JPH01277786A - Wave display apparatus - Google Patents

Abstract

PURPOSE:To represent waves of three-dimensional shapes from two-dimensional radar signals, by a method wherein reflected waves from the waving surface of the sea are subjected to logarithmic amplification and an output thus obtained is deviated vertically in proportion to a crest value and displayed at a corresponding position in a display coordinate axis. CONSTITUTION:In a crest value matching circuit 3, the mean value of wave heights from a wave height sensor 2 is set as a deviation coefficient of the height on a wave height axis in an actual display scale, and when a radar signal is inputted from a logarithmic characteristic radar reception element 1, it is displayed finally in the amount of deviation corresponding to its value in a raster scan CRT display unit 11. In order to obtain a display in a birds-eye view, moreover, a trigger input signal 4 is used as the origin of distance coordinates and a distance is taken for the coordinates of a scale approximating to a logarithmic scale wherein the distance is reduced gradually as it becomes long, in a non-linear distance signal circuit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a wave display device using a radar device that displays waves in accordance with the actual situation by a three-dimensional display on a display and a technique of withdrawal.

(Prior Art) In the conventional display of bird charts, emphasis is placed on the display itself, and the focus is on the simple visual understanding of the overall or limited range of the situation rather than the accuracy of the displayed information. It has been used for the purpose of Even on radar screens, examples of expression using bird withdrawal have been published in papers.

However, the height displayed on the display screen from these radar signals is simply proportional to the reflected intensity of the radar signal, and is not proportional to the physical height of the target. It simply replaced the reflective ability with the deviation of the height coordinates and displayed it.

(Problem to be Solved by the Invention) Therefore, although the above method has a low gap, if there is a reflecting surface or corner reflector that has a particularly large reflected wave, the reflected wave will be large. It had the disadvantage that it was displayed as a target and did not match the reality. In particular, when radar reflection waves from the water ocean are displayed using bird withdrawal, they differ from the actual ice distribution, which causes many inconveniences in its use.

(Means for Solving the Problems) The present invention was made against this background, and consists of amplifying waves reflected from the sea surface by a logarithmic amplifier in a radar receiver, and transmitting the output to a separately provided wave height sensor. The vertical deviation is proportional to the wave height value of the output of the antenna, and this is displayed as the wave height at the corresponding position within the display coordinate axis to obtain the bird mm as seen from the antenna installation point. Examples will be described in detail below with reference to the drawings.

(Example) FIG. 1 is a block diagram showing an embodiment of the present invention.

1 is a logarithmic radar receiver, 2 is a wave height sensor, 3 is a wave height matching circuit, 4 is a trigger input signal, and 5 is a non-linear distance
6 is an antenna rotation signal, 7 is a display orientation range selection panel, 8 is a sector gate circuit, 9 is a polar coordinate memory circuit, 10 is a coordinate conversion circuit, and 11 is a rask scan CRT display.

The signal level from the wave surface is determined by the logarithmic radar receiver 1.
is output with logarithmic characteristics. On the other hand, the wave height sensor 2 outputs a signal indicating the wave height value of the sea surface. Generally measured wave height values are averaged based on his observed values of over 100 waves, and do not indicate the wave height value at each moment at a specific point. Therefore, in the wave height value matching circuit 3, the average value of the wave heights from the wave height sensor 2 is determined as the deviation coefficient of the height on the wave height axis on the actual display scale, and the radar signal is input from the logarithmic characteristic radar receiver 1. Then, the amount of deviation corresponding to that value is finally displayed on the RuskScan CRT display. The logarithmic characteristic radar receiving section 1 has a logarithmic characteristic because the distance characteristic of the amplitude is automatically approximately proportional to the distance, and the sense of perspective can be obtained close to the actual situation during display. Logarithmic characteristic receiver 1
Since the output signal from the radar is the radar receiver 43 signal itself, the instantaneous waves at a specific point vary in size depending on the time, but the deviation when displayed on the screen is determined based on the height deviation coefficient. As a result, reflected waves from large and small waves are deflected in proportion to their size and the coefficient.

The Yi1 distance measurement scale in radar is a constant straight line regardless of distance, but in order to display a bird's-eye view, the non-linear distance signal circuit 5 uses the trigger input signal 4 as the origin of the distance coordinates, and the distance is determined as a long distance. Let the coordinates be on a scale close to a logarithmic scale, such that the scale is gradually reduced by .

Further, on the sea, the sea surface is limited to the range of visibility of the horizon, so the distance coordinates may be determined so that the farthest limit converges to the horizon.

The coordinate signal representing the distance m coordinate and the signal representing the amplitude of the radar at that coordinate are sent to the polar coordinate memory circuit 9, where they are converted into digital data (No. 3) and stored.

On the other hand, when the antenna rotation a No. 8 6 is sent from the radar to the sector gate circuit 8 and the displayed azimuth range is selected on the display azimuth range selection panel 7, the sector gate circuit 8
Then, a sector gate signal for the time from the start angle to the end angle of the azimuth selected by the antenna rotation signal 6 is generated, and during this sector gate signal, the mote coordinate signal and the radar signal at the coordinate are sent to the polar coordinate memory circuit 9. and memorized.

These polar coordinates are read by the next coordinate conversion circuit 10 and converted into XY oblique linear coordinates having an angle corresponding to the sector angle.

The coordinate axes of this coordinate conversion circuit 10 and the radar signals at those coordinates are displayed on the RaskScan CRT display 10, but this display gradually shrinks as the distance from the radar increases, and from each point. The amount of vertical deviation upward becomes a detailed map that expresses the wave height value at that point.

This bird's-eye view normally shows a view from above from the installation position of the antenna, but a view from a hypothetical point can also be obtained by moving the coordinate origin, which is generally performed in image processing.

(Effects of the Invention) As described above, the present invention allows images of waves to be displayed as if they were 3D images of the actual scene, and in a situation similar to the actual wave height, and to detect waves in a 3D shape from a 2D radar signal. It has the advantage that it can be expressed in a shape that is close to the actual shape.

[Brief explanation of the drawing]

3... Peak value matching circuit, 4... Trigger input signal, 5... Non-linear distance signal circuit, 6... Antenna rotation signal, 7... Display azimuth range selection panel, 8...・Sector gate circuit, 9...Polar coordinate memory circuit, 10...
-Coordinate conversion circuit, 11...Rusk scan CRT display. Patent applicant Japan Radio Co., Ltd.

Claims (1)

[Claims] In a radar device installed on a ship or on the coast, the reflected signal from the wave surface is amplified by a logarithmic amplifier, and the output is made proportional to the wave height value from the wave height sensor to obtain a vertical deviation, and the distance axis of the display is Convert the arrival time scale of the reflected wave, which is proportional to the straight line distance of As shown in the figure, the installation point of the radar antenna is one point, and the distance axis radiating from that point in the pointing direction of the radar antenna is an oblique axis, and the vertical deviation corresponding to the wave height value is displayed at the corresponding position of the oblique coordinates. A wave indicator configured to obtain a bird's-eye view from the viewpoint of the installation point or hypothetical point of the radar antenna.