JPS58198775A - Display device of sonar - Google Patents

Abstract

PURPOSE:To facilitate the discrimination of a detected object, by selecting detection signals from plural directions out of detection signals from widerange directions and displaying respective courses with the passage of time simultaneously on a display. CONSTITUTION:Detection signals from three continuous directions (n), n+1, and n+2 are displayed continuously and stereoscopically on a display screen with contraction scales slightly different from one another in the (x) direction. Schools of fish G1, G2, and G3 are displayed by detection signals from three directions. When pictures G1, G2, and G3 overlap, the picture G1 concerning the direction (n) is first preferred, and the picture G2 concerning the direction n+1 is next preferred.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an underwater detection device such as a searchlight sonar or a scanning sonar that detects a wide range of directions, and particularly relates to a display device that displays the time course of detection signals returning from a wide range of directions. .

Conventional underwater detection devices of this kind, for example, transmit omnidirectional ultrasonic pulses in a wide range of directions, while the reflected waves returning from each direction have individual directional directions for each direction. The waves are received by an ultrasonic receiver. When the reflected waves returning from each direction are displayed on a cathode ray tube of a display device, it is necessary to time-series each reflected wave at high speed, so the reflected waves on the equidistant line are sampled, and the sampling signal is Alternatively, the electron beam of a cathode ray tube that performs spiral scanning is brightly modulated, and the reflected waves from each direction are displayed at each corresponding azimuth position.

However, in such display devices, reflected waves are often displayed in a mosaic pattern on the cathode ray tube due to the directivity of the ultrasonic receiver. In addition, the reflected waves returning from the water are relatively unstable due to the movement of the ship, so it is relatively difficult to distinguish on the display whether noise is being displayed or a detected object is being displayed. It is. In particular, when the detected object is a small object, the detected object is displayed as a dot on the display, and is displayed blinking depending on the movement of the ship, etc., making it even more difficult to identify the detected object.

However, with such a display device, the detected object is displayed moment by moment, and the movement of the detected object over time is based on the operator's memory of the detected object's past movements. There is a difficulty in accurately grasping the continuous movement of the detected object.

In view of the above, it is an object of the present invention to display detection results in a wide range of directions on a display, and to select reflected waves (detection signals) returning from a desired range of directions, y, = time of detection signal. By separately providing the same display and displaying it on one display, the presence or absence of a detected object can be clearly identified, and the movement of the detected object can be accurately and easily monitored. It is an object of the present invention to provide a display device in an underwater detection device that can be grasped.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

In addition, in the present invention, by superimposing the time course of detection signals from multiple consecutive directions on the display, the time course of detection signals from multiple directions can be displayed simultaneously. At the same time, relationships with adjacent directions can be displayed in an easy-to-understand manner and three-dimensionally.

First, in the present invention, by storing the time course of detection signals in all directions in a memory, detection signals in any direction can be displayed at any time.

First, before proceeding to a detailed explanation of the embodiments of the present invention, a method of displaying detection signals in the present invention will be briefly explained with reference to FIG.

FIG. 1 is a diagram showing a display example in which detection signals received by a scanning sonar and from eight consecutive directions are superimposed on a display. In the display screen of the display device in FIG. 1, the X direction indicates the depth direction, and the Y direction indicates the time direction. The eight consecutive directions are respectively coded n, n+'l,
It is n+2. Now, if the display range is 100m deep, there is a detection signal from the n direction. Next, (n+1
') The detection signal from the direction is displayed from the upper end of the display screen in the X direction to Xi as 0 to 100 m. The image scale factor in this case is 1-a. 1 kodashi, 0 < a
< 1. Similarly, the detection signal from the (n+2) direction is from 0 to x2 from the top of the display screen in the X direction.
Displayed as 100m. In this case, the image scale rate is 1
-2a. In this way, consecutive detection signals from around 80,000 can be displayed continuously and three-dimensionally on the display screen at slightly different scales in the X direction. Here, Gl, G2, and G3 are schools of fish displayed by detection signals from eight directions. In the above display example, the detection signals from each direction are displayed at slightly different scales, and the position of the oscillation line system is the same for all detection signals. In this case, the scale factor may be kept constant and the position of the oscillation line system may be shifted little by little in response to each detection signal. Furthermore, although the display screens for each detection signal in the above display example have different sizes within equal distances corresponding to the respective image scales, they may also have different sizes geometrically. .

In the above display example, when images G1 + G2 * G3 based on detection signals from 30,000 positions overlap, the image Gl related to the n direction is given top priority as shown in the figure, and the image Gl is given the next priority. Image G2 regarding the (n+1) direction is first displayed. Next, the detection signals from the 80,000th place are superimposed on each other at slightly different scales with the above priority order. For example, on the ocean floor, the seabed from the 30,000th place is continuously displayed. Is, ', & are displayed overlappingly, and therefore it is very difficult to separate the submarine line (14+13) in the n direction and the Cn+1) direction.Therefore, the display signals on the display screen corresponding to the detection signals in each direction are The surrounding area is surrounded by a single color predetermined for each direction, and the detection signals including that color are superimposed and displayed in the priority order.In this case, as described above, the entire surrounding area of the display signal is Instead of surrounding the seabed with a specific color, it is possible to obtain an easy-to-understand display by surrounding only the top of the seabed with a specific color. This embodiment is applied to a scanning sonar and will be described with reference to FIGS. 2 to 4.

FIG. 2 is a schematic diagram of the display screen in this embodiment. That is, the display screen of this embodiment has L pixels of 0.1 in the Y direction.
..., M pixels 0.1 in the L-1 and X directions. ...2
Consists of M-1. However, in this embodiment, the entire 360° circumference of the scanning sonar is divided into N directions, and the detection signals from the N directions are written into the memory for L times of transmission, while the detection signals are read out from the memory. In principle, as shown in the above-mentioned display example, the detection signals from each direction are superimposed and displayed on the display screen by performing a display operation using circuit means, which will be described in detail later.

FIG. 8 is a block circuit diagram of this embodiment.

In this example, for convenience of explanation, the following conditions are specified. That is, (1) the direction of overlapping is up to 8, (2) only the upper side of the detected signal shall be surrounded by a specific color, and (3) the detected object is displayed on a separate display from the display that displays each moment. (4) The display shall be a color cathode ray tube.

Note that the symbols assigned to each component are not necessarily assigned in the order of explanation.

First, in FIG. 8, the ultrasonic transducer 1 transmits ultrasonic pulses in a wide range of directions and receives reflected waves from various directions in the water. Here, the ultrasonic transducer 1 is
As shown in FIG. 4, the pointing direction is θ. , θl+02+・
..., θNl, the directional transducers m+T1+T2+...sTN-1 are arranged along the circumferential direction. In the ultrasonic transducer 1 having such a configuration, when transmitting ultrasonic pulses, the transmitter 2 transmits all the directional transducers To +''r1.m.

...e TN-1 is simultaneously excited to transmit ultrasonic pulses in a wide range of directions. The reflected waves transmitted in this way and returning from each direction are transmitted to the directional transducer To, 'r1°T2. ...r Received by TN-1. The received T co-reflected wave is sent to the time series circuit 3. The time-series circuit 3 electronically switches and time-series the detection signals related to the reflected waves that have been sent out.For example, as shown in FIG. To
, T1+T21...*Fixed terminals So, Sl, S2., which individually correspond to TN-1. ...+5N-1. □ Fixed terminal So IsI of time series circuit 8, S
21...+5N-1 directional transducers TO, T1 . T2...

Each detection signal from T N-1 is transmitted from the movable terminal Soo to each of the fixed terminals So, Sl, S2,...e5N-
1, they are sequentially taken out.

The switching operation of the movable terminal Soo of the time series circuit 8 is performed by the count output from the azimuth counter 7.

The azimuth counter 7 is an N-ary counter that counts the +f pulse train sent from the frequency divider 8, and counts the pulse train of the divider 8 from 0 to N-1,
is a directional transducer 1. r1+T2 v...

Each detection signal from TN-1 is sent out once to the converter 4, and when the count value changes from N-1 to 0, a depth pulse is generated and the depth pulse is sent to the depth counter 6.
Send to. Note that the time series circuit 8 connects the directional transducers To, T1 .
Ts , ..., the detection signal from T1 is converted into ~X converter 4
Send to.

Next, the depth counter 6 is an M-ary counter and counts the depth pulses from the azimuth counter 7 from O to M-1, until the count becomes 0 at the next M-th depth pulse and T
At this time, a time pulse is generated and sent to the time counter 5 and the transmission circuit 2. The transmitting circuit 2 drives the ultrasonic transducer 1 using this time pulse. On the other hand, the time counter 5 is an L-adic subtraction counter,
L-1, L-2° with time pulse from depth counter 6
..., decrement the count to 2, 1.0, and go low at the next time pulse.
Returns to the count value of -1.

The respective values of the azimuth counter 7, depth counter 6, and time counter 5 are used as detection signal write address signals of the memory circuit 57, which will be described later.

Note that the frequency divider 8 divides the frequency of the output clock pulse (frequency fo) of the clock pulse circuit 18 according to the setting value of the detection range setting device 9. For example, the detection distance is 500
Assuming that the speed of sound in water is 1500 m,
The output pulse frequency of the splitter 8 is given by the following equation.

A: / 500J Ru.

Next, the memory circuit 57 will be explained with reference to FIG. This memory circuit 57 has islands for each direction.

θ1. θ2. ..., (N-1
) memories 571.572. ..., 57(N-
1) exists. Each memory 571.572.・・・
, 57(N-1) is the number of pixels in the Y (time) direction in FIG. 2 x the number M of pixels in the X direction (depth) direction x I
It has a storage capacity of bits.

Well, each memory 571.572. ..., 5
7(N-1) is a 1-bit input line Di and an output line Do.
i (i=0.1 + - + N-1), an α-bit address line, a 1-bit write/continue line, and a 1-bit selection line. Note that the value of a above is β when L-1 and M-1 are expressed as binary numbers, respectively.
The number of bits and the number of β bits, in which case α=β+ν
The formula holds true. Similarly, ρ is the number of bits per unit, where N-1 is expressed as a binary number.

Next, from the NΦ converter 4 to each of the memories 571, 572 . ..., I to 57(N-1)
A bit detection signal is input via input line Di.

Each count output of the depth counter 6 and time counter 5 is
Each memory 571, 572 via the switch 40.41
, . . , 57 (N-1), the address at which the detection signal is written into the memory is designated.

First, the count output of the direction counter 7 is sent to the decoder 45.
By inputting the decoded signal to each memory, the memory in which the detection signal is written is specified.

On the other hand, among the detection signals from each direction written in the memo IJ-571 etc. in correspondence with time, depth and direction, only the detection signal from the 80,000 position is detected by the changeover switches 17, 18, 19, 42, 48, and 44, it is read out from the memory circuit 67.

Here, the changeover switch 19 is the changeover switch 1 in the n direction.
8 is in (n+1) direction, changeover switch 17 is in (n+2) direction
Select memory output data for direction. Further, the changeover switch 42 is at position n73', and the changeover switch 48 is at position (n+1).
) direction, the changeover switch 44 switches the depth direction address among the read addresses of the (n+2) direction. Furthermore, in these memories, the time direction address among the read addresses is read out by the adder 10, and the time direction address in the read address is read out by the adder 10, and
5 operates to select all memories during reading, and the detection signal of the selected memory location is read out.

Memory 571, 572. ..., the write/read timing control of the detection signal in 57(n-1) is a clock pulse! This is done by the output pulses of generator 13.

Frequency f of the output pulses of clock pulse generator 18.

is the frequency at which the display detection signal is transferred to the display device 50. When the first output pulse of the clock pulse generator is high, a write is performed to the memory, and when the first output pulse is low, a read is performed from the memory. The switches 40, 41 and decoder 45 also operate simultaneously in response to this writing/reading, and when the output pulse is at a high level, the changeover switch switches to the left contact in the diagram, and the output pulse When the level is low, it switches to the right contact.

Furthermore, when the output pulse is at a high level, the decoder 45 operates only the memory corresponding to the value obtained by decoding the count value of the azimuth counter 7, while when the output pulse is at a low level, it operates all the memories. make it work.

Since the output frequency of the clock pulse generator 18 is higher than the output frequency of the branch divider 8, the detection signal will be written to the same memory location many times in succession. The detection signal immediately before the count value changes will be stored. In addition, the switching device 42,
The reason why the depth direction addresses in eight directions are switched in 48.44 is that the scale factors in each direction are different as described above.

Next, if the count value of the depth direction reading counter 15 indicating the read address in the depth direction is X, the count value for the n direction is X, and the count value for the (n+1) direction is xAl- a) and (n+2
) direction, its count value must be x/(1-2a). The read-only memories 11 and 12 are the first memories, and one read-only memory 11 calculates x/(' 1-2a) for input X, and the other read-only memory 12 calculates x/(' 1-2a) for input X. x/(1-a
), respectively. Note that a multiplier may be used instead of this read-only memory.

The depth direction reading counter 15 and the time direction reading counter 14 indicating the time direction read address will be explained. First, the depth reading counter 15 is an M-ary counter, which counts the clock pulses of the clock pulse generator 18 from 0 to (M-1), and when the next pulse reaches 0, the reading counter 15 reads out the clock pulses in the time direction. The pulse for successive output is sent to the counter 14 for reading in the time direction. The time direction readout counter 14 is an L-adic counter, which counts the time direction readout pulses from the depth direction readout columns 15 from 0 to M, and counts when the next time direction readout pulse is input. The value becomes 0. Depth direction reading counter 15
The adder 16 adds 1 to the count value of the shift register 28, 24. This is the first step to advance in order to avoid this.

When the first addition value of the adder is M, the adder 16 outputs 0.

Next, the detection signals from eight directions of one bit per bit read out from the memory are sent to adders 20, 21 and 2z through switchers 17, 18 and 19. Adder 20.21
．． Strictly speaking, 22 is a subtracter, and there are too many weak signals in the n direction in the detection signal, and (n+1) and (n+
2) It is a T-type that cancels out the weak signal in the direction detection signal once it becomes invisible. Adder 2
When subtracted by 0, 21.22 and becomes 0 or negative, O is output to the shift registers 2B and 24.25, respectively. Here, setting outputs of the same value are sent from the display signal strength setter 58 to the adders 20, 21, and 22, but a separate display signal strength setter is provided for each direction, and a separate display signal strength setter is provided for each direction. The subtraction value may be changed accordingly.

The shift registers 28, 24, 25 are shift registers for two pixels, and operate together with the corresponding detectors 26, 27, 28 and switchers 29, 80, 81 to color the upper end of the display signal. In addition, each shift register 28
At 24 and 25, display detection signals are acquired in response to the pulses of the clock pulse generator 18 at the same speed as the readout. The two display detection signals captured in this manner are assumed to be Dt and Dt+1. On the display 50, one display detection signal No. 1 Dt is displayed on the upper side. Note that the above coloring is performed when one display detection signal Dt is 0 and the other display detection signal Dt+1 is other than 0. That is, one detection signal Dt is 0 and the other detection signal Dt+1.
The detectors 26, 27 and 28 detect that the value is other than O. The switch 29, 80.81 displays one of the display detection signals Dt, that is, (n direction), P (n+1 direction), and C (n+2 direction) in a predetermined specific color without outputting 0. The data of A, B, and C are output as shown below.

The switch 82.88 is configured such that when overlapping display of 30,000 positions is performed, the detection signal in the n direction is set to (n+1°) and (n
+2) When the direction detection signal is difficult to understand, the display is turned off and the display is turned off.

Note that the display orientation is selected by the display orientation setter 54 and adders 55 and 56. n on the display direction setting device 54.
is set, adders 55 and 56 each add 1+1
, outputs setting signals for each of n+2 directions. n.

n+1. The setting signal for each direction of n+2 is set by the changeover switch 17.
．． IB, 1g, and 42, 48.44, and the switching positions of these switches are set to positions corresponding to the setting signals.

For example, if you want to display only the (n+1) direction in each of the directions n + n + l r n +2, set the setting signal for the (n+1) direction in the display direction setting device 54,
It is advisable to open the switches 82 and 88. With the adder 55°5, it is not necessary to add 1, but a plus.

It can be any negative integer.

The T display signal passing through the switch 29, 80, 81 is input to the read-only memory 49 for priority and color conversion.

This read-only memory 49 prioritizes display in the order of n+n+1 and n+2 among display signals from three directions. That is, the signal in the (n+1) direction is displayed only when the signal in the n direction is 0, and the signal in the (n+2) direction is displayed only when the signals in the n direction and the (n+1) direction are both 0. These signals are then prioritized for display and further converted into separate digital signals that are displayed in a predetermined color corresponding to the signal strength, and then red ( R), green (G).

The light is led to the luminance terminal of the display 50 through D/A converters 84.8j, 86 and amplifiers 37°88.89 for each color of blue 03).

Note that the adder 10 is a circuit for displaying the latest detection signal of the fco written in the memory circuit 57 on the right end of the display 50, and is used when the count value of the time counter 5 is 1, for example.
If it is 0, note! ] -Memo from 571! J-
The 10th memory in the time direction of each memory up to 57 (, N-1) is displayed on the right end of the display 50. Adder 10 Hama 1
When the added value exceeds L-1, the added value is subtracted and the value of 1 is output.

As explained above, according to the present invention, the detection results in a wide range of directions are displayed on the display, and the reflected waves (detection signals) returning from the desired range direction are selected and selected, y,=
Since the time course of the detection signal is superimposed on the display, the detected object is displayed in a mosaic pattern, making it difficult to distinguish it from noise, or when the object is small. The detected object can be clearly identified without being displayed blinking due to a ship's spider, rocking, etc., and in particular, the movement of the detected object can be accurately and accurately identified without relying on the operator's memory. Excellent effects such as easy understanding can be achieved.

[Brief explanation of drawings]

The figures show one embodiment of the present invention. Fig. 1 is a schematic diagram of a display screen for explaining an example of display of a detection signal, and Fig. 2 shows the depth (2) direction and time of the display screen. ization,. (To) A schematic diagram of the display screen for explaining pixels related to the direction, Figure 8 is the overall block circuit diagram, Figure 4 is a specific configuration diagram of the ultrasonic transducer and time series circuit, and Figure 5 is FIG. 3 is a detailed diagram of a memory circuit within the block circuit. 1... Ultrasonic transducer, 2... Transmission circuit, 8...
Time series circuit, 5... Time counter, 6... Depth counter, 7... Direction counter 1. ．． 8... Frequency divider, 9
...Detection range setter, 10...Adder, 11.1
2... Read only memory, '13... Clock pulse generator, 14... Counter for reading in time direction, 15... Counter for reading in depth direction, 16... Adder, 17, 18, 19 ,29,80,81,40.41
...Switcher, 28°24, 25...Shift register, 49...Priority and color conversion read-only memory, 5
o...Display device, 54...Display direction setting device, 57...
・Memory circuit patent applicant Furuno Electric Co., Ltd. Patent attorney Oka 1) Kazuhide Figure 1 Figure 2 Y 1-1.

Claims (1)

[Claims] A display device for an underwater detection device that displays detection signals from a wide range of directions, comprising means for selecting detection signals from a plurality of directions from among the detection signals, and detection signals from one or more directions selected by the selection means. A display device for an underwater detection device, characterized in that it includes means for simultaneously superimposing the time course of each of the signals on a display device.