Development of a Multi-spectral and Polarimetric Technique for Anti-Submarine Warfare (ASW)

Passive electro-optical (EO) imaging of submerged submarines has been the subject of research for almost three decades. Previous efforts, which have focused on the use of passive, multi-spectral imaging methods to detect, classify, and localize submerged submarines, have been hampered by scene clutter and false alarms due to sea foam. Including polarization will enhance the multi-spectral techniques by splitting the signal content into polarized and unpolarized bands. This has the potential to increase detection performance by helping to isolate the surface clutter due to surface reflection of skylight from the scattering of sunlight by white water and the upwelling light from below the surface. Areté proposes to modify its previously developed and validated simulation and performance code to incorporate detailed knowledge of the multi-spectral, polarimetric sensor technology, with an emphasis on the Electro-Optic Passive ASW System (EPAS). The upgraded code will be used to conduct a rigorous, analytical assessment of the expected performance of a multi-spectral, polarimetric sensor suitable for use aboard either manned or unmanned aircraft conducting Non-Acoustic Anti-Submarine Warfare (NAASW) missions. Proof-of-concept field testing of the concept using such a sensor, which Areté is developing under another Navy contract, would be accomplished during Phase II.BENEFITS: The successful development of a passive, multispectral, polarimetric NAASW sensor will provide the Navy with the capability of detecting and tracking submarines without alerting the submarine to the presence of the searching platform. The multi-spectral, polarimetric (MSP) techniques will enhance the detection performance and reduce false alarms of existing and future systems by reducing surface clutter and false alarms due to sea foam. In addition, a sensor that successfully couples polarization measurements with multi-spectral data will permit operations that increase search rate over current multi-spectral techniques.