METHOD OF DETERMINING ACOUSTIC FREQUENCY CHARACTERISTICS OF SOUND-ABSORBING STRUCTURES Russian patent published in 2017 - IPC G01H17/00 

FIELD: metrology.

SUBSTANCE: invention relates to metrology and hydroacoustics. Method involves radiation of a broadband signal, its reflection and reception. Received signal, which is obtained by summation with a signal reflected from sample of sound-absorbing structure and with multiple false reflections from walls, is subjected to temporary compression. Temporary compression of signal is performed using dispersion delay of received signal with subsequent correction of its phase spectrum. Continuous signals acquire shape of pulse signals, from which by strobing pulse acoustic signal reflected from sample of sound-absorbing structure is selected. Then reflected signal is restored by reverse phase correction. For determining acoustic frequency characteristics of sample of sound-absorbing structure, spectral analysis of selected signal is performed. Device comprises a signal generator, radiator arranged in a pool together with analysed sample, a receiver. Device also comprises a dispersion delay unit, a selection unit, a unit for restoring signal, a computing device, a recorder.

EFFECT: technical result is providing simultaneous measurement of reflection coefficient in low-frequency range.

1 cl, 7 dwg