Recent Publications, Papers, and Patents by the Technical Staff
First published Spring 2012, Crosslink® magazine
L. R. Abramowitz et al., “U.S. Air Force’s SMC/XR SENSE NanoSat Program,” AIAA SPACE 2011 Conference and Exposition (Long Beach, CA, 2011).
K. L. Bellman, “Model-Based Design, Engineering, and Development: Advancements Mean New Opportunities for Space System Development,” AIAA SPACE 2011 Conference and Exposition (Long Beach, CA, 2011).
J. Betser, F. C. Belz, et al., “Novel Approaches to Space Cyber Situational Awareness,” AIAA SPACE 2011 Conference and Exposition (Long Beach, CA, 2011).
R. L. Bishop, A. B. Christensen, J. H. Hecht, et al., “The RAIDS experiment on the ISS: On-Orbit Performance,” Solar Physics and Space Weather Instrumentation IV, p. 12 (San Diego, CA, 2011).
W. D. Bjorndahl and M. S. Byers, “Redundancy Implementations and Consideration of Related Failures in Spacecraft Electronic Systems,” 2011 IEEE Aerospace Conference (Big Sky, MT, 2011).
J. C. Cardema, C. M. Klimcak, and A. R. Herrera, “Development of a Fine Track System for the Aerospace Laser Communications Testbed,” 21st AAS/AIAA Space Flight Mechanics Meeting, pp. 1363–1373 (New Orleans, LA, 2011).
W. T. Cerven, “Covariance Error Assessment, Correction, and Impact on Probability of Collision,” 21st AAS/AIAA Space Flight Mechanics Meeting, pp. 757–772 (New Orleans, LA, 2011).
D. Chen, P. M. Belden, T. S. Rose, and S. M. Beck, “Narrowband Er:YAG Nonplanar Ring Oscillator at 1645 nm,” Optics Letters, Vol. 36, No. 7, pp. 1197–1199 (2011).
M. R. Ciofalo, M. E. Brady, C. J. Panetta, and M. J. Meshishnek, “Low-Energy Electron Exposure of Space Materials,” Journal of Spacecraft and Rockets, Vol. 48, No. 6, pp. 931–941 (Nov. 2011).
N. C. Cohen, G. G. Richardson, S. K. Martinelli, and J. Betser, “Extending Satellite Lifetimes in Geosynchronous Orbit with Servicing,” AIAA SPACE 2011 Conference and Exposition (Long Beach, CA, 2011).
E. Deionno et al., “Impact of Alpha Particles on the Electrical Characteristics of TiO2 Memristors,” IEEE Transactions on Nuclear Science, Vol. 58, No. 6, pp. 2838–2844 (Dec. 2011).
F. J. De Luccia, D. I. Moyer, et al., “Comparison of VIIRS Pre-Launch RVS Performance Using Results from Independent Studies,” Proceedings of the SPIE—The International Society for Optical Engineering, Vol. 8153, p. 81530L (Aug. 2011).
K. D. Diamant, J. E. Pollard, M. W. Crofton, et al., “Thrust Stand Characterization of the NASA Evolutionary Xenon Thruster,” Journal of Propulsion and Power, Vol. 27, No. 4, pp. 777–785 (2011).
D. A. Ehrlich, P. C. Lu, J. D. Hoffman, et al., “Advantages of Rapid Prototyping for Hybrid Rocket Motor Fuel Grain Fabrication,” 47th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit (San Diego, CA, 2011).
B. U. Etefia and J. J. Hant, “Delay/Overhead Measurements for Circuit-Emulation Tunnels,” MILCOM 2011 (2011).
J. S. Fant, R. G. Pettit, et al., “Architectural Design Patterns for Flight Software,” Proceedings—2011 14th IEEE International Symposium on Object/Component/Service-Oriented Real-Time Distributed Computing Workshops, pp. 97–101 (Newport Beach, CA, 2011).
G. Fathi and J. C. Camparo, “The 2 SUP nd Harmonic Signal in Vapor-Cell Atomic Clocks,” Proceedings of SPIE—The International Society for Optical Engineering (Nov. 2011).
I. V. Filippenko, D. K. Lynch, R. J. Rudy, R. W. Russell, M. J. Silverman, et al., “The Transitional Stripped-Envelope SN 2008ax: Spectral Evolution and Evidence for Large Asphericity,” The Astrophysical Journal, Vol. 739, No. 1,
p. 1 (2011).
E. Fong and T. T. Lam, “Thermal Modeling of Laser Heating on an Si-InSb-Si Composite,” 42nd AIAA Thermophysics Conference (Honolulu, HI, 2011).
B. M. Gable et al., “CALPHAD Based Kinetic Monte Carlo Simulation of Clustering in Binary Al-Cu Alloy,” Philosophical Magazine, Vol. 91, No. 1-3, pp. 315–336 (2011).
P. Hantos, “Systems Engineering Perspectives on Technology Readiness Assessments in Software-Intensive System Development,” Journal of Aircraft, Vol. 48, No. 3, pp. 738–748 (2011).
M. E. Harmon et al., “Mapping of Glass Transition Temperatures in Carbon Fiber Polymer Matrix Composites,” Polymer Preprints, Vol. 52, No. 2, pp. 111–112 (2011).
J. K. Holmes and S. H. Raghavan, “Doppler Removal Losses Using Single-Side Band Frequency Shifting for Direct-Sequence BPSK Links,” 2011 IEEE Aerospace Conference, p. 9 (Big Sky, MT, 2011).
M. Honda, W. M. Jackson, R. W. Russell, B. Yang, et al., “EPOXI: Comet 103P/HARTLEY 2 Observations From a Worldwide Campaign,” Astrophysical Journal, Letters, Vol. 734, No. 1, p. L1 (June 2011).
F. R. Hoots and M. E. Sorge, “Satellite Breakup Parameter Determination,” Advances in the Astronautical Sciences, pp. 124–144 (Monterey, CA, 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 (Dec. 2011).
D. X. Houston et al., “Impact of Process Simulation on Software Practice: An Initial Report,” 2011 33rd International Conference on Software Engineering, pp. 1045–1056 (Honolulu, HI, 2011).
A. G. Hsu, B. S. Hardy, et al., “Non-Penetrative Blast-Induced Traumatic Brain Injury: Visualization of Representative Human Skull and Brain Response to Shock and Blast Loading,” 41st AIAA Fluid Dynamics Conference and Exhibit (Honolulu, HI, 2011).
M. Huang and J. C. Camparo, “The Influence of Laser Polarization Variations on CPT Atomic Clock Signals,” Proceedings of SPIE—The International Society for Optical Engineering (Nov. 2011).
A. B. Jenkin et al., “On the Effect of Considering More Realistic Particle Shape and Mass Parameters in MMOD Risk Assessments,” Advances in Space Research, Vol. 47, No. 6, pp. 1006–1019 (2011).
H. I. Kim, G. L. Steckel, B. A. Morgan, J. P. Nokes, and R. J. Zaldivar, “Mechanical and Chemical Effects of Atmospheric Plasma Treatment on Fiber-Reinforced Composites for Adhesive Bonding,” Proceedings of the Annual Meeting of the Adhesion Society (2011).
T. Kim, Y. Sin, B. J. Foran, et al., “Quantum Dot Active Regions Based on Diblock Copolymer Nanopatterning and Selective MOCVD Growth,” 2011 IEEE Winter Topicals, pp. 33–34 (Keystone, CO, 2011).
R. Koga et al., “Proton-Induced Single Event Upsets in 90nm Technology High Performance SRAM Memories,” 2011 IEEE Radiation Effects Data Workshop, p. 3 (Las Vegas, NV, 2011).
A. D. Kostic et al., “Optimized Acoustic Microscopy Screening for Multilayer Ceramic Capacitors,” Proceedings—Annual Reliability and Maintainability Symposium (Lake Buena Vista, FL, 2011).
J. K. Kreng and S. H. Raghavan, “Wideband Frequency Synthesis for Broadband Communications,” 2011 IEEE Aerospace Conference (Big Sky, MT, 2011).
T. T. Lam and E. Fong, “Application of Solution Structure Theorem to Non-Fourier Heat Conduction Problems: Analytical Approach,” International Journal of Heat and Mass Transfer, Vol. 54, No. 23–24, pp. 4796–4806 (2011).
C. A. Landauer, “There Is Nothing So Practical as a Good Theory,” 4th IEEE International Conference on Space Mission Challenges for Information Technology, pp. 184–191 (Palo Alto, CA, 2011).
C. A. Lee and S. D. Gasster, “Netcentric Proxies for On-Orbit Sensors,” CrossTalk, Vol. 24, No. 6, pp. 4–7 (Nov. 2011).
M. T. Lee, “Feasibility and Performance Analyses of Adapting Ethernet-Based Protocols in Space-Based Networks,” MILCOM 2011 (2011).
D. K. Lynch, R. W. Russell, et al., “Infrared Spectroscopy of Comet 73P/Schwassmann-Wachmann 3 Using the Spitzer Space Telescope,” Astronomical Journal, Vol. 142, No. 3, p. 80 (Sept. 2011).
A. J. Majamaki and J. W. Lee, “CFD Simulations of Launch Environment for Delta IV Vehicles at the SLC-6 Launch Pad,” 49th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition (Orlando, FL, 2011).
J. N. Martin et al., “Defining a Strategy for Development of Systems Capability in the Workforce,” Systems Engineering, Vol. 14, No. 2, pp. 141–153 (2011).
M. S. Mason, G. Eng, M. S. Leung, G. W. Stupian, and T. S. Yeoh, “Microanalysis for Tin Whisker Risk Assessment,” IEEE International Reliability Physics Symposium Proceedings, pp. 2G.3.1–2G.3.5 (Monterey, CA, 2011).
J. E. Mazur, W. R. Crain Jr., M. D. Looper, D. J. Mabry, J. B. Blake, et al., “New Measurements of Total Ionizing Dose in the Lunar Environment,” Space Weather, Vol. 9, No. 7 (July 2011).
B. A. Morgan, R. J. Zaldivar, H. I. Kim, G. L. Steckel, J. A. Chaney, and J. P. Nokes, “Effect of Isopropanol Rinse on Adhesion of Plasma-Treated Carbon-Fiber Reinforced Epoxy Composites,” Journal of Composite Materials, Vol. 45, No. 12, pp. 1331–1336 (2011).
J. A. Morgan, “Comparison of Bayesian Land Surface Temperature Algorithm Performance with Terra MODIS Observations,” International Journal of Remote Sensing, Vol. 32, No. 23, pp. 8139–8159 (Dec. 2011).
G. Moy, D. M. Blaty Jr., M. S. Farber, C. D. Nealy, et al., “Fusion of Radar and Satellite Target Measurements Sensors and Systems for Space Applications,” Proceedings of SPIE—The International Society for Optical Engineering (2011).
D. I. Moyer, F. J. De Luccia, et al., “Results From Solar Reflective Band End-to-End Testing for VIIRS F1 Sensor Using T-SIRCUS,” Proceedings of the SPIE—The International Society for Optical Engineering, Vol. 8153, p. 81530I (Aug. 2011).
H. G. Muller, A. D. Stapleton, B. J. Foran, G. Radhakrishnan, H. I. Kim, P. M. Adams, R. A. Lipeles, and P. Herman, “Reduction of Lattice Defects in Proton-Exchanged Lithium Niobate Waveguides,” Journal of Applied Physics, Vol. 110, No. 3 (Aug. 2011).
D. A. Nigg, O. K. Rossi, R. J. Abbott, and J. W. Evans, “FireSat Revisited: Investigations in Tradespace Exploration,” AIAA SPACE 2011 Conference and Exposition (Long Beach, CA, 2011).
J. P. Nokes, H. I. Kim, G. L. Steckel, B. A. Morgan, and R. J. Zaldivar, “Atmospheric Plasma as a Surface Treatment Technique for Bonding Composite Materials,” International SAMPE Technical Conference, p. 8 (Long Beach, CA, 2011).
N. Presser, G. W. Stupian, M. S. Leung, et al., “Fabrication and Characterization of RF Nanoantenna on a Nanoliter-Scale 3D Microcontainer,” Nanotechnology, Vol. 22, No. 45, p. 455303 (Nov. 2011).
G. Radhakrishnan, P. M. Adams, A. D. Stapleton, H. G. Muller, and B. J. Foran, “Large Single-Crystal Monolayer Graphene by Decomposition of Methanol,” Applied Physics, Vol. 105, No. 1, pp. 31–37 (2011).
S. H. Raghavan and J. K. Holmes, “Combined Signal Quantization and Doppler Removal Losses Using Single-Sideband Frequency Shifting for Direct-Sequence BPSK Links,” Institute of Navigation—International Technical Meeting 2011, pp. 973–981 (San Diego, CA, 2011).
C. L. Ranieri, “Hypersonic, Aerodynamically Controlled, Path Constrained Reentry Optimization in SOCS,” 21st AAS/AIAA Space Flight Mechanics Meeting, pp. 2025–2044 (New Orleans, LA, 2011).
J. A. Roden and T. C. Kramer, “The Convolutional PML for FDTD Analysis: Transient Electromagnetic Absorption from DC to Daylight,” IEEE International Symposium on Electromagnetic Compatibility, pp. 892–898 (Long Beach, CA, 2011).
T. S. Rose, C. M. Klimcak, D. A. Kozlowski, G. A. Sefler, H. T. Yura, A. A. Walston, N. I. Werner, and C. T. Mueller, “Wavelength Tracking Interferometer for DPSK Lasercom Links,” 2011 International Conference on Space Optical Systems and Applications, pp. 306–311 (Santa Monica, CA, 2011).
P. R. Rousseau et al., “TD-UTD Solutions for the Transient Radiation and Surface Fields of Pulsed Antennas Placed on PEC Smooth Convex Surfaces,” IEEE Transactions on Antennas and Propagation, Vol. 59, No. 5, pp. 1626–1637 (2011).
R. W. Russell, D. K. Lynch, et al., “Infrared Studies of Epsilon Aurigae in Eclipse,” Astronomical Journal, Vol. 142, No. 5, p. 174 (Nov. 2011).
S. C. Ruth, N. Sramek, M. M. Kwan, and R. P. Sena, “An Implementation of Technology Readiness Levels,” International SAMPE Technical Conference (2011).
J. R. Scarpulla, E. E. King, and J. V. Osborn, “Si SUB 3 N SUB 4 Extrinsic Defects and Capacitor Reliability,” IEEE International Reliability Physics Symposium Proceedings, pp. 2C.4.1–2C.4.10 (Monterey, CA, 2011).
G. Schubert, R. L. Walterscheid, et al., “Decadal Variations in a Venus General Circulation Model,” Icarus, Vol. 212, No. 1, pp. 42–65 (2011).
S. S. Shen et al., “Deepwater Horizon Oil Spill Monitoring Using Airborne Multispectral Infrared Imagery Algorithms and Technologies for Multispectral, Hyperspectral, and Ultraspectral Imagery,” Proceedings of SPIE—The International Society for Optical Engineering (2011).
Y. Sin, B. J. Foran, et al., “Traps and Defects in Pre- and Post-Stressed AlGaN-GaN High Electron Mobility Transistors,” Physica Status Solidi, Vol. 208, No. 7, pp. 1611–1613 (2011).
E. B. Song, B. H. Weiller, et al., “Continuity of Graphene on Polycrystalline Copper,” Nano Letters, Vol. 11, No. 1, pp. 251–256 (2011).
D. A. Taggart and R. Kumar, “Impact of Phase Noise on the Performance of the QPSK Modulated Signal,” 2011 IEEE Aerospace Conference (Big Sky, MT, 2011).
J. D. Train, J. A. Bannister, and C. S. Raghavendra, “Routing Fountains: Leveraging Wide-Area Broadcast to Improve Mobile Inter-Domain Routing,” MILCOM 2011 (2011).
D. M. Tratt, S. J. Young, D. K. Lynch, K. N. Buckland, P. D. Johnson, et al., “Remotely Sensed Ammonia Emission from Fumarolic Vents Associated with a Hydrothermally Active Fault in the Salton Sea Geothermal Field, California,” Journal of Geophysical Research. D. Atmospheres, Vol. 116, No. D21 (Nov. 2011).
R. E. Tuttle and J. A. Lollock, “Modal Test Data Adjustment for Interface Compliance,” Conference Proceedings of the Society for Experimental Mechanics Series, pp. 1029–1035 (Aug. 2011).
M. B. Van Dyke et al., “Spatial Variability Caused by Acoustic Wave Interference in Single-Drive Direct Field Acoustic Testing,” Journal of the IEST, Vol. 54, No. 2, pp. 54–74 (Oct. 2011).
R. L. Walterscheid et al., “Group Velocity and Energy Flux in the Thermosphere: Limits on the Validity of Group Velocity in a Viscous Atmosphere,” Journal of Geophysical Research, Vol. 116, No. D12, pp. D12101.1–D12101.12 (2011).
J. C. Wang, “Effects of Velocity Slip and Temperature Jump on the Boundary Layer Flow and Heat Transfer Over a Wedge,” 6th AIAA Theoretical Fluid Mechanics Conference (Honolulu, HI, 2011).
M. L. Wasz, “Coping with T30 Obsolescence in 2013,” 9th Annual International Energy Conversion Engineering Conference (San Diego, CA, 2011).
J. W. Welch, “Thermal Test Requirements for Spacecraft Propulsion Subsystem Units,” 42nd AIAA Thermophysics Conference (Honolulu, HI, 2011).
N. P. Wells, J. C. Camparo, B. Jaduszliwer, et al., “All-Optical Integrated Rubidium Atomic Clock,” 2011 Joint Conference of the IEEE International Frequency Control and the European Frequency and Time Forum, p. 5 (San Francisco, CA, June 2011).
C. Wang, L. Xu, and S. Lim, “Unequal Hierarchical Communications Modulation Method,” U.S. Patent No. 7,856,067, Dec. 2010.
Compressed data is typically encoded with a header, which contains more important information than other data segments. Current modulation approaches treat all data segments equally—but doing so requires more bandwidth than necessary. For optimal bandwidth utilization, it would be better to maximize the reliability of the header data and permit lower reliability of the subsequent segments. This can be accomplished using unequal coding for different segments. For example, an encoder encodes one data segment while another segment is left as uncoded. The coded and uncoded data are unequally modulated with a nonuniform 16-point constellation space, which can be optimized so that a minimum amount of transmitter power is needed.
G. Lui and K. Tsai, “Noncoherent Symbol Clock Recovery Subsystem,” U.S. Patent No. 7,864,887, Jan. 2011.
Digital communication systems transmit data by various carrier modulation techniques that typically involve synchronization of a transmitter clock and a receiver clock. This invention allows a receiver to recover the symbol epoch timing of a randomly modulated digital signal that may be noncoherently received through a noisy channel. A tap-delay line implementing a clock bank is used to sample the received signal at different times to generate time-staggered samples of the received signal, which are then fed through mean-magnitude generators to provide mean magnitudes that are insensitive to the phase offset of the carrier-signal. As the tap of the delay line that produces the largest mean magnitude is expected to be the closest to peak signal sampling timing than the other taps, its position in the delay line can be taken as an estimate of the timing offset between the transmitter and receiver clocks. This subsystem effectively provides rapid acquisition of the data symbol epoch of a signal received with arbitrary carrier phase. An advantage of the symbol clock recovery subsystem is its easy implementation and rapid acquisition performance even in noisy channels.
R. Douglas, “GPS M-Code Receiver Tracking System,” U.S. Patent No. 7,899,109, March 2011.
The GPS M-code autocorrelation function has seven modes or peaks, all indistinguishable with respect to conventional correlator tap arrangements. A problem with tracking the M-code signal is that it is not always clear which peak is being tracked. This results in either accurate but ambiguous tracking, or unambiguous but inaccurate tracking. This invention describes an M-code tracking system for use in a weak-lock, ultratight, or coherent navigation system. It determines multimodal code-phase errors by means of a coherent envelope, with the current mode aligned to a current code phase of a multimodal signal. The coherent envelope can encompass the multimodal correction function or a coherently received signal—for example, the autocorrelation function of a coherently received C/A-code signal. The system unambiguously and precisely determines the code-phase error of a multimodal spread-spectrum signal. By detecting a coherent envelope and unambiguously determining the mode, precise multimodal code-phase errors can be determined for improved tracking.
M. L. Polak, C. D. Nealy, J. P. Stafsudd, et al., “Infrared Gas Detection and Spectral Analysis Method,” U.S. Patent No. 7,956,761, June 2011.
Infrared spectroscopy is a rapid, sensitive, and chemically specific technique for chemical identification and quantification. When infrared spectroscopy is used continuously, threat and interferent chemicals could contaminate the infrared sensor. This invention is a data processing method for detection of threat chemicals contained in a user-specified list. The background model, which is key to this invention, is based on recent data history. Unless a threat chemical is detected in a given spectrum, that spectrum is used as part of the background model even if it contains signatures from interferent chemicals. As a result, detection of interferent chemicals is suppressed, but sensitivity towards the targeted threat chemicals is enhanced. When a threat chemical is detected, its concentration and detection confidence level is reported. The confidence level can then be used in an alarm decision process. The method can be operated continuously without human intervention, does not require independent calibration, and provides for sensitive detection with reduced false alarms. Its primary application is in infrared point detectors, which continuously protect a site.
B. B. Brady, “Noncircular Transient Fluid Fuel Injector Control Channels in Propellant Injector Combustion Systems,” U.S. Patent No. 7,958,719, June 2011.
Pulsed bipropellant thrusters are commonly used on spacecraft for in-space propulsion. Current propellant injector systems use conventional dribble channels and injectors producing mismatches in fuel and oxidizer delivery, contamination, and spikes in the combustion performance. Incomplete combustion could be one of the factors contributing to the low efficiency and high variability of pulsed thrusters. This invention provides for a fuel injector design that solves or reduces these disadvantages. It includes noncircular fuel and oxidizer injectors at the end of respective dribble channels to control the mixture of the propellants passing into a combustion chamber, thereby maintaining a desired mixture ratio and achieving a synchronized flow response. Synchronization of the propellant response times will prevent shifts in the mixture ratio, and lead to damping of pressure fluctuations and more stable combustion.
J. V. Osborn et al., “Surface Plasmon Polariton Actuated Transistors,” U.S. Patent No. 7,960,753, June 2011.
Conventional semiconductor interconnects suffer from increased dark current, limited frequency response, and relatively low bandwidths as compared to the optical regime. Semiconductor devices also suffer from polarization dependence limiting the plasmon waveguide. The invention is directed to a new class of semiconductors called plasmon polariton semiconductors, which receive and react to input excitation. These devices have a terminal that is electronically controlled by a surface plasmon waveguide, and a tip referred to as surface plasmon wire. The surface plasmon device solves the problem of slow interconnection by utilizing surface plasmon polariton wire structures as interconnects to the transistors comprising an integrated circuit. These devices can be applied to systems generally for large-scale chip interconnects. The small photo absorption volume of these devices reduces the dark current. Therefore, these devices can be used to make high-sensitivity infrared detectors.
A. D. Stapleton et al., “Electrically Tunable Plasmon Light Tunneling Junction,” U.S. Patent No. 7,961,995, June 2011.
The growth in demand for optical communication capabilities has created a renewed interest in nanoscale optical sources. This light source invention aims to fill the need for a compact high-speed optical emitter that can be modulated at speeds greater than 100 GHz. This emitter offers significant size, weight, and power advantages over the current field of semiconductor solid-state light emitters. Light emission is produced through the inelastic tunneling of electrons through a thin insulator that is sandwiched between two metal electrodes. As electrons tunnel through a thin insulator, they emit light through a scattering process. Light is coupled out of the small area tunnel junction through a gradual tapered contact. This tapered transition between the several-nanometer-thick tunnel junction and micron-scale output waveguide makes this invention more efficient than previous incarnations. Without the taper, light emitted in the tunnel junction would be absorbed in a few tens of nanometers by the surrounding metal electrode structure. The entire structure can be constructed with materials that are compatible with standard CMOS fabrication processes. Therefore, this device can be integrated within silicon microelectronic devices without requiring the complex and costly hybrid integration of other semiconductor materials. Applications include chip-to-chip and board-to-board level data communication at data rates that would otherwise be impossible with conventional electrical interconnects.
K. Siri, “Converter Channelized Uniform Power Distribution System,” U.S. Patent No. 7,964,991, June 2011.
Multiple dc-dc converters can be connected to form a serial-input connected parallel-output (SIPO) converter power channel. Many SIPO converter power channels can be parallel-connected across the power system output that shares a common load, allowing for an expanding number of converters within the same power system. This provides sufficient power to the load. Without proper control for equal sharing among the output currents of paralleled power channels, this channelized series-connected converter architecture alone introduces conflicts in output voltage regulation control. This leads to nonuniform power flows among channels and possible unequal utilization, consequently degrading system reliability. The invention is characterized by a channelized power system having a plurality of channels. Each channel contains power converters and respective channel controllers for controlling the power provided by the channels. The controllers are interconnected by a shared bus voltage signal and a shared bus current signal, so that the paralleled channels and converters within each channel are respectively controlled to have equal power sharing. The two shared-bus signals stabilize interactions among interconnected channels and converters within each channel, significantly reducing imbalances in power flow. Conflicts in the system output voltage regulation are also eliminated while achieving very stiff output voltage. Fault tolerance is also included among series-connected converters that actively sustain equal input voltages among remaining no-fault converters, even if one or more converters is down. The channelized power system can be used in satellite power systems having different voltage requirements and expansive battery charges.
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