RU1810861C - Method of control of parametric radiation directional pattern - Google Patents

Abstract

The invention relates to hydroacoustics and can be used to control the beam width (LH) of parametric antennas. The purpose of the invention is the formation of energy-efficient parametric radiation with the desired shape of the beam, increasing the efficiency of controlling the shape of the beam and its stability over time. In the region where the pump waves interact, the parametric emitter generates a layer of gas bubbles with increased acoustic nonlinearity by electrolysis on a two-transparent electrically conductive electrode. The thickness of the electrode is selected to be less than a quarter of the pump wavelength in it. In order to give the necessary shape to the DN, the surface of the electrode is curved. 2 ill. 5 yo

Description

The invention relates to sonar and can be used to control the radiation pattern of parametric antennas.

The aim of the invention is the formation of energy-efficient parametric radiation with the desired shape of the beam, increasing the efficiency of controlling the shape of the beam and its stability over time.

In FIG. 1 is a block diagram of an apparatus for implementing the method; in FIG. 2 - time diagrams of the operation of the device:

The method includes the following operations: forming in the far zone of the irradiator a uniform bubble layer by electrolysis of water on a soundproof electrically conductive plate and irradiating the formed bubble layer with pump waves.

An apparatus for implementing the method comprises: 1 - a synchronizer; 2 - delay circuit; 3, 4 — shaper of rectangular pulses; 5 - generator of harmonic oscillations; 6 - modulating oscillator; 7 - balanced modulator; 8 - pulse modulator; 9 - power amplifier; 10 - acoustic pump transducer; 11 - a constant voltage source; 12 - pulse modulator; 13 - DC amplifier; 14, 15 - electrolysis electrodes.

The device operates as follows.

The trailing edges of the sync pulses start a delay circuit. 2, which generates video pulses I2 of duration Tzad equal to the time interval necessary to achieve the maximum sound pressure in the wave of the differential frequency

about

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flow (HFC), which is formed when pumping waves pass through gas bubbles formed on the plates. The second edges of the 4 pulse pulses 4 also start at the trailing edges of the clock pulses. It generates the video pulses I4 of duration r equal to the duration of the pulse voltage applied to the electrolysis electrodes. At the output of the balanced modulator 7, amplitude-modulated oscillations with suppressed carrier are generated, which after pulse modulation in the modulator 8 are emitted into the water by the acoustic pump transducer 10. Using a constant voltage source 11 and a second pulse modulator 12, the pulse voltage is applied to the electrodes 14 and 15, forming increased non-linearity on the electrode due to the release of gas bubbles.

Claims (1)

SUMMARY OF THE INVENTION A method for controlling directivity of parametric radiation, comprising 25 5 0 5 introducing into the interaction region of the initial pump waves of the bubble layer with increased parameters of acoustic nonlinearity and the attenuation coefficient of the pump waves and irradiating it with pump waves, characterized in that. in order to generate energy-efficient parametric radiation with the desired radiation pattern, increase the speed of controlling the radiation pattern and its stability in time, the bubble layer is formed by electrolysis on a sound-transparent conductive electrode with a thickness of not more than a quarter of the pump wavelength by applying pulsed to the electrode current with a given amplitude and duty cycle, and the electrode is bent to form a given shape of the radiation pattern. with the required radius of curvature, set it on the axis of the parametric sound source perpendicular to it, and the second electrode of the electrolysis pair is placed above the first electrode.  TO fa & ./. fi e. 2