Abstract: A buoyant cable antenna system includes an HF antenna section connected to an outboard end of a VLF/LF antenna. With respect to the HF antenna, the VLF/LF appears to be a standard coaxial cable so that the HF antenna can be configured as desired for HF antenna operation. The VLF/LF antenna is comprised of a segment of coaxial cable. The inboard end of the braided outer conductor of the segment of coaxial cable is connected to ground through a capacitor so that the VLF/LF signals are effectively isolated from ground. In this way, VLF/LF currents are induced on the outer braided conductor of the segment of coaxial cable to thereby operate as the VLF/LF antenna.

Abstract: The present invention is a submarine mast antenna controller for controlling a plurality of functions performed by an antenna mast of a submarine. The submarine mast antenna controller is a solid state electronic control unit on a single card that monitors various submarine mast antenna system sensors and motors, and controls electromechanical devices associated with the sensors and improves functionality over the former ACU system by consolidating control interfaces and indicators in one computer terminal via a VXI interface.

Abstract: A buoyant cable antenna system includes an HF antenna section connected to an outboard end of a VLF/LF antenna. With respect to the HF antenna, the VLF/LF appears to be a standard coaxial cable so that the HF antenna can be configured as desired for HF antenna operation. The VLF/LF antenna is comprised of a segment of coaxial cable. The inboard end of the braided outer conductor of the segment of coaxial cable is connected to ground through a capacitor so that the VLF/LF signals are effectively isolated from ground. In this way, VLF/LF currents are induced on the outer braided conductor of the segment of coaxial cable to thereby operate as the VLF/LF antenna.

Abstract: The invention as disclosed is of a buoyant cable antenna for use with underwater vehicles having improved bandwidth through the use of discrete distributed loading along the antenna. The buoyant cable antenna is designed with an antenna wire that is divided into N equal length segments of length d/2. A capacitor is coupled between every other segment such that capacitors are separated by a distance d. A shunt inductor is coupled to the antenna wire between the adjoining segments not separated by a capacitor such that the shunt inductors are separated by a distance d. This antenna design provides a substantially improved impedance bandwidth over existing prior art antennas at high frequency without increasing the physical profile of the antenna and without the use of active circuit elements.

Abstract: The invention as disclosed is of a buoyant cable antenna for use with underwater vehicles having improved bandwidth through the use of discrete distributed loading along the antenna. The buoyant cable antenna is designed with an antenna wire that is divided into N equal length segments of length d/2. A capacitor is coupled between every other segment such that capacitors are separated by a distance d. A shunt inductor is coupled to the antenna wire between the adjoining segments not separated by a capacitor such that the shunt inductors are separated by a distance d. This antenna design provides a substantially improved impedance bandwidth over existing prior art antennas at high frequency without increasing the physical profile of the antenna and without the use of active circuit elements.

Abstract: Means and methods of remotely powering a plurality of sensor coils are described. The plurality of sensor coils can be inductively coupled to a single, primary coil so as to bias the active circuitry of the sensors. The primary and sensor coils can have a separation on the order of inches, such that the sensors can be mounted exterior to a vessel and the primary coil can be mounted interior to the vessel. In some embodiments, the primary coil can be a wire coil. In other embodiments, the primary coil can be a planar coil pattern etched onto a printed circuit board.

Abstract: Means and methods of remotely powering a plurality of sensor coils are described. The plurality of sensor coils can be inductively coupled to a single, primary coil so as to bias the active circuitry of the sensors. The primary and sensor coils can have a separation on the order of inches, such that the sensors can be mounted exterior to a vessel and the primary coil can be mounted interior to the vessel. In some embodiments, the primary coil can be a wire coil. In other embodiments, the primary coil can be a planar coil pattern etched onto a printed circuit board.

Abstract: A buoyant cable antenna element is taught that employs a specific double-negative meta-material sheath with a negative permeability. The double-negative meta-material sheath is disposed over the insulated wire portion of the buoyant cable antenna element. The double-negative meta-material sheath enables a deliberate reduction in the antenna wire inductance to a zero value at a desired critical frequency. Reducing the antenna wire inductance to zero creates a traveling wave structure antenna having enhanced bandwidth.

Abstract: The present invention by propagates a traveling wave of electric current along a microstrip antenna structure rather than a standing wave. By loading an antenna with a series of capacitive gaps of the correct values, the shape of the electric current distribution can be tailored to suppress the resonant properties of the antenna, specifically the standing wave of electric current that normally forms along the antenna structure. A microstrip antenna having a “bulls-eye target” structure comprised of a center disk and concentrically larger capacitively coupled annular sections will tailor the shape of the electric current distribution to achieve a suppression of the resonant properties of the antenna, thereby increasing the antenna bandwidth.

Abstract: A dielectric constant waveguide measuring apparatus preferably comprises a rectangular waveguide aperture on each end with a width a and height b. The waveguide frame is preferably split to permit the waveguide to be opened for insertion of the unknown material into a middle reduced cross-sectional area portion of the waveguide frame. In one embodiment, a metal septum is inserted between two samples of the unknown material to thereby reduce the cross-sectional area of the waveguide aperture by splitting width a of the rectangular waveguide in half. The waveguide frame is closed and a frequency response of the waveguide is then measured. The dynamic dielectric constant of the unknown material is determined from the frequency of the lowest order minimum value of the frequency response of the waveguide apparatus wherein the unknown material has been inserted.

Abstract: This invention serves as a method and apparatus for delivering power to a series of remote sensors in an on hull sensor grid for the purpose of biasing the active circuitry on the sensors. It requires no physical connection between the source of power and the sensor. It works by delivering electrical energy across the insulating gap that separates the sensor from the hull by means of a displacement current. In particular, the method and device include a conducting layer interposed between inner and outer decouplers and a ground plane interposed between a bonding layer and the inner decoupler. An application of alternating current to the ground plane will activate the conducting layer and provide power to the sensors at a location of the outer decoupler. The inner decoupler acts as a capacitor and the ground plane further provides an electrical path back to the hull.

Abstract: A relative phase shift is induced in the signals of a pair of identical orthogonal antennas such that when the signals are combined the signals are 90 degrees out of phase. This is done in order to eliminate the null along the axis between the two dipole moments of the antennas such that the system has equally good reception from all azimuth angles over a broad range of frequencies. The phase shift is accomplished with the use of single pole operational amplifier circuits whose pole frequencies are adjusted by means of a potentiometer prior to implementation of the antenna system.

Abstract: A segmented patch antenna has a dielectric material substrate, a plurality of primary electrically conductive segments consecutively disposed on the dielectric material substrate and spaced apart so that a portion of the substrate is exposed between any pair of adjacent primary segments, and a layer of dielectric material disposed over the primary segments. Secondary electrically conductive segments are disposed over the layer of dielectric material wherein each secondary segment corresponds to a pair of adjacent primary segments. Each secondary segment overlaps a portion of each primary segment of the corresponding pair of adjacent primary segments to which that secondary segments corresponds. The overlap of each secondary segment with a portion of each primary segment in a pair of adjacent primary segments produces a plurality of capacitive gaps that capacitively couple the primary and secondary segments together to define a single antenna.

Abstract: A microstrip patch antenna with progressive slot loading is provided. A rectangular patch of electrically conductive material has a plurality of slots formed therein with each slot having its center aligned with the centerline of the patch's long dimension. Each slot further has its longitudinal axis perpendicular to the centerline. The slots are arranged in an order starting at a position n=1 that is furthest from the patch's feedpoint so that, for an n-th slot, the inequalities Ln>Ln+1 and Wn<Wn+1 are always satisfied. In general, the length decreases linearly with each successive slot while the width increases exponentially with each successive slot.

Abstract: A digital goniometer and steering method are provided which may be used, in a preferred embodiment, for producing a figure-eight antenna reception pattern oriented at any selectable angle. The digital goniometer works with the signals from a pair of orthogonal antenna loops. In a presently preferred embodiment a first register and a second register are provided for a respective first variable gain amplifier and a second variable gain amplifier. The first and second registers receive from software a digital value related to a sine function and cosine function of the selectable angle. The first and second registers are utilized to set the gain of the first and second variable gain amplifiers. The outputs of the first and second variable gain amplifiers are added to produce the reception signal.