a transmit transducer for coupling a swept frequency acoustical wave to a test material;

a sweep generator for supplying a frequency swept signal to said transmit transducer, said sweep generator comprising:

means for specifying a plurality of amplitude values of a signal which define each cycle of a swept wave for a swept frequency range having a start frequency and end frequency; and,

means for continuously producing said amplitude values defining each cycle of said swept wave at a controlled rate, whereby a series of amplitude values are sequentially produced defining each cycle constituting said swept wave;

a receive transducer coupled to receive an acoustical wave from said material and produce an electrical signal in response thereto; and

a digital processing device for storing said electrical signal representing an amplitude and phase of a spectral response to said swept frequency acoustic wave.

Abstract: An apparatus and method for performing ultrasonic spectroscopy provides for rapid evaluation of test materials with good amplitude, balanced response at all test frequencies. A swept frequency signal is generated which is applied to a transmit transducer coupled to a test part. A receive transducer provides a detected signal that is fully digitized for real-time or post signal processing. The created swept frequency signal can be equalized from data obtained from direct coupling between transmit and receive transducers. The resultant data is analyzed for amplitude and/or phase information as a function of frequency and can be used to analyze filter characteristics, identify resonances, characterize material signatures and many other applications.

U.S. Class: (73/628) (73/602)

IPC: (G01N 29/04)

US Patents Cited: 3224253 3948345 4271705 4285241 4428235 4512194 4539847 4577503 4581935 4704905 4758964 4819649 4829823 4949313 5062296 5099848 5191795 5303590 5426979

OG Section: Electrical