Wave Theory Corrections to Ray Theory Predictions of Average Long-Range Propagation.
Abstract
This study of corrections to propagation predictions based on ordinary ray theory is motivated by the problem of low-frequency ambient noise caused by surface shipping. Shipping noise is caused by many sound sources, widely distributed in range and azimuth from any receiver. The sources - propellers and machinery - are near the sea surface, at depths where large gradients of the sound speed are often found. These circumstances can lead to significant errors in calculations of low-frequency sound propagation based on ordinary ray theory. The objective of this study is to quantify the significant errors in ray theory calculations, and to indicate when they arise and how corrections may be made in the calculation of low-frequency shipping noise.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1977
- Accession Number
- ADA043378
Entities
People
- J. C. Heine
- P. W. Smith Jr.
Organizations
- BBN Technologies