JPH0123748B2 - - Google Patents

Description

Detailed Description of the Invention (Technical Field of the Invention) This invention extracts ultrasonic signals arriving from a specific direction from among ultrasonic signals arriving from various directions underwater, and This invention relates to a device that sequentially changes direction.

The applicant has filed a patent application for this type of device in 1982.
No. 121439 (Japanese Unexamined Patent Publication No. 126271/1983). This invention further develops this to realize a practical device.

(Prior art) Patent application filed in 1982 by the applicant as a conventional device
-121439 (Japanese Unexamined Patent Publication No. 59-126271) will be explained.

In FIG. 1, Z ₁ to Z ₆₄ indicate ultrasonic transducers, which are spaced at regular intervals in a straight line, for example, 1/1/2 of the transducer signal.
They are arranged at two wavelength intervals.

The received signals of each of the vibrators Z ₁ to Z ₆₄ are amplified by the respective preamplifiers PA ₁ to PA ₆₄ , and then guided to mixing circuits MX ₁ to MX ₆₄ provided correspondingly.

Each of the mixing circuits MX ₁ to MX ₆₄ separately performs mixing with the rectangular wave train read out from the storage circuit 1.
Note that the rectangular wave train is described in Japanese Patent Application No. 57-121439
59-126271), counter 2
A clock pulse source 4 is sent out from a frequency dividing circuit 3.
When counting pulse trains, the data at the memory address corresponding to the count value is read out, and data changes corresponding to changes in the count value are used as a rectangular wave train. Further, this rectangular wave train data is latched into each of the latch circuits 601 to 664 by a latch pulse sent from the latch pulse generator 5.

The mixed outputs of the mixing circuits MX ₁ to MX ₆₄ are added in an adding circuit 7, and then a specific frequency signal is extracted by a filter 8. Therefore, the special application was filed in 1983.
As explained in No. 121439 (Japanese Unexamined Patent Publication No. 59-126271), ultrasonic transducer Z ₁ Of the received signals in each direction arriving at Z ₆₄ , a received signal in a specific direction can be sent out from the filter 8 . Furthermore, by changing the phase of the rectangular wave train sent out from the memory circuit 1 to a specific state, that is, by changing the frequency of the rectangular wave train, the azimuth of the azimuth signal sent out from the filter 8 is changed. be able to.

The output signal of the filter 8 is amplified by an amplifier 9 and then led to a display 10 for display. The display 10 is, for example, a cathode ray tube display, and a scanner 11 scans the display screen. The scanner 11 performs a scanning operation at the same time as the transmitter 12 sends out a transmission pulse. Further, the transmitter 12 is the transmitter 1
At the same time as the ultrasonic pulse is transmitted from the counter 3, the counter 2 is also driven at the same time.

In Fig. 1, the filter 8 is an ultrasonic transducer.
The received signals of Z ₁ to Z ₆₄ are combined and a received signal in a specific direction is sent out. At this time, the azimuth resolution of the received signal, and therefore the directivity angle of the received beam, is determined by the array length of the ultrasonic transducers, and the directivity angle can be sharpened as the number of transducers increases. can. For example, when 64 oscillators are arranged every 1/2 wavelength as shown in Fig. 1, a receiving beam with a directivity angle of 2° is obtained. In addition, if you want to obtain a receiving beam with a directivity angle of 1°, it is 1/2.
It is sufficient to arrange 128 oscillators for each wavelength.

However, in Fig. 1, each oscillator Z ₁ to
Since a rectangular wave train for mixing must be generated for each received signal of Z ₆₄ , if 64 transducers are arranged, 64 types of rectangular wave trains must be prepared. Therefore, the memory circuit 1 must have a very large memory capacity. For example, in order to obtain a received signal with a distance resolution of 50cm, it is necessary to use 666.6μsec.
By changing the frequency of the rectangular wave during this period as explained in Japanese Patent Application No. 121439/1982 (Japanese Patent Application No. 126271/1982), the receiving beam can be changed within a desired range angle. Therefore, if we use a 250KHz rectangular wave train and output one cycle with an accuracy of 1/32, the time per step is 1/250 x 10 ³ x 1/32 = 125 (n sec). Therefore, the number of steps required for 666.6 μsec is 666.6/125×10 ^-3 ≒ 5333 (steps), and since the memory circuit 1 requires a storage capacity of at least 5333 bits for each rectangular wave train, 64
In order to generate various types of square waves, 64 memory circuits with a memory capacity of 5333 bits are required.

(Object of the Invention) The present invention realizes a device similar to the above by using the minimum necessary memory circuit without using a large number of memory circuits as described above.

(Embodiment of _the invention) In FIG _. 2, Z ₁ to Z ₆₄ indicate ultrasonic transducers similar to those in FIG. It is led to mixing circuits MX ₁ to MX ₆₄ .

Reference numeral 14 denotes a memory circuit, which, similarly to FIG. 1, sends out rectangular wave train data in response to changes in the count value of the counter 15. Eight types of rectangular wave train data are sent out. This rectangular wave train data is latched by latch circuits 161 to 168, and eight types of rectangular wave trains as shown in FIG. 3 are sent out from the latch circuits ₁₆₁ to ₁₆₈ . The frequencies of the rectangular wave trains Q ₁₁ to Q ₁₈ change by a specific amount while maintaining a specific phase relationship depending on the data output of the storage circuit 14. The phase relationship and frequency change in this case are shown in Japanese Patent Application No. 57-121439.
As explained in JP-A-59-126271, data is written in the memory circuit 14 so as to occur during the time Ts required to change the directivity direction of the received beam by a predetermined angle.

The rectangular wave trains Q ₁₁ to Q ₁₈ sent out from the latch circuits 16 ₁ to 16 ₈ are guided to each of the mixing circuits MX ₁ to MX ₈ , and are separated from the received signals of the ultrasonic transducers Z ₁ to Z ₈ , respectively. mixed with

The mixed signals of the mixing circuits MX ₁ to MX ₈ are added together in an adding circuit 17 ₁ and then guided to a filter 18 ₁ where a specific frequency signal is extracted from the mixed frequency signals. Therefore, as a result of rectangular wave sequences Q ₁₁ to Q ₁₈ maintaining a specific phase relationship and their respective frequencies changing by a specific amount in time Ts, the ultrasonic transducers Z ₁ to Z ₈
The direction of directivity of the composite received signal can be changed by an angle corresponding to the change in frequency, and the composite received signal is sent out from the filter ₁₈₁ .

Similarly, the rectangular wave trains Q ₁₁ to Q ₁₈ sent out from the latch circuits 16 ₁ to 16 ₈ are also guided to the mixing circuits MX ₉ to MX ₁₆ , respectively, and the ultrasonic transducers Z ₉ to Z _16.
are mixed with each received signal. Mixed circuit MX ₉ to
After each mixed signal of the MX ₁₆ is added by an adder circuit 17 ₂ , a specific frequency signal is extracted by a filter 18 ₂ . Therefore, like the filter 18 ₁ , the filter 18 ₂ sends out a composite reception beam from the ultrasonic transducers Z ₉ to Z ₁₆ , and the direction of the composite reception beam is aligned with the ultrasonic transducers Z ₁ to Z. It changes within a predetermined range angle in conjunction with _{the 8} combined receiving beams.

Similarly, the rectangular wave trains Q ₁₁ to Q ₁₈ sent out from the latch circuits 16 ₁ to 16 ₈ are transmitted to the mixing circuit.
MX ₁₇ to MX ₂₄ MX ₂₅ to MX ₃₂ , MX ₃₃ to
MX ₄₀ , MX ₄₁ to MX ₄₈ , MX ₄₉ to MX ₅₆ ,
Mixed with each of MX ₅₇ to MX ₆₄ . and,
The mixing output of each mixing circuit is the addition output, which is the addition circuit 17.
After addition in each of ₃ to 17 ₈ , specific frequency components are extracted by respective filters 18 ₃ to 18 ₈ .

Therefore, each of the filters 18 ₁ to 18 ₈ is
A composite reception signal of every eight ultrasonic transducers Z ₁ to Z ₆₄ is sent out. The directivity direction of each received beam changes in conjunction with the frequency change of the rectangular wave train sent out from the latch circuits 16 ₁ to 16 ₈ .

Note that in the above, the counter 15 counts the pulse train led from the clock pulse source 19 via the 1/2 frequency divider circuits 20 and 21, _{and
168 to 168} transmit a rectangular wave train by latching the data in the memory circuit 14 using the latch pulse of the latch pulse generator 22. The latch pulse generator 22 generates a latch pulse using the input pulse and output pulse of the frequency divider circuit 21, as explained in Japanese Patent Application No. 121439/1983.

As described above, the filters 18 ₁ to 18 ₈
The receiving beam sent out in conjunction with the mixing circuit 2
It leads to each of 3 ₁ to 23 ₈ . Mixing circuit 23 ₁
The receiving beam signals of the filters 18 ₁ to 18 ₈ and the rectangular wave trains sent out from each _of the latch circuits 24 ₁ to 24 ₈ are mixed separately.

The latch circuits 24 ₁ to 24 ₈ latch the stored data read out from the storage circuit 25 and perform the operation as shown in _FIG.
A rectangular wave train shown in _Q28 is transmitted. Note that the latch circuits 24 ₁ to 24 ₈ are the latch pulse generation circuit 3.
The latch operation is performed using the latch pulse No. 5, and the latch pulse generating circuit 35 generates the latch pulse using the input pulse and output pulse of the frequency dividing circuit 20. The memory circuit 25 has eight output terminals, and outputs rectangular wave train data to the eight output terminals in accordance with the count value of the counter 26.

This rectangular wave train data consists of rectangular wave trains Q ₂₁ to Q ₂₈ sent out from latch circuits 24 ₁ to 24 ₈ .
Similar to the rectangular wave sequences Q ₁₁ to Q ₁₈ , each has a specific phase relationship and each frequency changes by a specific amount in time Ts.

The mixed outputs of the mixing circuits 23 ₁ to 23 ₈ are added in an adding circuit 27 and then guided to a filter 28 to extract a specific frequency component.

As a result of the above, each of the filters 18 ₁ to 18 ₈ sends out phase synthesis outputs corresponding to equal phase wavefronts indicated by B ₁ to B ₈ as shown in FIG. The equal-phase wavefront B ₁ is generated by phase-combining the received signals of the ultrasonic transducers Z ₁ to Z ₈ . The equal phase wavefront _B2 is generated by phase-combining the received signals of the ultrasonic transducers _Z9 to _Z16 . Similarly, equiphase wavefronts B ₃ , B ₄ , B ₅ , B ₆ , B ₇ ,
_B8 is generated by phase-combining the received signals of eight of the ultrasonic transducers _Z17 to _Z64 . Then, the filter 28 further converts the received signal phase-combined into the equal-phase wavefronts B ₁ to B ₈ into equal-phase wavefronts B ₀
Send out the phase-combined output. In other words, the rectangular wave trains sent out from the latch circuits 24 ₁ to 24 ₈
The phase relationships of Q ₂₁ to Q ₂₈ are set so that the received signals represented by the equal phase wavefronts B ₁ to B ₈ have the same phase on the equal phase wavefront B ₀ .

The direction of the equal-phase wavefronts B ₁ to B ₈ changes in response to the frequency change of the rectangular wave sequences Q ₁₁ to Q ₁₈ . Then, the equiphase wavefront B ₀ also has a rectangular wave sequence Q ₂₁ to
Equiphase wavefront B ₁ to B ₈ corresponding to the frequency change of Q ₂₈
The direction of the equal-phase wavefront changes in conjunction with the change in direction. Therefore, the ultrasonic transducer is transmitted from the filter 28.
A receiving beam signal is transmitted that phase-combines the receiving signals of Z ₁ to Z ₆₄ to form a receiving beam in a specific direction, and changes the pointing direction of the receiving beam within a predetermined range of angles. .

The received signal extracted by the filter 28 is amplified by an amplifier 29 and then guided to a display 30 for display. Pixel scanning of the display 30 is performed by a scanner 31 in the same manner as in FIG.
2. Further, at the same time that the ultrasonic pulse is transmitted from the transmitter 33 by the transmitter 32, the counter 15 and the counter 26 start counting operations. At this time, counter 15 starts counting from an initial value in response to a transmission trigger from transmitter 32, whereas counter 26 starts counting based on a preset value from preset circuit 34.

In the preset circuit 34, a numerical value is set to compensate for the phase delay of the signal caused by the filters ₁₈₁ to ₁₈₈ . That is, the memory address of the memory circuit 25 is designated by the count value of the counter 26, and a rectangular wave train is sent out as the count value changes. Therefore, by changing the count start value, the phase of the rectangular wave train can be changed. Therefore, by appropriately setting the values of the preset circuit 34 and adjusting the phases of the rectangular wave trains _Q21 to _Q28 , the phase delay of the signals caused by the filters ₁₈₁ to ₁₈₈ can be compensated for, resulting in the output shown in FIG. Thus, the phases of the received signals represented by the equal-phase wavefronts B ₁ to B ₈ can be accurately matched on the equal-phase wavefront B ₀ .

Further, in the above, the counter 26 counts the output pulses of the frequency dividing circuit 20, while the counter 15 further counts the output pulses of the frequency dividing circuit 20 by 1/1.
Count the pulse train whose frequency is divided into two. The counters 15 and 26 both measure the time during which the directed direction of the extracted receiving beam changes within a predetermined range angle.
The counting capacity is set for Ts so that the counted values are in order.

Therefore, the counter 26 has twice the counting capacity as the counter 15, and the memory circuit 25 also has twice the number of memory addresses as the memory circuit 15. Thereby, the phase precision of the rectangular wave trains Q ₁₁ to Q ₁₈ and Q ₂₁ to Q ₂₈ generated by the memory circuits 14 and 25 is maintained at the same precision.

For example, the received signals of ultrasonic transducers Z ₁ to Z ₆₄ are
150KHz, and the rectangular wave train sent out by the latch circuits ₁₆₁ to ₁₆₈ is 250KHz, and when each of the filters ₁₈₁ to ₁₈₈ extracts a sum component of 400KHz of the mixed frequency signal, it is mixed by the mixing circuits ₂₃₁ to ₂₃₈ . The rectangular wave trains Q ₂₁ to Q ₂₈ require a frequency signal of about 600 KHz. Therefore, if you set it like this,
Since the wavelength of the rectangular wave trains Q ₂₁ to Q ₂₈ is 1/2 that of the rectangular wave trains Q ₁₁ to Q ₁₈ , one wavelength of each rectangular wave train can be set to the same phase accuracy, for example, one wavelength to 1/32. The wave height data of each divided section is divided into storage circuits 14 and 25.
In this case, the memory circuit 25 needs to have at least twice the memory capacity of the memory circuit 14.

(Effect of the invention) As is clear from the above, the memory circuits 14 and 25
generates eight types of rectangular wave trains Q ₁₁ to Q ₁₈ and Q ₂₁ to Q ₂₈ , respectively, and a receiving beam similar to that shown in FIG. 1 is formed by these 16 types of rectangular wave trains. Therefore, the number of types of rectangular wave trains can be significantly reduced compared to the prior art, and the number of memory circuits can also be sufficiently reduced.

(Other Embodiments of the Invention) FIG. 6 shows another embodiment, in which parts with the same numbers as in FIG. 2 perform the same operations.

In FIG. 6, adder circuits 171 to 178 perform addition operations in the same manner as in FIG. 2, and adder circuits 171' to 178' perform addition operations in the same manner as their corresponding adder circuits. That is, the adder circuit 171' adds the same signals as the adder circuit 171, and the adder circuit 172' adds the same signals as the adder circuit 172, and
Addition circuits 173', 174', 175', 176',
177', 178' are adder circuits 173, 174, 1
Addition operations are performed in the same manner as in each of 75, 176, 177, and 178.

The addition outputs of the addition circuits 171' to 178' are led to filters 181' to 188', and like the filters 181 to 188, specific fixed components are extracted. Therefore, the filters 181 to 188 and 181' to 188' have equal phase wavefronts as shown in FIG.
A pair of reception beam signals indicated by B ₁ to B ₈ are each transmitted. And filters 181 to 1
The extracted signals of filters 181' to 188' are guided to mixing circuits 231' to 238', while the extracted signals of filters 181' to 188' are guided to mixing circuits 231' to 238'.

Mixing circuits 231 to 238 are latch circuits 24 ₁
A mixing operation is performed in the same manner as in FIG. 2 using the rectangular wave trains Q ₂₁ to Q ₂₈ (FIG. 4) sent out from the waveforms Q 21 to 24 ₈ (FIG. 4). On the other hand, the mixing circuits 231' to 238' perform a mixing operation using the rectangular wave trains sent out from the latch circuits 241' to 248'. The latch circuits 241' to 248' send out rectangular wave trains Q ₂₁ to Q ₂₈ similar to the latch circuits 241 to 248. and,
The latch circuits 241' to 248' are the memory circuits 25'.
The stored data is read out by the counter 26' and a rectangular wave train is sent out. The memory circuit 25' and counter 26' are the same as in FIG.
It operates similarly to the counter 26 and sends out rectangular wave sequences Q ₂₁ to Q ₂₈ . Furthermore, counters 26 and 2
6' has a count value preset by respective preset circuits 34, 34', and counters 26, 34'.
By presetting the count value of 26', the phase of the rectangular wave trains sent out by the latch circuits 241 to 248 and the rectangular wave trains sent out by the latch circuits 24 ₁ ' to 24 ₈ ' can be arbitrarily changed.

The mixed outputs of the mixing circuits 23 ₁ to 23 ₈ are added in an adding circuit 27 and then guided to a filter 28 to extract specific frequency components. In FIG. 2, the filter 28 sends out a received signal corresponding to the equal phase wavefront B ₀ , but in FIG.
The phases of the rectangular wave sequences Q ₂₁ to Q ₂₈ , and therefore the preset values of the preset circuit 34, are set so that the equal phase wavefront B ₀₁ differs from B ₀ by Δθ.

On the other hand, the mixed outputs of the mixing circuits 23 ₁ ′ to 23 ₈ ′ are added by an adding circuit 27 ′ and then guided to a filter 28 ′ to extract a specific frequency component. The preset circuit 34' is set so that the equal-phase wavefront _B02 sent out by the filter 28' differs from the equal-phase wavefront _B01 of the filter ₂₈ by Δθ in the opposite direction from the equal-phase wavefront B0 of FIG. There is. Then, the received signal of the equal-phase wavefront B ₀₁ sent out by the filter 28 and the received signal of the equal-phase wavefront sent out by the filter 28' are multiplied by each other in the multiplication circuit 36.

Therefore, as shown in FIG. 7, the directional characteristic of the received signal sent out by the filter 28 is _M1 , and the directional characteristic of the received signal sent out by the filter 28' _{is M2.}
Assuming that M ₁ and M ₂ have different directivity directions by 2Δθ, the multiplication output emphasizes the common portion of the directivity characteristics M ₁ and M ₂ , as shown in M ₁₂ .
That is, by multiplying the received signal with the directional characteristic M ₁ and the received signal with the directional characteristic M ₂ , a directional characteristic M ₁₂ with a very sharp directional angle compared to the directional angles of the directional characteristics M ₁ and M ₂ can be obtained. Can be done. As is clear from the above, the directional angle of the directional characteristic M ₁₂ is the same as that of the directional characteristic M ₁ .
The optimum angle can be set by adjusting the difference angle 2Δθ of the pointing direction of M ₂ .

The received signal with the directivity characteristic M ₁₂ sent out from the multiplication circuit 36 is amplified by the amplifier 29 and then sent to the display 30
will be displayed. Pixel scanning of the display device 30 is performed by a scanner 31 in the same manner as in FIG. 2, and the scanner 31 performs a scanning operation by a transmitter 32. Further, the transmitter 32 transmits the ultrasonic pulse from the transmitter 33 and at the same time, the counters 15 and 2
6 and 26' are operated, and the count values of the counters 26 and 26' change based on the respective preset values of the preset circuits 34 and 34'.

As a result of the above, in Fig. 6, the received signals shown by the directivity characteristics M ₁ and M ₂ in Fig. 7 are formed with slightly different directional directions, and a common received signal for each is detected. By this, a received signal with a sharp directivity angle as shown by the directivity characteristic _M12 is detected. The directivity angle of the received signal indicated by the directivity characteristics M ₁ and M ₂ is determined by the array length of the ultrasonic transducers Z ₁ to Z ₆₄ . Therefore, by multiplying the received signals with the directional characteristics M ₁ and M ₂ to form a received beam with a sharp directional angle as shown in the directional characteristic M ₁₂ , the ultrasonic transducers Z ₁ to
It is possible to obtain the same effect as increasing the array length by increasing the number of Z ₆₄ arrays. For example, in FIG. 7, the deviation angle of the pointing direction is 2Δθ so that the directivity angle of the receiving beam with the directional characteristic _{M 12} is 1/2 of the directivity angle of the receiving beam with the directional characteristics M ₁ and M 2. is set, the array length of ultrasonic transducers Z ₁ to Z ₆₄ is set to 2
You can get the same effect as doubling it.

In FIG. 6, the multiplication circuit 36 is designed to multiply the output signals of the filters 28 and 28', but a correlation circuit is used instead of the multiplication circuit to multiply the common output signals of the filters 28 and 28'. Alternatively, a signal may be detected.

In addition, in FIG. 1 or 2, there are eight sets of first-stage synthesis circuits that combine the received signals of 64 ultrasonic transducers with the received signals of eight ultrasonic transducers, and this first stage. 2 of the second stage synthesis circuit that synthesizes the synthesis circuit output
Although it is synthesized by a stage synthesis circuit, 3 stages, 4 stages
The synthesis may be performed using a synthesis circuit having one or more stages. For example, when synthesizing using a three-stage synthesis circuit, if the number of oscillators is 64,
The first-stage combining circuit is formed by 16 sets of combining circuits that combine the received signals of four transducers each, and the second-stage combining circuit is formed by combining the combined outputs of the 16 sets of the first-stage combining circuit into four sets.
It is formed by four sets of synthesis circuits that are synthesized one by one, and these four
Each of the combined outputs of the second-stage combining circuit of the set may be combined by the third-stage combining circuit.

[Brief explanation of drawings]

FIG. 1 shows a conventional device, FIG. 2 is an embodiment of the present invention, FIGS. 3 and 4 are waveform diagrams for explaining its operation, and FIG. 5 is for explaining the output signal of the filter. , and FIG. 6 show another embodiment, and FIG. 7 shows a diagram for explaining the directivity characteristics of the received signal. In FIG. 2, Z ₁ to Z ₆₄ ... ultrasonic transducers,
PA ₁ to PA ₆₄ ... Preamplifier, MX ₁ to MX ₆₄ ...
... Mixing circuit, 14 ... Memory circuit, 15 ... Counter, 16 ₁ to 16 ₈ ... Latch circuit, 17 ₁ to 17 ₈ ... Addition circuit, 18 ₁ to 18 ₈ ... Filter, 19 ... Clock pulse source, 20 and 2
1... Frequency dividing circuit, 22... Latch pulse generation circuit, 23 ₁ to 23 ₈ ... Mixing circuit, 24 ₁ to 2
4 ₈ ...Latch circuit, 25...Memory circuit, 26...
... Counter, 27 ... Addition circuit, 28 ... Filter, 29 ... Amplifier, 30 ... Display, 31
... Scanner, 32 ... Transmitter, 33 ... Transmitter,
34... Preset circuit, 35... Latch pulse generator.

Claims (1)

[Claims] 1 K ultrasonic transducers (K=m×n, m and n are both integers) are arranged in a straight line, and the received signals of the K ultrasonic transducers are synthesized. In a device for extracting an incoming wave signal in a specific direction, the K ultrasonic transducers are divided into n groups of m pieces each, and the received signals of the m transducers are synthesized for each group to identify the n sets of first synthesis circuits for extracting arriving wave signals in different directions;
a first mixed signal generation unit that sends out m types of mixed signals, each of which is synthesized separately with the received signal of each vibrator, and whose phase is regulated so that the synthesized signal is directed in a specific direction; a second combining circuit that further combines the output signals of the first combining circuits of the n sets to extract signal components in the specific direction; and a first combining circuit of the m sets guided by the second combining circuit; each separately mixed with the synthesis output of the synthesis circuit, and
a second mixed signal generator that sends out n types of mixed signals, each phase of which is regulated so that the second synthesis circuit extracts a signal component in the specific direction; m sets of mixing circuits, each of the combining circuits separately mixing the mixed signal of the first mixed signal generator and the m oscillator reception signals;
a filter that extracts a specific frequency signal from the composite signal of the mixed signals of the m sets of mixing circuits;
The second combining circuit includes n sets of mixing circuits that individually mix each combined output of the first combining circuit and the mixed signal of the second mixed signal generator, and the n sets of mixing circuits. and a filter that extracts a specific frequency signal from the composite signal of the mixed signal, and the filter extracts the specific direction by changing the phase of the mixed signal of the first and second mixed signal generators in conjunction with each other. A device for controlling the pointing direction of a received beam. 2 K ultrasonic transducers (K = m x n, m and n are both integers) are arranged in a straight line, and the received signals of the K ultrasonic transducers are synthesized to generate incoming waves in a specific direction. In the signal extraction device, the above K ultrasonic transducers are divided into n groups of m pieces each, and for each group, the received signals of the m transducers are combined to extract an incoming wave signal in a specific direction. n sets of first synthesis circuits, and m of each set commonly led to the n sets of first synthesis circuits
a first mixed signal generation unit that sends out m types of mixed signals, each of which is mixed separately with the received signal of each vibrator, and whose phase is regulated so that the combined signal is directed in a specific direction; a second combining circuit that further combines the output signals of the n sets of first combining circuits and extracts a signal component in substantially the same direction as the specific direction; each separately mixed with the composite output of the first composite circuit of the set, and
a second mixed signal generator that sends out n types of mixed signals, the phases of each of which are regulated so that the second combining circuit extracts signal components in substantially the same direction as the set direction; a third synthesis circuit that further synthesizes the output signals of the n sets of first synthesis circuits in the same way as the circuit and extracts a signal component in substantially the same direction as the specific direction; are separately mixed with the composite outputs of the n sets of first composite circuits, and
a third mixed signal generator that sends out n types of mixed signals whose phases are regulated so that the third synthesis circuit extracts signal components in substantially the same direction as the specific direction; a multiplier circuit that multiplies the extracted signals of the three combining circuits, and each of the n sets of first combining circuits multiplies the mixed signal of the first mixed signal generator and the received signal of the m transducers. m mixing circuits each separately mixing the
first and second frequency signals for extracting first and second specific frequency signals from the composite signal of the mixed signals of the m sets of mixing circuits;
and a filter circuit, and the second mixing circuit includes n sets of mixing circuits each separately mixing the output of the first filter circuit and the mixed signal of the second mixed signal generator, and the n sets of mixing circuits. and a filter that extracts a specific frequency signal from the mixed signal of the circuit, and the third combining circuit separately mixes the output of the second filter circuit and the mixed signal of the third mixed signal generator. Consisting of n sets of mixing circuits and a filter that extracts a specific frequency signal from the mixed signals of the n sets of mixing circuits, the phase of the mixed signals of the first, second, and third mixed signal generators is mutually adjusted. At the same time as changing the specific direction to be extracted by changing it in conjunction,
The mixed signals of the second and third mixed signal generators are slightly shifted in phase in opposite directions to the mixed signals of the first mixed signal generator. By making a difference, the second
The azimuth of the extraction signal of the synthesis circuit and the azimuth of the extraction signal of the third synthesis circuit are slightly different, and the extraction signals of the second and third synthesis circuits are multiplied by the multiplication circuit, thereby increasing the azimuth resolution of the extraction signal. 1. A receiving beam pointing direction control device characterized in that the received beam direction control device improves. 3. The wave receiving device according to claim 2, wherein the multiplication circuit includes a correlation circuit that detects a coincidence between the extracted signal of the second combining circuit and the extracted signal of the third combining circuit. Beam direction control device.