JP3008906B2 - Radar video 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 video display device for displaying a three-dimensional radar video signal from a three-dimensional radar device, and more particularly, to displaying a three-dimensional radar video signal in a two-dimensional raster scan system. The present invention relates to a radar video display device.

[0002]

2. Description of the Related Art Conventionally, in a generally used two-dimensional radar apparatus, an entire circumference is scanned on a plane, and
Information about (range: distance) and Az (azimuth: azimuth) is obtained. However, such a two-dimensional scanning method cannot detect a target located at a position higher than the scanning plane. On the other hand, there has been proposed a three-dimensional radar apparatus which eliminates such a drawback by adding scanning in the height direction to full-circular scanning. FIG. 4 explains the concept of the all-around search of the three-dimensional radar device. In the three-dimensional radar apparatus, as shown in (a), while a radar beam is scanned in the Az direction, repetitive scanning is performed in an EL (elevation: altitude) direction in a certain range, and as a result, hatching is shown in (b). Obtain such a coverage area. In this case, the scanning in the EL direction is performed as shown in FIG.
A plurality of beams (beams 1 to n) having different heights by L, for example, sequentially scan from bottom to top, then move to the next Az position and repeat the same scanning operation again. Is done.

[0003] As a display method for displaying a radar video signal transmitted from such a three-dimensional radar apparatus on a radar video display apparatus based on a raster scan method (TV scanning method), as in the case of a two-dimensional radar apparatus. Na, P
A PI (plan position indication) display method is used. In this case, each E at the same Az position viewed from directly above
The L beams are combined and displayed on the PPI display screen. Therefore, even when video signals other than the target (for example, noise and interference signals) are present at the same distance R and the same azimuth Az and at different altitudes EL, the target video signal and the non-target video signal are displayed on the PPI screen. The video signal is
At the same time, since the two-dimensional display is performed in the form of horizontal projection, the video signal by the target and the video signal other than the target are displayed in a superimposed manner. I was

On the other hand, in the technique disclosed in Japanese Patent Application Laid-Open No. 4-283677, in order to facilitate the identification of a target, the same PPI display is used in a PPI display of a three-dimensional radar video display device employing a raster scan system. When there are video signals other than the target and the target at different distances R and the same azimuth Az and different altitudes EL, the signal strengths of the EL beams having the same distance R and the same azimuth Az are compared and determined.
By selecting the video signal having the maximum intensity as the target video signal and displaying the target video signal with the two-dimensional coordinate system of the distance R and the azimuth Az, and performing an interpolation process of expanding and displaying the target video in a fan shape around the azimuth Az, PPI
The visibility of the video display on the display has been improved.

As another display method, ECCM (el
An ectronic counter-counter measure) display method is known. The ECCM display method is an electronic counter measure (ECM) performed to prevent radar detection.
(Radio wave jamming) in which the radar beam in the azimuth Az suspected of jamming is developed in the height direction, and the video signal is subjected to luminance modulation or the like to make it easier to visually recognize, and From the situation, it is intended to discriminate a radio wave interference (chuff), noise, and the like due to aerial scattering of a metal foil performed as an ECM from a target such as an aircraft. FIG. 5 shows an example of a conventional ECCM display. In the same direction Az, beams 1 to n different in height from each other by ΔEL are developed with a distance R and an altitude EL as axes, and a radar video is displayed. By emphasizing the echo portion of the signal by subjecting it to luminance modulation, it is easy to discriminate the target from those other than the target.

[0006]

However, in the above-mentioned prior art, the first problem is that the radar video signal sent from the three-dimensional radar device is displayed on the radar video display device by raster scanning in a PPI manner. However, since the PPI display is performed by combining the EL beams of the same direction Az, when a certain EL beam is disturbed by a chaff or the like, the video signal of each EL is superimposed. There is a drawback that the video signal is hidden by the interfering video signal and cannot be seen, so that it is impossible to detect the target to be originally observed. In addition, in the case of disturbance such as a chaff, it is possible to prevent the influence of the disturbance or the like by turning off the EL beam in the direction in which the disturbance was applied and observing the beam. There is a drawback that all valid data of EL beams other than the above are invalidated.

As a second problem, when an ECCM display for displaying a vertical section in a certain direction is performed on a radar video signal transmitted from a three-dimensional radar apparatus,
Conventionally, since a video signal subjected to luminance modulation is displayed corresponding to one or two sweeps, the range of an image to be displayed is small. There was a drawback that it was not possible.

The present invention has been made in view of the above circumstances, and has as its object to provide a radar video display device that is resistant to external disturbances.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problem, the present invention is directed to a three-dimensional radar apparatus which performs scanning in an azimuth direction while repeating scanning in an altitude direction. The present invention relates to a radar video display device for displaying an image on a display means, and combines the radar video signals of the above three-dimensional radar devices in the same direction with respect to the same azimuth scanning, and converts the synthesized radar video signal of the polar coordinate system scanning into a rectangular coordinate system. Converts to a scanning radar video signal and displays it on the display means, and when radio interference exists, prohibits output of the radar video signal to the display means in the azimuth and altitude range set according to the external command The PPI scan conversion means is provided.

According to a second aspect of the present invention, there is provided the radar video display device according to the first aspect of the present invention, wherein the setting of the altitude range in the PPI scan conversion means is equal to or less than a designated altitude.
It is characterized in that it is performed in accordance with a selection between specified altitudes of an arbitrary width and a specified altitude or higher.

According to a third aspect of the present invention, in the radar video display device according to the first or second aspect of the present invention, the luminance modulation is performed on a region of the reflected signal in the converted radar video signal of the orthogonal coordinate system. Or a display converting means for performing a process of changing a display color of the display means.

According to a fourth aspect of the present invention, an image display of a radar video signal of a three-dimensional radar apparatus which performs scanning in an azimuth direction while repeating scanning in an altitude direction is provided on first and second display means of a raster scanning system. And a radar video signal for scanning in each of the altitude directions in the same direction of the three-dimensional radar device is synthesized, and a radar video signal for scanning in a polar coordinate system resulting from the synthesis is converted into a radar video signal for scanning in a rectangular coordinate system. Converted and displayed on the first display means, and when there is radio interference, output of the radar video signal to the first display means is prohibited in the azimuth and altitude range set according to the external command. PPI to do
A scan conversion means for converting a radar video signal of an altitude direction scan in a designated azimuth in a radar video signal of a polar coordinate system scan of the three-dimensional radar apparatus into a radar video signal of a distance / altitude coordinate system scan, and ECCM scan conversion means for displaying on the display means and performing interpolation processing before and after each one of the scanning beams in the altitude scanning and displaying the area on the second display means. And

According to a fifth aspect of the present invention, there is provided the radar video display apparatus according to the fourth aspect of the present invention, wherein the interpolation processing before and after the one scanning beam in the ECCM scan conversion means includes several tens interpolation processing. It is characterized in that interpolation is performed using beams.

According to a sixth aspect of the present invention, there is provided the radar video display apparatus according to the fourth or fifth aspect, wherein a luminance of a region of the reflected signal in the converted radar video signal of the distance / altitude coordinate system is set to be equal to or smaller than that of the reflected signal. A display conversion means for performing a modulation or a process of changing a display color in the second display means is provided.

[0015]

According to the configuration of the present invention, in a radar video display device that performs PPI display, when an external beam is obstructed, the EL beam of the obstructed azimuth is not higher than a designated altitude and two or more altitudes. By setting any one of the designated altitudes above the specified altitude, the effect of the disturbed video signal is removed and the PPI display is performed.
The visibility of the displayed image is improved, and the operator can continue to observe the target. Also, in a radar video display device that performs ECCM display, an interpolated beam is generated for display scanning of each EL beam, and in addition to the conventional luminance modulation, a video signal to be displayed is expanded to perform area display. Therefore, the visibility of the displayed image is improved, and the identification of the target is further facilitated.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. The description will be made specifically using an embodiment. FIG. 1 is a block diagram showing an electrical configuration of a radar video display device according to one embodiment of the present invention;
FIG. 2 is a diagram showing a PPI display mode in the device, and FIG. 3 is a diagram showing an ECCM display mode in the device. The radar video display device of this example has a video memory 1
, PPI scan conversion circuit 2, ECCM scan conversion circuit 3, PPI video frame buffer 4, ECCM
Video frame buffer 5 and composite LUT (lookup ta
blememory) 6 and a CRT (cathode ray tube) monitor 7.

The video memory 1 stores a radar video signal from a three-dimensional radar device (not shown) for each scan, and includes n (n is a positive integer) EL beam numbers 1 for scanning. .. N. PP
The I-scan conversion circuit 2 scan-converts a radar video signal read from the video memory 1 from a polar coordinate (Rθ coordinate) system to a rectangular coordinate (XY coordinate) system. The ECCM scan conversion circuit 3 scan-converts the video signal read from the video memory 1 from the Rθ coordinate system to the distance / altitude coordinate (R / EL coordinate) system, and converts the video signal for one EL beam. Performs ten interpolation processes.

The video frame buffer for PPI 4
The radar video signal converted into the XY coordinate system in the PI scan conversion circuit 2 is stored for one frame. The ECCM video frame buffer 5 stores one frame of the radar video signal converted into the R / EL coordinate system in the scan conversion circuit 3 for ECCM. The synthesis LUT 6 performs brightness control and display color control on the area of the reflection signal with respect to the data from the PPI video frame buffer 4 and the data from the ECCM video frame buffer 5, and outputs the data. The CRT monitor 7 performs a radar video display of a PPI display and a radar video display of an ECCM display on a screen of a CRT (not shown) based on an output from the synthesis LUT 6.

Hereinafter, the operation of the radar video display device of this embodiment will be described with reference to FIGS. 1, 2 and 3.
A radar video signal RVS transmitted from a three-dimensional radar device (not shown) is input to the video memory 1. 3
A control signal CTL including a radar trigger and an azimuth signal transmitted from the three-dimensional radar apparatus is transmitted to a PPI scan conversion circuit 2.
Is input to The control signal CTL is the radar video signal R
It is a signal corresponding to the polar coordinate data of Rθ in VS. The PPI scan conversion circuit 2 periodically outputs the timing control signal CLK according to the control signal CTL, and converts the radar video signal RVS into the video memory 1 of the corresponding beam number 1 to n according to the n EL scans. Once. The radar video signal VMP read from the video memory 1 is input to the PPI scan conversion circuit 2. PPI
The scan conversion circuit 2 synthesizes a radar video signal based on n EL scans from the video memory 1 and converts the radar video signal from the three-dimensional radar device, which is composed of a polar Rθ coordinate system, into two-dimensional coordinates. The image data is scan-converted into the XY coordinate system and stored as display video data PDA1 on a frame-by-frame basis in the PPI video frame buffer 4 corresponding to the display screen of the raster scan CRT monitor 7 on a one-to-one basis.

At this time, a display range such as a designated azimuth and a designated altitude is set in the PPI scan conversion circuit 2 by a display area control signal DTCL sent from an operation unit (not shown). It is assumed that drawing can be performed on the CRT monitor 7 based on the read data. The display area control signal DTCL sets the designated azimuth, designated altitude, and the like from the azimuth signal Az, beam number, and radar trigger included in the control signal CTL, and uniquely sets an arbitrary area, thereby preventing external interference. It is possible to control on / off of the video display of the specific area being received. That is, the display area control signal DTCL sets the designated azimuth, the designated altitude below the designated altitude, the designated altitude of an arbitrary width over two or more EL beams, the designated altitude or more, and the like. When the signal is received, the output of the radar video signal in the disturbed area is prohibited, and the PPI display using only the effective EL beam which is not disturbed can be performed.

The data stored in the PPI beam frame buffer 4 is read out as video data PDA2 at the timing of raster scan on the CRT monitor 7, and the combined LUT 6 modulates the luminance of the area of the reflected signal to increase the luminance. In addition, an output signal DA is generated by performing processing for making the display color of the area of the reflection signal different from that of the map portion, the character display portion, or the like, and the PPI display as shown in FIG. At this time, the radar video set in the display range by the display area signal DTCL is displayed, but the radar video in the area not set in the display range is not displayed.

The video memory 1 of the beam numbers 1 to n
Is also input to the ECCM scan conversion circuit 3 at the same time. ECC
The M scan conversion circuit 3 scan-converts the radar video signal transmitted from the three-dimensional radar apparatus from the polar coordinate Rθ coordinate system to the R / EL coordinate system according to the timing control signal CLK, and outputs the ECCM display video. As data EDA1,
It is stored in the ECCM video frame buffer 5. At this time, the process of adding several tens of interpolation scans before and after the one EL scan is performed simultaneously, and the result is stored in the ECCM video frame buffer 5. The data stored in the ECCM video frame buffer 5 is read out as video data EDA2 at the timing of raster scan on the CRT monitor 7, and the combined LUT 6 determines the luminance and display color of the image in the area of the reflected signal and outputs the output signal. DA is generated, and thereby, an ECCM display as shown in FIG. 3 is performed on the CRT monitor 7.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and there are design changes and the like that do not depart from the gist of the present invention. Is also included in the present invention. For example, although the CRT monitor 7 is used to display a radar video image,
Not only the CRT but also a monitor using a liquid crystal display or a monitor using a plasma display can be used. Further, the PPI scan conversion circuit 2 and the ECCM scan conversion circuit 3 may have a hardware configuration or a software configuration. For software configuration, C
PU (Central Processing Unit), ROM (read only memory) storing a conversion program and conversion data, RAM (random access memory) having a work area, an input / output unit, and a CPU bus for connecting these Can be applied.

[0024]

As described above, according to the configuration of the present invention, in the radar video display device of the three-dimensional radar device, when the radio wave is interrupted, the azimuth and altitude range of the disturbed radar video signal are reduced. Is specified, the radar video in the disturbed area is deleted from the PPI display screen and only the undisturbed radar video is displayed. However, PPI display can be performed only with radar video that is not affected by interference. For this reason,
The visibility of the displayed image is improved, and the operator can continue to observe the target. Also, in a radar video display device of a three-dimensional radar device, a video signal based on a reflection signal for an EL beam is subjected to interpolation processing of several tens of lines before and after the EL beam as a center, and ECCM display is performed, thereby causing radio wave interference. In addition to the luminance modulation of the radar video, the area display by the extended display of the video signal is performed, so that the visibility of the displayed image is improved and the target can be identified.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a PPI display mode in the device.

FIG. 3 is a diagram showing an ECCM display mode in the device.

FIG. 4 is a diagram illustrating the concept of a full-circle search of the three-dimensional radar device.

FIG. 5 is a diagram showing an example of a conventional ECCM display.

[Explanation of symbols]

 Reference Signs List 1 video memory 2 PPI scan conversion circuit (PPI scan conversion means) 3 ECCM scan conversion circuit (ECCM scan conversion means) 4 PPI video frame buffer 5 ECCM video frame buffer 6 Synthetic LUT (display conversion means) 7 CRT monitor (display) means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-162280 (JP, A) JP-A-58-778 (JP, A) JP-A-9-211103 (JP, A) JP-A-4- 40386 (JP, A) JP-A-4-283677 (JP, A) JP-A-4-128675 (JP, A) JP-A-63-19577 (JP, A) JP-A-58-193278 (JP, U) (58) Field surveyed (Int.Cl. ⁷ , DB name) G01S ⁷ /00-7/42 G01S 13/00-13/95

Claims (6)

(57) [Claims] 1. A radar video display device for displaying an image of a radar video signal of a three-dimensional radar device which performs scanning in an azimuth direction while repeating scanning in an altitude direction on a display device of a raster scan system, the same as the three-dimensional radar device. The radar video signal of each altitude direction scan for the azimuth is synthesized, and the synthesized radar video signal of the polar coordinate system scan is converted into the radar video signal of the orthogonal coordinate system scan and displayed on the display means. A radar video display device comprising: a PPI scan conversion unit for prohibiting output of the radar video signal to the display unit in an azimuth and altitude range set according to an external command. 2. The method according to claim 1, wherein the setting of the altitude range in the PPI scan converter is performed in accordance with a selection of a specified altitude or less, a specified altitude between arbitrary widths, and a specified altitude or more. 2. The radar video display device according to 1. 3. A display conversion means for performing a luminance modulation or a process of changing a display color on the display means for a region of the reflected signal in the converted rectangular coordinate system radar video signal. 3. The radar video apparatus according to claim 1, wherein: 4. A radar video display apparatus for displaying a radar video signal of a three-dimensional radar apparatus which performs scanning in an azimuth direction while repeating scanning in an altitude direction on first and second display means of a raster scan system, The first display means for synthesizing radar video signals of each three-dimensional scanning in the same azimuth of the three-dimensional radar apparatus and converting the synthesized radar video signal of the polar coordinate system scanning into a rectangular coordinate system scanning radar video signal; And PPI scan conversion means for prohibiting output of the radar video signal to the first display means in an azimuth and altitude range set in accordance with an external command when radio wave interference exists, and The radar video signal of the altitude direction scan of the designated azimuth in the polar coordinate system scan radar video signal of the three-dimensional radar apparatus is converted into a distance / altitude coordinate. It is converted into a system video radar video signal and displayed on the second display means, and the one scanning beam in the altitude scanning is subjected to forward and backward interpolation processing to be displayed on the second display means. A radar video display device comprising ECCM scan conversion means for displaying an area. 5. The ECCM scan conversion means according to claim 1, wherein
5. The radar video display device according to claim 4, wherein the interpolation processing before and after the scanning beams is performed by using several tens of interpolation beams. 6. A display conversion for performing a luminance modulation or a process of changing a display color in the second display means on a region of the reflected signal in the converted radar video signal in the distance / altitude coordinate system. 6. A radar video display device according to claim 4, further comprising means.