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McKnight D.S.,Integrity Applications Incorporated
Acta Astronautica | Year: 2016

Since the dawning of the space age space operators have been tallying spacecraft anomalies and failures then using these insights to improve the space systems and operations. As space systems improved and their lifetimes increased, the anomaly and failure modes have multiplied. Primary triggers for space anomalies and failures include design issues, space environmental effects, and satellite operations. Attempts to correlate anomalies to the orbital debris environment have started as early as the mid-1990's. Early attempts showed tens of anomalies correlated well to altitudes where the cataloged debris population was the highest. However, due to the complexity of tracing debris impacts to mission anomalies, these analyses were found to be insufficient to prove causation. After the fragmentation of the Chinese Feng-Yun satellite in 2007, it was hypothesized that the nontrackable fragments causing anomalies in LEO would have increased significantly from this event. As a result, debris-induced anomalies should have gone up measurably in the vicinity of this breakup. Again, the analysis provided some subtle evidence of debris-induced anomalies but it was not convincing. The continued difficulty in linking debris flux to satellite anomalies and failures prompted the creation of a series of spacecraft anomalies and failure workshops to investigate the identified shortfalls. These gatherings have produced insights into why this process is not straightforward. Summaries of these studies and workshops are presented and observations made about how to create solutions for anomaly attribution, especially as it relates to debris-induced spacecraft anomalies and failures. © 2015, Elsevier Ltd. All rights reserved. Source

Cook K.L.B.,Integrity Applications Incorporated
IEEE Aerospace and Electronic Systems Magazine | Year: 2010

The military satellite communications (MILSATCOM) infrastructure is typically broken into three categories: wideband, protected, and narrowband. Wideband systems emphasize high capacity, protected systems prioritize anti-jam features and covertness, and narrowband systems emphasize support to the disadvantaged user by providing low data rate communications to small / mobile users. This focuses on the existing wideband MILSATCOM infrastructure (namely the Defense Satellite Communications System and Global Broadcast Service), because the architecture that exists is aging technology that lacks the ability to provide the required bandwidth to the warfighters without relying on commercial satellites. Bandwidth is limited and expensive to purchase, resulting in the DoD leasing transponders on commercial communications satellites - a solution that may not always be an option. This also illustrates various technologies and future programs currently being investigated by the Department of Defense (DoD) in order to augment and/or replace existing systems, and the resulting capability and benefits provided to the warfighter. These programs include the Wideband Global SATCOM (WGS) (previously known as Wideband Gapflller Satellite System), and the Advanced Wideband System (AWS) / Transformational Satellite Communications System (TSAT). Both WGS and AWSITSAT will significantly increase the bandwidth capacity of the wideband MILSATCOM architecture. These military initiatives take advantage of nascent technology such as IP router technology and laser cross-links to maximize performance. Finally, thia describes several techniques to augment these MILSATCOM programs and increase their capacity and effectiveness, including: use of a network-style approach (vice point-to-point), combining space and terrestrial systems, use of near-space communication platforms (e.g., high-altitude. UAVs or balloons), operating at higher frequencies, use of multiple satellites and re-use frequencies, and use of IP accelerators. These techniques increase the bandwidth capacity and improve its effectiveness by providing diversity, better quality of service via multiple relays, improved link performance via network architecture, and increase the amount of effective bandwidth available by including airborne platforms as additional communications relays. © 2010 IEEE. Source

Kreucher C.,Integrity Applications Incorporated
IEEE Antennas and Propagation Magazine | Year: 2011

This paper describes a statistical signal-processing method for exploiting narrowband bistatic RF measurements to detect and track moving people (hereafter referred to as "dismounts"). In our approach, RF measurements are made by a constellation of narrowband radar units, arranged around a surveillance region. There are several benefits of narrowband radar in this application, which we describe in the paper. However, the narrow bandwidth means that individual measurements only yield coarse information about target state. We show that by fusing measurements from multiple bistatic sensors over time with a Bayesian nonlinear-filtering algorithm, we can effectively estimate dismount position and velocity using as little as 5-10 m bistatic range resolution. We illustrate the algorithm's efficacy with an experiment where a moving person is detected and tracked from a constellation of four narrowband bistatic sensors. Source

Integrity Applications Incorporated | Date: 2011-01-24

In some embodiments, the present invention relates to methods or suppressing edge ringing in images. For example, in some embodiments a method of processing an image to suppress ringing and broadened edges induced by image correction processing, includes high-pass filtering a first image to obtain a second image, processing said second image including applying non-linear apodization to said second image to obtain a third image, low-pass filtering said first image to obtain a fourth image, and combining the third image and the fourth image to obtain an output image, wherein the output image is characterized by having reduced edge-response sidelobes as compared to the first images. In some embodiments, the present invention relates to devices comprising means and/or modules to suppress edge ringing in images.

Agency: Department of Defense | Branch: Air Force | Program: SBIR | Phase: Phase II | Award Amount: 742.03K | Year: 2010

This proposal focuses on developing innovative algorithms which exploit a constellation of narrowband RF sensors to detect IED placement activities. The algorithms include techniques for (i) detecting, localizing, and analyzing behavior of vehicles, (ii) imaging to determine if an area has been disturbed, and (iii) optimally locating sensors to enable items (i) and (ii). In Phase I, we developed a suite of baseline algorithms. These included an new nonlinear filtering approach to detection and localization and a novel CRB method of optimal sensor placement. The algorithms were illustrated in simulations involving both sensor placement and target tracking. In Phase II, we propose to refine and extend the algorithms from Phase I, develop additional algorithms, and evaluate the system on real data. Refinements include improved modeling and characterization of urban phenomena and modeling enhancements. Additional algorithms include development of kinematic profiling and compressed sensing coherent change detection. Real data will be used to validate the algorithms. The success of the Phase I algorithms warrants continued R&D in Phase II. The expected result of the Phase II effort is a software prototype for automated selection of sensor placement, detection and tracking of vehicles, kinematic profiling, and CCD imaging. BENEFIT: At the completion of this effort, the proposed technologies will provide an algorithm suite for automatic target detection, kinematic classification, high-resolution imaging, and tracking. These algorithms apply in many commercial applications, including border protection, airport security, and even traffic analysis. In particular, DHS, the FAA, and other agencies routinely need to secure a border or perimeter and analyze all traffic passing through. Furthermore, policing applications often require certain hot-spots to be intensely monitored, particularly in situations poorly equipped for traditional EO techniques (e.g., nighttime and poor weather conditions). IAI and MTRI have engaged AKELA, a leading manufacturer of RF hardware both for commercial and military applications, as a potential vendor for the first product from this technology. No funding for AKELA is costed into the Phase II effort. However, discussions and meetings for transition planning are included. The first product would incorporate the algorithms developed here and narrowband hardware for an intrusion monitoring system that could be sold to police departments, the FAA, and commercial entities requiring perimeter control.

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