JPH0693022B2 - Directivity forming device in horizontal linear receiver array - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a directivity forming device in a horizontal linear receiver array used underwater.

[Conventional technology]

Conventionally, this type of device is disclosed, for example, in Japanese Patent Application No. 59-38652 and Japanese Patent Application No. 58-176369, and the directivity pattern formed is a conical shape symmetrical about the array axis. It was

[Problems to be solved by the invention]

The conventional device has a drawback that it is not possible to form a directional pattern having azimuth angles of 360 ° around the entire circumference because of the above structure. Further, the directivity pattern oriented in the array axis direction has a drawback that an imaginary direction is generated in the opposite direction when the receiver spacing is close to the half wavelength of the sound wave.

SUMMARY OF THE INVENTION It is an object of the present invention to eliminate the defects of the directivity pattern formed by this horizontal linear receiver array and to provide an apparatus capable of independently monitoring the azimuth angle of 360 ° around the entire circumference.

[Means for solving problems]

A directivity forming device for a horizontal linear receiver array having a plurality of horizontal linear receivers composed of an omnidirectional receiver and a pair of directional receivers. , Directivity forming means for obtaining an output having a plurality of cardioid directivities having azimuth angles different from each other as an azimuth angle of the zero by combining the outputs of the directional receivers, and the output of the directivity forming means. , A multi-beam forming means for collecting each azimuth angle of the zero point and inputting it to a phaser to obtain a multi-beam, and a standby phasing angle of the phaser, which is symmetrical with respect to the azimuth angle of the zero point with respect to the array axis. Angle adjusting means for directing the azimuth angle.

〔Example〕

FIG. 2 is an explanatory view of a structural example of a horizontal linear wave receiver array to which the directivity forming device of the present invention is applied, and FIG. 3 is a perspective view of a structural example of the wave receiver pair of FIG. FIG. 4 is an explanatory diagram of the directivity pattern of each receiver of FIG.
An array similar to the 652 embodiment is constructed. In FIG. 2, 1 to 7 are receiver pairs of an omnidirectional receiver and a directional receiver, which are connected by a cable 8 and horizontally extended in the sea between the sea surface 9 and the seabed 10. ing. FIG. 3 shows a structural example of a pair of receivers 1 to 7, 11 is an omnidirectional receiver, and 12 is a directional receiver having a cosine and sine pattern. FIG. 4 shows the directivity of the horizontal plane when viewed from above the receiver pair of FIG. 3, and FIG. 4 (a) shows the directivity of the omnidirectional receiver 11,
(B) and (c) show the directivity of the cosine output and the sine output of the directional receiver 12. In FIG. 4, the 0 ° axis represents the azimuth angle of the wave receiver pair 7 when viewed from the center point of the array in FIG. 1, that is, the position of the wave receiver pair 4, and the angle θ is set counterclockwise.

FIG. 1 is a block diagram showing an embodiment of the present invention H1 to H7.
Are the same cardioid formers and are connected to the outputs of receiver pairs 1-7. T1 to T12 are phasing devices for forming a beam for standby monitoring, and this output is a beam output directed at each azimuth angle of 360 ° around the circumference. Next, these connections are such that the omnidirectional output of receiver pair 1 is connected to terminal A1, the cosine directional output is connected to terminal B1, and the sine directional output is connected to terminal C1. The outputs of the wave receiver pair 7 are connected to the A2, B2, C2 terminals and the A7, B7, C7 terminals.

FIG. 5 is a cardioid generator H1 in the block diagram of FIG.
It is a block diagram for explaining the configuration of H7, input terminals A, B, C
Correspond to A1 to A7, B1 to B7 and C1 to C7 in FIG. 1, respectively. The fifth output terminals N1, N2, ... N12 are respectively 1N in FIG.
Corresponds to 1,7N1,1N2 to 7N2, ..., 1N12,7N1,2. Reference numeral 13 is an adder and 14 is a weighting coefficient unit, and the value of the weighting coefficient is the value shown in FIG. In the connection of FIG. 5, the line of the omnidirectional terminal A is directly applied to each of the twelve adders 13, and the lines of the cosine and sine directional terminals B and C are the weighting coefficient unit 14 of the values of FIG. And is applied to the adder 13 via. Adder
13 is provided to form a cardioid type directivity as shown in FIG. 7, and the azimuth angle of the zero point of the cardioid pattern is 0 ° in FIG. 7, but the cosine and By giving an appropriate weighting factor to the sine-directional signal, the signal can be directed to an arbitrary azimuth angle as shown below.

Letting the cardioid type directivity function be Φ (θ) and the azimuth angle of the zero point, these are related by the following equation (1).

The case of Φ (θ) = 1-cos (θ−) (1) = 0 ° is the cardioid pattern in FIG. 7. It is easy to see that the zero point of the pattern faces the azimuth angle of ° when =. When the expression (1) is expanded using a trigonometric function, the following expression (2) is obtained.

Φ (θ) = 1-cos (θ−) = 1−cos · cos θ−sin · sin θ (2) From the equation (2), a cosine directivity signal has a −cos weighting factor and a sine directivity It can be seen that a cardioid pattern in which the zero point is oriented in the azimuth angle can be obtained by adding a -sin weighting factor to the signal and adding it to the omnidirectional signal.
The values of the weighting factors for providing twelve zero points at azimuth angles of every 30 ° of 360 ° on the entire circumference as shown in FIG. 8 are shown in FIG. The configuration of FIG. 5 uses an operational amplifier for the adder 13,
It is easily understood that the weight coefficient unit 14 can be easily realized by using an input resistor.

In the connection of Fig. 1, from 0 ° to 360 obtained in this way
The output N1 of the cardioid generator with the zero point in the azimuth angle
With respect to N12, each of the seven wave receiver pairs is input to the phase adjusters T1 to T12. That is, terminal 1N1 is 1P1, 2N1 is 1P2, and 3N1 is P
3, ..., 6N1 is connected to 1P6, 7N1 is connected to 1P7, zero point is 0
The cardioid directional signals of the wave receiver pairs 1 to 7 oriented in the azimuth angle of ° are input to the phasing device T1 and phasing in the phasing device T1 in the 180 ° direction, and output to the terminal 1. Similarly, terminal 1N2 is 2P1
2N2 to 2P2, 3N2 to 2P3, 6N2 to 2P6, 7N2 to 2
Connected to P7, the cardioid directional signals of the receiver pairs 1 to 7 with the zero point in the direction of 30 ° are input to the phaser T2,
The phasing device T2 performs phasing in the direction of 330 ° and outputs it to the terminal Y2.
With the same connection, the cardioid directional signals of the wave receiver pairs 1 to 7 with the zero point oriented in the 60 ° direction are input to the phaser T3,
The phasing device T3 performs phasing in the 300 ° direction and outputs it to terminal Y3. The relationship between the azimuth of the zero point of the cardioid directivity of the input of the phase adjusters T1 to T12 and the phasing azimuth is as shown in FIG.
The azimuth angle is symmetrical with respect to the array axis. FIG. 10 is a diagram for explaining the delay times in the phase adjusters T1 to T12. When the phase adjusting azimuth θ = 30 °, the string AB passing through the wave receiver pair 4 and perpendicular to θ = 30 ° is used. The receiver pairs 1 to 7 are time-delayed and added so that they are in phase on the line. When the phasing azimuth θ = 330 °, a delay is applied so as to be in phase on the string CD line, and the time delay applied to the receiver pairs 1 to 7 is the same as on the string AB line, so , T2 and T12 are the same phaser.
This relationship is shown in the remarks column of FIG. As can be seen from the explanation of FIG. 9, for example, in the case of a terminal Y2 output having a phasing angle of 330 °, a conical directivity in the directions of 30 ° and 330 ° is usually formed due to the symmetry of the array. By the connection shown in FIG. 1, signals having a cardioid directivity zero pointed at 30 ° were collected and phased, so that a directivity pattern in which the directivity was directed only at an azimuth angle of 330 ° could be obtained. Phased azimuth angle 180
In the case of the terminal Y1 output of ゜, the imaginary azimuth occurs in the direction of 0 ° when the receiver spacing is close to the half-wavelength of the sound wave, but the signal with the zero point of the cardioid directivity pointing to 0 ° is collected to perform phasing. Because I did
It is possible to obtain a directivity pattern in which the directivity is only 180 °.

First, only the omnidirectional receiver is used to form and monitor a directional pattern symmetrical with respect to the array axis, and then the outputs of the cosine directional and sine directional receivers are used for symmetry with respect to the array axis. In the method of eliminating such uncertainties, the monitoring ability is inferior because the entire monitoring time is not fully utilized. Furthermore, the method of switching the monitoring azimuth angle of a single beam over time instead of the multi-beam, which constantly waits for 360 ° around the entire circumference, is similarly inferior in monitoring capability. The present invention is
It is an object of the present invention to provide a directivity forming device capable of fully exerting its ability by always using all the output signals of the receiver.

In the above explanation, the number of pairs of receivers is 7, and the number of phasing directions is all around.
It was performed for 12 cases at every 30 °, but it is needless to say that it is not limited to this. As a block diagram, a cardioid former was first installed, and then a phasor was installed, but conversely, first, omnidirectional, cosine directivity, and sine directivity, each of seven acoustic signals were provided. 21 phaser is used in 7 directions in every 30 ° between 0 ° and 180 °, and then the device output for phasing in the 0 ° direction is 180 degrees.
The cardioid former output toward 30 ° is used as the output, and the device output for phasing in the 30 ° direction is the cardioid former output directed toward 330 °. The device output for phasing in the 330 ° direction is the zero toward 30 °. As the output of the cardioid shaper to be directed, as in the case of FIGS. 1, 5 and 6 below, a cardioid directivity is formed, and 12 beam outputs are provided at azimuth angles of 30 ° for 360 °. It can be easily understood that the obtained block diagram configuration can be realized. Furthermore, if the acoustic signal is digitized and treated by using an analog / digital converter, the block diagram of FIG. 1 can be realized by arithmetic processing using a microprocessor.

〔The invention's effect〕

As described in detail above, according to the present invention, in the directivity forming device in the horizontal linear receiver array, the zero point of the cardioid directivity is set to an azimuth angle symmetrical to the array axis of the phasing azimuth angle. I erased the imaginary direction towards, so 360 around
There is an advantage that a beam can be formed that awaits an azimuth angle of °. Further, since it is always waiting for 360 ° all around, there is an advantage that a phasing output capable of monitoring all around can be provided without causing any loss in the given acoustic signal. Furthermore, since cardioid directivity is added to the same array structure, the directivity gain can be improved by 3 dB.

[Brief description of drawings]

1 is a block diagram of an embodiment of the present invention, FIG. 2 is an explanatory view of the structure of a horizontal linear wave receiver array, FIG. 3 is a perspective view of a structure example of a wave receiver pair, and FIG. Illustration of directivity of the receiver,
FIG. 5 is a block diagram of the cardioid formers H1 to H7 in FIG. 1, FIG. 6 is a diagram showing the values of the weighting factors in FIG. 5, and FIG.
FIG. 8 is a diagram for explaining the cardioid directivity, FIG. 8 is a diagram for explaining the azimuth angle at every 30 ° of the entire circumference, and FIG. 9 is a diagram for explaining the relationship between the azimuth angle of the zero point of the cardioid directivity and the alignment azimuth angle. FIG. 10 and FIG. 10 are diagrams for explaining the delay times of the phase adjusters T1 to T12 in FIG. H1, H2, H3, H4, H5, H6, H7 ... cardioid former, T1, T2,
T3, T4, T5, T6, T7, T8, T9, T10, T11, T12 …… Phaser, 13 ……
Adder, 14 ... Weighting coefficient unit.

Claims (1)

[Claims] 1. A directivity forming device for a horizontal linear receiver array having a plurality of horizontal linear receivers each comprising an omnidirectional receiver and a pair of directional receivers. Directivity forming means for obtaining an output having a plurality of cardioid directivities having azimuth angles different from each other as an azimuth angle of the zero by combining the output of the directional receiver and the output of the directional receiver; The output of the directivity forming means is collected for each azimuth angle of the zero point and is input to the phase adjuster to obtain a multi-beam, and the standby phase adjusting angle of the phase adjuster is set with respect to the array axis. A directivity forming device in a horizontal linear wave receiver array, comprising: an angle adjusting means for directing an azimuth angle symmetrical to an azimuth angle of a zero point.