Patent ID: 6155116
Filing Date: 2000-12-05
Classification: G01N

Abstract:
A method of acoustic testing, comprising the steps of:providing a free-field acoustic environment;disposing an acoustic treatment to be tested in said free-field acoustic environment;generating a gated acoustic pulse from a source within said free-field acoustic environment, said gated acoustic pulse being of a frequency of interest;focusing said gated acoustic pulse at said acoustic treatment, wherein said gated acoustic pulse is partially reflected from said acoustic treatment as reflected energy in said free-field acoustic environment;measuring acoustic pressure of said gated acoustic pulse focused at said acoustic treatment from a location approximately in-line with said source and said acoustic treatment, said location being at least one-half wavelength of said frequency of interest away from said source and being at least a distance equal to (t*c/2) away from said acoustic treatment where t is equal to the duration of said gated acoustic pulse and c is equal to the speed of sound in said free-field acoustic environment;measuring acoustic pressure of said reflected energy at said location; andcomparing said acoustic pressure of said reflected energy to said acoustic pressure of said gated acoustic pulse as an indication of performance of said acoustic treatment at said frequency of interest.