless of the comparison result between the speed data of the target cell Ct and the speed data of the adjacent cells Ca1 and Cb1.

[0097] Furthermore, in the radar device 101 according to the embodiment of the present invention, the generating unit 15 may be configured to include an acceleration data generating unit instead of or in addition to the speed data generating unit 15B. The acceleration data generating unit generates acceleration data indicating the acceleration of the target S at a position corresponding to the cell C based on the reception data received from the receiving unit 14. The acceleration data is an example of displacement data. In this case, in the determination process, the data processing unit 17 determines whether or not the target cell Ct corresponds to the boundary cell Cx based on the comparison result between the acceleration data of the target cell Ct and the acceleration data of the cell C adjacent to the target cell Ct in the azimuth direction and the comparison result between the acceleration data of the target cell Ct and the acceleration data of the cell C adjacent to the target cell Ct in the distance direction.

[0098] The above-described embodiments should be considered as illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0099] 1 ship 11 Antenna 12 Switching section 13 Transmitter 14 Receiving section 15 Generation part 15A Amplitude data generator 15B Speed ​​data generator 16 Memory section 17 Data Processing Section 18 Display processing section 101 Radar Equipment Ta Detection area S1,S2,S3,S4,S5,S6,S7,S8,S9 Target C, Cv Cell Ct Cell of interest Ca1, Ca2, Cb1, Cb2, Cr1, Cr2 adjacent cells Cf leading edge cell Pn1, Pn2, Pn3, Pn4, PnC reference patterns BD boundary

Claims

1. A transmitter that transmits radar waves; a receiving unit that receives a reflected wave of the radar wave reflected by a target; a generating unit that generates, based on the reflected wave, amplitude data of the reflected wave and displacement data indicating a velocity or an acceleration of the target for each cell on a coordinate system having an azimuth direction and a distance direction as coordinate axes; a judgment unit that performs a judgment process to judge whether the cell of interest is a boundary cell, which is a cell that serves as a boundary separating different targets, based on a comparison result between the displacement data of a cell of interest among the plurality of cells and the displacement data of a cell adjacent to the cell of interest in the azimuth direction or the distance direction.

2. 2. The radar device according to claim 1, wherein, in the determination process, the determination unit determines whether the target cell corresponds to the boundary cell based on a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the azimuth direction, and a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the distance direction.

3. 3. The radar device according to claim 2, wherein, in the determination process, the determination unit determines that the target cell corresponds to the boundary cell if an absolute value of a difference between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the azimuth direction is equal to or greater than a predetermined value, and an absolute value of a difference between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the distance direction is equal to or greater than a predetermined value.

4. the transmitter repeatedly transmits the radar wave while changing a transmission direction of the radar wave along a first direction among the azimuth directions; 4. The radar device according to claim 1, wherein the determination unit, in the determination process, determines whether the target cell corresponds to the boundary cell based on a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in a direction opposite to the first direction.

5. the determination unit performs the determination process while changing the cell to be set as the target cell along a second direction of the distance directions; 5. The radar device according to claim 4, wherein the determination unit, in the determination process, determines whether the target cell corresponds to the boundary cell based on a comparison result between the displacement data of the target cell and the displacement data of the cell adjacent to the target cell in the second direction.

6. The radar device further comprises: The radar device according to claim 1 , further comprising a reduction processing unit that reduces an amplitude indicated by the amplitude data of the cell of interest that has been determined to correspond to the boundary cell.

7. A data processing method in a radar device, comprising: Transmitting radar waves, receiving a reflected wave of the radar wave reflected by a target; generating amplitude data of the reflected wave and displacement data indicating a velocity or an acceleration of the target for each cell on a coordinate system having a azimuth direction and a distance direction as coordinate axes based on the reflected wave; A data processing method that performs a judgment process to determine whether the target cell is a boundary cell, which is a cell that serves as a boundary separating different targets, based on a comparison result between the displacement data of a target cell among a plurality of the cells and the displacement data of a cell adjacent to the target cell in the azimuth direction or the distance direction.

8. A data processing program for use in a radar device, A process of transmitting radar waves; A process of receiving a reflected wave of the radar wave reflected by a target; generating amplitude data of the reflected wave and displacement data indicating a velocity or an acceleration of the target for each cell on a coordinate system having a direction and a distance as coordinate axes based on the reflected wave; A data processing program for causing a computer to execute a process of performing a judgment process for determining whether or not the target cell is a boundary cell, which is a cell that serves as a boundary separating different targets, based on a comparison result between the displacement data of a target cell among the plurality of cells and the displacement data of a cell adjacent to the target cell in the azimuth direction or the distance direction.

Images