Research

Dr. Akos' research focuses on satellite navigation, particularly all aspects related to the receiver design/implementation. He pioneered the application of the software radio architecture to satellite navigation receiver design which has provided tremendous insight into the operational characteristics. He is the co-author of the text: A Software-Defined GPS and Galileo Receiver: A Single-Frequency Approach. His current research interest involve receiver design and testing for various GNSS, including GPS, GLONASS, Galileo, and Compass; utilizing GPS/GNSS for remote sensing; RFI/spoofing detection, localization, and mitigation algorithms for GPS/GNSS 

Dr. Natasha Bosanac’s research focuses on using the chaos of multi-body dynamical systems (e.g. Earth-Moon system, Sun-Earth system, binary star systems) to advance astrodynamics and celestial mechanics applications. For instance, leveraging the underlying dynamics of a system via equilibrium points, periodic orbits, quasi-periodic orbits and manifolds supports efficient and informed trajectory design approaches. Dr. Bosanac’s research group currently advances this strategy to enable and enhance a wide variety of complex missions, including:

• Applications from traditionally large monolithic spacecraft to smaller vehicles with a CubeSat or SmallSat form factor,
• Applications from individual spacecraft to formations or large swarms,
• Reducing the propulsive effort and/or flight time required for a given mission,
• Accommodating low-thrust and other propulsion systems in the design of feasible trajectories,
• Exploiting trajectory design to access new destinations within the solar system,
• Supporting reusability and longevity of space-based assets via robotic servicing, and
• Reducing the complexity and computational time required for trajectory design activities.
   

Earlier work included optimal orbit maneuvers, atmospheric entry theory, perturbations, and satellites’ atmospheric drag and decay. Dr. Culp recently served on the NRC Committee for Near-Earth Object Strategies and the Saving Planet Earth Report, and was a member of the NRC ISS Meteoroid and Debris Risk Committee. He has conducted major research over the past three decades in space debris and attendant problems.
 

Professor Holzinger's creative efforts addressing autonomy, controls & dynamical systems, and perception focus on a scholarly `theory to hardware' approach, wherein theoretical investigations are confirmed through empirical observations of on-orbit space objects.

To accomplish this, he has conscientiously incorporated real data collection in his program by constructing the Georgia Tech Space Object Research Telescope (GT- SORT), the Omnidirectional Space Situational Awareness (OmniSSA) Array, and working as the principal investigator for an Air Force cubesat program (RECONnaissance of Space Objects, RECONSO).

This combination of empirical data generation assets makes Dr. Holzinger's lab exceedingly unique, generating graduate students with strong theoretical foundations in astrodynamics, controls, and sensor systems, while also comfortable manipulating raw sensor data and operating the electro-optical assets themselves.

Kristine Larson focuses  on high-precision GPS applications, mostly for geoscientists. Her current research focuses on GPS reflections. The  reflections are used to study near-surface soil moisture, vegetation, and snow depth. A special effort focuses on developing water cycle products from EarthScope data: PBO H2O.

Tomoko Matsuo's main research interest is the design and development of statistical inferential methodologies for Earth and Geospace environmental observations, including the modeling of spatio-temporal random scalar and vector fields and designing sequential Monte Carlo methods for high-dimensional dynamical systems. She is fascinated by the process of unearthing and characterizing underlying statistical and physical properties hidden in data by means of statistical inference. Data assimilation is a good example of such a process.

Her research focuses on data assimilation of various types of remotely sensed and in-situ measurements into numerical models of Earth and Geospace systems, encompassing the Earth's whole atmosphere, ionosphere and magnetosphere. She is also interested in integrating design and development of engineering systems into geophysical modeling and prediction. Data assimilation provides an excellent framework for such investigation, and facilitates optimizing the instrumentation design and deployment of observing systems. Other areas of interest include the quantification of predictability of the whole atmosphere and ionosphere through applications of the dynamical systems theory, estimation theory, and information theory.

Dr. Jade Morton's research interests lie at the intersection of satellite navigation technologies (GPS/GNSS) and remote sensing of the ionosphere, atmosphere, and Earth surface using navigation satellite signals.  Her research team have been conducting experiments and developing new ground-based, airborne, and space-borned GPS/GNSS receiver technologies and algorithms for navigation in challenging environments and for monitoring space weather, troposphere structures, and ocean surface conditions.  

Dr. Palo's research focuses on remote sensing of the near Earth space environment, in particular the mesosphere and thermosphere, and the development of small satellite systems. Dr. Palo currently develops and deploys meteor radar systems to measure the winds in the mesosphere utilizing specular reflections from ionized meteor trails and shares space with Dr. Thayer in the Active Remote Sensing Lab (ARSenL). He is also involved with the development of pico and nanosatellites for space weather applications. Students in Dr. Palo's research group are engaged in the development of ground-based meteor radar and space hardware, analysis of radar and satellite observations and the use of atmospheric global circulation models. 
 

Dr. Scheeres’ research spans the topics of astrodynamics and spacecraft navigation to planetary science and celestial mechanics and has published extensively in these fields. One primary focus of Scheeres’ research is studying the mechanics of small bodies (such as moons and asteroids) with applications to planetary and asteroid missions. A separate focus of Scheeres' research is in the field of Space Situational Awareness, where his lab studies the dynamics and estimation of orbital debris and active satellites. Most recently, Scheeres is serving as the Radio Science Lead and Co-Investigator for NASA’s OSIRIS REx Asteroid Sample Return Mission. 

Dr. Williams’s research focuses on understanding the dynamics and microphysical processes occurring in precipitating cloud systems with the ultimate aim of improving rainfall estimation from space and improving numerical weather forecasting models. His research approach bridges the fields of engineering and geosciences. From an engineering prospective, his research analyzes ground, airborne, and satellite-based multi-frequency radar observations to estimate rainfall rate, vertical air motion, and the number and size of raindrops within clouds. Developing rainfall retrieval algorithms requires a technical understanding of radar systems, electromagnetic wave propagation, and numerical inverse retrieval methodologies. With regard to geosciences, his research relies on cloud microphysics and dynamics to convert radar-retrieved quantities into physical processes including raindrop breakup/coalescence and evaporation. Dr. Williams also develops innovative radar systems and signal processing techniques needed to answer new research questions.