JP3711204B2 - Radar equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radar apparatus that displays a track of a target.
[0002]
[Prior art]
In addition to displaying the current radar image, there are radar devices that can display the track of a target along with the radar image. This is because, if such a radar apparatus is used, for example, in the fishing industry, it is advantageous to know the track of other ships and monitor the trends of other ships.
That is, by examining the track of another ship, it is determined whether this ship is currently pulling a net. If a net is being pulled, it is expected that there will be many fish at that point. This is because efficient fishing can be performed by making the ship go to that point.
[0003]
FIG. 3 is a block diagram showing an apparatus configuration for explaining a conventional radar apparatus of this type.
In FIG. 3, 1 is an antenna, 2 is an A / D conversion circuit, 3 is a sweep memory, 4 is a track data processing circuit, 5 is a track video frame memory, 6 is an antenna rotation signal generation circuit, 7 is an angle signal detection circuit, 8 is a coordinate conversion circuit, 9 is a radar image frame memory, 10 is a D / A conversion circuit, 11 is a CRT display, 12 is a transceiver control signal, 13 is a graphic generator, 14 is a graphic frame memory, and 15 is a CPU. is there.
[0004]
The wake data processing circuit 4 inputs the current received data from the sweep memory 3 and outputs the movement amount of the target at each reception timing to the wake image frame memory 5 as wake data from the ship position (this method is relative). This is called a wake memory method, but there is also a true wake memory method in which the amount of movement of a target is memorized in an absolute position regardless of the ship's position).
The wake image frame memory 5 overwrites the wake data input from the wake data processing circuit 4 and outputs the previous data to the wake data processing circuit 4 at the next reception timing. The movement amount of the target is output to the wake image frame memory 5 as wake data.
[0005]
Also, the received data from the sweep memory 3 is input to the radar image frame memory 9, and this data is written at the write address output from the coordinate conversion circuit 8.
The radar image data written in the radar image frame memory 9 and the wake image data stored in the wake image frame memory 5 are converted into analog image signals by the D / A conversion circuit 10, and the radar image and the track are transmitted to the CRT display 11. Overlays the image.
[0006]
The radar apparatus shown in FIG. 3 is configured as described above, and the data is sequentially updated in the radar video frame memory 9, but the stored data is simply overwritten in the wake video frame memory 5 while the wake data is being acquired. The stored data is not erased, and therefore the ship's track is also displayed.
[0007]
[Problems to be solved by the invention]
The conventional radar apparatus as described above has a problem in that the wake of the ship is displayed when the wake is displayed.
In other words, the image of own ship is not the reflected signal of the electromagnetic wave transmitted from the antenna, but is called a main bang where the transmitted signal directly wraps around, or it is a reflected signal reflected by the wave front generated at the stern. However, if the track of this image is displayed together with the track of another target, the display screen becomes complicated and difficult to see, which may cause misrecognition. Become.
[0008]
As a method for preventing such ship's track from being displayed, conventionally, a circuit called main bang suppression is used, and for a short time immediately after transmission , the reception sensitivity is lowered and the image near the ship is erased. However, if this method is used, the image near the ship cannot be written into the radar image frame memory, and the image near the ship is not displayed in the radar image, so that safety in navigation cannot be ensured.
[0009]
The present invention has been made to solve such a problem, and in the display of the track image, the track of the target such as another ship is displayed, but only the current radar image is displayed in the ship and the vicinity of the ship. An object of the present invention is to provide a radar device that performs the above-described operation.
[0010]
[Means for Solving the Problems]
The radar apparatus according to the present invention is a radar apparatus that displays a wake image of a moving target together with (or separately from) a current radar image. A received signal received at a predetermined timing is received from a wake image display memory and a radar image. Input to the display memory, and the wake image display memory obtains information on the wake of the moving target by sequentially overwriting the received signal received at each predetermined timing, and for displaying the radar image. In the memory, means for obtaining the current radar image by sequentially updating the stored contents with the received signal received at each predetermined timing, and provided in the previous stage of the wake image display memory, and at each predetermined timing the reception signals received for a predetermined time to the gate after the transmission termination, and a gate circuit for inputting the received signal to the track video display memory, the radar The image display memory receives a reception signal received at each predetermined timing without going through the gate circuit, and displays a track image of the target in the radar image display by displaying the track near the own device. Then, the wake display in the vicinity of the own device is not performed. Further, the apparatus further comprises means for varying the gate time of the gate circuit.
[0011]
The radar apparatus according to the present invention is configured as described above, so that, for example, when mounted on a ship, the ship's track display can be prevented from being performed without impairing the safety of navigation.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram showing an embodiment of a radar apparatus of the present invention.
In FIG. 1, reference numeral 1 denotes an antenna that transmits and receives electromagnetic waves, 2 denotes an A / D conversion circuit that converts a received signal received by the antenna 1 into a digital signal, and 3 temporarily stores the received signal converted into a digital signal in time series. A sweep memory 16 is a gate signal generation circuit for gating a received signal from the sweep memory 3 at a predetermined timing for a predetermined short time.
The received signal stored in the sweep memory 3 is sent to the gate signal generation circuit 16 and the radar image frame memory 9.
A wake data processing circuit 4 receives a received signal through the gate signal generation circuit 16 and outputs the movement amount of the target at each reception timing to the wake image frame memory 5 as correlation data from the position of the ship.
[0013]
Reference numeral 6 denotes an antenna rotation signal generation circuit for generating a rotation signal synchronized with the rotation of the antenna 1, 7 an angle signal detection circuit for detecting the azimuth of the direction of the antenna based on the rotation signal, and 8 an output from the angle signal detection circuit 7. Is a coordinate conversion circuit that converts the azimuth angle of the antenna to be converted into an XY coordinate signal, and the received signal output from the sweep memory 3 is a radar image frame at the address of the XY coordinate input from the coordinate conversion circuit 8. It is written in the memory 9.
A wake image frame memory 5 overwrites the wake data with the correlation data input from the wake data processing circuit 4 and outputs the previous data to the wake data processing circuit 4 at the next reception timing. In step 4, the movement amount of the new target is sequentially output to the wake image frame memory 5 as correlation data.
[0014]
The radar image data written in the radar image frame memory 9 and the wake image data stored in the wake image frame memory 5 are converted into analog signals by the D / A conversion circuit 10, and the wake image is converted into the radar image by the CRT display 11. Are superimposed and displayed.
Reference numeral 12 denotes a transmitter / receiver control circuit for controlling a transmitter / receiver for transmitting and receiving radar signals provided on the antenna 1. Reference numeral 13 denotes a graphic generator for generating ranges, symbols, characters, etc. necessary for display on the CRT display 11, A graphic frame memory 14 stores generated characters and the like, and a CPU 15 controls the entire apparatus.
[0015]
Next, the operation of the radar apparatus shown in FIG. 1 will be described. As apparent from a comparison between the radar apparatus shown in FIG. 1 and the radar apparatus shown in FIG. 3, in the radar apparatus of this embodiment, a gate signal generation circuit 16 is inserted between the sweep memory 3 and the wake data processing circuit 4. The reception signal from the sweep memory 3 can be gated at a predetermined timing for a predetermined short time. Therefore, the reception signal from the aerial 1 is gated for a predetermined short time after the transmission is completed for each transmission / reception of electromagnetic waves, so that the reception signal from the vicinity of the ship is not input to the wake data processing circuit 4, so the wake image The frame memory 5 does not store the track of the ship, but stores only the track of a target that is a predetermined distance away from the ship.
[0016]
Also, since the current received signal from the sweep memory 3 is input and stored in the radar image frame memory 9 without going through the gate signal generation circuit 16, the vicinity of the ship is properly displayed in the radar image display. And navigational safety is not compromised.
[0017]
That is, as shown in FIG. 2 (X) → (Y) → (Z), this type of conventional radar apparatus displays the track of the ship in addition to the track display of the target. In the radar apparatus according to the embodiment of the present invention shown in FIG. 2, the wake of the target is displayed in the wake image displayed on the CRT display 11 as shown in (A) → (B) → (C) of FIG. However, the ship's track will not be displayed. In (A) → (B) → (C) in FIG. 2, a portion drawn by a dotted line is a portion that suppresses wake data for a predetermined distance from the position of the ship (that is, a predetermined time immediately after transmission ), Although the ship's wake is not drawn, the radar image frame memory 9 is written from the ship's main bang (the black circle on the bow in the figure), and the radar image of the ship and its vicinity is missing. You can see that it is displayed.
[0018]
In the above-described embodiment, the wake image frame memory 5 and the radar image frame memory 9 are separate and independent memories, but may be configured to use different storage locations of one frame memory.
The gate signal generated by the gate signal generation circuit 16 may be always fixed length, or the CPU may set an arbitrary time and suppress the current data for the set time.
In the above description of the embodiment, the radar apparatus is described as being mounted on a ship, but it is needless to say that the present invention can be applied to all radar apparatuses mounted on a moving body such as an aircraft.
Furthermore, although the above-described embodiment has been described as a radar device that displays a wake image of a target together with a radar image, a radar device that displays a wake image and a radar image separately may be used.
[0019]
【The invention's effect】
As described above, the radar device according to the present invention can display the track of the own ship which is not necessary for the track display, so that it is possible to display the track easily and the radar image is displayed up to the vicinity of the ship. Therefore, there is an effect that a user-friendly radar device can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram for explaining an embodiment of a radar apparatus of the present invention.
FIG. 2 is a diagram for explaining the effect of the radar apparatus of the present invention.
FIG. 3 is a block diagram showing an example of a conventional radar apparatus of this type.
[Explanation of symbols]
Reference Signs List 1 antenna 2 A / D conversion circuit 3 sweep memory 4 track data processing circuit 5 track video frame memory 6 antenna rotation signal generation circuit 7 angle signal detection circuit 8 coordinate conversion circuit 9 radar image frame memory 10 D / A conversion circuit 11 CRT display 12 Transmitter / receiver control signal 13 Graphic generator 14 Graphic frame memory 15 CPU
16 Gate signal generation circuit

Claims (2)

In a radar device that displays a wake image of a target that moves with (or individually) the current radar image,
A received signal received at each predetermined timing is input to a wake image display memory and a radar image display memory, and the wake image display memory sequentially overwrites the received signal received at each predetermined timing. In the radar image display memory, the current radar image is obtained by sequentially updating the stored content with the received signal received at each predetermined timing in the radar image display memory.
A gate circuit provided in a preceding stage of the wake image display memory, and gates a reception signal received at each predetermined timing for a predetermined time after the end of transmission, and inputs the reception signal to the wake image display memory. Prepared,
The radar image display memory is inputted with the received signal without going through the gate circuit,
A radar apparatus that displays in the vicinity of its own apparatus in a radar image and does not display a wake in the vicinity of its own apparatus in a track image of a target . The radar apparatus according to claim 1, wherein
2. The radar apparatus according to claim 1, further comprising means for changing a gate time of the gate circuit.

Images