Abstract: An advance warning system including an antenna pair and an RWR system to receive first, second and third signals for computing a frequency for all the signals and a phase difference between the signals. If the frequencies are within a threshold frequency difference and the phase difference is less than a threshold phase difference, two signals can be associated. If the frequencies are not within the threshold frequency difference, the RWR system generates a set of ambiguous angle of arrival AoA for the signals and correlates the two sets of ambiguous AoA to determine if there is a common AoA. If there is a common AoA, a third set of ambiguous angle of arrival AoA for a third signal is generated to determine if the three sets correlate. If there is a common AoA for all three signals, the three signals are associated.

Abstract: An advance warning system including an antenna pair and an RWR system to receive first, second and third signals for computing a frequency for all the signals and a phase difference between the signals. If the frequencies are within a threshold frequency difference and the phase difference is less than a threshold phase difference, two signals can be associated. If the frequencies are not within the threshold frequency difference, the RWR system generates a set of ambiguous angle of arrival AoA for the signals and correlates the two sets of ambiguous AoA to determine if there is a common AoA. If there is a common AoA, a third set of ambiguous angle of arrival AoA for a third signal is generated to determine if the three sets correlate. If there is a common AoA for all three signals, the three signals are associated.

Abstract: A geolocation system on a platform, for example, an airplane, to identify a location of a signal emitting site includes an inertial navigation system and an array of signal detectors. A first subset of the detectors is on a flexing portion of the platform and a second subset of detectors is on a rigid portion of the platform. An inertial measurement unit is disposed adjacent to each of the detectors on the flexing portion. A locator module is configured to: calculate a respective velocity and a respective position of each one of the detectors positioned on the flexing portion as a function of respective inertial measurement data; and determine a position of the emitter as a function of the calculated velocity, calculated position, inertial navigation data, the detected signal data and data defining a flexure relationship between the flexing and rigid portions of the platform.

Abstract: A system for multi-ship geolocation of a signal emitter of interest uses differential GPS (DGPS) to determine the relative positions of two or more receivers in order to determine baseline vectors between them. The geolocation of the signal emitter is then determined as a function of the baseline vectors. The use of DGPS allows for more efficient and useful geometries between the receivers as two receivers can both be in a mainlobe of an emitted signal and still provide increased geolocation accuracy.

Abstract: A geolocation system on a platform, for example, an airplane, to identify a location of a signal emitting site includes an inertial navigation system and an array of signal detectors. A first subset of the detectors is on a flexing portion of the platform and a second subset of detectors is on a rigid portion of the platform. An inertial measurement unit is disposed adjacent to each of the detectors on the flexing portion. A locator module is configured to: calculate a respective velocity and a respective position of each one of the detectors positioned on the flexing portion as a function of respective inertial measurement data; and determine a position of the emitter as a function of the calculated velocity, calculated position, inertial navigation data, the detected signal data and data defining a flexure relationship between the flexing and rigid portions of the platform.

Abstract: A more dynamic situational awareness may be provided by processing received attack radar pulses in a radar warning receiver in such a way as to provide an indication of where the aircraft is within the transmit beamwidth of the attack radar.

Abstract: A more dynamic situational awareness may be provided by processing received attack radar pulses in a radar warning receiver in such a way as to provide an indication of where the aircraft is within the transmit beamwidth of the attack radar.

Abstract: A system and method for mapping a ground strip having an extended range swath includes a synthetic aperture radar (SAR) mounted on a moving platform. The ground strip is divided into columns that extend from the near-range edge of the ground strip. Each column contains two or more portions and has an azimuthal length equal to the radar's near-range beamwidth, W. Each column is sequentially illuminated while the platform moves through a distance, Lillum, (equal to the near range beamwidth). During column illumination, portions within the column are sequentially mapped by altering the depression angle, &phgr;, of the radar beam. Each portion is SAR mapped using a respective SAR aperture length with the sum of aperture lengths for the column being less than or equal to the distance the platform moves during illumination. The resultant maps are mosaicked together to produce one contiguous SAR map of the ground strip.

Abstract: A cellular radar system is disclosed for detecting and tracking objects in a surveillance area that is divided into cells. Each cell is scanned by at least two radars to produce two (or more) respective datastreams for the cell. Orbiting unmanned air vehicles can be used as radar platforms. The resulting datastreams for each cell are then multilaterated by a processor to produce a multilaterated datastream for each cell. The multilaterated datastreams for all cells are then combined by the processor and the resulting data used to detect or track one or more objects in the surveillance area. The fused multilaterated datastreams allow objects to be tracked as they move from cell to cell.

Abstract: The occurrence of internally-formed contaminants or negatively-charged particulates within a plasma is minimized by preventing such from becoming trapped in the plasma. The plasma is formed in a plasma chamber having control electrodes and reference electrodes. The control electrodes are biased with a negative potential. The plasma assumes a potential more positive than the control electrodes. The reference electrodes are then biased to be more positive than the plasma. Hence, negative ions or negatively-charged particulates in the plasma are attracted to the more positive reference electrodes, and thus escape the plasma without being trapped therein, and are not available to serve as nucleation or agglomeration points for contaminants. A pair of Helmholtz coils produce a magnetic field having magnetic field lines that run longitudinally between the control electrodes.

Abstract: Improved methods and techniques for fabricating a panel of control cells, or a “control panel”, useful in various electromagnetic turbulence control (EMTC) applications includes a layered structure which includes three main components or layers: a metal substrate or backing plate having a high magnetic permeability; a ribbed magnetic structure attached to the metal substrate; and an electrode board bonded to the ribs of the magnetic structure. The ribbed magnetic structure is realized, in one embodiment, by a series of rare earth permanent magnets placed side-by-side using a bowed tool to create permanent magnet columns. The magnet columns thus formed are precisely positioned and glued to the substrate or backing plate so as to form parallel magnetic ribs. An electrode board, similar to a printed circuit board, is then bonded to the ribs of the magnet columns, e.g., so that a back side of such electrode board rests on top of the magnetic columns or ribs.

Abstract: Magnetic and electric fields are used in a controlled manner to create Lorentz forces that affect the flow of a conductive fluid near the boundary layer of a control tile, or a matrix of control tiles, immersed in a conductive fluid. The control tiles are combined to form control cells, with each control cell including a pair of electrodes and at least one permanent magnet. The pair of electrodes are coupled to a current source which biases the electrodes to cause an electrical current to flow from a positive electrode (anode), through the conductive fluid in which the cell electrodes are immersed, to a negative electrode (cathode). The current source is time multiplexed to better control the direction of the current flow between adjacent electrodes. The permanent magnet(s) generates a magnetic field which interacts with the electrical current to create a Lorentz force that influences the flow of the conductive fluid, near the boundary of the control tile, e.g.

Abstract: Magnetic and electric fields are used in a controlled manner to create equal and oppositely-directed Lorentz forces tangential to the surface of a control tile that affect the flow of a conductive fluid near the boundary layer of the control tile, or a matrix of control tiles, immersed in a conductive fluid. The control tiles are combined to form control cells, with each control cell including a pair of electrodes and at least one permanent magnet. The pair of electrodes are coupled to a current source which biases the electrodes to cause an electrical current to flow from a positive electrode (anode), through the conductive fluid in which the cell electrodes are immersed, to a negative electrode (cathode). The current source may be time multiplexed to better control the direction of the current flow between adjacent electrodes.

Abstract: A long plasma formation tube is imbedded in a high magnetic field, with magnetic field lines passing axially through the tube, and with the tube being placed proximate or inside of a resonant cavity. Electromagnetic energy resonates in the resonant cavity representing stored microwave energy. The power density of the stored microwave energy is a function of the cross-sectional area of the resonant cavity. A portion of the stored microwave energy is concentrated to increase its power density, and coupled into the plasma formation tube, which tube has a smaller cross-sectional area than the resonant cavity. The coupled energy excites a whistler wave in the plasma formation tube that forms the plasma within the tube. In one embodiment, the stored microwave power is concentrated by funneling it through a metallic iris that forms one end of the resonant cavity, with a tip of the plasma formation tube being positioned near the metallic iris.

Abstract: A gas discharge laser includes a cylindrical symmetric discharge tube, having a prescribed gas therein at a low pressure, centered within a microwave-resonant cavity immersed in an axial magnetic field. Appropriate mirrors, optically aligned with a longitudinal axis of the discharge tube, are positioned at each end of the plasma column, one of which is partially transmissive. A pair of Brewster windows, or a pair of flat windows with antireflective coatings, one at each end of the discharge tube, are interposed between the mirror and discharge tube. Electromagnetic energy in the microwave range, e.g., greater than 1 GHz, is injected into the cavity and made to resonate in an appropriate mode. A large portion of the resonating energy is coupled into the discharge tube, causing a plasma to be created and maintained. The axial magnetic field confines the plasma to the center regions of the discharge tube, away from the walls, so as to form a plasma column.