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 autonomous hydrophone position locating and target tracking system employing a string or array of acoustic hydrophone equipped apparatuses that are easily and rapidly deployed over the ocean bottom within a preselected volume of water. For each bottom residing hydrophone, a dedicated cable provides surface location based on satellite generated GPS positioning data. Special real time cable deflection algorithms resident in the base unit electronic processor are continuously updated using the velocity gradient inputs from several in-line velocimeters positioned at different depths along the cable. The shape of the tether cable and the resulting position of the bottom unit mounted hydrophone is then back calculated in real time in three dimensions from the known global position of the surface buoy.

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 buoyant antenna for providing sufficient transmission time windows for munication at ultra-high and extremely-high frequencies. The antenna is configured to float on the surface of a body of water and is connected to a vessel through a communications cable. The buoyant antenna has a length and a stabile or rotation resistant cross-section which minimizes wash over when deployed in a manner which essentially eliminates in line tension on the antenna. The antenna is cylindrically shaped with sensor elements offset from the centerline. A high density mass is placed diametrically opposite the sensor elements and a high buoyancy foam fills out the remaining cylindrical shape. The high density mass creates a righting moment to maintain the sensor elements above the water line. The absence of in line tension during communication periods serves also to eliminate any detectable wake during those communication periods.

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.