JP3388037B2 - Marine radar equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radar device for a ship which stores a radar image signal acquired by a rotating antenna in a rectangular coordinate format in a frame memory and reads and displays it in a raster scan system. The present invention relates to improvement of a display mode switching display method.

[0002]

2. Description of the Related Art FIG. 2 shows an example of the configuration of a conventional radar device for ships. In FIG. 2, the CPU circuit 11b controls each unit and realizes various functions of the device, but basic transmission / reception and display operations are performed as follows.

The antenna 1 is rotationally driven in a horizontal plane.
The handset control circuit 10 receives a transmission command from the CPU circuit 11b and causes the antenna 1 to transmit a pulsed radio wave.
The reflected wave from a target such as another ship existing around the ship (within the radar range) equipped with the radar device is the antenna 1
Will be received at.

One transmission / reception operation until the antenna 1 transmits at a certain azimuth angle and receives the reflected wave at the end of the radar range is called one sweep. The received signal (radar image signal) acquired by the antenna 1 Sequentially A / D according to the order of reception
The conversion circuit 2 digitizes the image data into radar image data, which is sequentially stored in the sweep memory 3 for each sweep by a write clock (not shown) that divides one sweep period.

The radar image data stored in the sweep memory 3 is sequentially read for each sweep by a read clock (not shown) asynchronous with the write clock, and is supplied to the radar image frame memory 5 as write data. The write address of the radar image frame memory 5 is generated in the coordinate conversion circuit 4b as follows.

That is, the bit position of the radar image data stored in the sweep memory 3 is expressed in the polar coordinate format of (R, θ) defined by the distance R from the ship position to the target and the relative azimuth θ. Therefore, in order to display the image on the CRT display 9 by the raster scan method, it is necessary to express the bit position of the radar image data in the orthogonal coordinate format of (X, Y). The coordinate conversion circuit 4b realizes the coordinate conversion of (R, θ) → (X, Y) by setting the write address to the radar image frame memory 5 to (X, Y).

Specifically, the reading from the sweep memory 3 is sequentially performed from the origin position of the sweep (own ship position) toward the end of the radar range. Therefore, the number of read clocks corresponds to the bit position of the data on the sweep memory 3, and indicates the distance R of the target from the own ship position.

The angle signal control circuit 7 is controlled by the CPU circuit 11b such as setting an initial value. The angle signal control circuit 7 receives a pulse-shaped antenna rotation signal from the antenna rotation signal generation circuit 6 in response to the rotation of the antenna 1 and outputs the antenna signal. An angle signal indicating the azimuth of 1 is formed. This angle signal is the relative azimuth angle θ of the target.

Therefore, every time a data bit is read from the sweep memory 3, the coordinate conversion circuit 4b obtains the distance R from the read clock and the angle signal θ from the angle signal control circuit 7 to calculate the formula 1. And then (R,
The position of the data bit defined by the polar coordinates of (θ) is converted to the position defined by the Cartesian coordinates of (X, Y) with reference to the ship position (X _S , Y _S ) and the position (X, Y ) Is given to the radar image frame memory 5 as a write address to write the data bit read from the sweep memory 3.

[0010]

[Formula 1] X = X _S + R · sin θ Y = Y _S + R · cos θ

The coordinate conversion is performed in this way, and the radar image data for each radar scan is sequentially stored in the radar image frame memory 5. In parallel with the above operation, the radar image frame memory 5 stores the radar image data. Radar image data for each scan is taken out in order according to the scan order of the raster scan, converted into analog by the D / A conversion circuit 8, and CR
The radar image is displayed on the T display 9 by the raster scan method.

Further, the CPU circuit 11b controls the graphic control circuit 12 to give an instruction such as a cursor to be displayed as part of realizing various functions of the marine vessel radar device. As a result, the graphic control circuit 12 generates graphic data. This graphic data is once stored in the graphic frame memory 13, read out from the graphic frame memory 13, converted into an analog signal by the D / A conversion circuit 8, and superimposed and displayed on the CRT display 9 with the radar image for the convenience of the observer. It

For the display on the CRT display 9, a combined display system of exercise and heading is adopted. Specifically, this combination display method includes a relative movement and head-up combination display method, a relative movement and north-up combination display method, a true movement and north-up combination display method, a relative movement and course. There are 5 types of combination display system of up and combination display of true motion and course up, but in many cases, combination display of true motion and north up with combination display of relative motion and head up. Is adopted, and the radar observer can switch and use it depending on the time and the case.

That is, although not shown, the CPU circuit 11b is adapted to receive a display system instruction from the operation panel, and the coordinate conversion circuit 4b generates a write address for the radar image frame memory 5 as described above. At this time, using the speed signal input from the ship speed signal interface circuit 14 and the angle signal of the own ship input from the gyro interface circuit 15, the display on the CRT display 9 is a combined display instructed by the radar observer. The control signal for generating the write address is calculated and generated, and the calculated control signal is given to the coordinate conversion circuit 4b. As a result, one combination display designated by the radar observer is displayed.

For reference, the contents of the exercise method and the heading method will be briefly described. "Relative movement method"
This is a method in which the center of the image (own ship position) is fixed to one point on the display screen (the center of the circle on the display screen is large), and the echo is displayed relative to the own ship. In this method, even when the echo is stationary, the echo moves and is displayed along with the movement of the ship. The "true movement method" is a method in which the upper part of the screen is fixed to the north with respect to the echo to be displayed, and the bow is displayed on the nautical chart in the direction in which the ship is actually moving. In this method, the center of the image moves with the movement of the ship. Therefore,
A moving echo is displayed by moving in the actual moving direction, and a stationary echo is displayed at the same position.

The "head-up system" is a system in which the bow is always fixed to the upper part of the screen regardless of the direction in which the ship is headed, and the image actually viewed from the bow of the ship is displayed. The "North-up method" is a method in which the upper part of the screen is fixed to the north, and the bow is oriented in the actual direction. With this method, it is displayed on the nautical chart as if the ship were actually moving. "Course-up system" is a system located between "head-up system" and "north-up system". The bow is fixed at the top of the screen immediately after selecting course-up, but like the north-up system. Even when the ship yaws, the fixed target does not fluctuate and is displayed in a stable manner, at which time the bow rotates by the angle the ship yaws.

In the combined display system of relative motion and head-up, the echo similar to the view of the outside actually seen from the bridge is displayed, so that the view and the echo can be grasped on a one-to-one basis and the observation can be performed. The display is very easy for the person to understand. Also, in the combined display method of true movement and north up, when you are steering while looking at the nautical chart or when you are actually synthesizing the nautical chart etc. on the screen, you can see that you are actually going to the destination It provides a display that is very easy to steer. In this method, the movement of the echo is a true movement, and it indicates the direction and speed that is actually moving. Therefore, when using the function to display the track of another ship, at which speed is it actually moving? Will understand immediately. This method is often used because it has such characteristics.

[0018]

In the radar device for a ship, the acquired radar image is displayed by a method of a combination of motion and head-up, but conventionally, one combination display is changed to another one. When switching the display mode to the matching display, the contents of the frame memory are first rewritten and then displayed, so it is not possible to switch instantly, and when the display mode was restored again, it was possible to display the previous time. There is a problem that the tracks of other ships are already deleted and not displayed. This problem occurs not only when the combination display is switched, but also when one combination display is used, for example, when the observation range is switched.

The present invention has been made in view of such a problem, and an object thereof is to be able to instantaneously switch a plurality of display modes different from each other, and to repeatedly display the contents of the previous display. It is an object of the present invention to provide a radar device for a ship equipped with a radar image display system capable of displaying.

[0020]

In order to achieve the above object, the marine vessel radar apparatus of the present invention has the following configuration. That is, the marine vessel radar device of the present invention includes a plurality of radar image frame memories that store radar image data in a rectangular coordinate format; and a write address for the corresponding memory of the plurality of radar image frame memories is acquired for each sweep. A plurality of coordinate conversion circuits that generate the distance information and the angle information related to the radar image according to the display mode control signal; and the display for each of a plurality of different display modes designated from the outside or predetermined. Means for generating a mode control signal; means for receiving a display mode designation signal input from the outside and outputting a memory designation signal for designating a corresponding memory of the plurality of radar image frame memories; The contents of a designated memory among the plurality of radar image frame memories are And a display switching circuit for sending out to a read-out display system.

The plurality of display modes different from each other are, for example, a combination display mode of a plurality of motions and headings different from each other, and a display mode of a plurality of observation ranges different from each other.

[0022]

Next, the operation of the marine vessel radar apparatus of the present invention constructed as described above will be described. In the present invention, a plurality of systems of a coordinate conversion circuit and a radar image frame memory are provided, radar images according to different display modes are stored in advance in each system, and the contents of the memory are read out according to the memory designation signal and sent to the display system. To do.

Thus, according to the present invention, it is possible to instantaneously switch the display modes such as switching between different combinations of displays and switching of the observation range. At this time, since the contents of the frame memory are saved, the contents of the previous display can be displayed in a continuous form by switching again and again.

[0024]

Embodiments of the present invention will be described below with reference to the drawings. The same components as those of the conventional example (FIG. 2) are designated by the same reference numerals. FIG. 1 shows a ship radar device according to an embodiment of the present invention. As mentioned above, the indicator (CRT
For display on the display, a combination display method of movement and heading is adopted. There are 5 types of ~, but in many cases, the true movement of the combination display method of relative movement and head up is used. The combination display method of and Northup is adopted.

Therefore, in the present embodiment, in the conventional ship radar device, two systems of (4a, 5) (16, 17) are provided for the coordinate conversion circuit and the radar image frame memory.
A display switching circuit 18 is provided between them and the D / A conversion circuit 8 to add some functions to the CPU circuit 11a.
Hereinafter, the description will focus on the part relating to the present invention.

In FIG. 1, the CPU circuit 11a is provided with two display systems out of the five display systems of, for example, "combined display system of relative motion and head up" and "from the operation panel (not shown). A combination display method of true movement and North Up "is designated. Alternatively, if the combination display mode of the radar device is only two display systems, C
In the PU circuit 11a, for example, two display modes of "combination display method of relative movement and head-up" and "combination display method of true movement and north-up" are predetermined.

The coordinate conversion circuit 16 generates a write address for the radar image frame memory 17, similarly to the coordinate conversion circuit 4a for generating a write address for the radar image frame memory 5. At that time, the CPU circuit 1
When the content of the radar image frame memory 5 is displayed on the CRT display 9 by using the speed signal input from the ship speed signal interface circuit 14 and the ship's angle signal input from the gyro interface circuit 15, 1a indicates “ According to the display method of the combination of relative motion and head-up, the contents of the radar image frame memory 17 are CR.
When displayed on the T display unit 9, the display mode control signals for generating the write addresses that are in accordance with the "combination display method of true motion and north up" are respectively calculated and generated, and the coordinate conversion circuit 4a is generated. And give to 16 corresponding ones.

Then, the CPU circuit 11a decodes the display mode designation signal input from the operation panel (not shown), and if the designated display mode is "combined display system of relative motion and head up", the radar image frame memory If 5 is designated and the designated display mode is “combination display system of true motion and north up”, radar image frame memory 1
A memory designating signal designating 7 is output to the display switching circuit 18.

The display switching circuit 18 selects a designated radar image frame memory from the two radar image frame memories according to the memory designation signal input from the CPU circuit 11a, reads out the contents of the selected memory, and displays the display system ( It is sent to the D / A conversion circuit 8).

As a result, the combination display instructed by the radar observer is instantly switched and displayed. Even when the display mode is returned to the original display mode, the content of the previous display is saved in the frame memory while undergoing a slight correction due to the movement of the ship or another ship, so the content of the previous display maintains continuity. It is displayed as

As is clear from the above description, it should be noted that it is also possible to easily change one or both of the display methods during the operation to other combined display methods (,,). .

Further, with the configuration of FIG. 1, switching display in two observation ranges is also possible. If the combination display of exercise and heading is one of the above five types, and there are two observation ranges of 0.25 miles and 24 miles, CP
The U circuit 11a generates a write address for one combination display to the two coordinate conversion circuits, but simultaneously operates the two coordinate conversion circuits at different conversion speeds and adapts the respective coordinate conversion circuits to the conversion speed. The read clock is output to the sweep memory.

As a result, the radar image frame memory 5 stores the radar image data in the 0.25 mile range, and the radar image frame memory 17 stores the radar image data in the 24 mile range. The range instructed by the radar observer is instantaneously switched and displayed, and when the range is returned to the original, the previously displayed contents are displayed with continuity.

[0034]

As described above, the marine radar device of the present invention is provided with a plurality of systems of a coordinate conversion circuit and a radar image frame memory, and each system stores radar images according to different display modes in advance. Since the contents of the memory are read out and sent out to the display system in accordance with the memory designation signal, it is possible to instantaneously switch the display modes such as switching between different combinations of displays and switching of the observation range. At this time, since the contents of the frame memory are saved, there is an effect that the contents of the previous display can be displayed in a form of maintaining continuity by switching again and again any number of times.

[Brief description of drawings]

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

FIG. 2 is a configuration block diagram of a conventional marine radar device.

[Explanation of symbols]

1 antenna 2 A / D conversion circuit 3 sweep memory 4a, 16 Coordinate conversion circuit 5,17 Radar image frame memory 6 Antenna rotation signal generation circuit 7 Angle signal control circuit 8 D / A conversion circuit 9 CRT display 10 Handset control circuit 11a CPU circuit 14 Ship speed signal interface circuit 15 Gyro interface circuit

Continuation of front page (58) Fields investigated (Int.Cl. ⁷ , DB name) G01S ⁷ /00-7/42 G01S 13/00-13/95

Claims (3)

(57) [Claims] 1. A plurality of radar image frame memories for storing radar image data in a rectangular coordinate format; a distance related to a radar image obtained by writing a write address to a corresponding memory of the plurality of radar image frame memories for each sweep. A plurality of coordinate conversion circuits that generate information and angle information in accordance with a display mode control signal; generate the display mode control signal for each of a plurality of different display modes that are specified externally or are predetermined. Means for receiving a display mode designation signal inputted from the outside and outputting a memory designation signal for designating a corresponding memory of the plurality of radar image frame memories; and a plurality of radar image frames for receiving the memory designation signal. Reads out the contents of the specified memory, and sends it to the display system. Marine radar apparatus characterized by comprising; a display switching circuit. 2. A plurality of display modes different from each other comprises a combination display mode of a plurality of motions and headings different from each other; the display mode control signal uses a ship speed signal and an angle signal of the own ship which are given from the outside. The radar device for a ship according to claim 1, wherein: 3. A plurality of display modes different from each other comprises a display mode of a plurality of observation ranges different from each other; the display mode control signal is a control signal of a read speed and a coordinate conversion speed of a radar image given to a radar image frame memory. The marine radar device according to claim 1, wherein: