JP3010454B2 - Radar display - 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 display device for displaying an image captured by a radar mounted on a moving body such as a ship.

[0002]

2. Description of the Related Art A radar device mounted on a ship emits a pulse-like radio wave at a constant period while rotating an antenna composed of a slot antenna or the like at a constant speed in all directions over 360 ^° , and reflects the reflected wave. It is configured to detect the presence and position of the object that caused the wave by receiving the wave. The elapsed time from the emission of a radio wave to the reception of its reflected wave represents the distance (r) from this ship to the object, and the direction of the antenna at the time of receiving the reflected wave is the direction (θ) of the object as seen from this ship. Therefore, a polar coordinate system with the ship as the origin is suitable as a coordinate system for displaying the detection result of the position of the object by the radar, and the object is displayed on a display screen of a CRT or the like using such a polar coordinate system. The intensity of the reflected wave is displayed as the intensity of the luminance.

In the above-mentioned radar display device using a CRT or the like, if the sweep on the display screen by the electron beam is performed in a polar coordinate system, the deflection mechanism of the electron beam becomes complicated and expensive. For this reason, recently, coordinate conversion is performed in which position information in a polar coordinate system is converted into position information in an orthogonal XY coordinate system, and displayed while sweeping in horizontal and vertical directions as in a normal television receiver. Raster scan type display devices with means interposed have been used.

Recently, with the spread of GPS and the like, high-performance navigation devices capable of detecting the position, course, and the like of the ship itself have been equipped on relatively small ships and the like.

[0005]

In the radar system in which the conventional radar device and display device are combined, the relative positional relationship (distance and direction) between the ship and the object can be detected. The position must be detected by a separately installed navigation device. As described above, since the radar system that detects the relative positional relationship with respect to the own ship and the navigation system that detects the absolute position of the own ship have been developed separately, the integration of both has been discussed. The situation has not been fully examined. That is, when trying to detect the absolute position of any object selected on the radar display screen, the absolute position of the ship detected by the navigation device and the relative positional relationship between the object detected on the radar display screen are determined. It is necessary to perform drawing and calculation based on manual work or using a computer separately, and there is a problem that labor and time are required.

[0006]

SUMMARY OF THE INVENTION A radar display device according to the present invention is based on means for receiving, from a navigation device, information on the absolute position of a moving body on which the radar is installed, and designation of an arbitrary point on a display screen. Input means for inputting information on a relative positional relationship between this point and the moving object; information on an absolute position of the moving object received from the navigation device; information on a relative positional relationship input by the input means; And an absolute position calculation and display control means for calculating an absolute position of an arbitrary point designated on the display screen based on an appropriate drawing method and displaying the calculated absolute position at a predetermined position in the display screen. The system is configured so that the absolute position of the arbitrary object selected above can be instantaneously detected with high accuracy.

[0007]

FIG. 1 is a block diagram showing the configuration of a radar display device according to an embodiment of the present invention in connection with a radar device 20. 1 is a CPU, 2 is an input interface unit, 3 is an input unit, and 4 is an input unit. A / D converters, 5 and 8 are VRAMs, 6 is an address calculator, 7 is a drawing processor, 9 is a signal synthesizer, 1
0 is a D / A converter, and 11 is a display. In the radar device 20, reference numeral 21 denotes a variable clock generator, reference numeral 22 denotes a timing signal generator, reference numeral 23 denotes a transmitter, reference numeral 23 denotes an antenna, reference numeral 25 denotes a receiver, and reference numeral 26 denotes an antenna driver.

[0008] The variable clock generation circuit of the radar device 20 generates a variable clock signal designated by the CPU 1 of the radar display device and supplies it to the timing signal generation unit 22.
The timing generation unit 22 generates various timing signals from the variable clock signal supplied from the variable clock generation unit 21 and supplies the timing signals to each unit in the radar device 20 and each unit in the radar display device. Is performed.
The antenna 24 composed of a slot antenna or the like emits a pulse-shaped electric signal of a predetermined period supplied from the transmission unit 23 through a conventional circuit such as a circulator or a rotary joint while being rotated at a constant speed by the antenna driving circuit 24. I do. A reflected wave generated by an object present on the propagation path of the radiated radio wave is received by the antenna 24 along a path opposite to the radiated radio wave, amplified by the receiving unit 25, and then A / D converted by the radar display device. It is supplied to the unit 4.

The A / D converter 4 converts the analog reception signal received from the radar device into a digital signal having a predetermined bit width at a predetermined sampling rate, and supplies the digital signal to the VRAM 5. The address calculation unit 6 calculates a write address for converting a polar coordinate system having its own origin on the radar device 20 side into a rectangular coordinate system on the radar display device side, and performs a VRAM operation.
5 and at regular intervals in the vertical coordinate system,
A read address that is incremented in the horizontal direction is supplied to the VRAM 5. The signal read from the VRAM 5 is supplied to the display unit 11 via the synthesizing unit 9 and the D / A conversion unit 10, and is displayed on a display screen.

The input unit 3 includes a key switch and a rotary switch formed on a panel surface of a housing for accommodating the display unit 11, and inputs various commands related to display such as a change of a display range and a scale line. I do. The CPU 1 has an input unit 3
Receives various commands input from the input interface unit 2 via the input interface unit 2 and decodes them to control the operation of each unit.
Alternatively, a drawing command is issued to the drawing processor 7. The drawing processor 7 responds to a drawing command received from the CPU 1
A fixed scale line displayed on the display screen of the display unit 11,
RM (Valuable Range Marker) and EBL (Electronic B
A display data such as a variable scale line such as an earing line or an alphanumeric character indicating the range being displayed is created and written into the VRAM 8. The display data written in the VRAM 8 is read out from the VRAM 8 at a constant period, and supplied to the display unit 11 via the D / A conversion unit 10 while being superimposed on the image of the object read out from the VRAM 5 in the synthesizing unit 9. Will be displayed.

Further, an antenna driving unit 26 of the radar device 20 is connected to the input interface unit 2 via a signal line, and a bow signal generated each time the antenna 24 turns to the bow direction and a bow direction are generated. Antenna 2 as reference
The signal indicating the angle of 4 is transferred to the CPU 1 via the input interface unit 2. Further, an absolute azimuth detecting device such as a gyro or a magnet compass is also connected to the input interface unit 2 via a serial transmission line.
The detected heading signal is transferred to the CPU 1 via the transmission path and the input interface unit 2. Further, the input interface unit 2 includes GPS, Loran C,
Navigation devices such as NNSS and OMEGA are connected via a serial transmission line, and the own ship position signal detected by this navigation device is transmitted to the C line via the transmission line and the input interface unit 2.
Transferred to PU1.

When the head-up mode is specified as the display mode of the display screen, the CPU 1 sets the heading of the display screen directly above the display direction on the basis of the heading signal and the heading signal received via the input interface unit 2. The orientation of the display screen is controlled via the address calculation unit 6 so as to match When the north-up mode is designated as the display mode of the display screen, the CPU 1 matches the north directly on the display screen based on the heading signal and the bow signal received via the input interface unit 2. The orientation of the display screen is controlled via the address calculation unit 6 as described above.

As shown in FIG. 2, the display screen of the display section 11 displays concentric fixed scale lines arranged at equal intervals around the own ship and also displays the fixed scale lines around the own ship. Radial fixed graduation lines arranged at an angle are displayed. The image of the object detected by the radar device 20 is apparently displayed in the form of polar coordinates based on a combination of a distance (r) and an angle (θ) from the origin with the own ship as the origin. This image is displayed by horizontal and vertical raster scans by the coordinate conversion by the address calculation unit 6 as shown in FIG. In addition to the fixed scale lines, a variable concentric scale line (VRM) and a radial scale line (EBL) are displayed according to a command from the input unit 3 so as to reach any point on the display screen. The distance (r) and the angle (θ) can be read.
Around the display screen, numerical data such as a currently selected range is also displayed.

As shown in FIG. 2, a cross cursor is displayed on the display screen.
The display screen can be moved from a predetermined initial position to an arbitrary position on the display screen in accordance with horizontal and vertical movement commands input from the device. In the radar display device of the present embodiment,
With the cross cursor positioned at an arbitrary point in the display screen, the input unit 3 can instruct calculation and display of the absolute position of the arbitrary point.

When the CPU 1 receives the instructions for calculating and displaying the absolute position, the CPU 1 converts the position of the cross cursor into a distance r from the ship and an angle θ, and stores the Mercator projection and large circles stored in the built-in ROM. A predetermined algorithm based on a drawing method or the like is executed. When a plurality of projections are stored in the ROM in the CPU 1, the input unit 3 specifies which projection is to be applied. For example, when applying the Mercator projection, if the latitude and longitude of the ship are (φ ₀ , λ ₀ ), the latitude and longitude (φ ₁ , λ ₁ ) of the point designated by the cross cursor
Is calculated according to the following equation. _{φ 1 = φ 0 + ΔLat λ} 1 = λ 0 + ΔLong ΔLat = r cosθ ΔLong = MΔLat tanθ MΔLat = 7915.7 _{[log 10 tan (π / 4 +} φ 1/2) -log 10 tan (π / 4 + φ 0/2) ]

In the great circle projection, φ ₁ = sin ⁻¹ [sin φ ₀ · cosr + cosφ ₀ · sinr · cos θ] λ ₁ = Tan ^-1 [(sin θ) / (cos r · cosφ 0 - sinφ 0 · cos θ) ] + lambda ₀ CPU 1, when calculating the latitude and longitude is completed, the drawing data of numbers representing the latitude and longitude The creation is instructed to the drawing processor 7 and displayed as an appropriate blank portion in the display screen, for example, a lower right corner of the display screen as a cursor position.

The above-described detection of the absolute position of an arbitrary point away from the own ship is used in the following cases. As an example, in a state where a large number of fishing boats belonging to a plurality of fleets are operating in a complicated manner, which one of the many boat shadows of a fishing boat belonging to a certain fleet is being captured in its radar display screen is the shadow of a consignment ship of interest. May be specified on the radar display screen. In this case, first, the current position is heard from the consort ship using the wireless communication device, and then the absolute position is detected by positioning the cross cursor on the shadow of the new ship on the display screen, and the current position is detected by wireless communication. By collating with the position, it is possible to confirm whether or not the shadow of the ship to which the cross cursor is placed is the convoy of interest according to the collation result.

Alternatively, the absolute position of an image of land and the like being captured on the radar display screen is displayed on the display screen, and the object present at the absolute position is confirmed on a marine chart or the like, so that the ship can communicate with the ship. The comparison between the display screen displayed at the relative position and the chart displayed at the absolute position can be easily performed.

Further, the position of the own ship can be displayed on the display screen by instructing the calculation and display of the absolute position with the cross cursor set to the position of the own ship.

The example in which an arbitrary point on the display screen whose absolute position is to be detected is designated by the cross cursor has been described above. However, the designation of this arbitrary point is
Or any other suitable method such as by using the intersection of variable scales such as EBL and EBL.

Further, the configuration in which the absolute position of the cross cursor is calculated and displayed in accordance with a special command from the input unit has been exemplified. However, conversely, the configuration may be such that the intersection of the cross cursor or the variable scale is constantly calculated and displayed until a special release command is input from the input unit.

Furthermore, the present invention has been described by taking the case of a ship as a moving body as an example, but the present invention can be applied to other appropriate moving bodies such as land vehicles.

[0023]

As described in detail above, the radar display device of the present invention receives information on the absolute position of a moving object from the navigation device, and designates an arbitrary point on the display screen to determine the relative position with the moving object. The system has a means for inputting information on the general positional relationship and calculating and displaying the absolute position of the point based on each information and an appropriate projection, so that any object selected arbitrarily on the radar display screen Can be detected instantaneously with high accuracy, and the effect of greatly improving the convenience as a radar display device is exhibited.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a radar display device according to an embodiment of the present invention, in connection with a radar device.

FIG. 2 is a conceptual diagram showing an example of a display screen for explaining the operation of the radar display device of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 CPU 2 Input interface part which receives own ship position signal etc. from a navigation device 3 Input part 5 VRAM which holds the video data detected by radar 6 Address operation part which performs address operation for coordinate conversion 7 Scale lines and alphanumeric characters Drawing processor that creates display data such as 8 A VRAM that holds display data 9 Synthesizing unit 11 Display unit 20 Radar device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-146006 (JP, A) JP-A-2-49179 (JP, A) JP-A-60-164278 (JP, A) JP-A-3- 85472 (JP, A) Fully open 1986-114319 (JP, U) Fully open 1988-152574 (JP, U) Really open 3-11,786 (JP, U) (58) Field surveyed (Int. G01S ^7/ 00-7/42 G01S 13/00-13/95

Claims (2)

(57) [Claims] The position of an object detected by a radar device installed on a ship or other moving object is determined by the position of the moving object.
A radar display device for displaying on a polar coordinate display plane as a center, a means for receiving the latitude and longitude of the moving object from a navigation device, and an arbitrary point on the polar coordinate display screen by designating the arbitrary point. The distance of the point from this mobile and this mobile
Input means for inputting the angle seen from the viewpoint, the latitude and longitude of the moving object received from the navigation device, the distance and angle input by the input means, and the Mercator projection or
Calculating the latitude and longitude of an arbitrary point specified on the display screen based on Great Circle projection, and a latitude / longitude display means for displaying at a predetermined location in the display screen, Radar display device. 2. The method according to claim 1 , wherein an arbitrary point on the display screen is designated by a cross cursor.
And a radar display device.