Abstract: A replacement fin for an underwater vehicle includes a fin defining a socket that includes a bore of a first diameter and an internal spring recess of a larger diameter. A coil spring is retained in the spring recess and has coils of an elongated coil shape. The coil spring can occupy a first canted position in which the coils are canted in a direction generally into the bore and the coils can occupy a second canted position in which the coils are canted in a direction generally out of the bore. The UUV has a post that can include at least one circumferential recess configured to engage the coil spring, and which can function as a lock in some canted orientations of the spring. Alternately, the socket is defined in the UUV and the fin includes a post sized to be received in the socket.

Abstract: System and methods for generating super resolution images from geospatial images having any number of bands. A super resolution model, which uses deep convolution neural networks (DCNNs), is trained using individual image bands, a large crop size or tile size of 512×512 pixels, and a de-noise algorithm. Applying one or more algorithms to maintain the original color of the image bands improves the quality metrics of the super resolution images as measured by PSNR (peak signal-to-noise ratio) and SSIM (structural similarity index measure) of super resolution images. Further applying one or more algorithms to remove border effects introduced during the disclosed process reduces and/or eliminates seam lines between tiles and enhances the overall accuracy of the super resolution images.

Abstract: A system and method are disclosed for a precision variable-focus telescope that includes a telescope housing containing an optical system; a gap pad including a first side and a second side, wherein the first side of the gap pad is attached to the telescope housing; a heat spreader including a first side and a second side, wherein the heat spreader is contiguous with the telescope housing and wherein the second side of the heat spreader is attached to the second side of the gap pad; a temperature-sensing device connected to the first side of the heat spreader; and an electric-film heater including a first side and a second side, wherein the second side of the electric-film heater is attached to the first side of the heat spreader.

Abstract: A secure system includes a data port, a network on chip (NoC) module, a processor communicatively coupled to the NoC module, a communication interface operatively coupled to the processor and to the data port, an electronic field-programmable gate array (eFPGA) configuration module operatively coupled to the NoC module, and a clock operatively coupled to the NoC module. In a first modality, the communication interface is at least partially disabled. In a second modality, the communication interface is at least partially disabled, boundary scan operations are disabled, a RESET signal is held in a constant state, and/or redacted code is rendered inoperable. In a third modality, the communication interface is at least partially enabled to send and receive commands and data via the data port, the boundary scan operations are enabled, the RESET signal is not held in the constant state, and/or the redacted code is operable.

Abstract: A filter assembly of an optical system. The filter assembly may include a first spool, a second spool, and a film filter that operably engages with the first spool and the second spool and the film filter having at least two filters that are different from one another. The filter assembly may also include a drive assembly that operably engages with one of the first spool, the second spool, and the film filter for moving at least one filter of the at least two filters into optical alignment with a focal plane sensor of the optical system. The film filter of the filter assembly may also be made from a flexible material that bends when wound about the first spool and the second spool.

Abstract: Techniques are provided for guiding a projectile. A methodology implementing the techniques according to an embodiment includes generating a roll command based on a roll angle obtained from a steering map that causes a change in range and cross range of the projectile that results in a ground motion closest to a desired ground motion. The method also includes calculating a remaining maximum maneuver distance for the projectile, over a time period extending from the current time of flight to the end of flight. The calculation is based on integration a series of maximum maneuvers, obtained from the steering map, at time intervals within the time period. The method further includes generating a lift command for the projectile based on: distance between the target location and an impact point prediction (IPP) calculated at the current time of flight; an error estimate of the IPP; and the remaining maximum maneuver distance.

Abstract: Systems and methods for sorting signals. One example of a method includes receiving a plurality of data vectors representing a plurality of signals, establishing a sparse primary grid including at least one primary cell in which at least one data vector has been received, based on a first number of data vectors received within the primary cell exceeding a first threshold value, establishing a sparse secondary grid within the primary cell, the sparse secondary grid including at least one secondary cell in which one or more data vectors have been received, based on a second number of data vectors received within the at least one secondary cell exceeding a second threshold value, establishing a first smart object corresponding to the at least one secondary cell, and associating the one or more data vectors received within the at least one secondary cell with the first smart object.

Abstract: A particle accelerator random number generator system comprises a particle accelerator, a particle event detector, and a processing application. Operation steps include initiating the particle accelerator; detecting a particle event by the particle event detector; recording a binary event from the detected particle event; determining if sufficient binary events have been recorded for the desired random number strength; if not, return to the step of detecting a particle event; if so, converting the random number binary string to a random number generated hexadecimal; applying the random number generated hexadecimal string for an encryption key; and using the random number hexadecimal key to encrypt an application.

Abstract: Techniques are provided for a broadband microwave/millimeter-wave balanced-to-unbalanced transformer (balun). A balun implementing the techniques according to an embodiment includes a first impedance matching network configured to reduce insertion and return losses of a single-ended signal at a first port of the balun. The balun also includes a first planar bifilar coupled transmission line coupled to the first impedance matching network and configured to transform the single-ended signal into a differential signal. The balun further includes a second planar bifilar coupled transmission line coupled to the first bifilar coupled transmission line and configured to compensate for amplitude and phase imbalance induced on the differential signal by the first bifilar coupled transmission line.

Abstract: A dynamic controlling framework that is adapted to dynamically optimize existing routing decisions in an optimized link state routing (OLSR) platform to favor higher-bandwidth, lower-latency links in the active link database. The dynamic controlling framework includes a link probing tool that is in communication with OLSR platform where the link probing tool is adapted to dynamically measure estimated bandwidth, latency scores, or both estimated bandwidth and latency scores of active links in the active link database of the OLSR platform. The dynamic controlling framework includes a plug-in framework that is in communication with the OLSR platform and the link probing tool where the plugin framework is adapted to receive at least one link quality multiplier (LQM) metric computed by the link probing tool and to combine the at least one LQM metric with the OLSR platform's existing link quality (LQ) metric for enhancing route selection by the OLSR platform.

Abstract: An extensible open data framework asynchronously processes augments received in response to alterations in registered triggers. The framework includes an active data storage and an algorithm execution protocol. The active data storage includes short term data signals and long term data augments or emitter tracks. The execution protocol includes an execution thread pool having multiple threads that operate in parallel. The parallelization of the algorithm via the execution thread pool scales through multiple threads and cores to process data.

Abstract: An apparatus for converting frequency of signals includes a first switch having a first input terminal to receive a first input signal, a first output terminal, and a second output terminal, wherein the first switch couples the first input terminal to either the first or the second output terminal. A mixer circuit is coupled to the second output terminal, and is to mix the first input signal to a second input signal, to generate a modified input signal. A filter circuit includes a plurality of programmable filters, to receive the modified input signal and output a filtered signal. A second switch has (i) a second input terminal coupled to the first output terminal, (ii) a third input terminal to receive the filtered signal, and (iii) a third output terminal, wherein the second switch is to couple the third output terminal to either the second or third input terminal.

Abstract: A lightweight thermally dissipative EMI shield for electronics is composed of both metallic (e.g., conductive) and non-metallic (e.g., nonconductive) materials. The thermally dissipative EMI shield or cover may be formed of multiple layers of metallic or conductive materials and at least one layer of non-metallic or nonconductive material. There may be a conductive base layer, a lower intermediate nonconductive layer, an upper intermediate conductive layer, and an outer nonconductive layer. The conductive layers operate to thermally dissipate heat and suppress EMI, whereas the nonconductive layers provide lightweight rigidity and stiffness to support the EMI shield and protect components from foreign object ingress or damage of a circuit card or cover is coupled.

Abstract: A method of making GaP window slabs having largest dimensions of greater than 4 inches and GaAs IR window slabs having largest dimensions of greater than 8 inches, includes slicing and dicing at least one smaller GaAs or GaP single crystal boule, which can be a commercial boule, to form a plurality of rectangular slabs. The slabs are ground to have precisely perpendicular edges, which are polished to be ultra-flat and ultra-smooth, for example to a flatness of at least ?/10, and a roughness Ra of less than 10 nanometers. The slab edges are then aligned and fused via optical-contacting/bonding to create a large GaAs or GaP slab having negligible bond interface losses. A conductive, doped GaAs or GaP layer can be applied to the window for EMI shielding in a subsequent vacuum deposition step, followed by applying anti-reflection (AR) coatings to one or both of the slab faces.

Abstract: A method, system, and computer readable medium for performing a scalar agile parameter estimation for continuous-valued univariate parameters to estimate and track a likelihood of a measurement where a parameter distribution domain of an emitter is unknown, comprising: receiving a signal from an emitter source; measuring a feature of said signal; calculating a likelihood of said feature by a feature likelihood tracking model; adding a new parameter source model by creating a node, based on said feature likelihood; establishing a likelihood of a measurement using a measurement likelihood tracking model; starting a new feature track, based on said measurement likelihood; and assigning said feature to a track.

Abstract: A method of manufacturing a structurally competent, EMI-shielded IR window includes using a mathematical model that combines the Sotoodeh and Nag models to determine an optimal thickness and dopant concentration of a doped layer of GaAs or GaP. A slab of GaAs or GaP is prepared, and a doped layer of the same material having the optimal thickness and dopant concentration is applied thereto. In embodiments, the doped layer is applied by an HVPE method such as LP-HVPE, which can also provide enhanced GaAs transparency near 1 micron. The Drude model can be applied to assist in selecting an anti-reflective coating. If the model predicts that the requirements of an application cannot be met by a doped layer alone, a doped layer can be applied that exceeds the required IR transparency, and a metallic grid can be applied to improve the EMI shielding, thereby satisfying the requirements.

Abstract: GaAs IR window slabs having largest dimensions that are greater than 8 inches, and preferably greater than 12 inches, are grown using the Horizontal Gradient Freeze (HGF) method. Heat extraction is simplified by using a shallow horizontal boat that is only slightly deeper than the desired window thickness, thereby enabling growth of large slabs while also minimizing material waste and fabrication cost as compared to slicing and shaping thick plates from large, melt-grown boules. Single crystal seeds can be used to optimize the final orientation of the slabs and minimize secondary nucleation, thereby maximizing yield. A conductive doped GaAs layer can be applied to the IR window slab to provide EMI shielding. The temperature gradient during HGF can be between 1° C./cm and 3° C./cm, and the directional solidification can be at a rate of between 0.25 mm/h and 2.5 mm/h.

Abstract: IR window slabs of GaP greater than 4 inches diameter, and of GaAs greater than 8 inches diameter, are grown on a substrate using Hydride Vapor Phase Epitaxy (HVPE), preferably low pressure HVPE (LP-HVPE). Growth rates can be hundreds of microns per hour, comparable to vertical melt growth. GaAs IR windows produced by the disclosed method exhibit lower absorption than crystals grown from vertical melt near 1 micron, due to reduced impurities and reduced growth temperatures that limit the solubility of excess arsenic, and thereby reduce the “EL2” defects that cause high absorption near one micron in conventional GaAs boules. Silicon wafers can be used as HVPE substrates. For GaAs, layers of GaAsP that vary from 0% to 100% As can be applied to the substrate. EMI shielding can be applied by adding a dopant during the final stage of growth to provide a conductive GaAs or GaP layer.

Abstract: A method of growing large GaAs or GaP IR window slabs by HVPE, and in embodiments by LP-HVPE, includes obtaining a plurality of thin, single crystal, epitaxial-quality GaAs or GaP wafers, cleaving the wafers into tiles having ultra-flat, atomically smooth, substantially perpendicular edges, and then butting the tiles together to form an HVPE substrate larger than 4 inches for GaP, and larger than 8 inches or even 12 inches for GaAs. Subsequent HVPE growth causes the individual tiles to fuse by optical bonding into a large “tiled” single crystal wafer, while any defects nucleated at the tile boundaries are healed, causing the tiles to merge with themselves and with the slab with no physical boundaries, and no degradation in optical quality. A dopant such as Si can be added to the epitaxial gases during the final HVPE growth stage to produce EMI shielded GaAs windows.

Abstract: Techniques are provided for jammer detection. A methodology implementing the techniques according to an embodiment includes estimating an angle of arrival of a jamming signal, the jamming signal included in a received signal, and generating a direction finding (DF) confidence indicator associated with the estimated angle of arrival. The method also includes extracting the jamming signal from the received signal. The method further includes correlating the extracted jamming signal with previously extracted jamming signals to generate a correlation score and using the correlation score as a uniqueness assessment of the extracted jamming signal. The method further includes identifying characteristics of the extracted jamming signal and generating a characterization confidence indicator. The method further includes demoting the extracted jamming signal to non-jammer status based on one or more of the DF confidence indicator, the uniqueness assessment, and the characterization confidence indicator.