Bearing Stake Coherence and Array Signal Gain Area Assessment Report
Abstract
This report assesses the coherence data taken during BEARING STAKE, a major acoustic survey conducted in the Northwestern Indian Ocean from January through May 1977. The survey was designed to provide (1) acoustic data to determine variability in the acoustic environment, (2) inputs to performance models, and (3) acoustic data for assessing surveillance options in selected areas of the Northwestern Indian Ocean. During BEARING STAKE measurements were made for determining the array phase coherence and the array signal gain for long, horizontal line arrays receiving multipath signals from long-range, narrowband, low-frequency towed CW sources in the Northwestern Indian Ocean. A bottom-mounted and two mid-depth towed arrays were used. The phase coherence and the array signal gain results for these arrays are presented and compared. Since the Northwestern Indian Ocean is usually bottom-limited and the sound-speed profiles are complex in small-scale structure at mid-depths a considerable rangewise variability exists in the phase coherence and the array signal gain for this multipath environment. This variability increases due to the presence of irregular bottom slopes as well as seamounts. This variability is the dominant characteristic of this body of water when the performance of long horizontal acoustic arrays is considered.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1978
- Accession Number
- ADC018803
Entities
People
- J. A. Neubert