Abstract
Propagation measurements made of high-amplitude periodic signals generated by the Army Research Laboratory’s Mobile Acoustic Source (MOAS) demonstrate greater energy at high harmonics relative to linear predictions, suggesting the possible influence of nonlinear effects (see Downing et al. [J. Acoust. Soc. Am. 116, 2517 (2004)]). An arbitrary-waveform version of an Anderson-type algorithm has been developed in order to compare numerical predictions with the measured MOAS spectra. In general, results demonstrate good agreement between predicted and measured spectra out to 375 m. However, comparisons at greater distances (approximately 1 km) and also for measurements made later in the afternoon exhibit less agreement. For these cases, the Anderson calculations generally overpredict the amount of high-frequency energy present in the measurements. Probable causes for these discrepancies include the effects of propagation at grazing incidence over a finite-impedance ground as well as increased atmospheric turbulence. [Work supported by the Strategic Environmental Research and Development Program.]
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
