title: Inaccuracy in the treatment of multiple-order diffraction by secondary-edge-source methods.
abstract: Existing secondary-edge-source methods based on the Biot-Tolstoy solution for diffraction from an infinite wedge compute multiple-order diffraction by cascading the integration over secondary sources used to determine first-order diffraction from the edge. It is demonstrated here that this approach errs in some important cases because it neglects slope-diffraction contributions. This error is illustrated by considering the case of an infinite slit in a thin, hard screen. Comparisons with measurements for this case and analytical solutions for the case of a circular aperture in a thin, hard screen are used as a basis to gauge the magnitude of the error.
authors.affiliation: Applied Research in Acoustics LLC, 1222 4th Street SW, Washington, DC 20024-2302, USA. jason.e.summers@ariacoustics.com
authors.forename: Jason E
authors.initials: JE
authors.lastname: Summers