JPH0479549B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an underwater detection device that detects underwater in a wide range of directions by transmitting and receiving ultrasonic pulses in a wide range of directions. Concerning reducing impacts.

(Prior Art) When instantly detecting underwater in a wide range of directions, generally, ultrasonic pulses are simultaneously transmitted in a wide range of directions, and reflected waves returning from each direction are extracted separately for each direction. The reflected waves in each direction can be extracted by receiving the reflected waves returning from each direction with multiple ultrasonic transducers and phase-synthesizing the received signals of each transducer in a known manner. A directional reception beam having reception sensitivity in the direction is formed. A large number of directional receiving beams are formed in each direction, and reflected waves returning from each direction are received separately in each direction by the directional receiving beams in each direction.

In the above, when phase-synthesizing the reception signals of the ultrasonic transducers of the plurality of bins, the strongest reception sensitivity is formed in a specific direction, and at the same time, extremely weak reception sensitivity is also formed in unnecessary directions. This receiving sensitivity in unnecessary directions is usually called a sub-pole beam.

In the above-mentioned wide range underwater detection device, if the intensity of the reflected wave returning from the direction of the sub-pole beam is relatively strong, various problems will occur in the displayed image. For example, when transmitting ultrasonic pulses in a wide range of angular directions including the seabed directly below and receiving the reflected waves, extremely strong reflected waves return from the direction of the seabed directly below. Therefore, even when the receiving beam formed by the above phase combination is directed in an oblique direction rather than directly below, the reflected wave from the seabed directly below is received by the sub-pole beam. Ru. As a result, the received signal from the sub-pole beam is displayed as a virtual image on the displayed image. In FIG. 2, B shows a true seabed line display image, and B shows a virtual image of the seafloor created by the sub-pole beam.

(Problems to be Solved by the Invention) As an underwater detection device for reducing such virtual images, the applicant proposed the one described in Japanese Patent Application Laid-Open No. 58-214867. This is done by dividing the wide range angle θ into 2 or more, changing the transmission time of the ultrasonic pulse for each division, and making the difference in transmission time into a directional receiving beam that lags behind the seafloor reflected waves received by the main beam. It is set so that the sub-beam reflected waves from the seabed are received. However, due to this difference in transmission time,
The scanning cycle for a wide range of angles θ will be limited. Therefore, in addition to reducing the virtual image, this invention
The present invention aims to provide an underwater detection device in which the scanning cycle is not limited.

(Means and operations for solving the problem) As a means for solving the problem, an ultrasonic transducer 1 in which n ultrasonic transducers are arranged and transmits and receives ultrasonic pulses in a wide range angle θ direction is provided. And, the above wide range angle θ is divided into two or more m intervals θ ₁ , θ ₂ , θ ₃ ,
Divide into θ ₄ and transmit detection signals of the first to m-th frequencies f ₀₁ , f ₀₂ , f ₀₃ , f ₀₄ with mutually different carrier frequencies using the ultrasonic receiver/transmitter 1 in the corresponding sections. A transmission signal generation device 2 as a detection signal generation means, and an echo signal of the detection signal returning from the wide angle θ direction are transmitted from the first frequency to the m-th frequency by the ultrasonic transducer 1, the mixed signal generator 9, etc. By receiving the echo signals separately for each frequency, and phase-shifting and phase-synthesizing the echo signals for each frequency using the movement controller 8, multiplexer 10, etc., the a receiving means 17 that forms a directional reception beam for each of the first to m-th frequencies and captures the echo signals of the first to m-th frequencies returning from each section; and the first to m-th sections θ ₁ , θ ₂ , θ ₃ , θ ₄ , and is captured by the directional reception beams formed sequentially at θ 2 , θ 3 , θ 4 and sequentially supplied by the multiplexer 10 or the like, display means 18 is provided for displaying echo signals arriving from a wide range of angles θ.

That is, dividing the wide angle θ direction into m sections,
Ultrasonic pulses with different frequencies are transmitted in each section, and different frequencies (1st frequency to m-th frequency) are transmitted.
Since a directional receiving beam is formed and scanned every time,
The reflected waves returning from each section are captured by the sub-poles of the directional reception beams formed in other sections, thereby eliminating the possibility of producing false images on the display.

(Example) In FIG. 1, 1 is an ultrasonic transducer, 2 is a transmission signal generator as a detection signal generating means, 17 is a receiving means, and 18 is a display means.

The ultrasonic transducer 1 is 8 in this embodiment.
Consisting of ultrasonic transducers 101 to 108,
Based on the transmission signal generator 2, ultrasonic pulses are transmitted in a wide range of angles θ direction. Furthermore, when transmitting ultrasonic pulses in the wide angle θ direction, the ultrasonic transducer 1 divides the wide angle θ into m intervals for each specific angle, and transmits ultrasonic pulses of different frequencies in each direction. do. For example, as shown in Figure 3, the total range angle θ for transmitting ultrasonic pulses is divided into four angles, θ ₁ , θ ₂ , θ ₃ , and θ ₄ , and the distance between the angles of θ ₁ is f. An ultrasonic pulse of ₀₁ is transmitted, and ultrasonic pulses of f ₀₂ , f ₀₃ , and f ₀₄ are transmitted between the respective angles of θ ₂ , θ ₃ , and θ ₄ .
Note that the transmission signal guided from the transmission signal generator to the ultrasonic transducer 1 is transmitted through transmission/reception switching circuits 301 to 308.
are guided to ultrasonic transducers 101 to 108, respectively.

The ultrasonic transducer 1 transmits ultrasonic pulses into the water, receives the reflected waves from the water, and transmits the received signals of the ultrasonic transducers 101 to 108 via the transceiver switchers 301 to 308. Phase shifters 4, 5, 6 and 7
Commonly sent to each. Each phase shifter 4, 5,
6 and 7 are constructed in the same way, and regarding the phase shifter 4, mixing circuits 401 to 408, a filter 4
11 to 418 and mixing circuits 421 to 428. The mixing circuits 401 to 408 and the filters 411 to 418 are connected to the ultrasonic transducer 1.
A specific frequency signal is selected from among the received signals of 01 to 108. Mixing circuits 421 to 428 phase shift the selected frequency signals by specific amounts. This phase shift amount is determined by the phase shift frequency signal output from the phase shift controller 8. Further, selection of a specific frequency signal is performed based on a mixed signal output from the selection mixed signal generator 9.

The phase shift controller 8 generates multiphase frequency signals having a common frequency and different phases. Since eight mixing circuits 421 to 428 are used in the embodiment, eight phase frequency signals are generated, and each phase frequency signal is guided to each of the mixing circuits 421 to 428. Each phase frequency signal is similarly guided to the other phase shifters 5, 6, and 7. On the other hand, the mixed signal generator 9
generates a plurality of frequency signals corresponding to each of the phase shifters 4, 5, 6, and 7. That is, a frequency signal of f ₁₁ is generated for the phase shifter 4, and the mixing circuit 40
1 to 408. Also, phase shifters 5, 6, 7
For each of the frequency signals f ₁₂ , f ₁₃ , and f ₁₄ are generated and guided to the mixing circuit of each phase shifter.

Each frequency signal subjected to phase shift control in the phase shifters 4, 5, 6, and 7 is guided to a multiplexer 10, and the frequency signal of one of the phase shifters is selected. The multiplexer 10 is a counter 80 of the phase shift controller 8.
A switching operation is performed based on the count value of 1, and each output wave of the phase shifters 4, 5, 6, and 7 is sequentially switched and output.

The output frequency signal of multiplexer 10 is sent to adder 1
I am guided by 1. Therefore, the adder 11, for example,
When the frequency signals of the phase shifter 4 are guided, the frequency signals are added together and output.

The frequency signals added by the adder 11 are guided to the filter 12 and a specific frequency signal is extracted.
The signal is guided to the amplifier 16. The amplifier 16 amplifies the extracted signal of the filter 12 and then supplies it to the display 14 . The display 14 is, for example, a cathode ray tube display, and displays the output signal of the amplifier 16 by performing pixel scanning based on the sweep circuit 15.

Next, the transmission signal generator 2, phase shifters 4, 5, 6,
7. The operation of each part such as the phase shift controller 8 will be explained.

The transmitting signal generator 2 was filed by the applicant in a patent application filed in 1983.
A multiphase frequency signal generation device similar to that provided in Japanese Patent Publication No. 121439 (Japanese Patent Publication No. 63-063033) and described in detail below is used. That is, counter 20
When the data stored in the read-only memory 203 is read by the latch circuits 204 ₁ to 20
The 8-phase frequency signal output from 4 ₈ is guided to the ultrasonic transducers 101 to 108, and the ultrasonic transceiver 1
Ultrasonic signals are transmitted from the Note that for the 8-phase frequency signal, the data stored in the read-only memory 203 is 2.
Since it is read out as a binary value, an eight-phase rectangular wave is actually output.

The composite directivity characteristics of the ultrasonic signals transmitted from the ultrasonic transducer 1 are determined by the phase relationship of the excitation signals that excite each vibrator. The phase relationship of the excitation signal, that is, the rectangular wave train, can be arbitrarily set by appropriately setting the stored data in the read-only memory. Therefore, by appropriately writing the data stored in the read-only memory 203,
The combined directivity direction of the ultrasonic waves transmitted from the ultrasonic transducer 1 can be set to any direction.

Data stored in the read-only memory 203 is read out by the counter 201, and the readout area is switched by the numerical value setter 207. In the embodiment shown in FIG. 1, the readout area can be switched into four areas.

The numerical value setter 207 sequentially switches and designates the first area, second area, third area, and fourth area of the storage address of the read-only memory 203 in accordance with the count value of the counter 208. While the first area is designated, the rectangular wave generated by the reading of the counter 201 is transmitted to the ultrasonic transducers 101 to 108.
, an ultrasonic signal is transmitted in the θ ₁ direction in FIG. That is, in the first region, the phase relationship of the rectangular array is set so that the composite directivity characteristic of the ultrasound signals output from the ultrasound transducers 101 to 108 is in the _θ1 direction. Next, when switching to the second region, the phase relationship of each rectangular wave train is set so that the transmission direction of the ultrasonic signal is in the range angle direction of θ ₂ shown in FIG. Similarly, when switching to the third region and the fourth region, the phase relationship of the rectangular wave train is changed so that the transmission direction of the ultrasonic signal is in the respective directions of θ ₃ and θ ₄ shown in FIG. is set for each area.

Switching of the read area from the first area to the fourth area of the read-only memory 203 is performed using the counter 208.
This is done within a very short time. Counter 208 counts the pulse train of clock pulse source 210 introduced through gate 209. gate 20
9 becomes conductive when the keying pulse is sent out from the keying pulse generation circuit, and the counter 20
8 is conductive until it sends a carry pulse.

The keying pulse generation circuit 13 generates a pulse train with a period T ₀ as shown in FIG. 4a, thereby performing an ultrasonic pulse transmission operation.

When keying pulse a is output, gate 2
09 becomes conductive, the counter 208 is reset. As shown in FIG. 4b, the counter 208 performs quaternary counting during time Ts when the gate 209 is conductive, and switches the readout area from the first area to the fourth area of the read-only memory 203. Let's do it. This switching time Ts is performed in an extremely short time. For example, an ultrasonic pulse transmitted in the θ ₁ direction in FIG. 3 based on the data stored in the first area and an ultrasound pulse transmitted in the θ ₄ direction based on the stored data in the fourth area are equidistant. When the ultrasonic pulse is reflected from a reflector on the line and returns home, the distance deviation corresponding to the time deviation in transmitting the ultrasonic pulse is set to an almost negligible degree in consideration of the distance resolution of the ultrasonic pulse.

The gate 209 is made conductive by the keying pulse a for a time Ts until the carry pulse (FIG. 4c) of the counter 208 is output, and the pulse train of the clock pulse source 210 is passed to the counter 208.
Send to 8. At the same time, this pulse train is also guided to the gate pulse generation circuit 214. Then, the gate pulse generation circuit 214 generates gate pulses P ₁ , P ₂ , P ₃ ,
Generate _P4 . These gate pulses P ₁ , P ₂ , P ₃ ,
P ₄ allows the rectangular wave trains output from the gates 215 ₁ to 215 ₈ to pass only when gate pulses P ₁ , P ₂ , P ₃ , and P ₄ appear. The rectangular wave train passing through the gates 215 ₁ to 215 ₈ is converted into power amplifiers 216 ₁ to 216 ₈
After being amplified at , the signals are transmitted as ultrasonic pulses from the ultrasonic transducers 101 to 108 via switchers 301 to 308.

The counter 208 controls the numerical value setter 207 as described above to control the transmission direction of the ultrasonic pulse, and at the same time controls the frequency of the ultrasonic wave transmitted in each direction. This frequency control is performed by introducing the count value of the counter 208 to the decoder, and the decoder 212 controlling the gates 211 ₁ to 211 ₄ .

When the counter 208 changes from the reset value, the decoder 212 sequentially turns on the gates 211 ₁ to 211 ₄ according to the change in the count value. gate 2
11 to ₂₁₁₄ , the frequency-divided waves of the frequency divider circuit 202 are introduced. The frequency dividing circuit 202 divides the pulse train of the clock pulse source 206 to generate four types of divided waves having different frequencies. Therefore, when the gates 211 ₁ to 211 ₄ are made conductive in order, divided waves with different frequencies are guided to the counter 201 via the OR circuit 213, and the data stored in the read-only memory 203 is read out at different speeds, resulting in the latch circuit. It changes every time the count value of the frequency counter 208 of the rectangular wave train output from 204 ₁ to 204 ₈ changes.
Therefore, when the gate pulses P ₁ , P ₂ , P ₃ , P ₄ are output from the gate pulse generation circuit 214, rectangular wave trains with different frequencies are transmitted to the ultrasonic transducers 101 to 1.
08, ultrasonic pulses having different frequencies f ₀₁ , f ₀₂ , f ₀₃ , and f ₀₄ are transmitted in each direction of θ ₁ , θ ₂ , θ ₃ , and θ ₄ in FIG. In this case, since the ultrasonic transducers 101 to 108 are commonly used for each frequency, the ultrasonic pulse frequencies f ₀₁ , f ₀₂ ,
It is desirable that f ₀₃ and f ₀₄ be set within the resonance frequency of the ultrasonic transducer.

Next, phase shifters 4, 5, 6, 7 and phase shift controller 8
I will explain about it.

The phase shifters 4, 5, 6, and 7 are configured in the same way, and the received signals of the ultrasonic transducers 101 to 108 guided through the switching devices 301 to 308 are transmitted to the phase shifters 4, 5, 6, and 7.
6 and 7 in common.

Regarding the phase shifter 4, the ultrasonic transducer 101
The received signals from 108 to 108 are sent to mixing circuits 401 to 40.
Guided by 8. Each of the mixing circuits 401 to 408 mixes the received signals of the ultrasonic transducers 101 to 108 and the mixed signal output from the mixed signal generator 9.

The mixed signal generation circuit 9 has frequencies f ₁₁ , f ₁₂ , f ₁₃ ,
Generate four types of mixed signals of f ₁₄ . Then, a mixed signal of frequency f ₁₁ is guided to mixing circuits 401 to 408. Further, a mixed signal of frequency f ₁₂ is guided to the mixing circuits 501 to 508 of the phase shifter 5.
Further, a mixed signal of frequency f ₁₃ is introduced to mixing circuits 601 to 608 of phase shifter 6, and a mixed signal of frequency f ₁₄ is introduced to mixing circuits 701 to 708 of phase shifter 7, respectively.

Mixed signals from mixing circuits 401 to 408 are guided to filters 411 to 418 to extract specific frequency signals. The extracted signals from the filters 411 to 418 are guided to mixing circuits 421 to 428, where they are mixed with the frequency signal output from the phase shift controller 8.

The phase shift controller 8 is similar to that provided by the applicant in Japanese Patent Application No. 57-121439 (Japanese Patent Publication No. 1-016392), and as detailed below, the phase shift controller 8 is a plurality of phase shift controllers whose phase relationships are regulated in advance. Different frequency signals, in the embodiment shown in FIG. 1, eight-phase frequency signals are generated and mixed in mixing circuits 421 to 428, respectively. Then, using the phase shift component included in the mixed signal, a phase shift signal for the input signals derived from the filters 401 to 408 is generated.

In the phase shift controller 8, data stored in a read-only memory 802 is read by a counter 801, and the read data is stored in latch circuits ₈₀₃₁ to 81.
3 ₈ , the latch circuit 80
Eight-phase frequency signals are output from ₃₁ to ₈₀₃₈ . This frequency signal is actually output as an eight-phase rectangular wave train because the data stored in the read-only memory 802 is output as a binary value. In addition,
The counter 801 counts the pulse trains inputted to the frequency divider circuit 804 and the latch circuits 803 ₁ to 8.
₀₃₈ performs a latch operation using a latch pulse output from the latch pulse generation circuit 805.
Further, the latch pulse generation circuit 805 generates a latch pulse using the pulse train of the clock pulse source 806 and the output of the frequency divider circuit 804.

Each of the rectangular wave trains output from the latch circuits 803 ₁ to 803 ₈ has a specific phase relationship, but each phase, more precisely, the frequency of each rectangular wave train changes. Therefore, the phase relationship of the mixed outputs of the mixing circuits 421 to 428 also changes in accordance with the phase relationship of the rectangular wave train.

The mixed outputs of the mixing circuits 421 to 428 are added together in the adding circuit 11 via the multiplexer 10, and a specific frequency signal is selected from the added signals in the filter 17. Therefore, filter 1
On the output side of No. 2, a frequency signal obtained by phase-combining specific frequency signals among the mixed signals of the mixing circuits 421 to 428 is obtained. Therefore, the latch circuits 803 ₁ to 8
The phase relationship of the rectangular wave train output from ₀₃₈ is set so as to extract a specific frequency signal from the added signal of the mixed output as disclosed in Japanese Patent Application No. 121439/1980 (Japanese Patent Application No. 1-016392). By doing so, the receiving directivity characteristic of the transducer 1 has receiving sensitivity in a specific direction, and the receiving direction is set to the detection range angle θ shown in FIG.
can be scanned within. In this case, the received wave directivity direction is determined by the phase relationship of the rectangular wave trains output from the latch circuits 803 ₁ to 803 ₈ .
Since the phase relationship of the rectangular wave train corresponds to the count value of the counter 801, the received wave directivity direction can be known from the count value of the counter 801.

The count value output of the counter 801 is guided to the multiplexer 10, and the multiplexer 10 sends the phase shifters 4, 5, 6,
The output frequency signal of 7 is switched and guided to an adder 11.
That is, in FIG. 3, when the receiving wave direction scans the detection range angle θ from the _S1 direction to the _S2 direction,
While scanning the detection range θ ₁ , the output signal of the phase shifter 4 is guided to the adder 11 . Then, the output frequency signal of the phase shifter 5 whose reception direction scans the next detection range θ ₂ is switched and guided to the adder 11 . Similarly, when the reception direction changes to the detection ranges θ ₃ and θ ₄ , the multiplexer 10 sequentially switches the output frequency signals of the phase shifters 6 and 7 and guides them to the adder 11 .

In FIG. 3, ultrasonic signals having different frequencies are transmitted and received in each direction of the detection ranges θ ₁ , θ ₂ , θ ₃ , and θ ₄ . Therefore, the frequency signals corresponding to the detection range angles θ ₁ , θ ₂ , θ ₃ , θ ₄ of each of the phase shifters 4, 5, 6, and 7 are detected, and the phase of each frequency signal is shifted separately. . The phase shift operation at this time is based on the rectangular wave train output from the phase shift controller 8.
will be carried out in conjunction.

Each of the phase shifters 4, 5, 6, and 7 receives the received signals of the ultrasonic transducers 101 to 108 and the mixed signal generator 9.
A specific frequency signal is selected from the mixed signal. At this time, the filter 411 of each phase shifter 4, 5, 6, 7
〜418,511〜518,611〜61
8, 711 to 718 extract a common frequency signal f ₀ from each mixed signal. Also, phase shifters 4, 5,
mixed frequency signals f ₁₁ , f ₁₂ ,
f ₁₃ and f ₁₄ are received signals f ₀₁ , f ₀₂ , f ₀₃ , f 04 in detection ranges θ ₁ , θ ₂ , θ ₃ , θ ₄ of phase shifters 4, 5, 6, and _7, respectively.
Each frequency is set so that the following is extracted. For example, in the phase shifter 4, the detection range θ ₁
The mixed frequency signal f ₁₁ is set so that the received signal f ₀₁ in the direction and the mixed signal f ₁₁ are mixed, and the difference frequency component of the mixed frequency signal f ₀₁ ±f ₁₁ becomes f ₀₁ − f ₁₁ = f ₀ . has been done.

Similarly, in the phase shifter 5, the detection range θ ₂
The mixed frequency signal f ₁₂ is set so that the difference frequency component of the mixed frequency signal of the received signal f ₀₂ from the 1st and 10th generation of the mixed frequency signal f ₁₂ becomes f ₀₂ −f ₁₂ =f ₀ .

Furthermore, in the phase shifters 6 and 7, the received signals f ₀₃ and f ₀₄ from the detection ranges θ ₃ and θ ₄ and the mixed signals f ₁₃ and
The mixed frequency signals f ₁₃ and f 14 are set so that the difference frequency component between the mixed frequency signal and f ₁₄ becomes f _{03 −f 13} =f ₀ f ₀₄ −f ₁₄ =f ₀ .

Therefore, each of the phase shifters 4, 5, 6, 7
The reflected waves returning from the detection range angles θ ₁ , θ ₂ , θ ₃ , and θ ₄ in the figure are detected separately, and each detection signal is converted into a similar signal using a rectangular wave train derived from the phase shift controller 8. After performing phase shift control, the signal is output to the multiplexer 10. Then, the multiplexer 10 switches and outputs the output frequency signal of each phase shifter as described above.

As a result of the above, the filter 12 outputs a directional reception signal whose reception direction changes within the detection range angle θ shown in FIG. This directional received signal is guided to the display 14 via an amplifier 16. The received signals in each direction sent out in time series from the filter 12 are each amplified by the amplifier 16 and then guided to the luminance terminal of the display 19. In the display device 14, a fan-shaped lath is formed by guiding a sweep wave from the sweep circuit 15 to the deflection coil.
The sweep operation of the sweep circuit 15 is performed in conjunction with the counting operation of the keying pulse generation circuit 13. That is, the keying pulse generation circuit 13 periodically transmits ultrasonic pulses from the ultrasonic transducer 1 in a wide range direction via the transmission signal generation circuit 2, and simultaneously transmits ultrasonic pulses from the ultrasonic transducer 1 to the counter 801 of the phase shift controller 8 and the sweep circuit. 15 is reset to match the direction of the received signal and the direction of sweep of the display 14.

In addition, in FIG. 1, the transducer 1 is drawn as if the ultrasonic transducers 101 to 108 are arranged in a straight line, but the ultrasonic transducers 101 to 1
08 may be arranged in a circular or curved shape.
The composite directional characteristics of the ultrasound waves transmitted from the ultrasound transducers 101 to 108 are determined by the phase relationship of the excitation signals of each transducer, and the phase relationship of the excitation signals is determined by the writing of data stored in the read-only memory 203. Therefore, it can be set arbitrarily. Therefore, the arrangement shape of the ultrasonic transducers 101 to 108 does not need to be limited to a specific shape. Further, although the transmission signal generator 2 and the phase shift controller 8 have been described as outputting a rectangular wave train, the generated rectangular wave train may be converted into a sine wave and output.

(Effects of the Invention) As described above, according to the present invention, the underwater detection range angle θ by ultrasonic pulses is divided into a plurality of sections, and ultrasonic pulses of different frequencies are transmitted for each section. Then, a directional receiving beam is formed for each frequency signal. Therefore, since the detection range of each section is separated by _frequency , for example, in _FIG . No received signal is generated in the wave beam. That is, even if a sub-pole occurs in the directional reception beam at the detection range angle θ ₁ , the reflected wave from the direction of the detection range angle θ ₂ will not be received by the sub-pole. Therefore, the reflected waves returning from the water can be accurately displayed without creating a virtual image on the display screen due to the subpole of the receiving beam, unlike the conventional wide-range underwater detection device. Further, the ultrasonic pulses having different frequencies for each section have fewer restrictions on the scanning cycle than the ultrasonic pulses having different transmission times for each section.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the present invention, FIG. 2 shows an example of a display by a conventional underwater detection device, FIG. 3 is a diagram for explaining the transmission operation in the embodiment of this invention, and FIG. The figure shows a waveform diagram for explaining the operation. 1... Ultrasonic transducer, 101 to 108...
Ultrasonic transducer, 2... Transmission signal generator, 201...
... Counter, 202 ... Frequency divider circuit, 203 ...
Read-only memory, 204 ₁ to 204 ₈ ... Latch circuit, 205 ... Latch pulse generation circuit, 20
6...Clock pulse source, 207...Numeric value setter, 208...Counter, 209...Gate,
210...Clock pulse source, 211 ₁ to 21
1 ₄ ...Gate, 212...Decoder, 213...
...OR circuit, 214...gate pulse generation circuit,
215 ₁ to 215 ₈ ... gate, 216 ₁ to 2
16 ₈ ... Power amplifier, 301 to 308... Transmission/reception switch, 4, 5, 6, 7... Phase shifter, 401 to 408, 501 to 508, 601 to 60
8,701 to 708...Mixing circuit, 411 to 418, 511 to 518, 611 to 618,
711 to 718...Filter, 421 to 4
28,521 to 528,621 to 628,7
21 to 728...mixing circuit, 8...phase shift controller, 801...counter, 803...read-only memory, ₈₀₃₁ to ₈₀₃₈ ...latch circuit,
804... Frequency divider circuit, 805... Latch pulse generation circuit, 806... Clock pulse source, 9... Mixed signal generation circuit, 10... Multiplexer, 11
... Addition circuit, 12 ... Filter, 13 ... Keying pulse generation circuit, 14 ... Display device, 15
... sweep circuit, 16 ... amplifier, 17 ... receiving means, 18 ... display means.

Claims (1)

[Claims] 1. An ultrasonic transducer in which n ultrasonic transducers are arranged and transmit and receive ultrasonic pulses in the direction of a wide angle θ, and the wide angle θ is divided into two or more m sections, detection signal generating means for transmitting detection signals of first to m-th frequencies having mutually different carrier frequencies using the ultrasonic transducer in each corresponding section; and each section of the first to m-th sections. a receiving means for forming a directional receiving beam for each of the corresponding first to m-th frequencies and capturing echo signals of the first to m-th frequencies returning to each section; An underwater detection device characterized by comprising display means for displaying echo signals arriving from a wide range angle θ captured and sequentially supplied by the directional reception beams sequentially formed in the m-th section.