Underwater Vertical Electric Field Detection

Sonobuoys are used in marine surveillance to provide information regarding detection and classification of marine vessels by employing acoustic sensors. However, there are situations, particularly in littoral environments, in which the efficacy of acoustic sensors can be significantly compromised. In these instances, some level of performance enhancement may be possible by using supplementary sensing techniques such as electromagnetic sensing. Current electric-field sensors, used for detection and classification of marine vessels, collect only horizontal electric-field measurements. A sonobuoy capable of also collecting vertical electric field measurements would enable exploitation of all electric-field signals emanating from a submerged vessel. These signals may be particularly useful in environments in which the quality of acoustic data from traditional sonobuoys is compromised. QUASAR Federal Systems proposes to develop an innovative underwater E-field sensor appropriate for collecting vertical E-field measurements over a large effective aperture that can be integrated with sensors that measure the horizontal E-field components. The vertical E-field sensor will be a low-cost design suitable for scale-up to mass production. The E-field sensors developed in the present program will be integrated into a standard sonobuoy in collaboration with Ultra Electronics Undersea Sensor Systems Inc (USSI) and validated and tested in an open ocean environment.