Abstract: A method and system to rapidly, passively, range and track maneuvering airborne emitters (enemy targets and threats) for tactical fighters using batch based recursive estimators for track initialization and track maintenance that includes providing information processing that has angle and signal amplitude data, threat database, and feedback from pilot cue analysis. The system includes pilot cue analysis which computes airborne emitter (target and threat) heading and corresponding accuracy to determine if sufficient accuracy is available to present the pilot with proper pilot cue options. The first stage is a range bank also called a compound parallel hypothesis evaluator and the second stage is an interactive multi-model. Both stages provide for the output of the algorithm to be a range measurement and an associated confidence factor. The algorithm inputs azimuth angle elevation angle and range and is capable of inputting data from three different data pre-processors (i.e., sensor data fusion).

Abstract: An algorithmic approaches that can be implemented in software/firmware/hardware that filters out stable PRI patterns detected within a system that is prosecuting against radar based transmissions are disclosed. The algorithms allow downstream computing assets to concentrate their limited resources on the more complex emitter PRI pattern types. Thus, a portion (e.g., stable signals) of the pulse deinterleave and PRI identification problem is solved without requiring the more computationally expensive processing. The disclosed algorithms can be employed, for example, in electronic support measures (ESM) systems, electronic intelligence (ELINT) systems, and/or a electronic countermeasures (ECM) systems. The algorithms employ linear detection, linear regression, or a combination of linear detection and linear regression, thereby providing a “dual voting” scheme that decreases the occurrence of false positives.

Abstract: Techniques for determining the angles of arrival of multiple simultaneous cochannel sources using only a single RF receiver sampling and downconversion channel is disclosed. This is accomplished by sequentially forming several known mixtures of multiple antenna signals in the RF domain prior to downconversion and digitization. Angle of arrival information is then recovered through the application of higher order statistics and subspace fitting techniques. The same principles can be applied to other P-element receiver arrays (e.g., acoustical receiver array).

Abstract: Techniques for reading data from a storage medium (150) having a high track density prone to adjacent track interference are disclosed. One or more sensing elements (120) are used to extract data stored on adjacent tracks. Multiuser detection (130) is then used to detect/decode a single track that is closely spaced to its neighboring tracks, resolve interference from adjacent tracks, or to simultaneously detect/decode multiple adjacent closely packed tracks.

Abstract: A Tonpilz transducer which includes a first stack of piezoceramic elements with a first plurality of electrodes connected to form a first pair of external connections. There is also a second stack of piezoceramic elements with a second plurality of electrodes connected to form a second pair of external connections, and the first and second stacks of piezoceramic elements have opposed polarizations.

Abstract: An integrated photonic device having a vertical optical connection between vertically oriented waveguides and a process for making the same is disclosed. A first waveguide is patterned and etched onto an underlying substrate. A cladding layer is placed over the waveguide and substrate. The cladding layer is coated with a photoresist, and then patterned with holes that are slightly offset from the underlying waveguide. The holes are implanted with nitrogen doses at an angle. The nitrogen doses form an angled implantation of SiON. The material change and accompanying index of refraction change due to the angled implantation optically couples the underlying waveguide with an outside surface of the cladding layer. A second waveguide or circuit can then be patterned on the outer surface of the cladding and connected to the angled implantation and underlying waveguide. Multiple layers of waveguides or circuitry can be connected to each other in this manner.

Abstract: An inexpensive, small, low-power consumption, wide-band, high resolution spectrum analyzer is provided as a listening device for throw-away applications such as surveillance that involve deployment of large numbers of battery-powered spectrum analyzer modules to detect a signal source such as two-way radio traffic. Power requirements are minimized by the utilization of only one chirp generator to elongate battery life while providing a high resolution result. In order to minimize power drain the spectrum analyzer includes a single compound-chirp Fourier Transform generator. The compound chirp generator is used in one embodiment with a surface acoustic wave, SAW, dispersive delay line in conjunction with a surface electromagnetic wave, SEW dispensive delay line.

Abstract: A technique is disclosed for calculating the phase and amplitude weighting factors for use with a specific compact antenna range that synthesize an in phase, constant amplitude planar wave front that appears to have been transmitted from the far field. The weighting factors are used to weight RF signals after they are received by a full size or scaled radio direction finding array mounted on a platform during testing of the antenna array on the compact antenna range. The weighted received signals accurately replicate the antenna array response in the far field, including electromagnetic glint caused by the platform on which the antennas are mounted, and are stored in complex voltage form as a calibration table for the array.

Abstract: Dual-array two-port GPS antenna systems can provide horizon to zenith reception for differential GPS applications. On a single mast, an antenna system may include a lower array of sub-arrays (e.g., fifteen sub-arrays) to provide elevation coverage from horizon up to about 55 degrees elevation and an upper array of sub-arrays (e.g., three sub-arrays) to provide elevation angle coverage from zenith down to about 55 degrees elevation. Each sub-array may be of the same construction including four dipoles positioned at different azimuth locations and configured to provide a progressive-phase-omnidirectional (PPO) azimuth pattern suitable for reception of circularly polarized signals. In a particular embodiment the three sub-arrays of the upper array have PPO azimuth patterns with differing azimuth alignments and differing excitation values to provide a desired elevation angle coverage characteristic.

Abstract: A low radar cross-section monocone antenna is provided with an ultra-wide bandwidth in the microwave region of the electromagnetic spectrum running from 1 gigahertz to 18 gigahertz by decreasing the low frequency cutoff through enlarging the overall dimensions of the cone while at the same time maintaining the base diameter of the apex of the cone to the initially-set dimension that establishes the high frequency cutoff of the antenna. The apex of this cone that serves as its feed point has a base diameter that results in the wide bandwidth, with the monocone antenna having a 5 dBi gain and omnidirectional coverage.

Abstract: A compact fixturing means is disclosed that delivers two or more phase tracked channels of high power (e.g., 1000 Watts) to an antenna that can produce a multiplicity of polarization depending on the phase relationship of the delivered signals. Coaxial cables are used as a service loop to provide two or more channels of phase tracking and high power signals to the multi-polarized antenna. A flat spiral spring is configured within the fixture to the guide two (or more) coaxial cables along a spiral loop to allow approximately equal tension on the cables as the fixture is rotated. The flat spiral spring is operatively coupled to a rotation plate and progresses form an inner radius proximate the fixture input to an outer radius proximate the fixture output.

Abstract: A computationally efficient modeling system for imagery scales both the original image and corresponding principal component tiles in the same proportion to be able to extract scaled principal components. The system includes recovery of feature weights for the image model by extracting the weights from the reduced size principal component tiles. The use of the reduced size tiles to derive weights dramatically reduces computer overhead both in the generation of the files and in the generation of the weights, and is made possible by the fact that the weights from the scaled down tiles are nearly equal to the weights of the tiles associated with the full size image. The subject system thus reduces computation and the number of bits required to represent features by first scaling the image and then tiling the image in the same proportion. In one embodiment, the scaled down tiles are used as training exemplars used to generate the principal components.

Abstract: Techniques for switching an optical element from one path to another, where each path has high dimensional stability in a harsh thermal and dynamic environment, are disclosed. In one particular embodiment, the optic is mounted on a rotable platform. A spring mechanism preloads the platform against a hard stop, thereby providing accurate and repeatable placement of the optic in its deployed position. The motor's actuator arm is the only element whose position is sensed, allowing the switching system to work without requiring highly precise position feedback. In the stowed position, the spring mechanism operates as a firm tension cable, thereby securing the optic out of the laser beam path.

Abstract: A miniature broadband monopole antenna design configured with integrated band-selecting filtering is disclosed. The antenna is electrically folded, and includes top and bottom monopole sections, with a meanderline to provide an inductive load between the two sections. The overall antenna structure can be embedded in a relatively small, RF transparent, composite structure (e.g., such as the fin of a guided munition), and has minimal impact on aerodynamics (low drag). The top, bottom, and meanderline elements of the antenna operate together to collectively provide multi-band operation (e.g., 30 MHz to 3 GHz).

Abstract: A system is provided for use with a multi-user detector MUD, which dramatically decreases the processing time for separating out interfering transmissions from a number of users by eliminating from each processing iteration consideration of those bit estimates for which the probability or estimate of their value exceeds a predetermined threshold and can therefore be declared “certain”. In a Turbo MUD environment in which the output of the MUD is coupled back to the MUD through an error correction system, the output of the error correction is thresholded such that those bit estimates having probabilities or estimates greater than a predetermined threshold are assigned a quantized value and are eliminated from further processing by the MUD. For certain low-complexity processing Turbo MUDs there can be as much of a reduction as one-third in processing time, whereas for full MUD processing, the reduction in processing time can be as much as 1/30th.

Abstract: A system is provided for rapidly prototyping monolithic microwave integrated circuit modules to provide an experimental structure that can be physically made to operate by stereolithographically rendering an SLA part directly from the designer's drawings and by coating the part with a conductive layer, with the smoothness being better than 0.001 inch and with the dimensional accuracy being better than 3 mils for some applications. In one embodiment, the coating for the SLA model is made from either rhodium or gold having a thickness of less than 1/10,000th of an inch, with a nickel barrier being first deposited followed by the gold. The particular SLA plastic is a high temperature plastic to prevent bubbling during the metal deposition step which in one embodiment involves sputtering. The coated model has a microfinish of Ra<0.001 inch, with active devices being electrically attached to the coating through the use of conductive adhesives or eutectic solder.

Abstract: An RF tag is provided to communicate with an interrogating source in which the tag has programmability and flexibility to uplink data to multiple platforms. As such the RF tag functions as a miniature programmable transceiver capable of communicating with a plurality of different platforms each having different waveform characteristics. With well-controlled spectral characteristics due to stored waveforms and the use of specialized direct digital up and down conversion techniques, data rates up to 256 kbps are achievable. The tag is thus capable of converting microwave signals directly to digital inputs, and the transmitter generates microwave signals directly from digital outputs. Flexible digital processing also allows a throughput of 900 BOPS when using field programmable gate arrays.

Abstract: An active armor system, which includes a first armor layer and a second armor layer. An interior space is interposed between the first and second armor layer. A third layer is also positioned preferably adjacent to and on the inner side of the first layer. This third layer is comprised of a material selected from a piezoelectric material, and electrostrictive material, and a magnetostrictive material. The third layer may also be characterized as any material capable of producing an electrical or magnetic field within the space in response to the application of mechanical force on this third layer. The application of force on the third layer as a result of the impacting of a shaped charge projectile on the first armor layer will result in the production of an electric or magnetic charge in the interior space which will disrupt the formation of the shaped charge gas jet so as to prevent the penetration of the second armor layer.

Abstract: A Fermi threshold voltage FET has Germanium implanted to form a shallow abrupt transition between the semiconductor substrate dopant type, or well dopant type, and a counter doping layer of opposite type closely adjacent the surface of the semiconductor substrate. Germanium is a charge neutral impurity in silicon that significantly reduces the diffusion motion of other impurity dopants, such as As, P, In, and B in the regions of silicon where Ge resides in significant quantities (i.e. greater than 1E19 cm sup3).

Abstract: A trusted computer system that offers Linux® compatibility and supports contemporary hardware speeds. It is designed to require no porting of common applications which run on Linux, to be easy to develop for, and to allow the use of a wide variety of modern development tools. The system is further designed to meet or exceed the Common Criteria EAL-5 or higher rating through incorporation of required security features, as well as a very high level of assurance for handling data at a wide range of sensitivity (e.g., classification) levels in a wide range of operational environments. This is achieved through the implementation of a well-layered operating system which has been designed from the ground up to enforce security, but which also supports Linux operating system functions and methods.