Accession Number:

ADA574800

Title:

Performance of Passive and Active Sonars in the Philippine Sea

Descriptive Note:

Annual rept.

Corporate Author:

MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF MECHANICAL ENGINEERING

Report Date:

2012-09-30

Pagination or Media Count:

9.0

Abstract:

We have the long term goals of understanding several aspects of passive and active sonar performance in the Philippine Sea when there is a robust environmental characterization of the sea floor and water column plus accurate sourcereceiver positions. The particular objectives for this year was to examine the characteristics of the convergence zone CZ at the experiment. 1 We found very abrupt transitions into the CZ. Not all CZ s focus , i.e. sharp edges as we observed in the Philippine Sea. This feature has been noted in Brekhovskikh where he noted that such zones tend to remain clustered for many CZ s. 3 We are concerned with the width of the transitions as well as the stability of signals once a receiver is within a CZ. These factors have significant implications for source localization at CZ ranges. 2 We have analyzed the broadband complex envelope coherence of a sequence of LFM signals while on a constant range over paths with an excess depth to determine the impact, if any, of changes in the sound speed profile. The Philippine Sea experiments for acoustics and signal processing were executed in two separate cruises in April-May 2009 and in July 2011. There were many source-receiver configurations over the time of the experiment. In 2009 multichannel data were recorded on the FORA Five octave research array HLA horizontal line array towed by the RV Kilo Moana and the DVLA Deep Vertical Line Array moored VLA vertical line array.

Subject Categories:

  • Physical and Dynamic Oceanography
  • Acoustic Detection and Detectors

Distribution Statement:

APPROVED FOR PUBLIC RELEASE