JPH04212082A - Radar equipment - Google Patents

Abstract

PURPOSE:To properly display the moving locus of an object to be detected such as an island or another ship in such a case that the bow line of one's own ship is always changed. CONSTITUTION:A moving locus signal (showing the moving locus of an object to be detected such as an island or another ship) is formed on the basis of the output signal (present data) of a buffer memory 3 and the output signal (past data) from a moving locus signal processing memory 8a (first memory) in a moving locus signal forming part 4a (signal processing means) but the moving locus signal processing memory 8a stores the moving locus of the object to be detected in a memory element having an address determined based on a predetermined azimuth regardless of the course of one's own ship in any indicated display mode and, therefore, the data stored in the buffer memory 3 and the moving locus signal processing memory 8a is allowed to correspond and the moving locus of the object to be detected is properly displayed.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention receives echo signals returning from each direction by sequentially emitting radar detection signals in different directions while rotating an antenna, and once writes these echo signals into an image memory. It relates to a radar device that stores the information, then reads it out and supplies it to a display, and displays the surrounding situation of the radar antenna on the display screen, and in particular,
This invention relates to a device that can accurately display the movement trajectory of objects to be detected, such as islands or other ships.

0002

2. Description of the Related Art A conventional radar device will be explained with reference to FIG. That is, the receiver 1 receives and detects and amplifies one beam of echo signals returning from each direction due to detection pulse signals sequentially emitted in different directions as a radar antenna (not shown) rotates. The one-beam reception signal from the receiver 1 is A/D converted by an A/D converter 2 and temporarily stored in a buffer memory 3 in time series. The received signal (echo data) supplied from this buffer memory 3 is
The write data creation unit 4 converts the data into image display data.

Output data from the write data generating section 4 is written into the frame memory 6 at a write address generated by a write address generating section 5. The data written in the frame memory 6 is read out based on the read address generated by the read address generation section 7 according to the raster scan method. The read data is displayed as an image on a display device such as a CRT (not shown).

The write address generator 5 generates a write address consisting of orthogonal coordinates (X, Y) based on the antenna direction, the course of the own ship, the designated display mode, etc., and performs polar coordinate-orthogonal coordinate conversion. conduct. This conversion is performed based on the following equation.

[0005]
θG −θC. ) Xc, Yc are own ship position addresses on frame memory, R
is the distance from the own ship's position, θ is the angle in the sweep direction from the Y axis (frame memory), θA is the antenna angle with the bow direction as a reference, θG is the own ship's course, and θC is the set course.

[0006] In the above-mentioned radar device, when the readout for display on the display device is performed using the raster scan method, the write address generator 5 is configured to perform coordinate conversion from polar coordinates to rectangular coordinates. When using the scan method, there is no need to perform the above-mentioned coordinate transformation in the write address generation section 5.

In the conventional radar device described above, the mode setting section (not shown) sets the north-up mode (
(hereinafter abbreviated as NU mode), heads-up mode (
(hereinafter abbreviated as HU mode), course up mode (
You can select from three display modes (hereinafter abbreviated as CU mode).

■ In the NU mode, as shown in FIG.
Directly above the display screen always points north. In this case, images of fixed targets such as fixed buoys are always displayed in the fixed position regardless of the direction of the ship's bow, but if the ship's bow is facing north, the ship's bow line will be at the position indicated by the solid arrow; When you change direction to the east, the bow lines will be displayed at the positions indicated by the dashed arrows.

■ In the HU mode, as shown in FIG.
The point directly above the display screen always points to the bow. In this case, the bow line is always displayed pointing directly above the display screen regardless of the bow direction, but if the bow direction is set to north, fixed images such as fixed buoys will be at the A1 position, and the bow direction will be When changing to the east, the fixed image is displayed at the A2 position.

■ In the CU mode, as shown in FIG.
The line immediately above the display screen always indicates the preset scheduled course of the ship. In this case, images of fixed targets such as fixed buoys are always displayed in the fixed position regardless of the direction of the ship's bow, but if the ship's bow is facing north, the ship's bow line will be at the position indicated by the imaginary line, and When you change direction to the east, the bow lines will be displayed at the positions indicated by the dashed arrows.

As described above, in the NU mode and the CU mode, a fixed target is displayed at a fixed position on the display screen, and the bow line is displayed at a different position on the display screen depending on the direction.
Furthermore, in the HU mode, the bow line is displayed at a fixed position on the display screen, and fixed targets are displayed at different positions on the display screen depending on the direction of the bow. Note that the HU mode is relatively frequently used because the actual scenery seen by the operator matches the display screen.

By the way, it is desired to display the movement trajectory of objects to be detected, such as islands and other ships, due to requests such as wanting to know when other ships are approaching while one's own ship is stopped. To display the movement trajectory of such a detected object, for example,
Frame memory 6 stores the current received signal and past received signals.
This can be done by writing data over and over again and giving that data to the display. In order to perform such processing in the conventional radar device, the signal from the buffer memory 3 is used as the current signal, the signal from the frame memory 6 is used as the past signal, and the write data creation unit 4 processes the signal. It is conceivable to write the processed signal into the frame memory 6 again.

[0013]

[Problem to be solved by the invention] By the way, the process of displaying the movement trajectory of objects to be detected, such as islands and other ships,
the current echo signal given from the buffer memory 3;
Although this is possible in the NU mode and CU mode because it uses past echo signals that have already been written into the frame memory 6, in the frequently used HU mode, the movement of the detected object is It is impossible to properly display the trajectory.

[0014] In other words, in the conventional radar device described above, among the display modes on the display unit, in the NU mode and CU mode, for example, when displaying when the own ship is stopped,
Even if the bow direction of the ship changes constantly and the data written in the frame memory 6 for one rotation of the antenna is updated moment by moment, the data indicating a fixed target is always stored in the frame memory 6.
Since it is written in the same position above, the display position of the fixed target remains unchanged on the screen. However, in HU mode, if the ship's bow direction changes constantly when the own ship is stopped, for example, when writing the echo signal captured by the antenna to the frame memory 6, even if the data indicating a fixed target is Since data is written to a different storage element on the frame memory 6 every time the antenna rotates, the display position of the fixed target changes from moment to moment on the screen.

[0015] In this way, in the HU mode, when updating write data to the frame memory from time to time,
Since the course is taken into consideration, it is not possible to write the current signal and past signal in correspondence with each other at the same position. therefore,
In the HU mode, it was not possible to properly display the movement trajectory of the detected object or perform scan correlation processing.

[0016] The present invention was devised in view of the above circumstances, and its main purpose is to properly display the movement trajectory of the object to be detected, regardless of the display mode, when the bow line of the own ship is constantly changing. The goal is to be able to display

Another object of the present invention is to enable proper display of the movement trajectory of the object to be detected regardless of the display mode when the bow line of the own ship is constantly changing, and to perform scan correlation processing. The goal is to ensure that it is executed correctly.

[0018]

[Means for Solving the Problems] In order to achieve the above-mentioned problems, the present invention sequentially emits detection signals in different directions, receives the returning echo signals, and shows the surroundings in a wide range of directions on a display. The radar device that displays the situation has the following configuration.

A first radar device of the present invention (corresponding to claim 1) includes a receiving section that receives an echo signal, a buffer memory that temporarily stores an echo signal caused by a detection signal sent from the receiving section, A first memory that stores signals given from the signal processing means described below at address positions determined based on a predetermined direction, and a current echo signal output from the buffer memory and a past echo signal read from the first memory. a signal processing means for providing a movement trajectory signal obtained by signal processing (a signal representing the movement trajectory of an object to be detected such as an island or another ship) to a first memory and a second memory; and a movement trajectory output from the signal processing means. A second memory that stores the signals at address positions determined by the set display mode.
The present invention is characterized in that it includes a memory and a display that displays the signal read from the second memory.

A second radar device of the present invention (corresponding to claim 2) comprises: a receiving section that receives an echo signal; a buffer memory that temporarily stores the echo signal caused by the detection signal sent from the receiving section; A first memory that stores signals given from the signal processing means described below at address positions determined with reference to a predetermined azimuth, and a current echo signal output from the buffer memory and a past echo signal read from the first memory. A signal processing means for providing a movement trajectory signal (representing the movement trajectory of an object to be detected such as an island or another ship) obtained by signal processing to a first memory and a second memory, and output from the signal processing means and correlation means. Output from a second memory that stores signals at address positions determined by a set display mode, a third memory that stores signals given from the correlation means described below at address positions determined based on a predetermined direction, and a buffer memory. correlation means for correlating and correlating the current echo signal read out from the echo signal and the past echo signal read out from the third memory, and providing the output signal to the third memory and the second memory; and the signal read out from the second memory. It is characterized in that it is equipped with a display device that displays.

[0021]

[Operation] In the first radar device of the present invention, since the signal output from the signal processing means is stored in the first memory at an address determined in a predetermined direction, for example, with north as a reference, it is not affected by the turning of the own ship. First, the current echo signal output from the buffer memory and the past echo signal output from the first memory will correspond. Further, when an object to be detected such as an island or another ship moves, the output signal of the signal processing means is written to different storage elements of the first and second memories. Therefore, if the signal processing means processes both of the signals, a movement trajectory signal that properly represents the movement trajectory of the object to be detected can be obtained.

The signal output from this signal processing means is
Since the signal is written in the second memory to the storage element corresponding to the address determined by the designated display mode, the signal output from the second memory is displayed on the display in the designated display mode.

[0023] In the second radar device of the present invention, the first
In addition to the functions of the radar device (displaying the movement trajectory of detected objects such as islands and other ships), the following functions (scan correlation processing)
I do.

That is, since the signal output from the correlation means is stored in the third memory in a predetermined direction, for example, at an address determined with reference to north, the current signal output from the buffer memory is not affected by the turning of the own ship. The echo signal and the past echo signal output from the third memory are written into a storage element having a corresponding address. Therefore,
Even if data representing a fixed target exists in the past signal from the third memory, if data corresponding to data representing the fixed target does not exist in the current signal from the buffer memory, the third memory The data representing fixed targets in the 3 memory is considered to be unnecessary waves due to reflection from the sea surface, etc. Therefore, by correlating both output signals with the correlation means, it becomes possible to obtain data of only the necessary reflected waves from which data of unnecessary waves has been removed.

Furthermore, since the signal output from the correlation means is written to a storage element in the second memory having an address determined by the specified display mode, the signal output from this second memory is written to the storage element having the address determined by the specified display mode. Displayed in display mode. If the display mode is specified as HU mode, data will be written to the storage element determined by NU mode for the third memory, and HU mode will be written to the second memory.
Data is written to a storage element having a write address determined by the mode. Therefore, if the scan correlation process is performed using the past data written to the third memory and the current data given from the buffer memory, the scan correlation process can be performed correctly even in the HU mode.

[0026]

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an embodiment of the present invention. In FIG. 1, the same reference numerals as those shown in FIG. 8 of the conventional example refer to the same parts, portions, etc.

The movement trajectory signal generation unit 4a converts the echo signal output from the buffer memory 3 into image display data and provides it to the frame memory 6 and the movement trajectory signal processing memory 8a. Based on the output signal and the output signal from the movement trajectory signal processing memory 8a, for example, if a movement trajectory signal that lasts only for a predetermined period of time is displayed, or if the movement trajectory is displayed, the movement trajectory portion indicating the current position of the ship may be brightest. A movement trajectory signal (a signal representing the movement trajectory of an object to be detected, such as an island or another ship) is generated by signal processing so that older parts of the movement trajectory are displayed darker.

The movement trajectory signal processing memory 8a always outputs the movement trajectory signal given from the movement trajectory signal generation unit 4a to the second write address, regardless of which of the NU mode, HU mode, and CU mode is specified as the usage mode. Generating part 9
The data is written to a memory element having a write address determined by, for example, NU mode. On the other hand, the frame memory 6 stores the movement trajectory signal given from the movement trajectory signal generation section 4a in a specified display mode (NU mode, HU mode, C mode) given from the first write address generation section 5.
The data is written to a memory element having a write address determined by U mode). The data written in the frame memory 6 is read out based on the read address generated by the read address generation section 7 according to the raster scan method. The read data is displayed as an image on a display device such as a CRT (not shown).

In this way, the movement trajectory signal processing memory 8a
The write address for is always the write address determined by, for example, NU mode, regardless of the specified display mode, so the correspondence between the past signal from the movement trajectory signal processing memory 8a and the current signal from the buffer memory 3 is maintained. You will be able to get it accurately. Therefore, even if the HU mode is specified, the movement trajectory signal generation unit 4a can appropriately generate a movement trajectory signal, and even in the HU mode, the movement trajectory of objects to be detected, such as islands or other ships, can be properly generated. Can be displayed.

FIG. 2 shows another embodiment of the invention. In this embodiment, in addition to the function of the above embodiment (displaying the movement trajectory of the object to be detected), it is configured to perform scan correlation processing to remove unnecessary waves such as reflections from the sea surface. The scan correlation process is a process for creating data for one rotation using, for example, received signals for 10 rotations of the antenna,
To explain briefly, first, the echo signal of the first round and the echo signal of the second round are
Compare the echo signal of the third round to create comparison result data according to a certain rule, then compare the comparison result data with the echo signal of the third round, and create new comparison result data. By sequentially repeating the same processing as described above, images caused by unstable reflections such as sea surface reflections are removed. That is, to perform scan correlation processing, the current echo signal and past echo signals are used.

The write data creation section 4 performs scan correlation processing based on the current echo signal given from the buffer memory 3 and the past echo signal read out from the processing memory 8, and converts it into data for image display. . The output data from the write data generation unit 4 is written to the processing memory 8 based on the write address generated by the second write address generation unit 9, and is also written to the write address generated by the first write address generation unit 5. based on the frame memory 6. The data written in the frame memory 6 is read out based on the read address generated by the read address generation section 7 according to the raster scan method. The read data is displayed as an image on a display device such as a CRT (not shown).

Note that the second write address generation section 9 for the processing memory 8 is configured to always generate a write address determined by the display mode of the NU mode or the CU mode from the output signal of the write data generation section 4. . First write address generator 5 for frame memory 6
converts the output signal of the write data creation unit 4 into the display mode (NU mode, HU mode,
It is configured to generate a write address determined by the CU mode.

That is, in the processing memory 8, data is always written to a storage element having a write address determined by the NU mode or the CU mode, and the frame memory 6
In this case, data is written to a memory element having a write address determined by the display mode at that time. Specifically, for example, course θG = 90°, antenna direction θA =
90° and the display mode is set to HU mode, the data map of the processing memory 8 is as shown in FIG. 3, and the data map of the frame memory 6 is as shown in FIG. In other words, the data written to the frame memory 6 is the data written to the processing memory 8 plus the course θG. Other than this point, the data written to the processing memory 8 and the data written to the frame memory 6 are exactly the same, only that the contents of the processing memory 8 are rotated and written to the frame memory 6 when writing.

Note that when the NU mode or the CU mode is set, the processing memory 8 writes data into a memory element having an address determined by north or the direction in which the ship is traveling, respectively. , the echo signal may be written in a memory element determined based on this direction.

In this way, even when the HU mode is specified, the processing memory 8 is always set to the NU mode or the C mode.
Since data is written to the storage element having the write address determined by the U mode, the past data in the processing memory 8 and the current data in the buffer memory 3 can be accurately matched, and the scan correlation process can be performed correctly.

In the above embodiment, reading for display on the display is performed using the raster scan method, and both the first write address generation section and the second write address generation section perform coordinate conversion from polar coordinates to rectangular coordinates. Although an example is given in which the obtained address signal is applied to the frame memory and the processing memory, it is also possible to perform reading for display on the display using a spiral scan method. Even in the case of this spiral scan method, it is not necessary for both the first write address generation section and the second write address generation section to perform coordinate conversion from polar coordinates to rectangular coordinates.

[0037]

As explained above, according to the first radar device of the present invention, when the bow line of the own ship constantly changes, the specified display mode can be changed to HU mode, NU mode, or CU mode. No matter what, it becomes possible to properly display the movement trajectory of objects to be detected, such as islands or other ships.

As explained above, according to the second radar device of the present invention, in addition to the effects of the first radar device, the specified display mode can be Regardless of whether it is in HU mode, NU mode, or CU mode, scan correlation processing can be performed correctly, and unnecessary waves such as sea surface reflections can be accurately removed to accurately display the surrounding situation. play.

[0039] The present invention applies to any of the above radar devices, especially when displaying when the own ship is stopped or when the own ship is moving but the amount of movement can be ignored. It's more effective.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of a radar device according to an embodiment of the present invention.

FIG. 2 is a configuration block diagram of a radar device according to another embodiment of the present invention.

FIG. 3 is a data map diagram of a processing memory in FIG. 2;

FIG. 4 is a data map diagram of the frame memory in FIG. 2;

FIG. 5 is a schematic diagram showing a display image in a conventional NU mode.

FIG. 6 is a schematic diagram showing a display image in a conventional HU mode.

FIG. 7 is a schematic diagram showing a display image in a conventional CU mode.

FIG. 8 is a configuration block diagram of a conventional radar device.

[Explanation of symbols]

1 Receiver 2 A/D conversion section 3 Buffer memory 4 Write data creation section (correlation means) 5 First write address generation section 6 Frame memory (second memory) 7 Read address generation section 8 Processing memory (third memory) 9 2nd write address generation section

Claims (2)

[Claims] Claims: 1. A receiver for receiving echo signals in a radar device that receives returning echo signals by sequentially emitting detection signals in different directions and displays surrounding conditions in a wide range of directions on a display; a buffer memory that temporarily stores an echo signal caused by a detection signal sent from the first memory; a first memory that stores signals given from the signal processing means described below at address positions determined with reference to a predetermined azimuth; A movement trajectory signal (a signal representing the movement trajectory of an object to be detected such as an island or another ship) obtained by signal processing the current echo signal to be output and the past echo signal read out from the first memory is stored in the first memory. and a second memory for storing the movement trajectory signal outputted from the signal processing means at an address position determined by the set display mode, respectively;
A radar device comprising: a display device that displays signals read from a memory. 2. A radar device that receives returning echo signals by sequentially emitting detection signals in different directions and displays surrounding conditions in a wide range of directions on a display, comprising: a receiving unit that receives echo signals; a buffer memory that temporarily stores an echo signal caused by a detection signal sent from the first memory; a first memory that stores signals given from the signal processing means described below at address positions determined with reference to a predetermined azimuth; A movement trajectory signal (representing the movement trajectory of an object to be detected such as an island or another ship) obtained by signal processing the current echo signal to be output and the past echo signal read out from the first memory is transmitted to the first memory and Second
A second memory stores signals outputted from the signal processing means and the correlation means at address positions determined by the set display mode, and a signal processing means given to the memory, and a second memory stores the signals outputted from the signal processing means and the correlation means, respectively, in a predetermined direction. A third memory stores each at an address position determined as a reference, correlates the current echo signal output from the buffer memory and past echo signals read from the third memory, processes the correlation, and stores the output signal in the third memory. A radar apparatus characterized by comprising: correlation means for applying to a second memory; and a display for displaying a signal read from the second memory.