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Advanced Wireless Communications Technologies For Low Power, Reconfigurable Small Satellite Radios, Michael Tompkins, Matthew Warner, Todd Mosher
Advanced Wireless Communications Technologies For Low Power, Reconfigurable Small Satellite Radios, Michael Tompkins, Matthew Warner, Todd Mosher
Small Satellite Conference
Advances in smart antennas, coding theory, power amplifiers, low-power electronics, and softwaredefined radios have dramatically impacted terrestrial communications. The improvements achieved in frequency reuse, interference mitigation, handset battery life, error performance, and hardware reconfigurability can be transitioned to small satellite communications systems. The stringent power budgets, limited antenna apertures, and rapid development times associated with small satellites make these technologies particularly important. Also, the shorter lifetimes and higher levels of acceptable risk typical of small satellite missions make the utilization of advanced commercial-off-the-shelf (COTS) components feasible. This paper describes an effort underway to study flexible radio architectures that can rapidly …
Rapid De-Orbit Of Leo Space Vehicles Using Towed Rigidizable Inflatable Structure (Tris) Technology: Concept And Feasibility Assessment, Dave Beckett, Bryce Carpenter, Costas Cassapakis
Rapid De-Orbit Of Leo Space Vehicles Using Towed Rigidizable Inflatable Structure (Tris) Technology: Concept And Feasibility Assessment, Dave Beckett, Bryce Carpenter, Costas Cassapakis
Small Satellite Conference
The amount of debris in Earth orbit is increasing at an extraordinary rate and presents a growing hazard to orbital operations. Most of the debris in low earth orbit (LEO) is man made and consists of inactive spacecraft and/or launch vehicle upper stages. International treaties and US Government requirements dictate that all space vehicles (SV’s) must be de-orbited or moved to a higher orbit within a limited time (within 25 years of EOL – NASA/FCC Requirement). A separate guideline requires that medium to large spacecraft be disposed of via a controlled deorbit into a remote portion of the Pacific Ocean. …
An Integrated Vision-Based System For Spacecraft Attitude And Topology Determination For Formation Flight Missions , Aaron Rogers, Kalle Anderson, Anna Mracek, Ray Zenick, Jefferson Grau, Cheryl Gramling
An Integrated Vision-Based System For Spacecraft Attitude And Topology Determination For Formation Flight Missions , Aaron Rogers, Kalle Anderson, Anna Mracek, Ray Zenick, Jefferson Grau, Cheryl Gramling
Small Satellite Conference
With the space industry’s increasing focus upon multi-spacecraft formation flight missions, the ability to precisely determine system topology and the orientation of member spacecraft relative to both inertial space and each other is becoming a critical design requirement. Topology determination in satellite systems has traditionally made use of GPS or ground uplink position data for low Earth orbits, or, alternatively, inter-satellite ranging between all formation pairs. While these techniques work, they are not ideal for extension to interplanetary missions or to large fleets of decentralized, mixed-function spacecraft. The Vision-Based Attitude and Formation Determination System (VBAFDS) represents a novel solution to …
Application Of Emerging Structural Energy Storage Technology To Small Satellite Systems , Philip Lyman, John Olson, Timothy Feaver
Application Of Emerging Structural Energy Storage Technology To Small Satellite Systems , Philip Lyman, John Olson, Timothy Feaver
Small Satellite Conference
Boundless Corporation and Composite Optics Inc. (ATK/COI), with funding from NASA and the Missile Defense Agency, are developing unique multifunctional structure technology that incorporates energy storage devices as load bearing elements in structural panel assemblies. The technology offers opportunities to save mass and volume that are especially attractive for small satellites. This paper introduces Boundless’ approach to structural energy storage and describes the development status of both structural lithium-ion batteries and structural ultracapacitors. Both devices employ carbon composites that combine energy storage and structural functionality at the level of the electrode. NASA’s proposed Magnetospheric Constellation (MAGCON) mission served as a …
Disruptive Space Technology, Jim Benson
Disruptive Space Technology, Jim Benson
Small Satellite Conference
In 1997 "The Innovator’s Dilemma" by Clayton M. Christensen became a popular book in the small satellite and launch vehicle communities. But like the weather, every one talks about “Disruptive Technology” but few do anything about it. In the ‘70s and ‘80s, people were looking for “Paradigm Shifts,” and since the resurrection of Donald Rumsfeld, a recent watchword has been “Transformational Technology.” But today’s buzzword is now “Responsive Space Systems.”
University-Class Satellites: From Marginal Utility To 'Disruptive' Research Platforms, Michael Swartwout
University-Class Satellites: From Marginal Utility To 'Disruptive' Research Platforms, Michael Swartwout
Small Satellite Conference
The last ten years have seen a tremendous increase in the number of student-built spacecraft projects; however, the main outcome of these programs has been student training and, on some occasions, extremely low-cost space access for the university science community. Because of constrained resources and an inherently-constrained development team (students), universities have not been in a position to develop 'disruptive' space technologies; in order to secure launches, they are forced to build low-capability, high-margin systems using established design practices. However, universities have one inherent advantage in developing 'disruptive' space systems: the freedom to fail. Experimental failure is a basic element …
Real-Time Mission Planning For Responsive Space Lift, Brian Horais, Joe Guerci
Real-Time Mission Planning For Responsive Space Lift, Brian Horais, Joe Guerci
Small Satellite Conference
The 2002 Mission Need Statement for Operationally Responsive Spacelift (ORS MNS) “establishes the requirement for responsive, on-demand access to, through and from space. It also requires on-demand, flexible, and cost effective operations.” [RDT&E R-2 Exhibit, PE 0604855F]. A number of activities have been initiated to respond to this mission need, such as DARPA’s RASCAL and FALCON programs, but their primary emphasis is on the launch vehicle. Responsive Space Lift is a function of the launch vehicle, the payload and the process support. Launch vehicles must be capable of inserting payloads into the desired orbits within hours, payloads must be checked …
A Metrics To Support The Design Of Small Satellite Based High Resolution Mapping Systems , Rainer Sandau
A Metrics To Support The Design Of Small Satellite Based High Resolution Mapping Systems , Rainer Sandau
Small Satellite Conference
High resolution mapping systems follow the trend to smaller ground sample distances (GSD) making use of the best technology available at the given time. From the 80 m GSD of ERTS in 1972, the GSD now approached 1 m and even less. Mass and power consumption of spacecrafts and imaging instruments follow similar trends in conjunction with the immense improvements in very divers fields of technology. The paper tries to give a metrics and analytical method to assess how far can we go with decreasing instrument size and decreasing the GSD at the same time and what features the spacecraft …
Small Satellite Standards Development, Jeff Ganley
Small Satellite Standards Development, Jeff Ganley
Small Satellite Conference
The Air Force Research Laboratory, in conjunction with numerous government, academic, professional organizations and industry, is initiating the development of a set of small satellite standards. It is envisioned that these standards will encompass standard launch vehicle mechanical and electrical interfaces, as well as inter-satellite mechanical, electrical and software interfaces. The procedure that is being followed in the standards development process is to engage the stakeholders in the small satellite community in a dialogue to determine which, if any, of the above standards can be implemented in the near term. Those standards would then be included in relevant future solicitations …
Evaluating The Present And Potential Future Impact Of Small Satellites, Andrew Lewin
Evaluating The Present And Potential Future Impact Of Small Satellites, Andrew Lewin
Small Satellite Conference
The theme of the 18th Annual AIAA/USU Conference on Small Satellites questions whether small satellites are a complimentary or a disruptive technology. This paper addresses this question by performing an analysis of the role small satellites play in the space market. The market is segmented into three primary components, military space, civil space, and commercial space. Analysis focuses on the U.S. space market. The analysis shows that while small satellites perform some valuable missions, they represent only a small part of the overall space market. Furthermore, although there are some upcoming opportunities for small satellites, they do not appear to …
The Deployable Structures Experiment: Design Of A Low-Cost, Responsive R&D Space Mission , Dan Cohen, Scott Greeley, Shane Kemper, Jim King, Larry Davis, Gregory Spanjers, James Winter, Aaron Adler
The Deployable Structures Experiment: Design Of A Low-Cost, Responsive R&D Space Mission , Dan Cohen, Scott Greeley, Shane Kemper, Jim King, Larry Davis, Gregory Spanjers, James Winter, Aaron Adler
Small Satellite Conference
The Air Force Research Laboratory (AFRL) Space Vehicles Directorate has developed the Deployable Structures Experiment (DSX) to research technologies needed for large space structures and apertures, high-power generation, and survivability in the high radiation environment of a medium earth orbit (MEO). DSX is designed to perform five basic research experiments that coupled together provides DoD with the technological understanding needed to achieve transformational capability in space surveillance, microsats with large aperture and power, active space capability protection from enhanced radiation belts, and radiation-survivability design criteria for satellite systems planned for the highly desirable medium Earth orbit (MEO) regime. The five …
Roadrunner, A High-Performance Responsive Space Mission, Terrance Yee
Roadrunner, A High-Performance Responsive Space Mission, Terrance Yee
Small Satellite Conference
The Roadrunner mission is being conducted by the Air Force Research Laboratory (AFRL) to demonstrate techniques and methodologies to dramatically shorten the development time required for small satellites. The Roadrunner program will demonstrate a 14-month development time from inception to launch readiness, a one-week time from call up to on-orbit readiness, and a 24-hour autonomous on-orbit commissioning. Roadrunner will accomplish these impressive schedule milestones while fielding a suite of experiments centered around a new optical imager capable of sub 1 meter resolution and nearly a dozen complimentary payloads. To accomplish this mission, the Roadrunner spacecraft is built on a bus …
Defense And Environmental Objectives For The Russian American Observational Satellites (Ramos) Program , T. Humpherys, V. Privalsky, V. Sinelshchikov, V. Abramov, V. Misnik, A.T. Stair, I. Schiller
Defense And Environmental Objectives For The Russian American Observational Satellites (Ramos) Program , T. Humpherys, V. Privalsky, V. Sinelshchikov, V. Abramov, V. Misnik, A.T. Stair, I. Schiller
Small Satellite Conference
The Russian American Observational Satellites (RAMOS) program represents a new direction for cooperative space-based research and development between the Russian Federation and the United States. The objective of the RAMOS project is to engage in a joint program employing simultaneous stereo-optical techniques from two co-orbiting satellites to address global defense and environmental issues. The satellites are equipped with American- and Russian-made passive electro-optical sensors operating over a spectral range from infrared (IR) to ultraviolet (UV) which can conduct near-simultaneous stereo-optical radiometric, spectrometric, and polarimetric measurements. The defense objectives will demonstrate the capability for improved target observation and reduced “false alarm” …
Keynote Address, Dr. Tony Tether
Utah State University, Auroral Research, And The Cold War, Paul Concidine
Utah State University, Auroral Research, And The Cold War, Paul Concidine
Utah Space Grant Consortium
On November 19, 1976, a Talos-Castor rocket left the Poker Flat Research Range near Fairbanks, Alaska. Prepared by a team of engineers from Utah State University, the primary scientific instruments on board were two high power electron accelerators designed to shoot powerful beams of electrons into the atmosphere, thus creating artificial aurora. Though one of the accelerators experienced a short circuit, the other produced the desired electron beam up to and as the rocket reached its apogee at 265 kilometers, and then throughout its descent to approximately 84 kilometers.1 This particular launch, however, was merely a test of the electron …
Mesospheric Temperature Climatology And Comparisons Above The Rocky Mountains, Joshua P. Herron
Mesospheric Temperature Climatology And Comparisons Above The Rocky Mountains, Joshua P. Herron
Utah Space Grant Consortium
A Rayleigh-scatter lidar has been operated by the Center for Atmospheric and Space Sciences (CASS) at Utah State University (USU) since 1993. The lidar measures atmospheric temperatures between 45 and 90 km which are important for understanding the physics and chemistry of the middle atmosphere. The temperature profiles were used to create a multi-year temperature climatology. This climatology was used for comparisons with the temperature climatology from the Purple Crow Lidar at the University of Western Ontario, and nightly temperature profiles from the SABER instrument on board the TIMED satellite.
Saber Data Processing, Ricky L. Fielding
Saber Data Processing, Ricky L. Fielding
Utah Space Grant Consortium
SABER is an infrared multi-spectral radiometer aboard the TIMED satellite. It measures radiatively active species in the atmospheric region from 60 km to 130 km altitude. We are particularly interested in the 2.06 μm and 1.67 μm bands as an indication of the Hydroxyl (OH) concentration in the atmosphere. Here, we detail visualization work along with early results from the SABER OH radiometer channels.
Recent Results From The Usu Plasma Impedance Probe For The Nasa E-Winds Sounding Rocket Campaign, Chad G. Carlson
Recent Results From The Usu Plasma Impedance Probe For The Nasa E-Winds Sounding Rocket Campaign, Chad G. Carlson
Utah Space Grant Consortium
The new plasma impedance probe built by Utah State University was °own on July 1, 2003 as part of a NASA sounding rocket cam- paign to investigate midlatitude plasma layers and neutral winds. The instrument provided measure- ments of absolute and relative electron densities for the mission. The instrumentation technique is brie°y introduced, along with the plasma param- eters that the technique is capable of measuring. Relative electron densities from the DC Langmuir probe for the mission are presented along with a comparison of the relative density data to the ab- solute density provided by the plasma frequency probe.
Scattering Computations From Canonical Geometries And Their Accuracy, Clayton Davis
Scattering Computations From Canonical Geometries And Their Accuracy, Clayton Davis
Utah Space Grant Consortium
An overview of the computation of electromagnetic scattering is presented. Issues of solution convergence and future work in error analysis is also discussed.
Motion Compensation Of Interferometric Synthetic Aperture Radar, David P. Duncan
Motion Compensation Of Interferometric Synthetic Aperture Radar, David P. Duncan
Utah Space Grant Consortium
Synthetic aperture radar (SAR) is a digital signal processing technique which enhances the azimuth resolution of a radar image using the target Doppler history created by the motion of the radar platform. If the platform deviates from a constant velocity, straight-line path then image quality is lost and image details become unfocused. Motion compensation (MOCO) is a technique in which the position and attitude of the platform is recorded or estimated and then used to correct the scene’s Doppler history as if a straight-line, constant velocity path had been taken. Brigham Young University’s interferometric synthetic aperture radar (YINSAR) was flown …
An Infrared Approach To Thin-Layer Based Biosensors, Ignacio J. Garcia, Nicole Branan, Rola Altoos, Todd A. Wells
An Infrared Approach To Thin-Layer Based Biosensors, Ignacio J. Garcia, Nicole Branan, Rola Altoos, Todd A. Wells
Utah Space Grant Consortium
Biosensors exploit the theoretical and instrumental approaches of analytical chemistry and the unique properties of biological molecules. They utilize the intermolecular interactions and specificity found in systems such as hormone-receptor, antigenantibody, pathogen-host and substrate-enzyme. Manipulation of the structural and energetic factors that guide formation of these macromolecular complexes may provide a rational basis for the development of new sensor technology. To this end we have investigated myoglobin thin films for their ability to bind ligands. FTIR spectroscopy has been chosen as the transduction methods and has been shown to discriminate between several analytes.
Siftir: Spectro-Polarimetric Imaging Fourier Transform Spectrometer For The Infrared, Colby Jurgenson, Robert Stencel
Siftir: Spectro-Polarimetric Imaging Fourier Transform Spectrometer For The Infrared, Colby Jurgenson, Robert Stencel
Utah Space Grant Consortium
Observations of evolved stars in the infrared are well suited for studies of dusty environments, providing a wealth of absorption and emission bands with which to diagnose grain characteristics. We are currently developing an instrument that will employ a Fourier transform spectrometer in conjunction with TNTCAM2 (Klebe et al. 1998), an imaging polarimeter. The FTS component will enhance TNTCAM2, giving the instrument a maximum resolution of 2000 at 10 11m. The FTS is capable of operating between 2-15 11m, but polarimetry for the instrument is limited to the 8-15 11m region due to waveplate/wiregrid characteristics. SIFTIR, the Spectro-polarimetric Imaging Fourier …
Choosing A Starting Configuration For Particle Swarm Optimization, Mark Richards, Dan Ventura
Choosing A Starting Configuration For Particle Swarm Optimization, Mark Richards, Dan Ventura
Utah Space Grant Consortium
The performance of Particle Swarm Optimization can be improved by strategically selecting the starting positions of the particles. This work suggests the use of generators from centroidal Voronoi tessellations as the starting points for the swarm. The performance of swarms initialized with this method is compared with the standard PSO algorithm on several standard test functions. Results suggest that CVT initialization improves PSO performance in high-dimensional spaces.
Improving Electromagnetic Bias Estimates, Floyd W. Millett, Karl F. Warnick
Improving Electromagnetic Bias Estimates, Floyd W. Millett, Karl F. Warnick
Utah Space Grant Consortium
The derivation of an electromagnetic (EM) bias model that includes the physical optics scattering models and the non-Gaussian long wave surface statistics is presented. The final formulation of the model is expressed as a function of hydrodynamic modulation, surface skewness, and tilt modulation. Through the modulation transfer function, the hydrodynamic modulation coefficient is shown to be equivalent to the long wave RMS slope multiplied by a function of the short wave spectrum. With this result the normalized EM bias reduces to a function of long wave surface parameters with coefficients determined by properties of the short ocean waves. EM bias …