The Analytic Signal Magnitude for Improved Ultrasonic Signatures

dc.contributor.author Gammell, Paul
dc.date 2018-02-13T18:40:46.000
dc.date.accessioned 2020-06-30T01:29:36Z
dc.date.available 2020-06-30T01:29:36Z
dc.date.copyright Thu Jan 01 00:00:00 UTC 1981
dc.date.embargo 2013-12-06
dc.date.issued 1981-08-01
dc.description.abstract <p>Conventional pulse-echo ultrasonic receivers rectify the received signal. Because the signature of the reflecting interfaces is modulated by the predominant ultrasonic frequency, interpretation of this signal in terms of the structure of the reflecting interfaces is difficult. Smoothing, as by an R-C filter, ameliorates this effect, giving a less confusing display at the expense of resolution. The magnitude of the analytic signal, on the other hand, represents the shape of the energy packets arriving from the reflecting interfaces. Since this signature is free of modulation effects, interpretation of the signal in terms of the reflecting interfaces is more straightforward. Furthermore, smoothing is not normally needed. The analytic signal magnitude can be obtained by several means. The implementation used in this study is particularly suited for digital data processing. The Hilbert Transform of the received signal (the "real part") is obtained with the aid of the Fast Fourier Transform. This produces the quadrature component (the "imaginary part"). The magnitude is calculated from both these components. In contrast to signal processing techniques involving deconvolution, this technique is surprisingly robust with respect to noise and quantization. Typical signatures obtained with this technique are demonstrated.</p>
dc.format.mimetype application/pdf
dc.identifier archive/lib.dr.iastate.edu/cnde_yellowjackets_1981/84/
dc.identifier.articleid 1083
dc.identifier.contextkey 4894529
dc.identifier.s3bucket isulib-bepress-aws-west
dc.identifier.submissionpath cnde_yellowjackets_1981/84
dc.identifier.uri https://dr.lib.iastate.edu/handle/20.500.12876/16227
dc.language.iso en
dc.relation.ispartofseries Interdisciplinary Program for Quantitative Flaw Definition Annual Reports
dc.source.bitstream archive/lib.dr.iastate.edu/cnde_yellowjackets_1981/84/1981_YellowJacket_083_Gammell_AnalyticSignal.pdf|||Sat Jan 15 02:10:45 UTC 2022
dc.subject.disciplines Materials Science and Engineering
dc.subject.keywords Nondestructive Evaluation
dc.title The Analytic Signal Magnitude for Improved Ultrasonic Signatures
dc.type article
dc.type.genre 16_applications
dspace.entity.type Publication
relation.isSeriesOfPublication 43920e40-d127-4f4c-9087-dc709815fe7f
File
Original bundle
Now showing 1 - 1 of 1
Name:
1981_YellowJacket_083_Gammell_AnalyticSignal.pdf
Size:
184.27 KB
Format:
Adobe Portable Document Format
Description:
Collections