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Full-Text Articles in Aerospace Engineering

Single Wavelength Lidar Retrieval Algorithm Of Particulate Matter Concentration Using Celis (Compact Eyesafe Lidar System), A 1.5 Μm Elastic Lidar System, Alan W. Bird, Kori D. Moore, Michael Wojcik, Robert Lemon May 2015

Single Wavelength Lidar Retrieval Algorithm Of Particulate Matter Concentration Using Celis (Compact Eyesafe Lidar System), A 1.5 Μm Elastic Lidar System, Alan W. Bird, Kori D. Moore, Michael Wojcik, Robert Lemon

Space Dynamics Laboratory Publications

CELiS (Compact Eyesafe Lidar System) is an elastic backscatter light detection and ranging (lidar) system developed for monitoring air quality environmental compliance regarding particulate matter (PMk) generated from off-road use of wheeled and tracked vehicles as part of the SERDP (Strategic Environmental Research and Development Program) Measurement and Modeling of Fugitive Dust Emission from Off-Road DoD Activities program.

CELiS is small, lightweight and easily transportable for quick setup and measurement of PMk concentration and emissions. CELiS operates in a biaxial configuration at the 1.5μm eyesafe wavelength with a working range of better than 6 km and range …


Gradient Projection For Interrupted Sar Using The Polar Format Algorithm, Ross Deming, Chad Knight, Jake Gunther May 2015

Gradient Projection For Interrupted Sar Using The Polar Format Algorithm, Ross Deming, Chad Knight, Jake Gunther

Space Dynamics Laboratory Publications

We present an efficient and computationally simple approach for synthetic aperture radar (SAR) imaging in cases when the radar data have gaps, due to missing pulses and/or notches in the frequency band. Our method is a simple variation of gradient projection, in which the search path in each iteration is obtained by projecting the negative-gradient of the L1 norm onto a hyper-plane defining solutions which are consistent with the data. The computations are not complicated since the L1 gradient is simply equal to the sign() of the pixels in the image. Computational efficiency is obtained by incorporating the polar format …


Demonstration Of Co2 Ch4 And Pm Detection Using Differentia Absorption Lidar (Dial) Development Of Advanced Air Monitoring Technology For Alberta, Michael Wojcik, Blake Crowther, Robert Lemon, Prasad Valupadas, Long Fu, Bonnie Leung, Zhang Yang, Quamrul Huda, Allan Chambers May 2015

Demonstration Of Co2 Ch4 And Pm Detection Using Differentia Absorption Lidar (Dial) Development Of Advanced Air Monitoring Technology For Alberta, Michael Wojcik, Blake Crowther, Robert Lemon, Prasad Valupadas, Long Fu, Bonnie Leung, Zhang Yang, Quamrul Huda, Allan Chambers

Space Dynamics Laboratory Publications

Rapid expansion of the oil and gas industry in Alberta, including the oil sands, has challenged the Alberta Government to keep pace in its efforts to monitor and mitigate the environmental impacts of development. The limitations of current monitoring systems has pushed the provincial government to seek out advanced sensing technologies such as satellite imagery and laser based sensors. The Space Dynamics Laboratory (SDL) of Utah State University, in cooperation with Alberta Environmental Monitoring, Evaluation and Reporting Agency (AEMERA), has developed North America’s first mobile differential absorption lidar (DIAL) system designed specifically for emissions measurement. This instrument is housed inside …


Clutter Suppression Interferometry System Design And Processing, Chad Knight, Ross Deming, Jake Gunther May 2015

Clutter Suppression Interferometry System Design And Processing, Chad Knight, Ross Deming, Jake Gunther

Space Dynamics Laboratory Publications

Clutter suppression interferometry (CSI) has received extensive attention due to its multi-modal capability to detect slow-moving targets, and concurrently form high-resolution synthetic aperture radar (SAR) images from the same data. The ability to continuously augment SAR images with geo-located ground moving target indicators (GMTI) provides valuable real-time situational awareness that is important for many applications. CSI can be accomplished with minimal hardware and processing resources. This makes CSI a natural candidate for applications where size, weight and power (SWaP) are constrained, such as unmanned aerial vehicles (UAVs) and small satellites applications.

This paper will discuss the theory for optimal CSI …


A Radio Frequency Beacon Receiver For Detection Of Ionospheric Scintillation, Tim Neilsen, Don Thompson, Steve Higley, Todd Parris, Jake Gunther Apr 2015

A Radio Frequency Beacon Receiver For Detection Of Ionospheric Scintillation, Tim Neilsen, Don Thompson, Steve Higley, Todd Parris, Jake Gunther

Space Dynamics Laboratory Publications

Radio Frequency Beacon Receiver

  • What is RFBR?
  • A low-cost, ground-based beacon receiver
  • Producing ionospheric parameters:
  • Total Electron Content (TEC) 
  • Amplitude scintillation (S4)
  • Phase scintillation (σφ)
  • Using COTS RF hardware and Software Defined Radios (SDRs) 
  • Advanced algorithms and software


Particulate Matter Emission Estimates From Agricultural Spring Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randal S. Martin, Christian C. Marchant, Derek S. Jones, William J. Bradford, Gail E. Bingham, Richard L. Pfeiffer, John H. Prueger, Jerry L. Hatfield Apr 2015

Particulate Matter Emission Estimates From Agricultural Spring Tillage Operations Using Lidar And Inverse Modeling, Kori D. Moore, Michael D. Wojcik, Randal S. Martin, Christian C. Marchant, Derek S. Jones, William J. Bradford, Gail E. Bingham, Richard L. Pfeiffer, John H. Prueger, Jerry L. Hatfield

Space Dynamics Laboratory Publications

Particulate matter (PM) emissions from a typical spring agricultural tillage sequence and a strip-till conservation tillage sequence in California’s San Joaquin Valley were estimated to calculate the emissions control efficiency (η) of the strip-till conservation management practice (CMP). Filter-based PM samplers, PM-calibrated optical particle counters (OPCs), and a PM-calibrated light detection and ranging (lidar) system were used to monitored upwind and downwind PM concentrations. Emission rates were estimated through inverse modeling coupled with the filter and OPC measurements and through applying a mass balance to the PM concentrations derived from lidar data. Sampling irregularities and errors prevented the estimation of …


A Low-Cost, Software Defined, Ground-Based Radio Frequency Beacon Receiver (Rfbr) For Measuring Ionosphere Tec And Amplitude And Phase Scintillation, Jacob Gunther, Chad Fish, Charles Swenson, Tim Neilsen, Brent Haslem, Bryan Hansen, Kelby Davis, Steve Higley, Todd Parris, Don Thompson, Charles Rino, Keith Groves Jan 2015

A Low-Cost, Software Defined, Ground-Based Radio Frequency Beacon Receiver (Rfbr) For Measuring Ionosphere Tec And Amplitude And Phase Scintillation, Jacob Gunther, Chad Fish, Charles Swenson, Tim Neilsen, Brent Haslem, Bryan Hansen, Kelby Davis, Steve Higley, Todd Parris, Don Thompson, Charles Rino, Keith Groves

Space Dynamics Laboratory Publications

By monitoring the effects of the ionosphere on multiple space originating radio frequency (RF) beacons, characterizing parameters can be derived which can then be ingested into global assimilative models to improve ionospheric specification and to estimate ionosphere-induced degradation of communication and navigation signals across the electromagnetic spectrum. This paper describes the requirements, design and construction of a ground-based beacon receiver for measuring total electron concentration and amplitude and phase scintillation of the ionosphere. The design achieves very low cost by using the latest in commercial RF and software defined radio technology. The receiver can simultaneously observe three tones spanning ultra-high …


Characterizing Noise Trends Of The Cross-Track Infrared Sounder (Cris), Bryce Walker, Mark Esplin, Ben Esplin, Deron Scott Jan 2015

Characterizing Noise Trends Of The Cross-Track Infrared Sounder (Cris), Bryce Walker, Mark Esplin, Ben Esplin, Deron Scott

Space Dynamics Laboratory Publications

Outline

• CrIS Summary

• Noise characterization process

• Noise trending results

• Recent Changes

• Conclusions


Dcgs: Image Processing, Screening, & Product Distribution Solution, Space Dynamics Laboratory Jan 2015

Dcgs: Image Processing, Screening, & Product Distribution Solution, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SCALABLE, CROSS-PLATFORM SOLUTION FOR NEAR REAL-TIME IMAGE PROCESSING, SCREENING, & PRODUCT DISTRIBUTION

SDL provides the Distributed Common Ground System (DCGS) community with a powerful image processing, screening, and product distribution solution by combining a ground station with the VANTAGE™ tactical intelligence software suite and the Sky Lynx data link interface hardware. This system's cost-effectiveness is achieved through the use of flexible and robust hardware configurations that enable the customer to scale the system to their DCGS program needs.


Microgravity Testing Of A Phase Change Reference On The International Space Station, T. Shane Topham, Gail E. Bingham, Harri Latvakoski, Igor Podolski, Vladimir S. Sychev, Andre Burdakin Jan 2015

Microgravity Testing Of A Phase Change Reference On The International Space Station, T. Shane Topham, Gail E. Bingham, Harri Latvakoski, Igor Podolski, Vladimir S. Sychev, Andre Burdakin

Space Dynamics Laboratory Publications

Orbital sensors to monitor global climate change during the next decade require low drift rates for onboard thermometry, which is currently unattainable without on-orbit recalibration. Phase change materials (PCM), such as those that make up the ITS-90 standard, are seen as the most reliable references on the ground and could be good candidates for orbital recalibration. Space Dynamics Lab (SDL) has been developing miniaturized phase change references capable of deployment on an orbital blackbody for nearly a decade. To determine if and how microgravity will affect the phase transitions, SDL conducted experiments with ITS-90 standard material (gallium, Ga) on the …


Generating Technical Data For Strategic Source Of Repair (Ssor) & Source Of Repair Assignment Process (Sorap), Brent A. Carlsen Dec 2014

Generating Technical Data For Strategic Source Of Repair (Ssor) & Source Of Repair Assignment Process (Sorap), Brent A. Carlsen

Space Dynamics Laboratory Publications

SDL Presentation on SSOR and SORAP Technical Data


Potential Airborne Optical Contributions To The European Phased Adaptive Approach (Epaa) For Missile Defense, Garry Schnelzer, Sean Collins, Scott Hansen, Joe Kristl Nov 2014

Potential Airborne Optical Contributions To The European Phased Adaptive Approach (Epaa) For Missile Defense, Garry Schnelzer, Sean Collins, Scott Hansen, Joe Kristl

Space Dynamics Laboratory Publications

Outline

  • European Phased Adaptive Approach (EPAA)
  • Airborne Optical Sensor’s Contribution and Coverage
  • Notional Airborne Optical Sensor and Performance
  • Recommendations


Ammonia Measurements And Emissions Estimates From A California, Usa Dairy Using Both Point And Remote Sensors, Kori Moore, Emyrei Young, Cassi Gurell, Michael Wojcik, Randall Martin, Gail Bingham, Richard Pfeiffer, John Prueger, Jerry Hatfield Nov 2014

Ammonia Measurements And Emissions Estimates From A California, Usa Dairy Using Both Point And Remote Sensors, Kori Moore, Emyrei Young, Cassi Gurell, Michael Wojcik, Randall Martin, Gail Bingham, Richard Pfeiffer, John Prueger, Jerry Hatfield

Space Dynamics Laboratory Publications

Background

  • Question: How much does a US open lot dairy contribute to local and regional PM loadings?
    • Primary PM: dust, combustion sources
    • Secondary PM: NH3, NOx, SOx, VOCs
    • Climate, housing, manure management, and other confounding factors
  • Emissions measurements are required to help answer this question
  • Study Objective:
    • Characterize PM2.5, PM10, TSP, and gaseous NH3concentrations, fluxes, and emissions from a commercial dairy using both point and remote sensing techniques
    • Results reported in:
      • Marchant et al. 2011. Estimation of dairy particulate matter emissions from a California dairy …Trans. ASABE …


Feasibility Considerations For A Long-Range Passive Vibrometer, Alan Marchant, Chad Fish, Jie Yao, Phillip Cunio, Wellesley Pereira Sep 2014

Feasibility Considerations For A Long-Range Passive Vibrometer, Alan Marchant, Chad Fish, Jie Yao, Phillip Cunio, Wellesley Pereira

Space Dynamics Laboratory Publications

Hypertemporal imaging enables the long-range characterization of vibration modes and amplitudes of a passively illuminated structure. The vibration signature arises from modulation of the bidirectional reflection distribution function (BRDF) as the surface normal oscillates with respect to a fixed, directional source. This paper considers the instrument design characteristics and environmental factors that limit passive vibrometer performance including BRDF angle sensitivity, receiver spatial resolution, interference from atmospheric scintillation, and intrinsic detector performance. It also identifies a sensor architecture that is capable of characterizing surface vibration at amplitudes below 1 mrad rms and discuss detector technology that can further improve long-range vibrometer …


Our Decade In Space Plug-And-Play Avionics (Spa), James Lyke, Quinn Young, Jacob Christensen, David Anderson Aug 2014

Our Decade In Space Plug-And-Play Avionics (Spa), James Lyke, Quinn Young, Jacob Christensen, David Anderson

Space Dynamics Laboratory Publications

Outline

  • History / Background
  • Overview of Plug-and-Play Technology
  • Current Status
  • Road Ahead


Precision Tracking Space System (Ptss) Infrared Sensor Thermal Testing And Model Correlation, Matt Felt, Brian Thompson, Lorin Zollinger, Mike Marley, Ed Hawkins, Patrick Stadter Aug 2014

Precision Tracking Space System (Ptss) Infrared Sensor Thermal Testing And Model Correlation, Matt Felt, Brian Thompson, Lorin Zollinger, Mike Marley, Ed Hawkins, Patrick Stadter

Space Dynamics Laboratory Publications

The Precision Tracking Space System (PTSS) was a constellation of infrared (IR) sensors planned by the US Missile Defense Agency (MDA) to observe and track ballistic missile objects in flight. The PTSS program funded testing to characterize the parasitic heat loads expected on the actively-cooled multi-band IR sensor assembly, a subassembly within the optical telescope, thereby reducing uncertainty in the cooler heat lift requirements and system power budget. A detailed flight-like thermal analog of the sensor assembly, including designed conductances, surface treatments, and multi-layer insulation, was tested in a fixture that simulated its flight interfaces with a controllable interface temperature. …


Application Of A Modified Backwards Lagrangian Stochastic Model To Estimate Particulate Matter Emissions From A Dairy, Kori Moore, Michael Wojcik, Randy Martin, Richard Pfeiffer, John Prueger, Jerry Hatfield Jul 2014

Application Of A Modified Backwards Lagrangian Stochastic Model To Estimate Particulate Matter Emissions From A Dairy, Kori Moore, Michael Wojcik, Randy Martin, Richard Pfeiffer, John Prueger, Jerry Hatfield

Space Dynamics Laboratory Publications

Background

  • SDL, USU, and ARS have assembled sensors to measure PM and NH3 concentrations around area sources
    • Point and remote sensors, including a PM calibrated scanning lidar
  • Emissions estimated using concentration measurements
    • Mass balance (lidar only)
    • Inverse modeling


Space Layer Experiment (Slx) Sensor Calibration, Scott Hansen, Brian Thompson, Lorin Zollinger, Dean Wada, Ed Hawkins, Brian Kantsiper Jul 2014

Space Layer Experiment (Slx) Sensor Calibration, Scott Hansen, Brian Thompson, Lorin Zollinger, Dean Wada, Ed Hawkins, Brian Kantsiper

Space Dynamics Laboratory Publications

The Space Layer Experiment (SLX) is a sensor planned by the US Missile Defense Agency (MDA) to test technology to observe and track objects in space. Subject to SLX program and funding restraints, a detailed and thorough ground calibration is planned to support observation and tracking goals, with continuing calibration experiments planned after launch. This presentation provides an overview of the SLX ground calibration that will use existing SDL calibration equipment and expertise with allowances made for SLX sensor design and program schedule. Preliminary plans for on-orbit calibration will also be presented with the goal of receiving expert feedback to …


Side-Stepping The Politics: Cooperative Programs, James Marshall, Garry Schnelzer Jun 2014

Side-Stepping The Politics: Cooperative Programs, James Marshall, Garry Schnelzer

Space Dynamics Laboratory Publications

SDL Presentation on International Cooperative Programs


Model-Based 3d Sar Reconstruction, Chad Knight, Jake Gunther, Todd Moon Jun 2014

Model-Based 3d Sar Reconstruction, Chad Knight, Jake Gunther, Todd Moon

Space Dynamics Laboratory Publications

Three dimensional scene reconstruction with synthetic aperture radar (SAR) is desirable for target recognition and improved scene interpretability. The vertical aperture, which is critical to reconstruct 3D SAR scenes, is almost always sparsely sampled due to practical limitations, which creates an underdetermined problem. This papers explores 3D scene reconstruction using a convex model-based approach. The approach developed is demonstrated on 3D scenes, but can be extended to SAR reconstruction of sparsely sampled signals in the spatial and, or, frequency domains. The model-based approach enables knowledge-aided image formation (KAIF) by incorporating spatial, aspect, and sparsity magnitude terms into the image reconstruction. …


Making Every Gram Count - Big Measurements From Tiny Platforms, C. S. Fish, C. M. Swenson, S. Bailey, R. Bevilacqua, T. Neilsen, A. Marchant, C. Frazier, E. Stromberg, C. Weston, M. Jeppesen, J. Sojka May 2014

Making Every Gram Count - Big Measurements From Tiny Platforms, C. S. Fish, C. M. Swenson, S. Bailey, R. Bevilacqua, T. Neilsen, A. Marchant, C. Frazier, E. Stromberg, C. Weston, M. Jeppesen, J. Sojka

Space Dynamics Laboratory Publications

Significant advances in Earth, solar, and space physics over the next decades will originate from new, system-level observational techniques. The most promising technique to still be fully developed and exploited requires conducting multi-point or distributed constellation-based observations. This system-level observational approach is required to understand the “big picture” coupling between disparate regions such as the solar-wind, magnetosphere, ionosphere, upper atmosphere, land, and ocean. However, the costs to date of these and other similar proposed constellations have been prohibitive given the traditional “large satellite” architectures and the multiple launch vehicles required for implementing the constellations.

Financially sustainable development and deployment of …


Rfbr: Radio Frequency Beacon Receiver, Space Dynamics Laboratory Jan 2014

Rfbr: Radio Frequency Beacon Receiver, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

The Space Dynamics Laboratory at Utah State University (SDL/USU), the Air Force Space and Missile Systems Center (SMC), and the Air Force Research Laboratory (AFRL) have teamed together to provide a portable ground-based radio frequency beacon receiver (RFBR) system capable of characterizing ionospheric parameters, including total electron content (TEC), amplitude, and phase scintillation. The system, derived almost entirely of COTS parts, can be configured to receive RF beacons such as those transmitted by existing on-orbit Coherent Electromagnetic Radio Tomography (CERTO) instrumentation, the upcoming Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC2), or other frequencies from VHF to S-band. By …


Compact Survey And Inspection Day/Night Image Sensor Suite For Small Unmanned Aircraft Systems (Eyepod), Alan Bird, Scott A. Anderson, Dale Linne Von Berg, Morgan Davidson, Niel Holt, Melvin Kruer, Michael L. Wilson Jan 2010

Compact Survey And Inspection Day/Night Image Sensor Suite For Small Unmanned Aircraft Systems (Eyepod), Alan Bird, Scott A. Anderson, Dale Linne Von Berg, Morgan Davidson, Niel Holt, Melvin Kruer, Michael L. Wilson

Space Dynamics Laboratory Publications

EyePod is a compact survey and inspection day/night imaging sensor suite for small unmanned aircraft systems (UAS). EyePod generates georeferenced image products in real-time from visible near infrared (VNIR) and long wave infrared (LWIR) imaging sensors and was developed under the ONR funded FEATHAR (Fusion, Exploitation, Algorithms, and Targeting for High-Altitude Reconnaissance) program. FEATHAR is being directed and executed by the Naval Research Laboratory (NRL) in conjunction with the Space Dynamics Laboratory (SDL) and FEATHAR’s goal is to develop and test new tactical sensor systems specifically designed for small manned and unmanned platforms (payload weight < 50 lbs). The EyePod suite consists of two VNIR/LWIR (day/night) gimbaled sensors that, combined, provide broad area survey and focused inspection capabilities. Each EyePod sensor pairs an HD visible EO sensor with a LWIR bolometric imager providing precision geo-referenced and fully digital EO/IR NITFS output imagery. The LWIR sensor is mounted to a patent-pending jitter-reduction stage to correct for the high-frequency motion typically found on small aircraft and unmanned systems. Details will be presented on both the wide-area and inspection EyePod sensor systems, their modes of operation, and results from recent flight demonstrations.


Development Of A Low-Cost Fine Steering Mirror, Steven R. Wassom, Morgan Davidson May 2008

Development Of A Low-Cost Fine Steering Mirror, Steven R. Wassom, Morgan Davidson

Space Dynamics Laboratory Publications

The Space Dynamics Laboratory has used internal funds to develop a prototype low-cost two-axis fine steering mirror (FSM) for space-based and airborne applications. The FSM has a lightweight 75 mm-by- 150-mm high-reflectance mirror, high angular deflection capability for along-track ground motion compensation and cross-track pointing, and a 70-Hertz bandwidth for small amplitudes to help cancel unwanted jitter. It makes use of off-the-shelf components as much as possible. Key performance parameters are: Clear aperture, 75 mm; elevation angle, ±15 deg (mechanical); azimuth angle, ±60 deg (mechanical); slew rate, greater than 75 deg/sec; bandwidth, 70 Hz; steady-state average error, about 1 arcsec; …


Cooling Saber With A Miniature Pulse Tube Refrigerator, Scott M. Jensen, J. Clair Batty, William A. Roettker, Matthew J. Felt Sep 1998

Cooling Saber With A Miniature Pulse Tube Refrigerator, Scott M. Jensen, J. Clair Batty, William A. Roettker, Matthew J. Felt

Space Dynamics Laboratory Publications

Utah State University/Space Dynamics Laboratory (USU/SDL), teaming with NASA Langley Research Center, is currently building the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER) instrument. Stringent mass and power constraints, together with a greater than two year mission life, led to the selection of a TRW miniature pulse tube refrigerator to cool SABER's infrared detectors to the required temperature of 75 K.

This paper provides an overview of the SABER thermal management plan and the challenges encountered in matching the refrigerator characteristics with instrument performance requirements under the broadly variant space environments expected for this mission. Innovative technologies were developed …