ANALYSIS OF PHASE CHARACTERISTICS OF SOUND WAVE SPHERICALLY CONVERGING AND GENERATED BY PARAMETRIC ANTENNA

Abstract

As part of this work, experimental studies were carried out aimed at understanding the processes of nonlinear interaction of acoustic waves. The object of the study was a parametric antenna, which used a weakly bent converter to generate pump waves. Both the amplitude and phase characteristics of the sound field generated by focusing pump transducers, which play an important role in the operation of parametric antennas, have been studied. Of particular interest is the phenomenon that occurs in focus: here the pumping waves that initially propagate to the center (spherically converging) change their direction to the opposite (spherically diverging). This transition is accompanied by a 180-degree change in the oscillation phase. Analysis of the obtained data describing the phase and amplitude properties of such sonar emitters showed that in the region distant from the source (far zone), the spatial characteristics of the interaction of ultrasonic waves are like those observed in antennas using a convex pump converter. The key conclusion of the experimental studies was the establishment that parametric radiating antennas form an acoustic field with a uniform phase structure in the entire region where the interaction of pumping waves occurs. The basic principles that determine the formation of such a field were also identified.

Due to their advantages, such as stable phase characteristics, wide bandwidth, lack of side lobes and compact dimensions, parametric antennas with focusing pump converters can be successfully used in measuring parametric emitters for hydroacoustic measurements.