Summary of Freddex Developments Prior to At-Sea Phase.

Abstract : The long range objective of exercises such as FREDDEX, Front and Eddy Exercise, is the capability to predict the environmental influences in an ocean basin on acoustic array performance through remote sensing of ocean features and environmental and acoustic models. The performance, resolution, and combined source locating ability of a high-resolution mid-frequency towed array, and conventional systems, as influenced by extensively studied strong mesoscale features are the total objective of FREDDEX. The effects of a Gulf Stream ring on the MF towed array will be investigated through measurements of beam splitting and width, side lobe suppression, and array distortion. Measurements will be made which will assist in developing and improving environmental and stochastic acoustic models. Also, remote sensing of ocean features by over-the-horizon radar and satellites will be tested with ground truth measurements.