METHOD OF MEASUREMENT OF ACOUSTIC SIGNAL REFLECTION FACTOR Russian patent published in 1994 - IPC

FIELD: determination of complex factor of reflection of acoustic signals from surface of materials under examination. SUBSTANCE: simultaneous radiation of a.f. and r.f. amplitude-modulated radio pulses by an acoustic radiator positioned at the end of hydroacoustic tube, the phases and frequencies of a. f. filling and envelope of the pulses coincide, reception by hydrophone, located in the middle of the tube, of radio pulses propagating from the radiator and reflected from specimen placed at the end of the tube opposite to the radiator, measurement of amplitude of a.f. radio pulse propagating from the radiator, measurement of amplitude of a.f. radio pulse reflected from specimen, determination of the ratio of amplitudes of ratio pulses reflected from specimen and propagating from the radiator equal to the modulus of deflection factor, detection of amplitude-modulated radio pulses reflected from specimen and received by receiver, separation of modulation-frequency signal from detected radio pulse, measurement of difference of phase between sinusoidal filling of reflected a.f. radio pulse and sinusoidal filling of detected amplitude-modulated radio pulse reflected from specimen, equal to the phase of reflection factor. EFFECT: enhanced accuracy of measurement of reflection factor phase. 2 dwg