JPS61222398A - Wave transmitter-receiver - Google Patents

Abstract

PURPOSE:To obtain a detection signal or an arrival signal with regulated signal intensity within a prescribed angle by arranging plural vibrators with the same spacing on a straight line and impressing or taking out a signal having amplitude that is regulated by a specified curve or the position of the vibrator. CONSTITUTION:A reference amplitude signal (a) is supplied to each of electrodes 11-14 from the intermediate terminal 16 of a transformer 5. The signals having the amplitudes (b) and (c) that is represented as the function (sinx)/x of a distance (x) are supplied to the electrodes 8 and 9 of the vibrators 2 and 3 respectively and to the electrodes 7 and 10 of the vibrators 1 and 4 respectively. As the result, the intensity of the signal emitted from a wave transmitter-receiver is regulated within a prescribed angle theta0 and a directional characteristic shown at figure B is obtained. As for the receiving of the arrival signal, when the arrival signal with the same amplitude is received by the vibrators 1-4, the signal having the amplitude (b) based upon the signal that is acquired by the vibrators 2 and 3 and also, the signal having the amplitude (c) based upon the signal that is acquired by the vibrators 1 and 4 are transmitted to the primary side 15 of the transformer 5. As the result, the arrival signal that is acquired by a receiving beam having the characteristic shown at the figure B is outputted from the primary side of the transformer 5.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) This invention relates to a transducer with improved directional characteristics. This transducer emits a detection signal so that the signal strength within a predetermined angle can be approximately constant,
Further, signals arriving from within a predetermined angle can be received with substantially constant sensitivity.

(Prior Art) The directivity characteristics of a conventional transducer are shown in Fig. 5, and it is not possible to emit a detection signal such that the signal strength within the directivity angle is constant, and it is difficult to emit a detection signal such that the signal intensity within the directivity angle is constant. It was not possible to receive the signal with a certain sensitivity. In conventional transducers, for example, a detection signal of the same amplitude is applied to the entire surface of the electrode of a vibrator.

(Problems to be Solved by the Invention) When a conventional transducer having a directional characteristic as shown in FIG. 5 is used in an underwater detection device, for example.

When a reflected signal from an object to be detected captured using this transducer is displayed on a display, the surroundings of the image are not clearly displayed and are displayed indistinctly. Another problem is that when the amplification degree of the receiver that amplifies the captured reflected signal is changed, the size of the image changes, making it impossible to accurately determine the size of the object to be detected.

(Means for solving the problem) A plurality of transducers are arranged at approximately equal intervals on a straight line, and ing is fixed for each transducer by the - curve and the position of the transducer! The structure is configured to apply signals with the same amplitudes or to extract signals with these amplitudes from each vibrator.

(Example) FIG. 1 shows an embodiment of the invention.

FIG. 2 shows the relationship between the signal applied to the electrode of the vibrator shown in FIG. 1 or the signal taken out from the electrode of the vibrator and the directional characteristic of the vibrator.

FIG. 3 shows another embodiment of the invention.

FIG. 4 shows a signal supplied to or extracted from the vibrator shown in FIG. 3.

In FIG. 1, piezoelectric vibrators 1, 2, 3.4 have the same specifications and are arranged at equal intervals on a straight line. The primary side of the transformer 5 is supplied with a pulse signal whose carrier frequency is amplitude-modulated with a constant amplitude of, for example, 50 KHz. One end of the secondary winding 6 of the transformer 5 is connected to the upper electrode 8.9 of the oscillators 2 and 3, and the other end is connected to the upper electrode 8.9 of the oscillators 1 and 4.
The intermediate terminal IB is connected to the upper electrode 7.10 of the lower electrodes 11, 12, 13 .
14 in common.

Figure 2 (A) shows each vibrator 1.2, which constitutes the transducer.
3.4, and FIG. 2(B) shows the directivity characteristics of the transducer.
, 3.4 is the length of the above electrodes, ON is the wavelength of the carrier frequency signal, and θ is the azimuth angle. Supplied on 11, 12, 13 and 14. A signal with an amplitude of b is supplied to the electrode 8.8 of the vibrator 2.3, and a signal with an amplitude of C
A signal having an amplitude of is applied to the electrode 7.10 of the vibrator 1.4. Note that the interval d between adjacent vibrators is set to >d.

As a result, it has been confirmed in experiments that the intensity of the signal emitted from the transducer becomes constant at a predetermined angle .theta.-, that is, a directivity characteristic as shown in FIG. 2(B) is obtained.

Next, the case of receiving an incoming signal will be explained.

When incoming signals of the same amplitude are received by transducers 1, 2, and 3.4, the signal with the amplitude shown in FIG. Based on the signals sent to the primary winding 15 and captured by the oscillators l and 4, a signal with an amplitude C in the figure is transmitted to the primary side 15 of the transformer 5, and the electrodes 11 and 12 of each oscillator are
, 13 and 14, a signal with amplitude a shown in the figure is transmitted to the primary side of the transformer 5. As a result, the incoming signal captured by the receiving beam having the directional characteristics shown in FIG. 2(B) is output from the primary side of the transformer 5.

In FIG. 3, piezoelectric vibrators 30 to 37 have the same specifications and are arranged at equal intervals on a straight line.

The primary side of the transformer 38 has a carrier frequency of, for example, 50K.
A pulse signal that is amplitude modulated with a constant amplitude pulse of Hz is supplied. One end of the secondary winding 33 of the transformer 38 is
connected to upper electrodes 43, 44 of vibrators 33 and 34;
The other end is connected to the upper electrode of the vibrators 32 and 35,
The intermediate terminal 60 is connected to the upper electrodes of the vibrators 31 and 36, the intermediate terminal 61 is connected to the upper electrode of the vibrators 3o and 37, and the other intermediate terminal 82 is connected to the upper electrodes of the vibrators 30 to 37 that constitute the transducer. It is commonly connected to the lower electrodes 50 to 57 of 37.

A reference amplitude signal a is supplied from an intermediate terminal 82 of the lance 38 to the lower electrodes 50 to 57 of the vibrators 30 to 37. A signal with an amplitude of b is supplied to the upper electrodes of the transducers 33 and 34, a signal with an amplitude of C is supplied to the upper electrodes of the transducers 32 and 35, and a signal with an amplitude of d is supplied to the upper electrodes of the transducers 31 and 34.
and 36, and a signal having an amplitude of e is supplied to the upper electrodes of vibrators 30 and 37. In addition,
Each of the vibrators 30 to 37 is arranged such that the distance d between adjacent vibrators is d×λ.

As a result, it is possible to obtain a directional characteristic that allows the intensity of the signal emitted from the transducer to be constant at a predetermined angle θ-, as shown in FIG. 2(B). According to this embodiment, a directional characteristic with steeper rise and fall than the directional characteristic shown in FIG. 2(B) can be obtained.

Next, the case of receiving an incoming signal will be explained.

When incoming signals of the same amplitude are received by each of the transducers 30 to 37 constituting the transducer, a signal of the amplitude shown in FIG. A signal of amplitude C in FIG. d, and a signal of amplitude e in the same figure based on the signals received by the transducers 30 and 37, and based on the output signals of the lower electrodes 50-57 of each transducer 30-37. A signal with amplitude a shown in the figure is transmitted to the primary side of the transformer 38. As a result, the incoming signal captured by the receiving beam having the directional characteristics as shown in FIG. 2(B) is output from the primary side of the transformer 38.

In this example, eight piezoelectric vibrators were used, but the number is not limited to this, and an even number of four or more vibrators may be used. It is sufficient to supply a signal with an amplitude determined by the position of the vibrator and the negative signal curve value, and to extract a signal having these amplitudes from each vibrator at the time of reception.

FIG. 6 shows another embodiment of the invention.

FIG. 7 shows another embodiment of the invention.

Hereinafter, parts assigned the same reference numerals as those used in the above embodiments perform the same functions.

The signal generator 80 has a carrier frequency of, for example, 200K)Iz
A pulse signal amplitude-modulated with a constant amplitude pulse is sent to the phase shifter 91.11+2.93.1114. Each of the phase shifters 81 to B4 includes a delay circuit composed of, for example, an inductor and a capacitor, and can vary the amount of phase shift of the signal. The output signals of phase shifters 81-84 are supplied to corresponding amplifiers 88-88. Each amplifier is configured to be able to vary its amplification degree. The output signals of the amplifiers 88-88 are transmitted to the corresponding ultrasonic transducers 1-
4 and is launched into the water. The piezoelectric vibrators 1 to 4 are arranged at equal intervals on a straight line.

The amount of phase shift of the signals of all phase shifters 91-84 is set to the same amount, for example, zero, and the output signal of signal generator 80 is supplied to all amplifiers 86-89 without phase shifting.

The amplifiers 97 and 88 supply signals whose amplification degrees are appropriately adjusted and whose amplitudes are b shown in FIG. 2 to the vibrators 2 and 3. Amplifiers 86 and 89 supply signals whose amplitudes are C shown in FIG. 2 to vibrators 1 and 4. The transducers 1 to 4 are simultaneously excited by the supplied signals, and as a result, the intensity of the signal is kept constant at a predetermined angle θa as shown in FIG. It is possible to form a transmission beam having a directional characteristic that can be Furthermore, if the signal phase shift amount of each phase shifter 91 to 94 is set to a predetermined amount, the wavefronts sent out from all the oscillators can be tilted at a predetermined angle with respect to the above straight line, as is well known. It is possible to form a transmission beam having the directivity characteristics shown in FIG. 2(B) in any direction from 0 to 180 degrees with respect to the above straight line.

In FIG. 7, piezoelectric vibrators 1 to 4 are arranged at equal intervals on a straight line. Each of the amplifiers 101 to 104 is configured such that its amplification degree can be variably set. Phase shifters 106-109 are connected to corresponding amplifiers 101-109.
For example, it is composed of an inductor and a capacitor so that the output signal of 104 can be phase-shifted by an arbitrary amount.

Incoming signals of the same amplitude are received by transducers 1-4, and amplifiers 102 and 103 send signals having amplitude b shown in FIG. 2(A) to phase shifters 107 and 108. Amplifiers 101 and 104 send signals having amplitudes of C shown in FIG. 2(A) to phase shifters 10B and 109. When setting the signal phase shift amount of all the phase shifters 10B-109 to the same amount, for example, to snow, all the phase shifters 106 to 109
By combining the output signals, a receiving beam having the directivity characteristics shown in FIG. 2(B) can be formed in a direction perpendicular to the straight line. Furthermore, when the signal phase shift amount of each phase shifter 108 to 109 is set to a predetermined amount, a received wave having the directional characteristics shown in FIG. 2(B) in any direction from 0 to 180 degrees with respect to the above straight line A beam can be formed.

In addition, in FIG. 6 and FIG. 7, the case where four vibrators are used is explained, but the present invention is not limited to this.
It is also possible to use six or more transducers, in which case each transducer is supplied with a signal having an amplitude determined by the negative signal curve and the position of the transducer,
Or you can take it out from each vibrator.

Note that when applying or extracting a signal with a predetermined amplitude to each of the transducers 30 to 37 shown in FIG. 3, a signal having the amplitude shown in FIG. By supplying a signal with shelf width i shown in the same figure to oscillators 30, 31, 38, and 37 via a transformer, a transmission beam can be formed, or conversely, a signal with an amplitude of , i or j from corresponding predetermined transducers 30 to 37 and combine them to form a receiving beam. In this case, more ideal directivity characteristics can be obtained than those shown in FIG. 2(B).

In addition, in the above embodiment, an electrostrictive vibrator was used, but
The same purpose and effect can be obtained by using a magnetostrictive vibrator.

(Effects of the Invention) As described above, the present invention emits a detection signal such that the signal strength within a predetermined directivity angle can be made constant with a simple configuration, and also detects signals arriving from within this directivity angle. It is possible to provide a transducer having directional characteristics that can receive with a certain sensitivity.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the invention. FIG. 2 is a diagram showing the relationship between the signal applied to the electrode of the vibrator shown in FIG. 1 or the signal taken out from the electrode of the vibrator and the directional characteristic of the vibrator. FIG. 3 shows another embodiment of the invention. FIG. 4 is a diagram showing a signal supplied to the vibrator shown in FIG. 3 or a signal taken out from the vibrator. FIG. 5 shows the directivity characteristics of a conventional transducer. Figure 6 shows
This is another embodiment of this invention. FIG. 7 shows another embodiment of the invention.

Claims (1)

[Claims] (1) A plurality of transducers are arranged at approximately equal intervals on a straight line, and a signal with an amplitude determined by the curve of sinx/x and the position of the transducer is applied to each transducer, or a signal with an amplitude determined by the sinx/x curve and the position of the transducer is applied to each transducer. A transducer characterized by extracting amplitude signals.