Abstract: A plurality of sensing modules are deployed by positioning thereof in spaced relation to each other on a seafloor surface at a shallow depth to establish a targeted seawater zone within which certain conditions are detected, such as those produced by the presence of a sea vessel such as a submarine within the targeted zone. Data signals are generated within the deployed sensing modules in response to said detection of the submarine for radio frequency transmission above the seawater targeted zone from floating transmitters ejected from the sensing modules positioned on the seafloor surface after detection of the submarine.

Abstract: At a ship's magnetic silencing facility, calibration measurements are taken of onboard magnetic fields, and the off-board magnetic signature is minimized through an iterative degaussing process. Current data associated with the signature minimization is retained by a processor-controller implemented, along with degaussing coils and other apparatus, in a CLDG system effectuated onboard in a manner continually adaptive to changing conditions while voyaging. According to the CLDG methodology: Real time measurements are taken of the onboard magnetic fields, and are modified to account for the degaussing coils' magnetic effects. Via least squares fit mathematics, scale factors are calculated based on the relationship between (i) the real time measurements (as modified) of the onboard magnetic fields and (ii) the calibration measurements of the onboard magnetic fields.