JP2577333B2 - Scanning sonar receiver - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to sharpening of a receiving beam of a scanning sonar,
The present invention relates to a technique for downsizing a transducer.

(Prior Art) In a scanning sonar, the transmission beam width is set to be much larger than the reception beam width, so that the azimuth resolution is determined by the reception beam width. When the ratio of the wavelength to the diameter of the transmitter / receiver is constant, the reception beam width is set to the width of the reception vibration surface (hereinafter abbreviated as reception surface width) which is equivalent to the planar projection width of the group of transducers for forming the reception beam. Since the value is inversely proportional, it is necessary to set a wide receiving surface width in order to sharpen the receiving beam.

Here, in general, the interval between the oscillators is suppressed to about half of the wavelength from the viewpoint of sublobe suppression, and the amplitude of the reception output of the pair of adjacent oscillators is interlocked after being attenuated and interpolated to interpolate between the outputs of the pair. It is carried out.

This will be described below with reference to the drawings. FIG. 8 is an example of the whole scanning sonar, and FIGS. 9 and 10 are explanatory views of the formation of the reception beam and the reception beam for interpolation.

In FIG. 8, reference numeral 1 denotes a transducer arranged in a circular array of transducers.
The receiving beam width of each of the transducers is set to be sufficiently large as compared with the combined receiving beam width. 2 is an electronic switch for selectively connecting oscillators 11 to 14 for receiving beam formation and interpolation, and then for time T _0.
The transducer is sequentially switched in the θ direction every time. 3 is composed of the same interpolator 31, 32 and 33 in the interpolation unit, the output of the pair of transducers that respectively adjacent (eg E _1, E ₂₎ receiving one of the outputs during the time T ₀ (E ₁₎ From the other (E ₂ ) the amplitude is almost constant,
Output (E _o ) whose phase is shifted so that the receive beam rotates
Is formed and output. Reference numeral 4 denotes a phase shift unit. The phase shift circuit 41 constituting the phase shift unit shifts and compensates the phase difference due to the geometrical arrangement between the vibrators, and outputs the same in phase. Reference numeral 5 denotes a combining circuit, which combines the outputs from the phase shift unit 4 and outputs a reception beam output OP that rotates in the θ direction every moment.

FIG. 9 shows the interpolation circuit 31 shown in FIG. 8 which has the same configuration as the other interpolation circuits 32 and 33 and operates in the same manner.

The interpolation circuit 31 is a combination circuit that combines both the attenuation circuits 311 and 312 whose attenuation ratios are changed by electronic control and their outputs.
It is composed of 313.

The attenuation circuit 311 and 312 control the output E _s1 from the pulse generating circuit short in the figure, each damping ratio during the time T ₀ alpha, beta is, alpha is O 100%, from beta 0 100% The relationship between α and β has been devised in various ways, but here it is assumed that α and β are in a complement relationship assuming that the attenuation circuit has the simplest configuration. Next, a pair of outputs E ₁ and E ₂ from the adjacent oscillators 11 and 12 are used as damping circuits.
Attenuated by 311 and 312 to become αE ₁ and βE ₂ respectively,
Next, they are combined by the combining circuit 313 and output as an interpolation output _Eo .

FIG. 10 (a) shows the relationship between the outputs of the interpolation circuit 31. The phase angle φ _s represents the phase difference between the pair of reception outputs E ₁ and E ₂ , and the phase angle φ _o represents the interpolation output E _o. There shows the angle that is phase-shifted towards more reception output E ₁ to reception output E _2. In the range the phase difference phi _s between reception output E _1, E ₂ is not so large as in FIG. (A), the amplitude of the interpolated output E _o is substantially equal to the reception output E _1, E ₂ amplitude, the angle phi _o is the phase shift can be practical for causing regarded as substantially equal to βφ _s.

Next, in order to set the gap between the transducers to be close to a half wavelength and to sharpen the reception beam width, the transducer at a position far away from the main axis direction of the reception beam, for example, the vibration shown in FIG. A case in which the child 16 and 17 are used will be described.

In FIG. 10 (c), the signal output by the signal S entering the oscillators 16 and 17 from the main axis direction is E ₆ and E ₇ , respectively, and the interference sound of the other ship from the direction entering both oscillators in the same phase. (The frequency is the same as the signal S but the phase is different.) The noise outputs of the vibrators 16 and 17 due to N are E _N6 and E _N7 , respectively, and the signal outputs E ₆ and E ₇ as shown in FIG. The phase difference between φ _s , the phase difference between the noise outputs E _N6 , E _N7 and the signal output E ₆ is φ _N, and the attenuation ratios α and β of the attenuation circuit of the interpolation circuit 31 (FIG. 9), respectively. When the value is set to 0.5, the amplitude of the combined output _Eo of the combined signal after being attenuated is reduced compared to the amplitude of the reception outputs E ₆ and E ₇ , but the combination of the noise outputs E _N6 and E _N7 Output E
Amplitude of _No does not change the E _N6.

(Problems to be solved by the invention) However, as shown in FIG. 10 (b), the reception outputs E ₁ and E ₂
In the case where the phase difference φ _s between them is 180 ° or φ ′ _s (received wave output E ′ ₁ ) exceeding 180 °, the above interpolation means uses 180 °.
The amplitude of the interpolated output E _o in the case of 0, also is the case in excess of 180 ° resulting amplitude of the output E _o, the phase advance angle has a disadvantage to be interpolated impossible becomes negative.

The amplitude of FIG. 10 (d) composite output E _o As can be seen from the reduced compared to the amplitude of the received wave output, noise output
The amplitude of the combined output E _No of E _N6 and E _N7 is not different from that of E _N6, and as a result, the signal-to-noise ratio is reduced. The interpolation circuit 31
When the attenuation ratios α and β of the electronically controlled and variably linked attenuation circuits 311 and 312 are sufficient in a complement relation, a D / A converter of a high-quality and low-priced semiconductor integrated circuit can be directly used as the attenuation circuit. However, the conventional D / A converter has a drawback that if the phase difference between the paired outputs exceeds several tens of degrees, a decrease in the interpolation output and a shift in the advance angle cannot be ignored.

As described above, in the related art, it is difficult to obtain an interpolation output when the phase difference between the pair of reception outputs is close to 180 °, and the side noise also increases. Since only the transducer at the position can be used, there is a disadvantage that the sharpening of the receiving beam width is limited in the case of a transducer having a fixed wavelength and a fixed diameter.

As a countermeasure, if the wave receiving surface width is increased by reducing the interval between the oscillators, the number of preamplifiers and interpolation circuits combined with the oscillator increases, which increases the cost and space, but decreases the reliability and reduces the frequency. However, there are problems such as difficulty in acoustic and electrical insulation between transducers, and reduction in signal-to-noise ratio.

The present invention aims at solving such a drawback, and does not directly perform interpolation between a pair of reception outputs from adjacent transducers, but is disposed at an appropriate phase interval between phase differences between the pair outputs, An appropriate number of fixed interpolation outputs whose amplitudes are equal to the reception output are created, a pair of outputs having a small phase difference is sequentially taken out as a time-series output from each of these outputs, and interpolation between successive pairs of outputs is performed. Comprehensively, it is possible to extract an interpolated output having a small change in amplitude and a small shift in phase shift angle from a pair of received outputs having a large phase difference. Increase the number of transducers contributing to the noise and increase the receiving surface width to sharpen the receiving beam, and increase the spacing between the transducers to reduce the cost and improve the signal-to-noise ratio during interpolation. Can be scanning sonar reception It is to provide a location.

(Means for Solving the Problems) The present invention has the following means configuration in order to achieve the above object.

That is, the scanning sonar receiver of the present invention selects a plurality of adjacent vibrator groups from the circularly arranged vibrator group, sequentially switches the same, and aligns each phase of the selected vibrator output to the same phase. In a scanning sonar that combines and forms a receiving beam and circulates; from a pair of receiving outputs from adjacent vibrators, respective outputs are formed in phase shift, and each amplitude is equal to the amplitude of the receiving output; Means for forming and outputting an appropriate number of fixed interpolated outputs arranged for each appropriately selected phase angle between the phase differences between the pair of received outputs (phase shift circuits); From among the outputs arranged in the order in which the fixed interpolation outputs are inserted in the order of the phases between the outputs, outputs which are always adjacent in phase are paired, and are alternately arranged alternately in phase at an appropriate period. Fetched output, and Means (electronic switch) for taking out and outputting the time width of the time series output of the pair as the switching period of the vibrator; output of the output to the time series output of the pair for each period in which both time series outputs of the pair are switched at the time of formation Amplitude from 0 to 100%
Means for providing a pair of attenuations alternately increasing and decreasing in the opposite phase and then combining and outputting (interpolation circuit); and a means for determining the combined output after attenuation by the geometrical arrangement of each output. Means (phase shift circuit) for compensating and extracting the phase difference, and then combining and outputting the phase difference.

(Embodiment) Hereinafter, an embodiment of the scanning sonar receiver of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of a main part of an embodiment of the present invention. Numeral 1 designates a transducer which comprises oscillators 10 and 11 arranged in a circle at a wider interval than the conventional one, and numeral 2 designates an electronic switch which is selected to constitute a wider receiving surface for receiving beam formation and interpolation. of select transducers 11-16 are sequentially switched toward the turning direction θ a vibrator for each time T _0. Reference numeral 6 denotes a signal generation unit which is composed of signal generation circuits 61 to 65. Each signal generation circuit receives a pair of received wave outputs from adjacent vibrators and appropriately selects a phase difference between the paired outputs. An appropriate number of fixed interpolation outputs are arranged at a narrow phase angle interval and the amplitude of which is equal to the amplitude of the received output, and these created outputs are inserted between the received outputs, and the like. all outputs sequentially taken out by selecting each appropriate time and alternately in the order of phase, forms and outputs a time series output of the pair of the time width T _0. Reference numeral 7 denotes an interpolating unit composed of interpolating circuits 71 to 75. The interpolating circuits 71 to 75 increase or decrease the attenuation at appropriate time intervals to the time series outputs of the respective pairs from the signal generating circuits 61 to 65. Are combined and output. Reference numeral 8 denotes a phase shift unit, which is composed of phase shift circuits 81 and 82. The phase shift circuits 81 and 82 appropriately shift the phases of the outputs of the interpolation circuits 71 to 75 and output the signals in the same phase. Reference numeral 9 denotes a combining circuit that combines the outputs of the phase shifter 8 to form and output a reception beam output that interpolates and turns.

First, the signal generation circuit 61 will be described. The signal generating circuit 61 includes a phase shift circuit 611, an electronic switch 620, and a frequency dividing circuit 623 as shown in FIG. In the phase shift circuit 611, as shown in FIG. 3, the width is set under the condition described later in the width of the phase difference φ _s between the pair of reception outputs E ₁ and E ₂ from the adjacent vibrators. each _s is less than the phase angle, and its amplitude is fixed interpolated output an appropriate number equal to the amplitude of the received wave output E _1, E ₂ is generated from the received wave output E _1, E _2.

The phase angle ( _φι ) set here is selected as follows. As shown in FIG. 3 (b), at the outputs E _ι1 and E _ι2 having the same phase angle φ _ι and the same amplitude, the attenuation ratio α for changing the amplitude of the output E _ι1 from 100% to 0 and the amplitude of the output E _ι2 the change from 0 to 100%, a and α and damping ratio in the complement relationship beta, respectively output E _Iota1, output .alpha.E _Iota1 formed by multiplying the E _Iota2, the amplitude of the output E _Oiota formed by combining the beta E _Iota2 , equal to practical use E _Iota1 to changes in alpha, and the phase angle phi _Oiota between the output Oiota the output E _Iota1 is selected maximum angle phi _iota thereby regarded as practically equal to βφ _ι. Then as shown in FIG. 3 (a), a value obtained by dividing the phase angle phi _iota was selected phase difference phi _s between reception output E _1, E ₂ pairs the phase angle phi _iota to be a suitable integer Review and decide.

Figure 3 (a) showed a fixed interpolation output formed a case where the ratio of _ι phase difference phi _s and phase angle phi and 7 as an example as E ₁₁ to E _18.

Next, a phase shift circuit 611 is provided as shown in FIG.
A, 611B, and the reception output E ₁ by the phase shift circuit 611A.
The fixed interpolation outputs E ₁₁ , E ₁₃ , E ₁₅ and E ₁₇ are formed from the received output E ₂ and the fixed interpolation outputs E ₁₂ , E ₁₄ and E by the phase shift circuit 611B.
_16, E ₁₈ are formed respectively output. The reason why the fixed interpolation output is divided and formed in this way will be described later. Phase shift circuit 611A is configured phase of the received wave output E ₁ by an operational amplifier 632 having a resistor 631 is inverted output -E is formed as in the fourth diagram (a). Then the output E ₁₃ by reactance 633 and the resistor 634 is branched from the combined output of the output E ₁ and -E ₁ (ab in Fig. (B)). Reactance here
633 and the ratio of the respective values of the resistor 634, the amplitude of the branched outputs E ₁₃ as in the fourth diagram (b) is equal to the amplitude of the received wave output E _1,
And since the phase of the branched output E ₁₃ is are set in advance so as to be formed by the phase advance only 2 [phi _{s /} 7 from reception output E _1, branch outputs E ₁₃ is received wave output E ₁ phase 2 [phi _s / Output as an output shifted by seven. First, the voltages E633 and E634 in FIG. 9B are shown with the voltages of the reactance 633 and the resistor 634 orthogonal to each other, respectively. 635 and 636 and 637 and 638 of reactance and resistance set in the same way
Output E ₁₅ and E ₁₇ are branched respectively output as output respectively 4φ _{s /} 7 and 6φ _{s /} 7 phase a receive output E ₁ phase as in the fourth diagram (b) by. Thus phase from each reception output E ₁ by the phase shift circuit 611A by 2φ _{s /} 7,4φ _{s /} 7 and 6φ _{s /} 7 by advanced output E
_13, E ₁₅ and E ₁₇ are formed and outputted.

The phase shift circuit 611B is configured as shown in FIG. 4A similarly to 611A, and its output is formed as shown in FIG. That reception output E ₂ to FIG. (A) is an output E ₂ formed as the figure phase is inverted by the resistor 641 and the operational amplifier 642 (c), also reception output E ₂ and the inverting output - The composite output of E ₂
(output between cd) and the reactances 644, 646, 648 and the resistance 64 of the values set in the same manner as the phase shift circuit 611A described above.
Output E ₁₂ formed by 3,645,647, E _14, E ₁₆ is, 6φ _s / 7,4 each way from the received wave output E ₂ FIG (c)
It is output with a phase difference of φ _s / 7 and 2φ _s / 7. In this way, each fixed interpolation output E shown in FIG. 3A is generated by the phase shift circuit 611 composed of the phase shift circuits 611A and 611B shown in FIG.
₁₁ to E ₁₈ are formed and outputted.

The electronic switch 620 (FIG. 2) comprises electronic switches 621 and 622 that alternately advance. Electronic switch 621, 622
Is the control output E _s2 from the pulse generation circuit omitted in the figure.
The frequency dividing circuit 623 by dividing it formed the control output E _s3, switched alternately at intervals of time T _0/7 of FIG. 6 (1), a fixed interpolation output from the phase shifting circuit 611 E ₁₁ to E ₁₈ the figure (2), (3) are arranged as, a time width T _0, the signal generating circuit 61 and the time series output E _a pair of phase difference phi _{s /} 7, as E _B Output from Incidentally output E _A, each of the phase phi _A of E _B, φ _B is over time as in FIG. 6 (4) 2
The phase is shifted by φ _s / 7 each.

In FIG. 1, among the transducers 11 to 16 selected for receiving beam formation, the transducers are located near the center, and the phase difference between the reception outputs of the adjacent transducers is equal to the peripheral transducers 11, 12 and
It is small compared to the phase difference between the receiving power of each pair from 15 and 16.

Here, the signal generating circuit 63 of FIG. 1 having a simple structure suitable for a case where the phase difference between the outputs of the pair of vibrators is small will be described. The signal generating circuit 63 includes a phase shift circuit 651, an electronic switch 650, and a frequency dividing circuit 653 as shown in FIG. In the phase shift circuit 651, the pair of received outputs E ₃ and E ₄ (phase difference φ _s34 ) from the adjacent vibrators as shown in FIG. 5B are _{converted to} the phase shift circuit 651 in FIG. Resistance 661, 66
2, 663, 664 'respectively attenuated γ times, γE ₃ ,
After a .GAMMA.E _4, it is synthesized by the synthesis circuit 664, the output E
Output as ₃₄ . Here, as shown in FIG. 5B, the attenuation ratio γ is such that the amplitude of the combined output E ₃₄ is equal to the amplitude of the inputs E ₃ and E ₄ , and the phase is advanced by φ _s34 / 2 from the input E _3. It is set.

Next, the composite output E ₃₄ is input together with the inputs E ₃ and E _{4 in} FIG.
Is input to the electronic switch 650 as shown in FIG.

The electronic switch 650 control signal E _s5 formed by dividing the frequency dividing circuit 653 a control signal E _s2 from the pulse generating circuit described above, is switched by the time width T _0/2, the output line of the electronic switch 650 From 654 and 652, E ₃ and E ₃₄ , respectively, and outputs E ₃₄ and E ₄ whose phase angles are shifted by φ _s34 / 2 are output as outputs E ′ _A and E ′ _B , respectively.

Note that the signal generation circuits 62, 64 other than the signal generation circuits 61, 63,
65, the number of the fixed interpolation outputs is appropriately selected according to the magnitude of the phase difference between the pair of received outputs that are input to each other, similarly to the signal generation circuit 61 described above, and according to the selected number. The number of switching stages of the electronic switch and its switching period are appropriately selected, configured and operated.

The fixed interpolated output E ₁₁ to E ₁₈ in Figure 3 in the description of the signal generator circuit 61 (a) is, FIG. 4 (b), respectively alternately from reception output E _1, E ₂ as (c) It has been described as being formed. The purpose is as follows.

As shown in FIGS. 7 (a) and 7 (b), the vibrators 16, 17 at the ends of the group of transducers for forming the reception beam receive the signal S coming from the main axis direction of the reception beam. The respective outputs are E ₆ and E ₇ , the phase difference between the two outputs is φ _s , and the oscillators 16 and 17 arrive at the same phase but the signal wave S
And each E _N6, E _N7 a receive output of the oscillator 16, 17 by interference waves N to have a phase difference phi _N for.

Next, a fixed interpolation output E ' ₆ as shown in FIG.
If E has created a _{6 '7} is above E complete the phase phi ₆ from reception output E ₆ signal generating circuit and in the same manner', also from the reception output E ₇ phase phi ₇ delayed by E _'7 respectively , Received wave output
E _6, E each with the phase reception output E _6, E ₇ at the same time is being output interference output E _N6 of _7, E _N7 also phase angles respectively φ
_6, a is phi ₇ phase E _'N6, E' _N7.

The amplitude of the interpolation output Eo fixed interpolated output _{E '6,} E' ₇ is formed by combining after being attenuated by the damping ratio alpha = beta = 0.5, respectively and then are substantially equal to the amplitude of the received wave output E _6, E ₇ But,
The amplitude of the interpolation output E _No interference wave E _'N6, E' _N7 is similarly interpolated output _{E '6,} E' ₇ is smaller than the reception output E _N6, E _N7 of the interference wave as shown in FIG. .

In the case where interpolation is performed after phase-shifting the reception outputs of a pair having such a large phase difference, the signal-to-noise ratio during the interpolation is improved.

Next, the interpolation section 7 is composed of interpolation circuits 71 to 75 as shown in FIG. 1, and the interpolation circuit 71 is an attenuation circuit as shown in FIG.
711, 712, a frequency dividing circuit 713, and a combining circuit 714. The damping circuits 711 and 712 are provided with a damping ratio α from a control output E _s2 from a pulse generating circuit not shown in the drawing and a control output E _s4 formed by _{dividing the} frequency by a frequency dividing circuit 713, respectively.
And β is in the number of stages is appropriately selected during the time T _0/7, and with the increase or decrease in association while maintaining the complement function, time
T are set to change as follows for each _0/7. That is, at the first time _0- T0 / 7, α is from 100% to 0
To, beta is from 0 to 100%, then from 0 α is 100% at time _{T 0 / 7~2T 0/7,} β is a from 0 to 100%, the time
T _0/7 damping ratio for each alpha, is set so that β is repeatedly increases and decreases in opposite phases, respectively.

Therefore, as shown in FIG.
E _A and E _B are input to attenuation circuits 711 and 712, respectively,
multiplied by β and input to the synthesis circuit 714 as αE _A and αE _B ,
The result is synthesized and becomes the output E _o1 . The output E _o1, the phase angle phi _o1 to the output E _A damping ratio alpha, reciprocating repeatedly during the time T ₀ between the phase of the output E _B from the output E _A phase in accordance with the repetition of increase and decrease of β . As a result, the phase phi _c of the output E _o1 outputted from the interpolation circuit 71 changes from 0 to phi _s during the time T ₀ as shown in Figure 6 (4).

In the interpolation circuits 72 to 75 other than the interpolation circuit 71, similarly to the above-described interpolation circuit 71, the increase / decrease cycle of the attenuation ratio of the attenuation circuit is appropriately selected according to the time-dependent change of the time series output of the pair input thereto. Then, the attenuated output of each pair is appropriately configured and operated so as to be synthesized and output.

The signal generating circuit 61 and the interpolation circuit 71 as described above, from one side in the reception output of each pair, the output of any transducer of the turning direction of the reception beam, during the time T _0, each pair Are formed, and the output is attenuated for each output of the pair, and then combined to form and output each interpolation output.

Next, the interpolation circuit 71 is operated by the phase shift circuits 81 and 82 of the phase shift unit 8.
Each of the interpolation outputs from # 75 to # 75 is phase-shifted by a phase difference determined by the geometrical arrangement of the vibrator and output as an in-phase output. Next, the outputs of the same phase are combined by the combining circuit 9 in FIG.

As described above, the transducers 11 to 16 are selected by the electronic switch 2 from the transducer group of the transducer 1 in FIG. 1, and the respective reception outputs are taken out. The signal generator 6 forms an appropriate number of fixed interpolation outputs arranged for each appropriately selected phase difference with respect to the output of the pair of adjacent transducers, and these fixed interpolation outputs are alternated in the order of phase. is selected, is output as a time series output of each pair of time T ₀ width, then the output is synthesized for each pair after being attenuated to increase or decrease every appropriate time for each pair in the interpolation section 7. Further, the combined outputs are phase-shifted by the phase shifter 8 so that the phase difference based on the arrangement position of the transducers between the respective outputs is compensated, output in phase, and then combined in the combining circuit 9. Then, it is output as a turning receiving beam output.

(Effect of the Invention) As described above, if the present invention is applied to the scanning sonar, even if the phase difference between the pair of outputs from the adjacent vibrators is larger than the conventional one, the phase difference between the pair of outputs may be reduced. An appropriate number of fixed interpolation outputs are created and inserted, and then the fixed interpolation outputs are sequentially selected, and the interpolation is performed by appropriately increasing or decreasing the attenuation, thereby obtaining an interpolation output with a small amplitude change and a small phase shift. Therefore, when the diameter and the wavelength of the transducer are constant, the arrangement of the transducers is narrowed to form a sharp reception beam as in the related art, and the cost is not increased by increasing the number of reception channels. Further, it is not necessary to increase the diameter of the transducer in order to obtain a sharp receiving beam as compared with the related art, and there is an advantage that the influence on the ship speed due to the increase in the fluid resistance and the increase in fuel cost can be suppressed as compared with the related art.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.
FIG. 3 is a detailed block diagram of the signal generation circuit and the interpolation circuit in FIG. 1, FIG. 3 is a fixed interpolation output vector diagram, FIG. 4 is a circuit diagram of the phase shift circuit and a fixed interpolation output vector diagram in FIG. The figure shows a fixed interpolation circuit and its vector diagram,
FIG. 6 is a diagram for explaining the operation of the output signal of the signal generating circuit and the interpolation circuit and the output signal in FIG. 5, and FIG. 7 is a diagram showing the vibrator adjacent to the terminal of the vibrator group forming the receiving beam in the present invention. FIG. 8 is a block diagram showing the configuration of a conventional scanning sonar device, FIG. 9 is a detailed diagram of an interpolation circuit in FIG. 8, and FIG. FIG. 10 is an operation explanatory vector diagram of the interpolation circuit. 1 ... Transducer / receiver, 2 ... Electronic switch, 3 ... Interpolator,
4 ... Phase shift section, 5 ... Synthesis circuit, 6 ... Signal generation section, 7
... Interpolation unit, 8 ... Phase shift unit, 9 ... Synthesis circuit, 10-17 ...
... vibrator, 61-65 ... signal generation circuit, 71-75 ... interpolation circuit, 611 ... moving circuit, 620 ... electronic switch, 711,712
…… Attenuation circuit, 714 …… Synthesis circuit.

Claims (1)

(57) [Claims] A plurality of adjacent transducer groups are selected from a group of transducers arranged in a circle, and are sequentially switched. After the phases of the selected transducer outputs are made to be in phase, they are combined and synthesized. In a forming and swirling scanning sonar; from a pair of received powers from adjacent oscillators,
In the outputs formed by phase shifting, the respective amplitudes are equal to the amplitude of the received wave output, and the appropriate number arranged for each phase angle appropriately selected between the phase difference between the pair of received wave outputs Means for forming and outputting a fixed interpolation output of (i); between each pair of reception outputs, a pair of outputs arranged in the order in which the respective fixed interpolation outputs are inserted in the order of phase, and outputs a pair of outputs that are always in phase with each other. Means for alternately taking out outputs arranged alternately in phase at an appropriate period, and taking out and outputting the time width of the time series output of the pair to be taken out as the switching period of the vibrator; Means for providing a pair of time-series outputs with a pair of attenuations in which the amplitude of the output alternately increases and decreases in the opposite phase between 0 and 100%, and then combines and outputs the paired time-series outputs in each switching period when the series output is switched at the time of formation. And: combining each output after attenuation by a geometrical arrangement of each output. Circle then taken out through a phase shift circuit for compensating for the phase difference, combined with a means for outputting; scanning sonar receiving apparatus characterized by comprising a.