Abstract: The invention as disclosed is an autonomous magnetic measurement system for monitoring the background magnetic fields associated with power lines, electronic devices, electronic vehicles and the Earth's background magnetic field. The components of the autonomous magnetic measurement system include a series of three axis analog magnetic sensors, a fluxgate compass, and a programmable micro-controller. The micro-controller receives data from the sensor and compass and is programmed to autonomously detect magnetic signals having particular characteristics of interest.

Abstract: An apparatus for effecting propagation of electromagnetic waves, comprising a hull outer surface, a dielectric material disposed over the hull outer surface, and an electrically conductive member embedded within the dielectric material. When a liquid medium contacts the dielectric material, the liquid medium, the hull outer surface, the dielectric material and the electrically conductive member cooperate to provide a waveguide through which electromagnetic waves can propagate wherein the boundaries of the waveguide are defined by the liquid medium and the hull outer surface. A sensor network can be provided within the dielectric material for receiving power and transmitting information.

Abstract: A wireless power transmission and communication network that provides efficient interrogation and powering of sensors for use on undersea vehicles. The present invention employs a wave-guide that allows the propagation of electromagnetic waves through a dielectric material that covers the exterior of an undersea vehicle's hull. Embedded within the dielectric material is an N dimensional array of Micro Electronic Mechanical Systems sensing devices coupled with radio frequency (RF) decoders and transceivers, and strips of conductive metal tape. Electromagnetic waves such as microwaves propagate through the dielectric material both powering the sensor network and addressing and interrogating individual sensing devices. The sensing devices take readings and then format and transmit the data results back across the wave-guide where they are received and processed by a digital processor within the hull of the undersea vehicle.

Abstract: A system and method are provided to supply power to and to communicate with an array of remote devices. The remote devices can be acoustic sensors or types of remote devices. In a preferred embodiment, the system includes a microwave source/signal demodulator that supplies wireless power and provides data interrogation signals to the sensors. The microwave transmission line is of a stripline construction. The source/demodulator radiates power to the sensor transceivers and receives data from the sensors. The source/demodulator can transmit sequential interrogation signals to activate address-selectable sensors. The source/demodulator may also decode received signals returning from the sensors. The stripline may be attached to a vessel's hull beneath a hull treatment layer and the sensors mounted on the surface of the hull treatment.

Abstract: An apparatus for enhancing the signal to noise ratio of piezoelectric hydhone outputs by decoupling the turbulent velocity pressure noise from the imbedded acoustic signal. An electromagnetic turbulent velocimeter is positioned coaxially with a piezoelectric hydrophone and flush mounted in a shell structure. The velocimeter senses the changes in the electric potential caused by the velocity of a conductive fluid passing through a magnetic field normal to the shell structure surface. The velocimeter responds to electromagnetic signals and is insensitive to acoustic signals. The piezoelectric hydrophone is positioned so as to contain the electromagnetic turbulent velocimeter magnetic field within the hydrophone field of view. The hydrophone responds to conductive fluid velocity pressure variations and is insensitive to electromagnetic signals. The output frequency components of the velocimeter are correlated or coupled with those of the hydrophone.

Abstract: A velocimeter, comprising a controlled magnetic field source and electric field sensors, the device being flush mounted in a vessel hull. The magnetic source comprises a drive coil which may be energized with either a DC current or an AC current at varous desired frequencies. The turns-area product and applied current are selected based on desired sensitivity. When the drive coil is energized, a uniform magnetic field is produced near the surface of, and normal to, the hull. The thickness of the uniform region is governed by the thickness of the boundary layer in the tubulent region. The magnetic field returns through the vessel hull structure in such a way that divB=0. Inside the coil, near the outboard external surface of the device, a pair of orthogonally disposed electric field sensors are located for measuring the electric field produced as a result of the interaction between the magnetic field and the conductive fluid.