JPS64668B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for displaying radar video, and in particular, it is possible to simultaneously display video from two radars that are synchronized at a certain period, each of which has a different transmission repetition period. It is related to things that have been done in this way.

Conventionally, there is a device shown in FIG. 1 that realizes this type of display, and FIG. 5 shows its PPI display.

In FIG. 1, 1 and 3 are gate circuits that allow video to pass depending on whether or not to display the video;
A control circuit 2 controls the gate circuits 1 and 3 depending on whether or not to display a video, and a display circuit 4 performs a PPI display as shown in FIG. 5 based on the outputs of the gate circuits 1 and 3.

Next, the operation of the circuit will be explained.

The radar triggers (generated at each transmission repetition) shown in FIGS. 2a and 2d are input to input terminals 6 and 7 in FIG. 1, respectively. As you can see, each radar has a different cycle, but they are synchronized at a constant cycle.

Input terminal 5 corresponds to input terminal 6, indicating that the radar video for transmission at the timing of terminal 6 is input to the terminal. The timing of the radar video input to this input terminal 5 is shown in FIG. 2b. Input terminal 8 corresponds to input terminal 7, indicating that it is a terminal to which radar video for transmission at the timing of terminal 7 is input. The radar input to this input terminal 8
The timing of the video is shown in Figure 2e.

The display circuit 4 obtains the display timing from the control circuit 2, but since the display circuit generally operates only at one timing, the control circuit 2 selects either one of the input terminals 6 and 7 to display the display. Supplied to circuit 4. In the description here, it is assumed that the timing of the input terminal 7 is used.

The display circuit 4 is operating at timing d in FIG. Since the timing in FIG. 2e is synchronized with timing d, it can be displayed as is. Therefore, the control circuit 2 controls the gate circuit 3 so that the light passes through the gate circuit 3 as is. On the other hand, the timing in FIG. 2b is synchronized with timing a, and can be synchronized with timing d only when timings a and d are synchronized. Therefore, when displaying with a display circuit, the correct distance can be displayed only when this synchronization is achieved, and the correct distance cannot be displayed for other out-of-synchronization radar videos.

As a result of the above, the input video shown in FIG. 2b must be displayed only when timings a and d are synchronized. Therefore, the control circuit 2 controls the gate circuit 1 to allow the radar to pass only when timings a and d are synchronized, and as a result, the radar that has passed
The video will look like Figure 2c. FIG. 5 shows how these two radar videos e and c are displayed on the display circuit 4.

Although FIG. 5 shows an example of two radars synchronized with a timing (repetition period of the radar) of 2:3, the same can generally be said of radars with a timing of m:n.

In the conventional radar video simultaneous display method shown in Figure 1, all the radar videos that are synchronized with the display timing are displayed, but the synchronization with the display timing is at one point. There was a drawback that the radar video of a radar that could be synchronized but not others was displayed only when synchronized and not at other times.

This invention was made in order to eliminate the problems of the conventional ones as described above, and it is also possible to synchronize the radar video of a radar that can synchronize at one point with the display timing but not at other points. The object of the present invention is to obtain a simultaneous radar/video display device capable of displaying images with or without radar.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 3 shows a simultaneous display device for radar and video signals according to an embodiment of the present invention, in which 1
4, 15, 16, and 37 are radar videos of two radars that are synchronized with each other with a transmission repetition period of n:m, and have a timing (transmission repetition) that is not used for display. This is a memory circuit for storing data. Hereinafter, for the purpose of explanation, it is assumed that n is the timing used for display, and m is the timing not used for display. The figure shows an example where m is 4. 31 is a memory circuit 14, 15, 16, 37
A control circuit stores the radar video at timing m and outputs the stored radar video at timing n; 17 is a storage circuit 14, 15, 1;
An adder circuit that adds the outputs of 6 and 37 to form one video, and 18 is the output of the adder circuit 17, which has become one, that is, a radar at timing m synchronized with timing n (timing for display).・This is a display circuit that displays video and radar video at timing n as shown in FIG.

Next, the operation of one embodiment of the present invention will be described.

The radar trigger shown in FIG. 4 a (occurs every time the transmission is repeated) is input to the input terminal 21 shown in FIG.
The radar trigger shown in FIG. 4b is input to the input terminal 22 shown in the figure. As you can see, the two radars have different cycles, but are synchronized at a constant cycle. A case where synchronization is achieved at a ratio of 3:4 will be described below as an example.

Input terminal 19 corresponds to input terminal 21,
The timing of terminal 21 indicates that this is the terminal to which radar video for transmission is input.

This example uses FIG. 4a (timing of input to the input terminal 21) as the timing for displaying in the display circuit 18. By doing so, the radar video input to the input terminal 19 is supplied as is to the display circuit 18, and is displayed without being lost.

On the other hand, the input terminal 20 corresponds to the input terminal 22, indicating that the radar video for transmission at the timing of the terminal 22 is input to the terminal.

The radar video input to this input terminal 20 is divided into 32, 33, 34, and 38 as shown in FIG. 4b according to its transmission repetition period. Each of these is stored once in a memory circuit, and its contents are saved. That is, the radar videos 32, 33, 34, and 38 are stored in the storage circuits 14, 15, 16, and 37, respectively. The memorized time is the fourth
Shown in Figures c, e, g, and i.

The control circuit 31 uses the timing of the input terminals 21 and 22, and uses the timing of the input terminal 22 as a base to determine the timing for storing each of the storage circuits,
It is controlled by creating gates and supplying them to each memory circuit.

Here, the stored video input to the input terminal 20 must be read out for display. Naturally, the reading must be performed in synchronization with the timing shown in FIG. Furthermore, it is necessary to read the data at a time that does not include the time during which it is stored, so as not to damage the contents by reading it while it is being stored.

To explain with FIG. 4b, timing 32, 3
The radar video stored in 3, 34, and 38 is 3.
6, 39, 35, and 35, respectively. This relationship is shown in FIGS. 4e-j. This allows input terminal 2
Radar video input to 0 is fed to display circuit 18 without loss of its content. In terms of memory circuits, the memory circuits 14, 15, 16, and 37 read and output their respective memories using radar videos 36, 39, 35, and 35.

The control circuit 31 uses the timing of the input terminals 21 and 22, and uses the timing of the input terminal 21 as a base to determine the timing for reading each of the storage circuits,
It is controlled by creating gates and supplying them to each memory circuit.

As can be seen from the fact that there is only one input to the input terminal 20, the outputs of the memory circuits 14, 15, 16, and 37 are added together in the adder circuit 17 in order to supply one radar video to the display circuit 18. and combine them into one.

With this configuration, even radar video that is synchronized with transmission repetitions that are not used as display triggers (transmission repetitions) can be displayed without losing its contents.

In the above embodiment, the outputs of the memory circuits are combined into one video by adding them in the adder circuit 17, but instead of the adder circuit 17, a circuit that takes the maximum value or a circuit that adds and takes the maximum value is used. The combinational circuit may be provided at the same location, and the same effects as in the above embodiment can be obtained.

Furthermore, in the above embodiment, a radar with two transmission repetitions synchronized at 3:4 was explained, but the repetition period is not limited to 3:4, and is generally applicable to radars synchronized at n:m. can do. However, the condition is that the storage time and readout time do not overlap.

Furthermore, although the above embodiment describes two radars, the present invention can also be applied to two or more radars, and by doing the above, the content of radar videos of a plurality of radars will not be damaged. It is possible to perform display without

As described above, according to the radar video signal synchronization display device according to the present invention, the radar video signal synchronized with the timing that is not synchronized with the display timing can be displayed using the storage circuit. Since the video is converted into a video that is synchronized with the timing, there is an effect that all the radar videos can be displayed simultaneously.

[Brief explanation of drawings]

FIG. 1 is a block diagram illustrating a conventional simultaneous display system for radar and video signals, FIG. 2 is a timing diagram illustrating the simultaneous display system shown in FIG. 1, and FIG. 3 is a block diagram illustrating an embodiment of the present invention. Fig. 4 is a timing diagram explaining the simultaneous display method of Fig. 3, Fig. 5 is a diagram showing a display example based on the method of Fig. 1, and Fig. 6 is a diagram showing a display example based on the method of Fig. 3. FIG. In the figure, 14, 15, 16, and 37 are storage circuits, 17 is an addition circuit, 18 is a display circuit, and 31 is a control circuit.

Claims (1)

[Claims] 1. In a device for simultaneously displaying radar videos of at least two radars synchronized with each other with transmission repetition periods m:n, comprising: m storage circuits that store video in correspondence with each of the transmission repetition periods m; and a control circuit that controls the storage circuits to store video at the transmission repetition period m and to read it at the transmission repetition period n. , an adder circuit that adds the outputs of the m memory circuits, and a radar video with a transmission repetition period n that is input directly from the outside and the video output from the addition circuit, which corresponds to the transmission repetition period n. 1. A simultaneous display device for radar and video signals, comprising: a display circuit for displaying video.