JPH0153433B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a PPI type sonar that detects a predetermined underwater vertical cross section by sequentially changing the pointing direction in a scanning manner, and displays a specific pointing direction on the cross section together with the cross section image on the display. This invention relates to an underwater detection display device that has a simultaneous display function that displays images from the past over time.

Examples of the present invention will be described below.

In FIG. 1, numeral 1 is a transmitter that repeatedly sends out transmission pulses. Transmission pulses from the transmitter 1 are guided to a transducer 3 via a switch 2. The transducer 3 transmits an ultrasonic pulse into the water every time a transmission pulse is applied.

As shown in FIG. 2, the ultrasonic transducer 3 includes a plurality of transducers, for example, five transducers 3A to 3E.
are arranged in an arc. Vibrator 3A to 3E
The transmission pulses of the transmitter 1 are guided through the respective switches 2A to 2E, and therefore the transmission pulses of the transmitter 1 are guided through the respective switches 2A to 2E.
A to 3E are simultaneously excited and transmit ultrasonic pulses into the water.

Since the oscillators 3A to 3E are excited at the same time,
The transmission range angle of the ultrasonic pulse is from transducer 3A to 3E.
It is possible to set it arbitrarily by appropriately setting the arrangement angle of . The transmission range angle of the ultrasonic pulse is determined by the detection range angle at which the ultrasonic transducer 3 performs underwater detection, and the detection range angle is relatively small compared to the total detection range angle. , for example, set to 30°. Therefore, the vibrators 3A to 3
The arrangement angle of E is set such that the transmission range angle of the transmission pulse includes at least the detection range angle.

Each received signal of the transducers 3A to 3E is transmitted through the switch 2A.
The data is led to the time series circuit 4 through each of 2E to 2E.
The time-series circuit 4 time-series the received signals in each direction and sends them out in a time-series manner.It synthesizes the phases of the received signals from the transducers 3A to 3E and transmits them in a specific direction within the transmitting range angle of the transducer 3. A receiving beam with directivity is formed, and the directivity direction of the receiving beam is changed at high speed within the transmitting range angle. The receiving beam direction is determined by each transducer 3A.
By suitably adjusting the phase relationship of each of the received signals of 3E and combining them, it is possible to form a received beam having directivity in a specific direction according to the phase relationship of each received signal, as is well known. Then, by changing the phase of each received signal, the pointing direction can be changed to another direction. The phase change of the received signal can be controlled by controlling the amount of delay or phase shift using a delay circuit or a phase shifter. The amount of delay or phase shift can be controlled using, for example, a known analog delay circuit in which an input signal is delayed in accordance with a control voltage.

In addition, the direction control of the received beam is controlled by each transducer 3.
The receiving signals A to 3E are appropriately combined to generate multiple receiving beams with slightly different pointing directions within the transmitting range angle of the transmitting pulse, and the receiving signals in each direction are switched at high speed. It may also be controlled.

The above-mentioned time-series operation of the time-series circuit 4 is performed based on the azimuth counter 5 (FIG. 1). The azimuth counter 5 counts the clock pulse train of the clock pulse source 6, and starts counting when the transmitter 1 sends out a transmission pulse and makes the gate 7 conductive. The azimuth counter 5 sequentially and repeatedly designates the pointing direction of the receiving beam taken out from the transducer 3 based on the counted value. That is, the time series circuit 4 transmits the received beam in the direction corresponding to the count value of the direction counter 5 while switching the received beam. The switching speed at which the time series circuit 4 switches the received signals in each direction in one cycle is determined by the counting speed of the azimuth counter 5, and therefore the pulses of the clock pulse source 6, so that the received signals on approximately equidistant lines are transmitted. The cycle is set.

The azimuth counter 5 counts the clock pulses from the clock pulse source 6 and sends an output pulse to the distance counter 8 every time the direction of arrival of the received beam is specified, and resets its own count value. The distance counter 8 counts the distance from the transducer 3 to the reflector, and when it counts, for example, n output pulses from the azimuth counter 5, it sends out an output pulse to shut off the gate 7 and calculates its own count value. Reset. Therefore, since the time series circuit 4 sequentially sends out the reflected waves that return within the time period after the ultrasonic pulse is sent and until the output pulse is sent out from the distance counter 8, The detection distance of the transducer 3 is determined.

As is clear from the above, the azimuth counter 5 specifies the azimuth of the received beam arriving at the transducer 3,
A distance counter 8 specifies the distance to the reflection source.
Therefore, the count values of the azimuth counter 5 and the distance counter 8 are expressed as (γ·φ). The above (γ·φ) is sent to the coordinate converter 9 and converted to a position (x·y) on the XY orthogonal coordinates. Further, the coordinate converter 9 uses the detection output of the detector 10 when performing the coordinate conversion. The detector 10 detects the rotation direction of the transducer 3. The transducer 3 is a rotating motor 11
The direction of transmission and reception of the ultrasonic pulse is rotated by this.

In FIG. 3, α indicates the direction in which the transducer 3 transmits and receives ultrasonic pulses with respect to the reference direction, and the transducer 3 transmits and receives ultrasonic pulses in an angular range of ±β with respect to the angle α. The detector 10 detects the azimuth angle α and sends it to the coordinate converter 9. The coordinate converter 9 converts the azimuth α from the detector 10 and the transducer 3
Based on the ultrasonic pulse transmission/reception range angle 2β and the azimuth angle θ from the azimuth counter 5, the azimuth φ of the detected object P with respect to the reference azimuth is calculated as φ=(α−β+θ). Then, based on this azimuth angle φ and the distance γ to the detected object P, calculate the following equations: x=n−γcosφ=n−γcos(α−β+θ) y=γsinφ=γsin(α−β+θ) Convert to position (x・y).

Now, the rotation motor 11 rotates the transducer 3 within the range angle set by the range angle setting device 13 based on the control circuit 12. That is, when the full detection range angle is set in the range setter 13, the control circuit 12 drives the rotating motor 11 to rotate the transducer 3 back and forth between the full detection range angles. The control circuit 12 drives the rotary motor 11 every time an output pulse is sent from the distance counter 8. Furthermore, due to the drive, the transducer 3
The rotation angle per rotation is set to the ultrasonic pulse transmission/reception range angle 2β or less than 2β. Therefore, the transducer 3 intermittently rotates by the above-mentioned angle each time an output pulse is sent out from the distance counter 8, and the rotation angle is detected by the detector 10.

After the coordinate converter 9 performs the coordinate conversion as described above, the converted position is sent to the storage circuit 15 via the address switch 14. The memory circuit 15 has a memory capacity of at least n (rows) x 2n (columns), and the time series signal sent from the time series circuit 4 is digitized by the A-D conversion circuit 16 and specified by the coordinate converter 9. Store in memory address. 17 indicates the specific direction (now,
18 is an arithmetic circuit that calculates the detection azimuth angle φ (=α-β+θ). Reference numeral 19 denotes a comparator circuit which sends a matching pulse only during the period in which the detected azimuth angle φ of the arithmetic circuit 18 and the set value φ' of the azimuth setter 17 match. Therefore, this coincident pulse is generated in a certain wave transmission/reception direction α (currently, the wave transmission/reception direction including the above-mentioned set azimuth φ' is α') while the transducer 3 detects once within the entire detection range angle. 1
n pieces are transmitted consecutively within the receiving period based on the number of transmissions. Reference numeral 20 denotes a gate that is conductive only during the sending period of the coincidence pulse and allows the digitized detection signal from the specific direction φ' from the A/D conversion circuit 16 to pass through. At this time, the gate 20 is intermittently conductive,
The blocking operation is repeated n times to extract only the detection signal in the specific direction φ' from among the received signals in the transmitting/receiving direction α', for example, every 1(m) from 1(m) to n(m). This detection signal is then written into the memory circuit 21. The memory circuit 21 has a memory capacity of n (rows) x i (columns), and the addresses in the column direction are not 1 to i but 2n+1 to 2n due to the relationship with the memory circuit 15.
+i. The above writing is as described below.
The extracted signals are written at n addresses in the row direction, and the write operation in the column direction is equal to the cycle of one detection of the entire detection range angle.

Reference numeral 22 denotes a flip-flop (hereinafter referred to as F.F) which changes to a high level at the time of generation of the coincidence pulse, that is, at the time of rising, and is changed to a low level by the output pulse from the distance counter 8. Reference numeral 23 denotes a subtraction counter with a counting capacity i that performs a subtraction count at the rise of the output level from the F·F 22, and the counted value is added by 2n in the next stage addition circuit 24 and sent out. Then, this sending value is led to the address switch 26 via the gate 25 to designate the column address at the time of writing into the memory circuit 21, and at the same time, the output count value of the distance counter 8 is also led to the address switch 26 via the gate 25. 26 to specify the row address at the time of writing. In this way, the extracted detection signal is written to a predetermined storage address. Incidentally, the distance counter 8 and the addition circuit 24 send out a count value every time a wave is transmitted or received, so that all detection write signals in the specific direction φ' are erased when the gate 20 detects no signal. Therefore, the gate 25 is closed and address specification is prohibited except during extraction.

Next, reading of the storage contents of the storage circuits 15 and 21 will be explained. 27 is a reference clock pulse source for memory reading; 28 is a row counter with a counting capacity n that counts the clock pulses and sends the counted value to address switchers 14 and 26; Further, the row counter 28 sends out an output pulse each time the count value is reset from n to 0, and the output pulse is sent to the column counter 29. The column counter 29 counts the output pulses and guides them to the address switch 14 and also to the adder circuit 3.
Lead to 0. The adder circuit 30 adds the output value of the adder circuit 24, that is, the most recently designated write column address, and the addition result value is sent to the address switch 2.
Leads to 6. Therefore, with this readout column address,
The stored contents of each column are sequentially read from the latest specified column in the direction of the oldest column. In this case, the column counter 29 has a counting capacity of 2n+i, and when the count value is 1 to 2n, the stored content is read out from the storage circuit 15, and when the counted value is 2n+1 to 2n+i, the stored content is read out from the storage circuit 21. And each memory circuit 1
The stored contents read out from 5 and 21 are led to a CRT display 32 via an A-D conversion circuit 31. 3
Reference numeral 3 denotes a scanning circuit for scanning the CRT display 32, in which vertical scanning is performed for each display pixel column based on the output counts of the row counter 28 and column counter 29. Note that the reference clock pulse source 27 sends out pulses with a waveform rate of 1/2, and during either the high or low sending period, the address switchers 14 and 26 guide the write address to the storage circuits 15 and 21, and simultaneously store the address. Circuits 15 and 21 are also put into the write state. Conversely, when the address switchers 14 and 26 send out a read address, the memory circuits 15 and 21 are placed in the read state.

As described above, the detection information within the entire detection range angle is displayed in rows 1 to 2n of the display pixel column of the CRT display 32, and the detection information over time in a specific direction φ' is displayed in rows 2n+1 to 2n+i. Information will be displayed.

On the other hand, FIG. 4 shows another embodiment, in which detection information in the wave transmission/reception direction α (accurately within the range α±β) is displayed over time. Reference numeral 17' denotes an azimuth setting device for specifying any one of the wave transmitting/receiving directions α of the transducer 3 set in advance within the entire detection range angle, and the set value α' and the detection angle α by the detection circuit 10 are If they match, a matching pulse is sent out from the comparator circuit 19 during that time (until the time of transmitting/receiving waves in that direction or the time of completion of receiving waves). Due to the coincidence pulse, the detection signal from the time series circuit 4 passes through the gate 20 as described above, and the write address of the memory circuit 25 is designated.
The signal passing through the gate 20 is integrated by an integrating circuit 34. That is, the detection signal every 1 (m) in the directions α'-β to α'+β is integrated, and the final value thereof is written into the memory circuit 21 and at the same time is reset by the reset output pulse from the direction counter 5. .

As explained above, according to the present invention, although it is only a part of the detection signal, it is possible to display the plane (longitudinal) component and the time direction three-dimensionally, and the detection time within the entire detection range angle is also significantly shortened. Therefore, there is little leakage in the time-lapse signal and it is relatively continuous.

In this embodiment, two memory circuits are used, one for longitudinal section and one for time course, but for example, a specified detection signal for time course display may be once stored in a shift register etc. every time the entire detection range angle is detected. If this is written in each column during the so-called idle time when the transducer 3 rotates, it can be realized with one memory circuit.

Further, the parallel writing signal is not limited to the horizontal writing type, but may be the vertical writing type. In such a case, it is necessary to make the row addresses of each memory circuit continuous and divide the memory circuit into two at a certain address.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing one embodiment of the present invention. FIG. 2 is a detailed circuit diagram of the transducer 3.
FIG. 3 is a diagram for explaining coordinate transformation.
FIG. 4 is a partial circuit diagram showing another embodiment of the present invention.

Claims (1)

[Claims] 1. An ultrasonic pulse that is equipped on a moving ship and transmits ultrasonic pulses in a preset angle direction that is relatively narrow compared to the wide angle range used for underwater detection, and reflected waves that return from each direction. The ultrasonic transducer receives waves separately in each direction with multiple reception beams each having directivity in each direction.The ultrasonic transducer is rotated to flatten the water in a wide range of angular directions in an almost vertical direction under the ship. The reflected signal that arrived from this wide angle direction and was captured by the received beam is displayed on a part of the display screen of the display unit, and the reflected signal that arrived from any one of the above wide angle directions is displayed on the other part of the display screen. In an underwater detection display device that displays signals over time, the plurality of directional receivers are arranged so that the reflected waves on approximately equidistant lines within the set range angle are time-series in synchronization with the transmission of the ultrasonic pulse. a time-series circuit that time-series the received signal captured by the wave beam; a rotation device that rotates the ultrasonic transducer by a certain angle within the range angle; a directional azimuth of the ultrasonic transducer determined by the rotation device; and a time series signal sent from the time series circuit. a coordinate converter that converts the azimuth and distance position of the time series signal to corresponding pixel positions on the display screen based on the azimuth and distance data of the display; and each pixel of a part of the display screen of the display device. a first storage section having a storage address corresponding to the position; and a first storage section that writes the time-series signal sent from the time-series circuit to the storage address of the first storage section specified by the coordinate converter. a writing circuit, a scanning circuit that repeatedly performs pixel scanning on the display, and a storage address of the first storage section corresponding to a pixel position on the display screen in synchronization with the pixel scanning of the scanning circuit. a first readout circuit that specifies and reads out the stored signal and supplies it to the display; an extraction circuit that extracts only a signal from any one direction within the range angle in which the underwater detection is performed; a second memory section having memory addresses corresponding to respective pixel positions of other parts of the display screen; and a second memory section that sequentially writes the signals sent from the extraction circuit to predetermined memory addresses of the second memory section. An underwater detection display device comprising: a second readout circuit that reads out the stored signal and supplies it to the display device in synchronization with the pixel scanning of the scanning circuit. 2 Equipped on a moving ship, it transmits ultrasonic pulses in a preset angle direction that is relatively narrow compared to the wide range of angles used for underwater detection, and directs the reflected waves returning from each direction in each direction. The ultrasonic transducer, which receives waves separately in each direction using multiple receiving beams with different characteristics, is rotated to search underwater in a wide angular direction in a nearly vertical direction under the ship. A part of the display screen displays the reflected signals that arrived from this wide angle direction and was captured by the receiving beam, and the other part of the display screen displays the reflected signals that arrived from any consecutive multiple directions in the wide angle direction over time. In an underwater detection display device that displays the above-mentioned ultrasonic pulses, the reflected waves on approximately equidistant lines within the set range angle are chronologically arranged into the plurality of directional reception beams in synchronization with the transmission of the ultrasonic pulses. a time-series circuit that time-series the received signal captured by the ultrasonic transducer; a rotation device that rotates by a certain angle within the range angle; a directional azimuth of the ultrasonic transducer determined by the rotation device and an azimuth of the time series signal sent from the time series circuit; a coordinate converter that converts the azimuth and distance position of the time series signal to corresponding pixel positions on the display screen based on distance data; and a coordinate converter that corresponds to each pixel position of a part of the display screen of the display device. a first storage section having a storage address for the first storage section; and a first write operation for writing the time series signal sent from the time series circuit into the storage address of the first storage section designated by the coordinate converter. a scanning circuit that repeatedly performs pixel scanning on the display device; and a scanning circuit that specifies a memory address in the first storage unit that corresponds to a pixel position on the display screen in synchronization with the pixel scanning of the scanning circuit. a first readout circuit that reads out the stored signal and supplies it to the display; and a first readout circuit that reads out the stored signal and supplies it to the display, and extracts only signals from arbitrary consecutive directions within the range angle in which the underwater detection is performed, and based on these extracted signals. a signal generation circuit that generates a display signal; a second storage section having memory addresses corresponding to respective pixel positions on the other part of the display screen of the display device; A second write circuit that sequentially writes data to predetermined memory addresses in a second memory section; and a second read circuit that reads out the stored signal and supplies it to the display device in synchronization with pixel scanning of the scan circuit. Underwater detection display device.