Recent Publications, Papers, and Patents by the Technical Staff
First published May 2013, Crosslink® magazine
J. Barrie, P. D. Fuqua, K. A. Folgner, and C. T. Chu, “Control of Stress in Protected Silver Mirrors Prepared by Plasma Beam Sputtering,” Applied Optics, Vol. 50, No. 9, pp. C135–C140 (2011).
D. Bearden, M. Cowdin, and J. Yoshida, “Evolution of Complexity and Cost for Planetary Missions Throughout the Development Lifecycle,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
P. M. Belden, T. S. Rose, S. M. Beck, et al., “Narrowband Er:YAG Nonplanar Ring Oscillator at 1645 nm,” Optics Letters, Vol. 36, No. 7, pp. 1197–1199 (2011).
R. L. Bishop, A. B. Christensen, J. H. Hecht, et al., “Evaluation of Ionospheric Densities Using Coincident OII 83.4 nm Airglow and the Millstone Hill Radar,” Journal of Geophysical Research, Vol. 117, No. A5, pp. A05331.1–A05331.8 (2012).
R. L. Bishop, J. H. Hecht, A. B. Christensen, et al., “Measurement and Application of the O II 61.7 nm Dayglow,” Journal of Geophysical Research, Vol. 117, No. A1 (2012).
R. E. Bitten and E. M. Mahr, “Instrument Schedule Delays: Potential Impact on Mission Development Cost for Recent NASA Projects,” Geoscience and Remote Sensing Symposium (IGARSS), 2012 IEEE Aerospace Conference, pp. 5658–5661 (Big Sky, MT, 2012).
R. Bitten, E. Mahr, et al., “Instrument First, Spacecraft Second (IFSS): Options for Implementing a New Paradigm,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
A. Z. Brethorst, N. Desai, D. P. Enright, et al., “Performance Evaluation of Canny Edge Detection on a Tiled Multicore Architecture,” Parallel Processing for Imaging Applications (San Francisco, CA, 2011).
A. Bushmaker et al., “The Influence of Substrate in Determining the Band Gap of Metallic Carbon Nanotubes,” Nano Letters, Vol. 12, No. 9, pp. 4843–4847 (2012).
A. Bushmaker, S. La Lumondiere, et al., “Electrical and Optical Characterization of Surface Passivation in GaAs Nanowires,” Nano Letters, Vol. 12, No. 9, pp. 4484–4489 (2012).
J. C. Camparo et al., “RF-power and the Ring-Mode to Red-Mode Transition in an Inductively Coupled Plasma,” Journal of Applied Physics, Vol. 111, No. 8, pp. 083304–083311 (2012).
J. S. Cha and E. Fong, “A Method for Estimating Cryogenic Cooling Load in an Infrared Payload,” AIP Conference Proceedings, Vol. 1434, pp. 623–630 (2011).
K. Chan, “Miss Distance—Generalized Variance Non-Central Chi Distribution,” 21st AAS/AIAA Space Flight Mechanics Meeting (New Orleans, LA, 2011).
A. Chin and C. Clark, “Class F GaN Power Amplifiers for CubeSat Communication Links,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
T. G. Chrien et al., “Large Format Imaging Spectrometers for Future Hyperspectral Landsat Mission,” Imaging Spectrometry XVI (San Diego, CA, 2011).
A. B. Christensen, R. L. Bishop, J. H. Hecht, et al., “Characterization of Sensitivity Degradation Seen from the UV to NIR by RAIDS on the International Space Station,” Solar Physics and Space Weather Instrumentation IV (San Diego, CA, 2011).
A. B. Christensen, R. L. Bishop, J. H. Hecht, et al., “Observations of Molecular Oxygen Atmospheric Band Emission in the Thermosphere Using the Near Infrared Spectrometer on the ISS/RAIDS Experiment,” Journal of Geophysical Research, Space Physics, Vol. 117, No. A4 (Apr. 24, 2012).
M. R. Ciofalo and M. J. Meshishnek, “Air-Induced Recovery of Proton-Exposed Space Materials,” Journal of Spacecraft and Rockets, Vol. 49, No. 4, pp. 757–765 (Aug. 2012).
S. G. Claudepierre et al., “Dependence of the Amplitude of Pc5-Band Magnetic Field Variations on the Solar Wind and Solar Activity,” Journal of Geophysical Research, Vol. 117, No. A4, pp. A04207.1–A04207.18 (2012).
J. H. Clemmons et al., “High-Latitude E Region Ionosphere-Thermosphere Coupling: A Comparative Study Using In Situ and Incoherent Scatter Radar Observations,” Journal of Geophysical Research, Vol. 117, No. A2, pp. A02301.1–A02301.11 (2012).
J. H. Clemmons et al., “Strong Magnetic Field Fluctuations Within Filamentary Auroral Density Cavities Interpreted as VLF Saucer Sources,” Journal of Geophysical Research, Vol. 117, No. A2, pp. A02217.1–A02217.11 (2012).
J. G. Coffer and J. C. Camparo, “Radio Frequency-Power and the Ring-Mode to Red-Mode Transition in an Inductively Coupled Plasma,” Journal of Applied Physics, Vol. 111, No. 8 (2012).
S. A. Cota, T. S. Lomheim, C. J. Florio, J. M. Harbold, B. M. Muto, R. B. Schoolar, et al., “PICASSO—An End-to-End Image Simulation Tool for Space and Airborne Imaging Systems: II. Extension to the Thermal Infrared—Equations and Methods,” Imaging Spectrometry XVI (San Diego, CA, 2011).
K. B. Crawford, D. Goldstein, D. Gutierrez, et al., “LCROSS (Lunar Crater Observation and Sensing Satellite) Observation Campaign: Strategies, Implementation, and Lessons Learned,” Space Science Reviews, Vol. 167, No. 1–4, pp. 93–140 (2012).
E. Deionno et al., “A Solid-State Switch Containing an Electrochemically Switchable Bistable Poly[n]rotaxane,” Journal of Materials Chemistry, Vol. 21, No. 5, pp. 1487–1495 (2011).
F. J. De Luccia, D. Moyer, et al., “Comparison of VIIRS Pre-launch RVS Performance Using Results from Independent Studies,” Earth Observing Systems XVI (San Diego, CA, 2011).
F. Di Teodoro et al., “Coherent Combining of Pulsed Fiber Amplifiers in the Nonlinear Chirp Regime with Intra-Pulse Phase Control,” Optics Express, Vol. 20, No. 7, pp. 7422–7435 (2012).
R. B. Dybdal et al., “Narrow Beamwidth Satellite Antenna Pointing and Tracking,” 2011 IEEE International Symposium on Antennas and Propagation—Proceedings (Spokane, WA, 2011).
R. B. Dybdal et al., “Wide Scanning Reflector Antennas for Satellite Crosslinks,” 2011 IEEE International Symposium on Antennas and Propagation—Proceedings (Spokane, WA, 2011).
R. B. Dybdal, S. J. Curry, F. Lorenzelli, and D. J. Hinshilwood, “Multiple Polarization Communications,” Antennas and Propagation Society International Symposium (APSURSI), 2012 IEEE, pp. 1–2 (Chicago, IL, 2012).
J. S. Fant, H. Gomaa, and R. G. Pettit, “A Comparison of Executable Model Based Approaches for Embedded Systems,” 2012 2nd International Workshop on Software Engineering for Embedded Systems, Proceedings (Zurich, Switzerland, 2012).
J. S. Fant, H. Gomaa, and R. G. Pettit, “Software Product Line Engineering of Space Flight Software,” 3rd International Workshop on Product Line Approaches in Software Engineering, Proceedings (Zurich, Switzerland, 2012).
R. W. Farley, M. E. Rogers, B. J. Foran, et al., “Subnanosecond Bulk Damage Thresholds of Single-Crystal YAG and Diffusion-Bonded YAG Structures at 1 Micron,” Laser-Induced Damage in Optical Materials: 2011 (Boulder, CO, 2011).
R. A. Fields, D. A. Kozlowski, H. T. Yura, R. L. Wong, J. M. Wicker, et al., “5.625 Gbps Bidirectional Laser Communications Measurements Between the NFIRE Satellite and an Optical Ground Station,” Unmanned/Unattended Sensors and Sensor Networks VIII (Prague, Czech Republic, 2011).
B. Foran et al., “Nanopatterned Quantum Dot Active Region Lasers on InP Substrates,” Novel In-Plane Semiconductor Lasers X (San Francisco, CA, 2011).
P. Garnavich et al., “The Transitional Stripped-Envelope SN 2008ax: Spectral Evolution and Evidence for Large Asphericity,” Astrophysical Journal, Vol. 739, No. 1, pp. 41–63 (2011).
C. M. Gee, G. Sefler, P. T. Devore, and G. C. Valley, “Spurious-Free Dynamic Range of a High-Resolution Photonic Time-Stretch Analog-to-Digital Converter System,” Microwave and Optical Technology Letters, Vol. 54, No. 11, pp. 2558–2563 (2012).
J. Geis, J. Lang, L. Peterson, F. Roybal, J. Tanzillo, D. Thomas, and D. Warren, “Concurrent Engineering of an Infrared Telescope System,” Optical Modeling and Performance Predictions V (San Diego, CA, 2011).
J. L. Hall, R. H. Boucher, D. J. Gutierrez, S. J. Hansel, B. P. Kasper, E. R. Keim, N. M. Moreno, M. L. Polak, M. G. Sivjee, D. M. Tratt, and D. W. Warren, “First Flights of a New Airborne Thermal Infrared Imaging Spectrometer with High Area Coverage,” Infrared Technology and Applications XXXVII (Orlando, FL, 2011).
J. L. Hall, J. Qian, M. L. Polak, K. Westerberg, C. S. Chang, et al., “Characterization of Aerosol-Containing Chemical Simulant Clouds Using a Sensitive, Thermal Infrared Imaging Spectrometer,” Chemical, Biological, Radiological, Nuclear, and Explosives Sensing XII (Orlando, FL, 2011).
T. J. Hall, C. N. Mutchler, R. N. Thessin, et al., “Performance of Observation-Based Prediction Algorithms for Very Short-Range, Probabilistic Clear-Sky Condition Forecasting,” Journal of Applied Meteorology and Climatology, Vol. 50, No. 1, pp. 3–19 (2011).
S. R. Halper and E. W. Coir, “Development of a Practical Visual Indicator Tape for Adhesive and Coating Analysis,” International Journal of Adhesion and Adhesives, Vol. 31, No. 6, pp. 473–477 (Sep. 2011).
S. R. Halper and R. M. Villahermosa, “Comparative Evaluation of the Moisture Permeation of Polyurethane, Polyethylene, and Fluoropolymer Tubing,” Journal of Testing and Evaluation, Vol. 39, No. 4 (2011).
J. Hant, B. Wood, et al., “Calculating Call Blocking and Utilization for Communication Satellites That Use Dynamic Resource Allocation,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
J. Hashimoto, R. Russell, et al., “Discovery of Small-Scale Spiral Structures in the Disk of SAO 206462 (HD 135344B): Implications for the Physical State of the Disk from Spiral Density Wave Theory,” The Astrophysical
Journal, Vol. 748, No. 2, pp. L22.1–L22.7 (2012).
J. H. Hecht, J. H. Clemmons, R. L. Walterscheid, et al., “A Multiyear (2002–2006) Climatology of O/N2 in the Lower Thermosphere from TIMED GUVI and Ground-Based Photometer Observations,” Journal of Geophysical Research, Space Physics, Vol. 117, No. A3 (2012).
M. Hecht, A. Lam, and C. Vogl, “A Tool Set for Integrated Software and Hardware Dependability Analysis Using the Architecture Analysis and Design Language (AADL) and Error Model Annex,” 16th IEEE International Conference on Engineering of Complex Computer Systems, 2011 (Las Vegas, NV, 2011).
H. Helvajian et al., “Characteristics of Laser Absorption and Welding in FOTURAN Glass by Ultrashort Laser Pulses,” Optics Express, Vol. 19, No. 23, pp. 22961–22973 (2011).
S. Hensley, N. Marechal, L. Weintraub, R. Dickinson, R. Bloom, G. Karamyan, et al., “GSSR High Resolution Imagery and Topography of the Lunar South Pole Region,” Forty-Second Lunar and Planetary Science Conference (Woodlands, TX, 2011).
S. Herrin, L. Berenberg, and R. Musani, “DOD Space Test Program Multipayload Launch Mission Management,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
C. A. Hill, “Satellite Battery Technology—A Tutorial and Overview,” IEEE Aerospace and Electronic Systems Magazine, Vol. 26, No. 6, pp. 38–43 (2011).
A. R. Hopkins et al., “Small Angle Neutron Scattering (SANS) Characterization of Electrically Conducting Polyaniline Nanofiber/Polyimide Nanocomposites,” Thin Solid Films, Vol. 520, No. 5, pp. 1617–1620 (2011).
A. R. Hopkins, D. C. Straw, et al., “Influence of Surface Chemistry on Inkjet Printed Carbon Nanotube Films,” Thin Solid Films, Vol. 520, No. 5, pp. 1541–1545 (2011).
D. X. Houston, “Elements of a Generalized Duration Forecasting Model of Test-and-Fix Cycles,” 2012 International Conference on Software and System Process, ICSSP 2012 Proceedings (Zurich, Switzerland, 2012).
D. X. Houston, “Research and Practice Reciprocity in Software Process Simulation,” 2012 International Conference on Software and System Process, ICSSP 2012, Proceedings (Zurich, Switzerland, 2012).
M. Huang and J. C. Camparo, “Coherent Population Trapping under Periodic Polarization Modulation: Appearance of the CPT Doublet,” Physical Review A, Atomic, Molecular, and Optical Physics, Vol. 85, No. 1 (2012).
M. Huang, J. C. Camparo, et al., “Self-Pulsing in Alkali RF-Discharge Lamps,” 2012 IEEE International Frequency Control Symposium, IFCS, Proceedings (Baltimore, MD, 2012).
B. A. Jacoby et al., “The Timing of Nine Globular Cluster Pulsars,” The Astrophysical Journal, Vol. 745, pp. 109.1–109.12 (2012).
A. B. Jenkin, J. P. McVey, and B. D. Howard, “Uncertainty in Lifetime of Highly Eccentric Transfer Orbits Due to Solar Resonances,” Advances in the Astronautical Sciences, Vol. 142, Part 3, pp. 3041–3057 (2011).
A. B. Jenkin, M. E. Sorge, G. E. Peterson, J. P. McVey, and B. B. Yoo, “100-Year Low Earth Orbit Debris Population Model,” Advances in the Astronautical Sciences, Vol. 142, Part 1, pp. 139–157 (2011).
D. C. Judnick, “Simple Concurrent Engineering Methodology Tool for Large Architectural Tradespace Exploration,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
S. Kasemsan et al., “An Adaptive Slope Compensation for the Single-Stage Inverter With Peak Current-Mode Control,” IEEE Transactions on Power Electronics, Vol. 26, No. 10, pp. 2857–2862 (2011).
J. Kasper, J. B. Blake, J. Mazur, et al., “Observed and Simulated LET Spectra Comparison for the CRaTER Instrument on LRO,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
J. A. Kechichian, “Analytic Expansions of Luni-Solar Gravity Perturbations Along Rotating Axes for Trajectory Optimization—Part 1: The Dynamic System,” Acta Astronautica, Vol. 68, No. 11–12, pp. 1947–1963 (2011).
J. A. Kechichian, “Analytic Expansions of Luni-Solar Gravity Perturbations Along Rotating Axes for Trajectory Optimization—Part 2: The Multipliers System and Simulations,” Acta Astronautica, Vol. 68, No. 11–12, pp. 1914–1930 (2011).
J. A. Kechichian, “Fourth Order Expansions of the Luni-Solar Gravity Perturbations Along Rotating Axes for Trajectory Optimization,” Advances in the Astronautical Sciences, Vol. 140, pp. 1963–1982 (2011).
K. C. Kipp, S. C. Ringler, E. L. Chapman, et al., “Impact of Instrument Schedule Growth on Mission Cost and Schedule Growth for Recent NASA Missions,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
R. Koga, J. George, S. Bielat, and P. Yu, “Single Event Sensitivity of High-Speed Differential Signaling Devices to Heavy Ions and Protons,” 2011 IEEE Radiation Effects Data Workshop (Las Vegas, NV, 2011).
T. J. Kopp et al., “Tackling the Hydra, Validation of the Imagery Environmental Data Record (EDR) and Cloud Mask,” Geoscience and Remote Sensing Symposium (IGARSS), 2012 IEEE International (Munich, Germany, 2012).
J. K. Kreng and M. M. Ardeshiri, “Effects of Unanticipated VSWR Reflection and Delay on Range Correlation Performance,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
D. Kunkee, P. Gamba, et al., “Foreword to the Special Issue on the 2010 International Geoscience and Remote Sensing Symposium,” Geoscience and Remote Sensing, IEEE Transactions, Vol. 49, No. 12, pp. 4683–4685 (Dec. 2011).
T. Lam and E. Fong, “Heat Diffusion vs. Wave Propagation in Solids Subjected to Exponentially Decaying Heat Source: Analytical Solution,” International Journal of Thermal Sciences, Vol. 50, No. 11, pp. 2104–2116 (2011).
C. A. Lee, S. D. Gasster, et al., “Recent Developments in High Performance Computing for Remote Sensing: A Review,” IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, Vol. 4, No. 3, pp. 508–527 (2011).
J. H. Lee et al., “THEMIS Observations and Modeling of Multiple Ion Species and EMIC Saves: Implications for a Vanishing He SUP + Stop Band,” Journal of Geophysical Research, Vol. 117 No. A6, pp. A06204.1–A06204.13 (2012).
S. D. La Lumondiere, Y. Sin, W. T. Lotshaw, S. C. Moss, et al., “Characteristics of Step-Graded InxGa1-xAs and InGaPySb1-y Metamorphic Buffer Layers on GaAs Substrates,” 2011 Compound Semiconductor Week (CSW) and 23rd International Conference on Indium Phosphide and Related Materials (Berlin, Germany, 2011).
S. D. La Lumondiere, Y. Sin, W. T. Lotshaw, S. C. Moss, et al., “Narrow Band Gap (1 eV) InGaAsSbN Solar Cells Grown by Metalorganic Vapor Phase Epitaxy,” Applied Physics Letters, Vol. 100, No. 12, pp. 121120–121124 (2012).
J. R. Lince et al., “Microtribological Performance of Au-MOS SUB 2 Nanocomposite and Au/MoS SUB 2 Bilayer Soatings,” Tribology International, Vol. 52, pp. 144–152 (2012).
D. L. Liu, S. H. Liu, C. J. Panetta, S. M. Hong, K. R. Olson,
D. R. Alaan, C. J. Mann, and K. T. Luey, “Synergistic Effects of Contamination and Low Energy Space Protons on Solar Cell Current Output,” 37th IEEE Photovoltaic Specialists Conference (Seattle, WA, 2011).
L. Lubo, R. Herm, M. Jacobs, A. Amram, E. Sundberg, I. Min, M. Broder, T. Lomheim, and T. Hayhurst, “Decision Support Framework: Architecture Development,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
D. K. Lynch, R. W. Russell, et al., “Variability of Disk Emission in Pre-main Sequence and Related Stars. II. Variability in the Gas and Dust Emission of the Herbig Fe Star Sao 206462,” Astrophysical Journal, Vol. 745, No. 1, pp. 29–42 (2012).
V. N. Mahajan, “Orthonormal Aberration Polynomials for Anamorphic Optical Imaging Systems with Circular Pupils,” Applied Optics, Vol. 51, No. 18, pp. 4087–4091 (2012).
E. M. Mahr and R. E. Bitten, “Evaluating Options for Enhancing Technology Development and Controlling Cost Growth,” Geoscience and Remote Sensing Symposium (IGARSS), 2012 IEEE International, pp. 5654–5657 (2012).
M. Mason, N. Presser, Y. Sin, B. Foran, and S. C. Moss, “Electron Beam Induced Current Characterization of Dark Line Defects in Failed and Degraded High Power Quantum Well Laser Diodes,” 49th International Reliability Physics Symposium (Monterey, CA, 2011).
J. E. Mazur, J. F. Fennell, J. L. Roeder, P. T. O’Brien, T. B. Guild, and J. J. Likar, “The Timescale of Surface-Charging Events,” IEEE Transactions on Plasma Science, Vol. 40, No. 2, Part 1, pp. 237–245 (2012).
J. A. Mazzei, T. M. Cooney, et al., “A New Opportunity for Unmanned Aerial Systems (UAS) via Commercial Ka-band Satellites,” MILCOM 2011 (Baltimore, MD, 2011).
J. P. McVeu and C. C. Chao, “Automated Ballistic Coefficient Estimation Technique to Analyze the Debris from the Cosmos-2251 and Iridium-33 Collision,” Advances in the Astronautical Sciences, Vol. 142, Part 1, pp. 173–186 (2011).
D. Moyer et al., “VIIRS F1 ‘Best’ Relative Spectral Response Characterization by the Government Team,” Earth Observing Systems XVI (San Diego, CA, 2011).
D. Moyer, E. Haas, F. De Luccia, K. Rausch, et al., “NPP VIIRS Early On-Orbit Solar Diffuser Degradation Results,” Geoscience and Remote Sensing Symposium (IGARSS), 2012 IEEE International, pp. 1030–1033 (Munich, Germany, 2012).
T. Mulligan et al., “Ionic Composition Structure of Coronal Mass Ejections in Axisymmetric Magnetohydrodynamic Models,” Astrophysical Journal, Vol. 740, No. 2 (2011).
E. A. Nguyen and A. G. Ellis, “Experiences with Assurance Cases for Spacecraft Safing,” Proceedings—22nd IEEE International Symposium on Software Reliability Engineering 2011 (Hiroshima, Japan, 2011).
S. R. Nuccio et al., “640 Gb/s All-Optical Regenerator Based on a Periodically Poled Lithium Niobate Waveguide,” Journal of Lightwave Technology, Vol. 30, No. 9–12, pp. 1829–1834 (2012).
S. R. Nuccio et al., “Electro-Optic Polymer Modulators,” 2012 OFC Collocated National Fiber Optic Engineers (Los Angeles, CA, 2012).
M. J. O’Brien, A. L. De La Cruz, et al., “A Novel Proof Test for Silicon Nitride Balls,” Journal of the American Ceramic Society, Vol. 94, No. 2, pp. 597–604 (2011).
A. O. Okorogu et al., “Photorefractive Amplification at High Frequencies,” Practical Holography XXV: Materials and Applications (San Francisco, CA, 2011).
G. Peterson, “Effect of Future Space Debris on Mission Utility and Launch Accessibility,” Advances in the Astronautical Sciences, Vol. 142, Part 1, pp. 201–216 (2011).
P. R. Popick et al., “The United States Department of Defense Revitalization of System Security Engineering Through Program Protection,” 2012 6th Annual IEEE Systems Conference (Vancouver, BC, Canada, 2012).
G. Radhakrishnan, J. D. Cardema, P. M. Adams, H. I. Kim, and B. Foran, “Fabrication and Electrochemical Characterization of Single and Multilayer Graphene Anodes for Lithium-ion Batteries,” Journal of the Electrochemical Society, Vol. 159, No. 6, pp. A752–A761 (2012).
S. H. Raghavan and T. C. Powell, “Upper Bound on C/A and L1C Code Spectral Separation Coefficients,” 2011 IEEE Aerospace Conference (Big Sky, MT, 2011).
S. H. Raghavan and L. Williams, “Modulation Loss Analysis for Amplitude Modulated FSK Signal,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
K. Rausch, F. De Luccia, D. Moyer, J. Cardema, et al., “SUOMI NPP VIIRS Reflective Solar Band Radiometric Calibration,” Geoscience and Remote Sensing Symposium (IGARSS), 2012 IEEE International, pp. 1050–1052 (2012).
J. A. Roden et al., “A Discontinuous Galerkin Finite Element Time-Domain Method Modeling of Dispersive Media,” IEEE Transactions on Antennas and Propagation, Vol. 60, No. 4, pp. 1969–1977 (2012).
R. W. Russell, “Mid-infrared Spectrophotometric Observations of Fragments B and C of Comet 73p/Schwassmann-Wachmann 3,” Astronomical Journal, Vol. 141, No. 1, pp. 26–38 (2011).
P. M. Schubel, “Response and Damage Tolerance of Composite Sandwich Structures under Low Velocity Impact,” Experimental Mechanics, Vol. 52, No. 1, pp. 37–47 (2012).
G. A. Sefler, “Photonic Ultra-Wideband Transmitter Using a Chirped Heterodyne Technique,” IEEE Photonics Technology Letters, Vol. 24, No. 2, pp. 128–130 (2012).
G.A. Sefler, G. C. Valley, et al., “Demonstration of a Large Stretch-Ratio Photonic Analog-to-Digital Converter With 8 ENOB for an Input Signal Bandwidth of 10 GHz,” IEEE Photonics Technology Letters, Vol. 24, No. 14, pp. 1185–1187.
Y. Sin, B. Foran, et al., “Quantum Dot Active Regions Based on Diblock Copolymer Nanopatterning and Selective MOCVD Growth,” 2011 IEEE Winter Topicals (Keystone, CO, 2011).
Y. Sin, S. D. La Lumondiere, B. J. Foran, W. T. Lotshaw, S. C. Moss, et al., “Carrier Dynamics and Defects in MOVPE-Grown Bulk InGaAs Layers with Metamorphic InGaAs and InGaPSb Buffer Layers for Solar Cells,” Physics and Simulation of Optoelectronic Devices XX (San Francisco, CA, 2012).
Y. Sin, S. D. La Lumondiere, W. T. Lotshaw, N. Ives, S. C. Moss, et al., “Carrier Dynamics in Catastrophic Optical Bulk Damaged InGaAs-AlGaAs Strained QW Broad-Area Lasers,” 2011 Conference on Lasers and Electro-Optics (Baltimore, MD, 2011).
Y. Sin, S. D. La Lumondiere, N. Presser, B. Foran, N. Ives, W. Lotshaw, S. Moss, et al., “Physics of Failure Investigation in High-Power Broad-Area InGaAs-AlGaAs Strained Quantum Well Lasers,” High-Power Diode Laser Technology and Applications X (San Francisco, CA, 2012).
Y. Sin, W. T. Lotshaw, S. C. Moss, et al., “Carrier Dynamics in MOVPE-Grown Bulk Dilute Nitride Materials for Multi-Junction Solar Cells,” Physics and Simulation of Optoelectronic Devices XIX (San Francisco, CA, 2011).
Y. Sin, W. T. Lotshaw, S. C. Moss, et al., “Characteristics of Bulk InGaAsN and InGaAsSbN Materials Grown by Metal Organic Vapor Phase Epitaxy (MOVPE) for Solar Cell Application,” Physics and Simulation of Optoelectronic Devices XX (San Francisco, CA, 2012).
Y. Sin, N. Presser, N. Ives, W. Lotshaw, S. Moss, et al., “Catastrophic Optical Bulk Damage (COBD)—A New Degradation Mode in High Power InGaAs-AlGaAs Strained QW Lasers,” Semiconductor Laser Conference (ISLC), 2012 IEEE International, pp. 116–117 (San Diego, CA, 2012).
P. Smith, M. Ferringer, R. Kelly, and I. Min, “Budget-Constrained Portfolio Trades Using Multiobjective Optimization,” Journal of Systems Engineering, Vol. 15, No. 4, pp. 461–470 (2012).
E. B. Song, M. Mecklenburg, B. H. Weiller, et al., “Atomic-Scale Characterization of Graphene Grown on Copper (100) Single Crystals,” Journal of the American Chemical Society, Vol. 133, No. 32, pp. 12536–12543 (2011).
R. Speelman, “Tradeoff Between Loop Update Rate and Loop Bandwidth for Low Data Date Communications in the Presence of Phase Noise,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
S. Sud, “Joint Synchronization in the CDMA Reverse Link Using a Two-Bit Window Transpose Domain Filter,” 2012 IEEE International Conference on Emerging Signal—Proceedings (Las Vegas, NV, 2012).
H. Tan, R. Liang, and J. Han, “Physical Layer Network Coding for Information Exchange over a Relay Node,” 5th International Conference on Signal Processing and Communication Systems—Proceedings (Honolulu, HI, 2011).
T. Turflinger et al., “LEO Protons on Selected Optical Fibers,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
R. E. Tuttle, J. S. Hwung, and J. A. Lollock, “Identifying Goals for Ares 1-X Modal Testing,” 28th IMAC, A Conference on Structural Dynamics, 2010 (Jacksonville, FL, 2010).
G. C. Valle et al., “Error Analysis and Implementation Considerations of Decoding Algorithms for Time-Encoding Machine,” EURASIP Journal on Advances in Signal Processing, pp. 1–10 (2011).
D. Walker, C. J. Mann, J. C. Nocerino, and S. H. Liu, “Proton Irradiation of Metallic Single-Walled Carbon Nanotubes,” 37th IEEE Photovoltaic Specialists Conference (Seattle, WA, 2011).
D. Walker, C. J. Mann, C. J. Panetta, D. R. Alaan, A. R. Hopkins, and S. H. Liu, “Controlling the Doping of Single-Walled Carbon Nanotube Networks by Proton Irradiation,” Applied Physics Letters, Vol. 101, No. 10, pp. 103111–103115 (2012).
R. L. Walterscheid et al., “Decadal Variations in a Venus General Circulation Model,” Icarus, Vol. 212, No. 1, pp. 42–65 (2011).
R. L. Walterscheid, L. J. Gelinas, et al., “Evaluation of Momentum and Sensible Heat Fluxes in Constant Density Coordinates: Application to Superpressure Balloon Data During the VORCORE Campaign,” Journal of Geophysical Research, Vol. 117, No. D9, pp. D09105.1–D09105.15 (20112).
R. L. Walterscheid and M. P. Hickey, “Gravity Wave Propagation in a Diffusively Separated Gas: Effects on the Total Gas,” Journal of Geophysical Research, Vol. 117, No. A5 (2012).
D. W. Webb, E. M. Lim, J. S. Cha, and S. W. K. Yuan, “Modified Methodology for Technology Trending: Case Study of Cryocooler Efficiency,” Advances in Cryogenic Engineering: Cryogenic Engineering Conference (Spokane, WA, 2011).
L. A. Wickman and M. H. Clayson, “Environmental Changes and National Security Space Programs,” 2012 IEEE Aerospace Conference (Big Sky, MT, 2012).
J. Wilson, R. Martin, A. Terzuoli, E. Walton, A. Tubbs, et al., “Aerostat Communication Design,” 2012 15th International Symposium on Antenna Technology and Applied Electromagnetics (Toulouse, France, 2012).
J. Wilson, A. Terzuoli, A Tubbs, et al., “Spherical Antenna Design for Satellite Communications,” 2012 15th International Symposium on Antenna Technology and Applied Electromagnetics (Toulouse, France, 2012).
D. B. Witkin, “Creep Behavior of Bi-Containing Lead-Free Solder Alloys,” Journal of Electronic Materials, Vol. 41, No. 2, pp. 190–203 (2012).
D. B. Witkin, “Influence of Microstructure on Quasi-static and Dynamic Mechanical Properties of Bismuth-Containing Lead-Free Solder Alloys,” Materials Science and Engineering A, pp. 212–220 (Jan. 15, 2012).
H. T. Yura et al., “Selectivity of Spatial Filtering Velocimetry of Objective Speckles for Measuring Out-of-Plane Motion,” Optical Sensing and Detection II (Brussels, Belgium, 2012).
H. T. Yura et al., “Speckle and Fringe Dynamics in Imaging-Speckle-Pattern Interferometry for Spatial-Filtering Velocimetry,” Applied Optics, Vol. 50, No. 28, pp. 5577–91 (2011).
H. T. Yura and R. A. Fields, “Level Crossing Statistics for Optical Beam Wander in a Turbulent Atmosphere with Applications to Ground-to-Space Laser Communications,” Applied Optics, Vol. 50, No. 18, pp. 2875–2885 (2011).
H. T. Yura and D. A. Kozlowski, “Low Earth Orbit Satellite-to-Ground Optical Scintillation: Comparison of Experimental Observations and Theoretical Predictions,” Optics Letters, Vol. 36, No. 13, pp. 2507–2509 (2011).
H. T. Yura and T. S. Rose, “Exponentiated Weibull Distribution Family under Aperture Averaging for Gaussian Beam Waves,” Optics Express, Vol. 20, No. 12, pp. 20680–20683 (2012).
R. J. Zaldivar, P. M. Adams, J. P. Nokes, and H. I. Kim, “Surface Functionalization of Graphene-like Materials by Carbon Monoxide Atmospheric Plasma Treatment for Improved Wetting without Structural Degradation,” Journal of Vacuum Science and Technology B, Vol. 30, No. 3 (2012).
R. J. Zaldivar, H. I. Kim, G. L. Steckel, J. P. Nokes, and D. N. Patel, “The Effect of Abrasion Surface Treatment on the Bonding Behavior of Various Carbon Fiber-Reinforced Composites,” Journal of Adhesion Science and Technology, Vol. 26, No. 10–11, pp. 1573–1590 (2012).
R. J. Zaldivar, H. I. Kim, G. L. Steckel, D. Patel, B. A. Morgan, and J. P. Nokes, “Surface Preparation for Adhesive Bonding of Polycyanurate-Based Fiber-Reinforced Composites Using Atmospheric Plasma Treatment,” Journal of Applied Polymer Science, Vol. 120, No. 2, pp. 921–931 (2011).
R. J. Zaldivar, J. P. Nokes, P. M. Adams, K. Hammoud, and H. I. Kim, “Surface Functionalization without Lattice Degradation of Highly Crystalline Nanoscaled Carbon Materials Using a Carbon Monoxide Atmospheric Plasma Treatment,” Carbon, Vol. 50, No. 8, pp. 2966–2975 (2012).
R. J. Zaldivar, J. P. Nokes, D. N. Patel, B. A. Morgan, G. Steckel, and H. I. Kim, “Effect of Using Oxygen, Carbon Dioxide, and Carbon Monoxide as Active Gases in the Atmospheric Plasma Treatment of Fiber-Reinforced Polycyanurate Composites,” Journal of Applied Polymer Science, Vol. 125, No. 4, pp. 2510–2520 (2012).
R. J. Zaldivar, J. Salfity, G. Steckel, B. Morgan, D. Patel, J. P. Nokes, and H. I. Kim, “Bondability of TC410 Composites: The Surface Analysis and Wetting Properties of an Atmospheric Plasma-Treated Siloxane-Modified Cyanate Ester Composite,” Journal of Composite Materials, Vol. 46, No. 16, pp. 1925–1936 (2012).
R. P. Patera, “Systems and Methods for Attitude Propagation for a Slewing Angular Rate Vector,” U.S. Patent No. 8,185,261, July 2009
The attitude propagation of a vehicle can be determined accurately and easily if the angular rate vector points in a fixed direction with respect to the vehicle. However, most cases of interest involve angular rate vectors that change direction as a function of time. This invention is directed to computer-based systems and methods for propagating attitude for a moveable object (e.g., a space vehicle, a terrain vehicle, or other types of moveable objects). Since the slew rate of the angular rate vector causes attitude propagation error, this invention overcomes this problem by employing an additional coordinate frame that slews with the angular rate vector. In this new intermediate frame, the angular rate vector does not change direction and improves attitude propagation accuracy compared to prior attitude propagation techniques. For pure coning motion, this invention completely eliminates attitude propagation error.
H. G. Muller, H. I. Kim, and B. J. Foran, “Stable Lithium Niobate Waveguides, and Methods of Making and Using Same,” U.S. Patent No. 8,189,981, November 2009
Electrooptically active devices have conventionally been prepared using lithium niobate. However, lithium niobate waveguides prepared using conventional proton exchange techniques are vulnerable to performance degradation, limiting their application. The resulting waveguide may also be unstable due to stresses caused by the ion exchange process. This invention provides stable lithium niobate waveguides with improved stability and methods for making and using them. Specifically, the waveguides may be fabricated using a plurality of steps, each of which inhibits the formation of performance-degrading defects. For example, a high-refractive index layer may be prepared using a soft proton exchange on a lithium ion substrate, in which an excess of lithium ions are provided to slow the proton exchange reaction, allowing more time for the protons to diffuse into the substrate and thus reducing defect-inducing stress. Such a proton exchange step may be followed by an annealing step during which a predetermined vapor pressure of water is applied over the substrate. The vapor pressure of water may be selected to inhibit dehydration of the substrate, reducing the formation of defects, and provide a specified stoichiometric ratio of niobium to oxygen in the proton-exchanged layer.
D. S. Kun and N. Morgan, “Constant False Alarm Rate Robust Adaptive Detection Using the Fast Fourier Transform,” U.S. Patent No. 8,194,766, May 2009
Many conventional detectors are deficient in that their detection functionality depends on having an accurate estimate of the noise power. For example, some conventional detectors, under certain environments in which the signal-to-noise power ratio can change abruptly (e.g., wireless channels), cannot change their detection threshold without having to restart their numerical algorithm to estimate the noise power. This invention relates generally to signal detection and, in particular, to receivers and techniques that use the fast Fourier transform (FFT) to detect the presence of man-made signals and achieve a constant false alarm rate (CFAR) when only noise is present within a predetermined frequency band. The invention involves signal-detection techniques using FFT that instantaneously react to rapid changes in the signal while achieving a CFAR without resorting to calibration or collection methods to estimate the key statistical parameters of the environment in which the signal resides. The invention employs a decision rule that immediately adjusts to power fluctuations, which overcomes the disadvantage of prior signal-detection techniques of being unable to adapt immediately to abrupt changes in the environment. The invention derives the probability distribution of the decision statistic that results in a detection threshold that is independent of the noise variance, FFT window type, and the statistics of the environment.
R. B. Dybdal, S. J. Curry, F. Lorenzelli, et al., “Systems and Methods for Increasing Communications Bandwidth Using Non-Orthogonal Polarizations,” U.S. Patent No. 8,199,851, July 2011
Dual polarization system designs allow two independent signals to be communicated in the same bandwidth, thus doubling the signal throughput. Example applications include direct broadcast satellite TV that allows twice the number of channels to be sent to subscribers. Mutual interference between the independent signals is avoided by design attention to passively and actively maintaining polarization orthogonality. Further increases in communication throughput require communicating independent signals on nonorthogonal polarizations. Mutual interference in this case is avoided by joint signal separation techniques that allow the separation of the independent signals from the composite signals used in their communication. An example embodiment referred to as quadrapol communicates four independent signals using four nonorthogonal polarizations to increase the throughput by a factor of four, compared to the conventional dual polarization designs that double the communication throughput.
S. La Lumondiere and T. Yeoh, “Refraction Assisted Illumination for Imaging,” U.S. Patent No. 8,212,215, February 2012
One method of imaging through substrate material is conventional bright field microscopy. While this technique can be relatively inexpensive, the resolution of the resulting images is often disappointing. This invention is directed to systems and methods of imaging subsurface features of objects such as semiconductor devices. An illumination source may be directed toward a surface of an object comprising subsurface features, wherein the illumination from the source is directed at a first angle relative to the normal of the surface. The object may have a portion between the subsurface features and the surface, which has an index of refraction that is greater than the index of refraction of a surrounding medium that surrounds the object. An imaging device may be placed with an objective lens oriented substantially normal to the surface. The first angle may be larger than an acceptance angle of the objective lens.
T. S. Yeoh and N. A. Ives, “Isosurfacial Three-Dimensional Imaging System and Method,” U.S. Patent No. 8,217,937, March 2007
Isosurfacial reconstruction methods reconstruct exterior surfaces of objects. However, a limitation of the isosurfacial technique is the lack of information of interior surfaces underneath exterior surfaces and exterior structures. This invention is directed to a three-dimensional isosurfacial imaging system and method for imaging objects that may have obscure interior surfaces hidden from exterior views. The system captures a series of tilt images that are used to reconstruct an isosurface of the object that is a three-dimensional model image. The system then processes the series of tilt images using enhanced tomographic computations. The system can apply a special case in computer-aided tomography that assumes complete transmission or complete absorption in order to compute the density micrograph.
F. Lorenzelli, “Signal Separator,” U.S. Patent No. 8,218,692,
Techniques modifying transmitted signals to aid subsequent separation are the workhorses of modern-day communications, and it is their improvement that has dominated signal separation research and development. This invention relates to a device and process for separating digital signals embedded in a single received signal. The signal separation device and method of the invention include embodiments for separating uncoordinated cochannel signals of comparable power from a single received signal impaired by intersymbol interference, mutual interference, and additive noise. The method comprises the following steps: implementing an initial channel estimator, a blind maximum likelihood symbol detector, and a least-squares channel estimator in one or more digital processors; converting the received signal in an analog-to-digital converter, the sample rate of the converter exceeding the symbol rate by a factor greater than or equal to two; utilizing the initial channel estimator to make an initial set of channel estimates from the converted received signal; producing a data block by decimating the converted received signal; detecting symbols from the data block in a multisignal trellis of the maximum likelihood symbol detector using the most recent channel estimates; utilizing the least-squares channel estimator to make another set of channel estimates from the detected symbols; returning to the detecting step if the channel estimates have not converged; comparing the trellis end survivors’ metrics to determine if the detected symbols should be accepted; returning to the first utilizing step and revising the initial channel state information if the detected symbols are not accepted; and accepting the detected symbols and returning to the producing step if data remains.
J. K. Fuller, “Stereolithographic Rocket Motor Manufacturing Method,” U.S. Patent No. 8,225,507, February 2008
Hybrid rocket motors use reactants of different physical phase states, usually a solid fuel such as rubber and a gaseous oxidizer such as nitrous oxide. While hybrid motors do not generally deliver the performance of liquid motors, they are safer and simpler to build and operate. Ideally, hybrid motors can have very good performance, but the real-world problems of maintaining an optimal oxidizer-to-fuel ratio and slow-burning fuels have limited their use to niche applications. This invention is directed to a hybrid rocket motor, including a fuel grain, that is created by printing a fuel material using rapid-prototyping techniques. A grain can be manufactured by photopolymerizing the solid fuel in a stereolithography rapid-prototyping type machine. Fuel grains made with rapid-prototyping techniques can be made of almost any shape. These grains can have improved performance by including port shapes and features that promote mixing and increase the amount of burning surface. Many of these port shapes could not be produced with traditional fabrication techniques.
R. P. Welle, “Phase-Change Valve Apparatuses,” U.S. Patent No. 8,240,336, April 2010
Developments in miniaturization and large-scale integration in fluidics have led to the concept of creating an entire chemistry or biology laboratory on integrated microfluidic devices. However, producing reliable valves has proven to be problematic with these devices. Thus, there has remained a need for a bistable phase-change valve that can remain in either an open or closed position, and in which there is a very low probability of phase-change material being lost from the valve. This invention relates generally to valves for controlling fluid flow and, in particular, to valves for microfluidic devices. The invention is an electrically actuated bistable valve (e.g., microvalve) that uses a phase-change control fluid to alternately block and unblock the flow of a working fluid through the valve. The control fluid is introduced from a side channel and is pumped into or out of a main flow channel when the control fluid is in a liquid state. The valve apparatus includes the following elements: a substrate, a main flow channel, a control channel, a biphase material within the control channel, a heating element adjacent the control channel and the junction, and a pumping mechanism.
N. A. Ives, C. Suen, M. S. Leung, et al., “Adaptive Membrane Shape Deformation System,” U.S. Patent No. 8,244,066, March 2008
The use of a lightweight antenna system is a desirable goal for space-based communication systems. A system that uses a lightweight polymeric material configured as a large sheet that may be greater than thirty meters in diameter has been proposed as a suitable candidate for such applications. However, there is a need to shape and maintain the sheet to reflect directed signals to act as an antenna. This invention is directed to a method for determining the shape of a flexible membrane and deforming a flexible deployable membrane. The method first captures three-dimensional shape data of a membrane that may be a flexible, deployable, space-based adaptive membrane antenna, and then determines the shape of the membrane. The determined membrane shape is compared to a desired shape and altered by actuation so that the membrane shape is deformed into the desired shape. The method can be applied to a system for maintaining the shape of the membrane to a desired shape. The system and method would include image capturing, image data processing, and activation beams for deforming the membrane shape into the desired shape.
R. P. Welle, “Microfluidic Devices with Separable Actuation and Fluid-Bearing Modules,” U.S. Patent No. 8,245,731,
A microfluidic device should be fully capable of manipulating multiple fluids, which includes a number of functions such as storage, transport, heating, cooling, and mixing. Although all these functions have been demonstrated with varying degrees of success on microfluidic devices, valves and pumps have typically been complex devices that are difficult to manufacture. Unfortunately, this leads to high fabrication costs, which generally make it impractical to manufacture the devices to be disposable. Thus, a need has existed for a microfluidic device that is capable of performing various manipulations on fluids while also being manufacturable in a manner suitable for the devices to be disposable. This invention is a microfluidic device that is provided by two operatively interfaced modules, namely a fluid-bearing module and an actuator module. The fluid-bearing module incorporates fluid transport and containment elements as well as other elements that may come into contact with fluids. The actuator module incorporates actuation mechanisms for fluid transport and control. The two modules are brought together into contact for use. The modules are detachably secured to each other, thereby allowing the fluid-bearing module to be separated from the actuator module and disposed of. On the other hand, the actuator module is reusable with another fluid-bearing module, eliminating in many instances the possibility of cross-contamination between fluids in the two fluid-bearing modules.
M. J. Lange, “High Power Waveguide Polarizer with Broad Bandwidth and Low Loss, and Methods of Making and Using Same,” U.S. Patent No. 8,248,178, December 2009
Guided-wave polarizer technology converts a circularly polarized wave into a linear-polarized wave while maintaining orthogonality of the two possible senses of each polarized wave. However, prior art polarizers suffer from a number of deficiencies, including low bandwidth, high loss, low power-handling capability, and large size. This invention provides a compact waveguide polarizer that includes a hollow waveguide body and at least one ridge disposed along the interior of the waveguide body. Each ridge includes on its upper surface a plurality of spaced projections (e.g., cylindrical or rectangular posts) or serrations. The ridges and spaced projections together produce a broadband differential phase shift between two orthogonal modes propagating through the waveguide body. Specifically, the spaced projections provide a small capacitive reactance that offsets the inductive loading of the lower portions of the ridges. As a result, a mode propagating parallel to the ridges accumulates a phase delay relative to a mode propagating orthogonal to the ridges that is substantially independent of wavelength over a relatively wide bandwidth. The differential phase delay may easily be tuned by adjusting the length of the projections. The bandwidth of the polarizer may be enhanced by configuring the projections such that they are narrower than the ridges on which they are disposed. Additionally, the polarizers may be inexpensively fabricated, are compact, have no dielectric losses, may accept high power fields, and may be used in a wide variety of environmental conditions.
M. P. Ferringer, R. S. Clifton, and T. G. Thompson, “Systems and Methods for Parallel Processing Optimization for an Evolutionary Algorithm,” U.S. Patent No. 8,255,344,
The goal of multiple-objective optimization is to maximize or minimize multiple measures of performance simultaneously while maintaining a diverse set of Pareto-optimal solutions. Classical multiple-objective optimization techniques are advantageous if the decision maker has some prior knowledge of the relative importance of each objective. Because classical methods reduce the multiple-objective problem to a single objective, convergence proofs exist assuming traditional techniques are employed. But despite these advantages, real-world problems, such as satellite constellation design optimization, challenge the effectiveness of classical methods. According to this invention, the systems and methods for parallel-processing optimization may include the following: receiving an initial population of parent chromosome data structures; selecting pairs of parent chromosome data structures; applying at least one evolutionary operator to the genes of the selected pairs to generate a plurality of child chromosome data structures; allocating the generated plurality of child chromosome structures to a plurality of slave processors; receiving objective function values for a portion of the plurality of allocated child chromosome data structures; merging the parent chromosome data structures with the received portion of the child chromosome data structures; and identifying a portion of the merged set of chromosome data structures as an elite set of chromosome data structures.
R. B. Dybdal, F. Lorenzelli, and S. J. Curry, “Methods and Systems for Increased Communication Throughput,” U.S.
Patent No. 8,259,857, September 2012
Various technical and economic factors have led to a desire to increase communication throughput within a given frequency bandwidth. One approach, for example, utilizes higher-order signal modulation formats such as eight-phase shift keying and quadrature amplitude modulation to obtain greater bandwidth efficiency. Such modulation formats maximize the data transmitted in a given bandwidth, resulting in increased bandwidth efficiency. But one limitation of higher-order modulation is increased stringency on transmitter linearity resulting in transmitter power backoff requirements that reduce signal power for receiver detection and prompt the development of linearizers to allow operation closer to transmitter-saturated output levels. This invention is directed to systems and methods that use signal processing techniques to allow the frequency bandwidth to be shared among two or more independent data streams as a means to increase communication throughput. This invention allows the separation of the independent data streams from a composite signal comprised of the multiple independent data streams negating what would normally be unacceptable levels of cochannel interference or other interference for conventional receiving systems. In this way, multiple signal components may partially or completely share the same frequency bandwidth by applying signal separation techniques to obtain acceptable communication performance for each of the multiple signals. Several applications described in the patent describe potential increases in communication throughput that are achieved by applying signal processing techniques to a composite signal to communicate multiple independent data streams without the constraint imposed by passive design techniques to isolate the individual signal components.
J. Y. Kim, “Systems and Methods for Concurrently Emulating Multiple Channel Impairments,” U.S. Patent No. 8,265,921, September 2012
Wireless communications links are sometimes characterized by relatively high bit error rates, large delay-bandwidth products, variable round-trip times, asymmetric channels, and impairments caused by various expected and unexpected events such as weather, fading, blockage, or jamming. In order to test the functionality and performance of next-generation wireless networks, it is important to have the ability to emulate communication applications in real time over communications links with similar characteristics. Thus, there is a need for systems and methods for concurrently emulating multiple channel impairments. This invention describes a multichannel emulator system. The system may include a memory that stores a plurality of channel impairment profiles, where each channel impairment profile corresponds to a respective channel impairment type, a real-time clock that generates timing data, and a processor in communication with the memory and the real time clock. The processor may be configured to: receive a selection of two or more of the plurality of channel impairment profiles; generate a composite impairment profile by combining the selected two or more channel profiles, specifying time-variant impairments, or reflecting a combination of the respective impairment types of the selected channel profiles; and apply the time-variant impairments specified by the composite impairment profile to an input real-time data stream to generate an impaired real-time data stream, where a timing of the application of the time-variant impairments is based at least in part upon the timing data from the real-time clock.
M. T. Presley, “System and Method for Distributing Processing of a Single-Process Application Having First and Second Objects in a Network Having Local and Remote Processes,” U.S. Patent No. 8,266,201, September 2012
An object-oriented computer program contains interacting objects that carry out specific program logic. Single process programming techniques assume that all objects reside within the same process hosted on a single computer system. Distributed programming systems, on the other hand, are designed to support objects across multiple processes, usually hosted on separate computers. This invention overcomes the shortcomings of previous systems and methods of adapting single-process legacy systems and distributed applications by modifying object classes during load time. The systems and methods of this invention provide a computer method for distributive processing of an object on a plurality of processes. A computer system and method are provided for making modifications to run-time coding of object-oriented software that enables distributed execution. The method automatically modifies object class definitions as the objects are loaded into the executing process. More particularly, the code modifications cause instances of the classes to interact with a distributed run-time system that allows all objects to be migrated between processes. Because the class definitions are modified at run time, a programmer does not need to add any code for application distribution. Thus, no programmer expertise in distributed systems is necessary, or any a priori knowledge of the program flow.
Return to Spring 2013 Table of Contents