subject:(Orbit Propagation)

University of Colorado

1. Jones, Brandon Allan. Efficient Models for the Evaluation and Estimation of the Gravity Field.

Degree: PhD, Aerospace Engineering Sciences, 2010, University of Colorado

URL: https://scholar.colorado.edu/asen_gradetds/11

► Current astrodynamics applications require a rapid evaluation of the gravity field and an efficient approach to gravity estimation. The commonly used spherical harmonic model… (more)

▼ Current astrodynamics applications require a rapid evaluation of the gravity field and an efficient approach to gravity estimation. The commonly used spherical harmonic model does not meet either of these needs. To address these issues, this research considers two new gravity representations: the cubed-sphere and the MRQSphere models. Offering a means for rapid evaluation, the cubed-sphere model yields an effectively constant computation time for any degree of the modeled gravity field. Analyzing the model's performance in a series of Monte-Carlo-like tests characterizes its effects on both orbit propagation and determination. When compared to the spherical harmonic gravity model, the cubed-sphere model improves computational efficiency without causing any significant deviation in resulting trajectories. Using this new model in sequential orbit determination improves the computational efficiency of the time update. As a result, the measurement update now dominates the filter execution time for near real-time applications. Since cubed-sphere models of higher degree require only a slight change in computation time, orbit propagation and determination systems may now use this model to improve fidelity without any significant change in cost. To address the gravity estimation problem, combining a new multiresolution technique with nearly optimal quadratures (for the sphere) invariant under the icosahedral group defines the MRQSphere model. This new multiresolution representation allows for gravity estimation via a naturally staged approach to a celestial body with an unknown gravity field, which aids in the design of missions to small bodies. To test the new model's capabilities, this research simulates a mission to an asteroid. Tests include the characterization of a MRQSphere model derived from the asteroid's spherical harmonic model, and the estimation of a model via observations of the gravity potential. For such a simplified scenario, the results indicate that the MRQSphere model meets the estimation accuracy requirements; future work is recommended to fully explore its capabilities. Advisors/Committee Members: George H. Born, Gregory Beylkin, Daniel J. Schneeres.

Subjects/Keywords: asteroid; gravity estimation; gravity modeling; orbit determination; orbit propagation; spherical harmonics; Aerospace Engineering; Astrodynamics

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APA (6^th Edition):

Jones, B. A. (2010). Efficient Models for the Evaluation and Estimation of the Gravity Field. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/asen_gradetds/11

Chicago Manual of Style (16^th Edition):

Jones, Brandon Allan. “Efficient Models for the Evaluation and Estimation of the Gravity Field.” 2010. Doctoral Dissertation, University of Colorado. Accessed January 18, 2021. https://scholar.colorado.edu/asen_gradetds/11.

MLA Handbook (7^th Edition):

Jones, Brandon Allan. “Efficient Models for the Evaluation and Estimation of the Gravity Field.” 2010. Web. 18 Jan 2021.

Vancouver:

Jones BA. Efficient Models for the Evaluation and Estimation of the Gravity Field. [Internet] [Doctoral dissertation]. University of Colorado; 2010. [cited 2021 Jan 18]. Available from: https://scholar.colorado.edu/asen_gradetds/11.

Council of Science Editors:

Jones BA. Efficient Models for the Evaluation and Estimation of the Gravity Field. [Doctoral Dissertation]. University of Colorado; 2010. Available from: https://scholar.colorado.edu/asen_gradetds/11

Penn State University

2. Kuppa, Koundinya. Long-term Orbit Propagation Using Symplectic Integration Algorithms.

Degree: 2016, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/29463

► Understanding the evolution of satellite orbits in the long-term is of great importance in astrodynamics. In order to achieve this, accurate propagation of the orbital… (more)

Subjects/Keywords: astrodynamics; orbital mechanics; symplectic integration; numerical integration; orbit propagation; spaceflight mechanics

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APA (6^th Edition):

Kuppa, K. (2016). Long-term Orbit Propagation Using Symplectic Integration Algorithms. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/29463

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kuppa, Koundinya. “Long-term Orbit Propagation Using Symplectic Integration Algorithms.” 2016. Thesis, Penn State University. Accessed January 18, 2021. https://submit-etda.libraries.psu.edu/catalog/29463.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kuppa, Koundinya. “Long-term Orbit Propagation Using Symplectic Integration Algorithms.” 2016. Web. 18 Jan 2021.

Vancouver:

Kuppa K. Long-term Orbit Propagation Using Symplectic Integration Algorithms. [Internet] [Thesis]. Penn State University; 2016. [cited 2021 Jan 18]. Available from: https://submit-etda.libraries.psu.edu/catalog/29463.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kuppa K. Long-term Orbit Propagation Using Symplectic Integration Algorithms. [Thesis]. Penn State University; 2016. Available from: https://submit-etda.libraries.psu.edu/catalog/29463

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology

3. Pinardell Pons, Aleix (author). GTO debris mitigation using natural perturbations.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:f550d59a-7d15-46dd-a084-025ace46e643

► Objects ingeostationary transfer orbit (GTO) can collide with operative satellites in lowEarth orbit (LEO) and geostationary orbit (GEO). Various organisationshave laid down debris-mitigation guidelines that… (more)

▼ Objects ingeostationary transfer orbit (GTO) can collide with operative satellites in lowEarth orbit (LEO) and geostationary orbit (GEO). Various organisationshave laid down debris-mitigation guidelines that will be enforced by law forfuture launchers. One of the guidelines entails proving that the generateddebris will re-enter in less than 25 years with a 90% probability. Naturalperturbations can be exploited to meet this requirement without the use ofextra propellant or complex de-orbiting systems, which is especially attractivefrom an economic point of view. Objects in GTO can undergo a resonancetriggered by an interplay between perturbations caused by the Sun’s gravity andthe irregularities in Earth’s gravity field, leading to a sudden re-entryor making the object stay in orbit for decades. This effect is very sensitiveto initial conditions because it depends on the relative positions of theperigee and the Sun when the semi-major axis is close to 15000 km.By simulating the orbital evolution of a representative GTO object—ballistic coefficient of 0.011 m²/kg, initial orbital inclination of 10degrees and initial perigee altitude of 200 km— for several initialepochs, it was found that favourable launch conditions take place twice perday during most part of the year, while for epochs close to the equinoxesof March and September they only happen once per day or not at all. Giventhe high sensitivity to initial conditions, the problem was studied from astatistical perspective, taking into account the uncertainties in thevalues of the relevant parameters. Semi-analytical techniques were used topropagate the mean equinoctial elements instead of the osculatingCartesian elements, which reduced computation times by a factor of 45 whilestill keeping proper levels of accuracy. Current practice for GTO launches fromKourou is to launch at around 6-7 PM. It was found that the launchtime leading to the highest probability of compliance with debris-mitigationguidelines for GEO launches from the European spaceport in Kourou isslightly later, regardless of the day of the year, although the value of theoptimal lifetime does vary slightly throughout the year. Thus, achange in procedures would be required in order to reach a higher degreeof compliance with debris-mitigation guidelines, which was below 10% for GTOlaunches carried out with Ariane 5 from in the period 2004-2012. Advisors/Committee Members: Noomen, Ron (mentor), Stam, Daphne (graduation committee), Chu, Qiping (graduation committee), Delft University of Technology (degree granting institution).

Subjects/Keywords: GTO; debris; mitigation; semi-analytical propagation; Orbit modeling; perturbations

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APA (6^th Edition):

Pinardell Pons, A. (. (2017). GTO debris mitigation using natural perturbations. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:f550d59a-7d15-46dd-a084-025ace46e643

Chicago Manual of Style (16^th Edition):

Pinardell Pons, Aleix (author). “GTO debris mitigation using natural perturbations.” 2017. Masters Thesis, Delft University of Technology. Accessed January 18, 2021. http://resolver.tudelft.nl/uuid:f550d59a-7d15-46dd-a084-025ace46e643.

MLA Handbook (7^th Edition):

Pinardell Pons, Aleix (author). “GTO debris mitigation using natural perturbations.” 2017. Web. 18 Jan 2021.

Vancouver:

Pinardell Pons A(. GTO debris mitigation using natural perturbations. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 18]. Available from: http://resolver.tudelft.nl/uuid:f550d59a-7d15-46dd-a084-025ace46e643.

Council of Science Editors:

Pinardell Pons A(. GTO debris mitigation using natural perturbations. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:f550d59a-7d15-46dd-a084-025ace46e643

Virginia Tech

4. Berry, Matthew M. A Variable-Step Double-Integration Multi-Step Integrator.

Degree: PhD, Aerospace and Ocean Engineering, 2004, Virginia Tech

URL: http://hdl.handle.net/10919/11155

► A new method of numerical integration is presented here, the variable-step Stormer-Cowell method. The method uses error control to regulate the step size, so larger… (more)

Subjects/Keywords: Variable-Step Integration; Orbit Propagation; Orbit Determination; Numerical Integration

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APA (6^th Edition):

Berry, M. M. (2004). A Variable-Step Double-Integration Multi-Step Integrator. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/11155

Chicago Manual of Style (16^th Edition):

Berry, Matthew M. “A Variable-Step Double-Integration Multi-Step Integrator.” 2004. Doctoral Dissertation, Virginia Tech. Accessed January 18, 2021. http://hdl.handle.net/10919/11155.

MLA Handbook (7^th Edition):

Berry, Matthew M. “A Variable-Step Double-Integration Multi-Step Integrator.” 2004. Web. 18 Jan 2021.

Vancouver:

Berry MM. A Variable-Step Double-Integration Multi-Step Integrator. [Internet] [Doctoral dissertation]. Virginia Tech; 2004. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10919/11155.

Council of Science Editors:

Berry MM. A Variable-Step Double-Integration Multi-Step Integrator. [Doctoral Dissertation]. Virginia Tech; 2004. Available from: http://hdl.handle.net/10919/11155

Texas A&M University

5. Macomber, Brent David. Enhancements to Chebyshev-Picard Iteration Efficiency for Generally Perturbed Orbits and Constrained Dynamical Systems.

Degree: PhD, Aerospace Engineering, 2015, Texas A&M University

URL: http://hdl.handle.net/1969.1/155745

► Modified Chebyshev Picard Iteration (MCPI) is an iterative numerical method for solution of Ordinary Differential Equations (ODEs). This dissertation presents a body of work that… (more)

▼ Modified Chebyshev Picard Iteration (MCPI) is an iterative numerical method for solution of Ordinary Differential Equations (ODEs). This dissertation presents a body of work that serves to enhance the overall performance and the algorithmic automation of MCPI, applied to the problem of perturbed orbit propagation. Additionally, an MCPI framework is derived that greatly improves MCPI performance for ODE systems that intrinsically have associated conserved quantities. Leveraging these developments, software libraries are presented that are designed to make MCPI more accessible and automated, both for the problem of orbit propagation, and for general ODE systems. The work outlined in this document is the result of an effort to promote MCPI from an algorithm of academic interest to a broadly applicable toolset for general use by researchers worldwide in all disciplines. MCPI is able to numerically propagate perturbed orbits to arbitrarily high solution accuracy, bounded by the limits of numerical precision. The improvements to MCPI for orbit propagation are focused on decreasing the computational cost of high-accuracy propagation in a two-fold manner; by reducing the number of required iterations necessary to achieve convergence, and decreasing the computational cost per iteration. Typically, the spherical harmonic gravity function evaluations are the most computationally expensive part of perturbed orbit propagation, so the strategies for reducing the cost per iteration focus on techniques for reducing the cost of gravity series evaluations. Additionally, automated tuning parameter selection logic is introduced to enable MCPI to propagate large batches of perturbed orbits, without the necessity of a user in the loop. By making use of an associated conserved quantity within applicable ODE systems, MCPI is shown to be able to achieve much higher performance. A first order and a second order constrained MCPI formulation are developed that are able to vastly reduce the required number of iterations for convergence, increase the achievable segment length, and increase the overall solution accuracy for a given convergence threshold. Software libraries are presented with the goal of encouraging widespread use of the MCPI method. Serial libraries are available for general ODE systems, akin to the Matlab ODE** methods. More specialized libraries, making use of the computational improvements and automated tuning, are available for perturbed orbit propagation. A parallel framework based upon the orbit propagation libraries is presented that is designed for space catalog maintenance, uncertainty propagation, or conjunction analysis. Advisors/Committee Members: Junkins, John L (advisor), Datta, Aniruddha (committee member), Hurtado, John E (committee member), Turner, James D (committee member).

Subjects/Keywords: Numerical Methods; Ordinary Differential Equations; Parallel Computing; Orbit Propagation; Space Situational Awareness

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APA (6^th Edition):

Macomber, B. D. (2015). Enhancements to Chebyshev-Picard Iteration Efficiency for Generally Perturbed Orbits and Constrained Dynamical Systems. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/155745

Chicago Manual of Style (16^th Edition):

Macomber, Brent David. “Enhancements to Chebyshev-Picard Iteration Efficiency for Generally Perturbed Orbits and Constrained Dynamical Systems.” 2015. Doctoral Dissertation, Texas A&M University. Accessed January 18, 2021. http://hdl.handle.net/1969.1/155745.

MLA Handbook (7^th Edition):

Macomber, Brent David. “Enhancements to Chebyshev-Picard Iteration Efficiency for Generally Perturbed Orbits and Constrained Dynamical Systems.” 2015. Web. 18 Jan 2021.

Vancouver:

Macomber BD. Enhancements to Chebyshev-Picard Iteration Efficiency for Generally Perturbed Orbits and Constrained Dynamical Systems. [Internet] [Doctoral dissertation]. Texas A&M University; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1969.1/155745.

Council of Science Editors:

Macomber BD. Enhancements to Chebyshev-Picard Iteration Efficiency for Generally Perturbed Orbits and Constrained Dynamical Systems. [Doctoral Dissertation]. Texas A&M University; 2015. Available from: http://hdl.handle.net/1969.1/155745

University of Oregon

6. Vitullo, Dashiell. Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation.

Degree: PhD, Department of Physics, 2016, University of Oregon

URL: http://hdl.handle.net/1794/20708

► We investigate two medium-facilitated interactions between properties of light upon propagation through optical fiber. The first is interaction between the spin and intrinsic orbital angular… (more)

▼ We investigate two medium-facilitated interactions between properties of light upon propagation through optical fiber. The first is interaction between the spin and intrinsic orbital angular momentum in a linear optical medium. This interaction gives rise to fine structure in the longitudinal momenta of fiber modes and manifests in rotational beating effects. We probe those beating effects experimentally in cutback experiments, where small segments are cut from the output of a fiber to probe the evolution of both output polarization and spatial orientation, and find agreement between theoretical predictions and measured behavior. The second is nonlinear optical interaction due to cross- and self-phase modulation between the complex-valued temporal amplitude profile of pump pulses and the amplitude profiles of generated signal and idler pulses in optical fiber photon-pair sources utilizing the four-wave mixing process named modulation instability. We develop a model including the effects of these nonlinear phase modulations (NPM) describing the time-domain wave function of the output biphoton in the low-gain regime. Assuming Gaussian temporal amplitude profiles for the pump pulse, we numerically simulate the structure of the biphoton wave function, in symmetric and asymmetric group velocity matching configurations. Comparing the overlap of the joint temporal amplitudes with and without NPM indicates how good of an approximation neglecting NPM is, and we investigate the effects of NPM on the Schmidt modes. We find that effects of NPM are small on temporally separable sources utilizing symmetric group velocity matching, but appreciably change the state of temporally entangled sources with the same group velocity matching scheme. For sources designed to produce entangled biphotons, our simulations suggest that NPM increases the Schmidt number, which may increase entanglement resource availability with utilization of a phase-sensitive detection scheme. We find that NPM effects on temporally separable sources designed with asymmetric group velocity matching produce non-negligible changes in the state structure. The purity is unaffected at perfect asymmetric group velocity matching, but if the pump is detuned from the correct wavelength, the purity degrades. The largest changes to the state due to NPM occur in long fibers with long pulse durations and low repetition rates. Advisors/Committee Members: Raymer, Michael (advisor).

Subjects/Keywords: Fiber optics; Nonlinear optics; Orbital angular momentum; Propagation; Quantum optics; Spin-orbit interaction

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APA (6^th Edition):

Vitullo, D. (2016). Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation. (Doctoral Dissertation). University of Oregon. Retrieved from http://hdl.handle.net/1794/20708

Chicago Manual of Style (16^th Edition):

Vitullo, Dashiell. “Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation.” 2016. Doctoral Dissertation, University of Oregon. Accessed January 18, 2021. http://hdl.handle.net/1794/20708.

MLA Handbook (7^th Edition):

Vitullo, Dashiell. “Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation.” 2016. Web. 18 Jan 2021.

Vancouver:

Vitullo D. Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation. [Internet] [Doctoral dissertation]. University of Oregon; 2016. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1794/20708.

Council of Science Editors:

Vitullo D. Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation. [Doctoral Dissertation]. University of Oregon; 2016. Available from: http://hdl.handle.net/1794/20708

7. McCullough, Christopher Michael. Numerical integration accuracy and modeling for future geodetic missions.

Degree: MSin Engineering, Aerospace Engineering, 2013, University of Texas – Austin

URL: http://hdl.handle.net/2152/21204

► As technological advances throughout the field of satellite geodesy improve the accuracy of satellite measurements, numerical methods and algorithms must be able to keep pace.… (more)

▼ As technological advances throughout the field of satellite geodesy improve the accuracy of satellite measurements, numerical methods and algorithms must be able to keep pace. This becomes increasingly important for high precision applications, such as high degree/order gravity field recovery. Currently, the Gravity Recovery and Climate Experiment's (GRACE) dual one-way microwave ranging system can determine changes in inter-satellite range to a precision of a few microns; however, with the advent of laser measurement systems nanometer precision ranging is a realistic possibility. With this increase in measurement accuracy, a reevaluation of the accuracy inherent in the numerical integration algorithms is necessary. This study attempts to quantify and minimize these numerical errors in an effort to improve the accuracy of modeling and propagation of various orbital perturbations; helping to provide further insight into the behavior and evolution of the Earth's gravity field from the more capable gravity missions in the future. The numerical integration errors are examined for a variety of satellite accelerations. The propagation of orbits similar to those of the GRACE satellites using a gravitational model that assumes the Earth is a perfect sphere show integration errors, using double precision numerical representations, on the order of 1 micron in inter-satellite range and 0.1 nanometers per second in inter-satellite range-rate. In addition, when the Earth's gravitational field is formulated in spherical harmonics these numerical integration errors begin to contaminate signals to due harmonics approximately above degree 220, for an orbit at GRACE altitudes. Also, when examining the effect of mass anomalies on the Earth's surface, simulated as point masses, it is apparent that numerical integration methods are easily capable of resolving point mass anomalies as small as 0.05 gigatonnes. Finally, a numerical integration procedure is determined to accurately simulate the effect of numerous, small step accelerations applied to the satellite's center of mass due to misalignment and misfiring of the attitude thrusters. Future studies can then use this procedure as a metric to evaluate the accuracy and effectiveness of an accelerometer in reproducing these non-gravitational forces and how these errors might affect gravity field recovery. Advisors/Committee Members: Bettadpur, Srinivas Viswanath, 1963- (advisor).

Subjects/Keywords: GRACE; Numerical integration; Orbit propagation

…gravity field harmonics for 95 minute low Earth orbit… …orbit the Earth in a near circular and near polar orbit at an altitude of approximately 500… …orbit the Earth, they experience small accelerations due to the non-uniformity of the gravity… …satellite’s orbit to at least the nanometer per second level, the computed observations, y, will be… …accelerations imparted on the satellites while in orbit. These algorithms can be very simple, such as…

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APA (6^th Edition):

McCullough, C. M. (2013). Numerical integration accuracy and modeling for future geodetic missions. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/21204

Chicago Manual of Style (16^th Edition):

McCullough, Christopher Michael. “Numerical integration accuracy and modeling for future geodetic missions.” 2013. Masters Thesis, University of Texas – Austin. Accessed January 18, 2021. http://hdl.handle.net/2152/21204.

MLA Handbook (7^th Edition):

McCullough, Christopher Michael. “Numerical integration accuracy and modeling for future geodetic missions.” 2013. Web. 18 Jan 2021.

Vancouver:

McCullough CM. Numerical integration accuracy and modeling for future geodetic missions. [Internet] [Masters thesis]. University of Texas – Austin; 2013. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2152/21204.

Council of Science Editors:

McCullough CM. Numerical integration accuracy and modeling for future geodetic missions. [Masters Thesis]. University of Texas – Austin; 2013. Available from: http://hdl.handle.net/2152/21204

Indian Institute of Science

8. Akila, S. Orbit Model Analysis And Dynamic Filter Compensation For Onboard Autonomy.

Degree: PhD, Faculty of Science, 2009, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/398

► Orbit of a spacecraft in three dimensional Inertial Reference Frame is in general represented by a standard set of six parameters like Keplerian Orbital Elements… (more)

▼ Orbit of a spacecraft in three dimensional Inertial Reference Frame is in general represented by a standard set of six parameters like Keplerian Orbital Elements namely semimajor axis, eccentricity, inclination, argument of perigee, right ascension of ascending node, and true anomaly. An orbit can also be represented by an equivalent set of six parameters namely the position and velocity vectors, hereafter referred as orbit-vectors. The process of determining the six orbital parameters from redundant set of observations (more than the required minimum observations) is known as Orbit Determination (OD) process. This is, in general, solved using Least Squares principle. Availability of accurate, almost continuous, space borne observations provide tremendous scope for simplifications and new directions in Autonomous OD (AOD). The objective of this thesis is to develop a suitable scheme for onboard autonomy in OD, specifically for low-earth-orbit-missions that are in high demand in the immediate future. The focus is on adopting a simple orbit model by a thorough study and analysis by considering the individual contributions from the different force models or component accelerations acting on the spacecraft. Second step in this work is to address the application of an onboard estimation scheme like Kalman Filter for onboard processing. The impact of the approximation made in the orbit model for filter implementation manifests as propagation error or estimation residuals in the estimation. The normal procedure of tuning the filter is by getting an appropriate state and measurement noise covariance matrices by some means, sometimes through trial and error basis. Since this tuning is laborious and the performance may vary with different contexts, it is attempted to propose a scheme on a more general footing, with dynamically compensating for the model simplification. There are three parts of this problem namely (i) Analysis of different Orbit Dynamics Models and selection of a simplified Onboard Model (ii) Design of an Estimator Filter based on Kalman Filter approach for Onboard Applications and (iii) Development of a suitable Filter Compensation procedure to ensure best estimates of orbit vectors even with the simplified orbit model. Development of a Numerical Integration scheme (and a software tool) and extensive simulation exercises to justify the conclusion on the simple model to be used in the estimation procedure forms the first part of the thesis. Tables quantify the effect of individual accelerations and demonstrate the effects of various model components on orbit propagation. In general, it is well known that the atmospheric drag is a non-conservative force and reduces energy; it is also known that the effect of first zonal harmonic term is predominant than any other … Advisors/Committee Members: Ghosh, M K (advisor), Krishnakumar, E (advisor).

Subjects/Keywords: Orbit Models; Spacecraft Orbits; Dynamic Filters; Orbit Dynamics; Orbit Determination (OD); Orbit Propagation; Kalman Filter; Dynamics Filter Compensation (DFC); Astronautics

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APA (6^th Edition):

Akila, S. (2009). Orbit Model Analysis And Dynamic Filter Compensation For Onboard Autonomy. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/398

Chicago Manual of Style (16^th Edition):

Akila, S. “Orbit Model Analysis And Dynamic Filter Compensation For Onboard Autonomy.” 2009. Doctoral Dissertation, Indian Institute of Science. Accessed January 18, 2021. http://etd.iisc.ac.in/handle/2005/398.

MLA Handbook (7^th Edition):

Akila, S. “Orbit Model Analysis And Dynamic Filter Compensation For Onboard Autonomy.” 2009. Web. 18 Jan 2021.

Vancouver:

Akila S. Orbit Model Analysis And Dynamic Filter Compensation For Onboard Autonomy. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2009. [cited 2021 Jan 18]. Available from: http://etd.iisc.ac.in/handle/2005/398.

Council of Science Editors:

Akila S. Orbit Model Analysis And Dynamic Filter Compensation For Onboard Autonomy. [Doctoral Dissertation]. Indian Institute of Science; 2009. Available from: http://etd.iisc.ac.in/handle/2005/398

University of Colorado

9. Bradley, Ben K. Numerical Algorithms for Precise and Efficient Orbit Propagation and Positioning.

Degree: PhD, Aerospace Engineering Sciences, 2015, University of Colorado

URL: https://scholar.colorado.edu/asen_gradetds/125

► Motivated by the growing space catalog and the demands for precise orbit determination with shorter latency for science and reconnaissance missions, this research improves… (more)

▼ Motivated by the growing space catalog and the demands for precise orbit determination with shorter latency for science and reconnaissance missions, this research improves the computational performance of orbit propagation through more efficient and precise numerical integration and frame transformation implementations. Propagation of satellite orbits is required for astrodynamics applications including mission design, orbit determination in support of operations and payload data analysis, and conjunction assessment. Each of these applications has somewhat different requirements in terms of accuracy, precision, latency, and computational load. This dissertation develops procedures to achieve various levels of accuracy while minimizing computational cost for diverse orbit determination applications. This is done by addressing two aspects of orbit determination: (1) numerical integration used for orbit propagation and (2) precise frame transformations necessary for force model evaluation and station coordinate rotations. This dissertation describes a recently developed method for numerical integration, dubbed Bandlimited Collocation Implicit Runge-Kutta (BLC-IRK), and compare its efficiency in propagating orbits to existing techniques commonly used in astrodynamics. The BLC-IRK scheme uses generalized Gaussian quadratures for bandlimited functions. It requires significantly fewer force function evaluations than explicit Runge-Kutta schemes and approaches the efficiency of the 8th-order Gauss-Jackson multistep method. Converting between the Geocentric Celestial Reference System (GCRS) and International Terrestrial Reference System (ITRS) is necessary for many applications in astrodynamics, such as orbit propagation, orbit determination, and analyzing geoscience data from satellite missions. This dissertation provides simplifications to the Celestial Intermediate Origin (CIO) transformation scheme and Earth orientation parameter (EOP) storage for use in positioning and orbit propagation, yielding savings in computation time and memory. Orbit propagation and position transformation simulations are analyzed to generate a complete set of recommendations for performing the ITRS/GCRS transformation for a wide range of needs, encompassing real-time on-board satellite operations and precise post-processing applications. In addition, a complete derivation of the ITRS/GCRS frame transformation time-derivative is detailed for use in velocity transformations between the GCRS and ITRS and is applied to orbit propagation in the rotating ITRS. EOP interpolation methods and ocean tide corrections are shown to impact the ITRS/GCRS transformation accuracy at the level of 5 cm and 20 cm on the surface of the Earth and at the Global Positioning System (GPS) altitude, respectively. The precession-nutation and EOP simplifications yield maximum propagation errors of approximately 2 cm and 1 m after 15 minutes and 6 hours in low-Earth orbit (LEO), respectively, while reducing computation time and memory usage. Finally,… Advisors/Committee Members: Penina Axelrad, George H. Born, Brandon A. Jones, Webster Cash, Daniel J. Scheeres.

Subjects/Keywords: Earth orientation parameters; International Terrestrial Reference System; Orbit propagation; Precise frame transformations; Navigation, Guidance, Control and Dynamics

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APA (6^th Edition):

Bradley, B. K. (2015). Numerical Algorithms for Precise and Efficient Orbit Propagation and Positioning. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/asen_gradetds/125

Chicago Manual of Style (16^th Edition):

Bradley, Ben K. “Numerical Algorithms for Precise and Efficient Orbit Propagation and Positioning.” 2015. Doctoral Dissertation, University of Colorado. Accessed January 18, 2021. https://scholar.colorado.edu/asen_gradetds/125.

MLA Handbook (7^th Edition):

Bradley, Ben K. “Numerical Algorithms for Precise and Efficient Orbit Propagation and Positioning.” 2015. Web. 18 Jan 2021.

Vancouver:

Bradley BK. Numerical Algorithms for Precise and Efficient Orbit Propagation and Positioning. [Internet] [Doctoral dissertation]. University of Colorado; 2015. [cited 2021 Jan 18]. Available from: https://scholar.colorado.edu/asen_gradetds/125.

Council of Science Editors:

Bradley BK. Numerical Algorithms for Precise and Efficient Orbit Propagation and Positioning. [Doctoral Dissertation]. University of Colorado; 2015. Available from: https://scholar.colorado.edu/asen_gradetds/125

10. Reinthal, Eric. Relative Orbit Propagation and Control for Satellite Formation Flying using Continuous Low-thrust.

Degree: Electrical and Space Engineering, 2017, Luleå University of Technology

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61664

► For the upcoming formation flying technology demonstration mission NetSat a relative orbit propagator as well as a relative orbit controller were developed. The formation… (more)

Subjects/Keywords: formation flying; low-thrust; orbit propagation; control; continuous thrust; NetSat; electric propulsion; Aerospace Engineering; Rymd- och flygteknik

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APA (6^th Edition):

Reinthal, E. (2017). Relative Orbit Propagation and Control for Satellite Formation Flying using Continuous Low-thrust. (Thesis). Luleå University of Technology. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61664

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Reinthal, Eric. “Relative Orbit Propagation and Control for Satellite Formation Flying using Continuous Low-thrust.” 2017. Thesis, Luleå University of Technology. Accessed January 18, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61664.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Reinthal, Eric. “Relative Orbit Propagation and Control for Satellite Formation Flying using Continuous Low-thrust.” 2017. Web. 18 Jan 2021.

Vancouver:

Reinthal E. Relative Orbit Propagation and Control for Satellite Formation Flying using Continuous Low-thrust. [Internet] [Thesis]. Luleå University of Technology; 2017. [cited 2021 Jan 18]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61664.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Reinthal E. Relative Orbit Propagation and Control for Satellite Formation Flying using Continuous Low-thrust. [Thesis]. Luleå University of Technology; 2017. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-61664

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Delft University of Technology

11. Nardi, Alex (author). Orbit Modeling of Galilean Moons Flybys.

Degree: 2017, Delft University of Technology

URL: http://resolver.tudelft.nl/uuid:38e13f1e-8424-4a00-bbad-70b9eadf97ac

► This research aims at modeling the trajectory followed by the Galileo spacecraft during a variety of flybys about the Galilean moons. The chosen flybys have… (more)

▼ This research aims at modeling the trajectory followed by the Galileo spacecraft during a variety of flybys about the Galilean moons. The chosen flybys have good Earth’s elevation angles and either low or high closest-approach altitudes, so that the comparison of the two can give relevant insight into the accuracy of the corresponding trajectories. By propagating the state of the spacecraft during these flybys, optimizing the nominal initial state of the spacecraft (obtained through the SPICE program) and the spherical harmonics of the moons, and estimating new harmonics, the minimum root mean square error between the resulting trajectory and the ephemerides by Jet Propulsion Laboratory (JPL) is found. The analysis of its components along the Local Orbital axes gives insight into the existing relation between them and the Earth's elevation and azimuth angles. In particular, a low-altitude flyby implies in general a higher error, but when two flybys have similar altitudes, then the Earth's elevation plays a relevant role and the flyby with the largest one is more likely to have a larger error too. The root mean square error of the fitted trajectories can vary from 15 cm to 7 m, so always less than the 9 m declared by National Aeronautics and Space Administration (NASA) as the maximum error of the moons ephemerides. Furthermore, the flybys about Ganymede and Callisto show a high error in the along-track and cross-track directions, since the radius of their sphere of influence is quite larger than that of the inner moons' ones, hence there is more time for the perturbations to influence the orbit. A by-product of this research is the estimate of the Galilean moons' gravity field, in particular the new values for their J2 and C2,2 coefficients led to the conclusion that Io is less hydrostatic, while Europa and Callisto are more hydrostatic than previously thought. Advisors/Committee Members: Noomen, Ron (mentor), Delft University of Technology (degree granting institution).

Subjects/Keywords: Galilean moons; Orbit modeling; Flyby; Hydrostaticity; Gravity field; Spherical harmonics; MATLAB; Integration; Propagation; Optimization; Data fitting

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APA (6^th Edition):

Nardi, A. (. (2017). Orbit Modeling of Galilean Moons Flybys. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:38e13f1e-8424-4a00-bbad-70b9eadf97ac

Chicago Manual of Style (16^th Edition):

Nardi, Alex (author). “Orbit Modeling of Galilean Moons Flybys.” 2017. Masters Thesis, Delft University of Technology. Accessed January 18, 2021. http://resolver.tudelft.nl/uuid:38e13f1e-8424-4a00-bbad-70b9eadf97ac.

MLA Handbook (7^th Edition):

Nardi, Alex (author). “Orbit Modeling of Galilean Moons Flybys.” 2017. Web. 18 Jan 2021.

Vancouver:

Nardi A(. Orbit Modeling of Galilean Moons Flybys. [Internet] [Masters thesis]. Delft University of Technology; 2017. [cited 2021 Jan 18]. Available from: http://resolver.tudelft.nl/uuid:38e13f1e-8424-4a00-bbad-70b9eadf97ac.

Council of Science Editors:

Nardi A(. Orbit Modeling of Galilean Moons Flybys. [Masters Thesis]. Delft University of Technology; 2017. Available from: http://resolver.tudelft.nl/uuid:38e13f1e-8424-4a00-bbad-70b9eadf97ac

12. Álvaro de Albuquerque Arraes. Propagation of uncertainties in the navigation of aerospace vehicles to minimize or maximize the collision risk.

Degree: 2008, Instituto Nacional de Pesquisas Espaciais

URL: http://urlib.net/sid.inpe.br/[email protected]/2008/10.14.00.42

►

Neste trabalho realizou-se o estudo de diversas idéias relacionadas ao problema do cálculo de probabilidade de colisão de satélites. Com base nessas idéias, foi realizada… (more)

▼

Neste trabalho realizou-se o estudo de diversas idéias relacionadas ao problema do cálculo de probabilidade de colisão de satélites. Com base nessas idéias, foi realizada a simulação de métodos para propagação de incertezas na navegação de veículos aeroespaciais e determinação de risco de colisões, visando sua minimização ou maximização. Utilizou-se como cenário de simulação a situação de satélites em formação, estudando os aspectos de predição de probabilidade de colisão. As seguintes restrições foram consideradas: a preocupação com a operação em tempo real, com seu requisito de previsibilidade de tempo máximo de execução, determinou a necessidade de estabelecer critérios de parada para os algoritmos; os cenários foram considerados cooperativos. O trabalho foi focado na minimização dos riscos de colisão. Além disso, procurou-se fazer uma extensão para o cenário aeronáutico, buscando identificar a possibilidade de aproveitar algumas das idéias para casos em que o risco de colisão de aeronaves é maior. A autoridade da torre de controle foi considerada como o controlador responsável pela reconfiguração das rotas das aeronaves. O trabalho tem o potencial de vir a ser estendido para cenários espaciais e/ou aeronáuticos com as seguintes restrições: o sistema deverá operar em tempo real (tempo de convergência do método / algoritmo deverá ser determinístico); os cenários serão considerados não cooperativos; e se visará maximizar o risco de colisão.

In this work, some ideas related to probability of satellite collision were studied and, based on them, the simulation of methods for the propagation of navigation uncertainties in the trajectory of aerospace vehicles was performed in order to minimize or maximize the risk of collisions. The scenario of Satellites Formation Flying was used for the simulations, with focus on the prediction of the collision probability. The following restrictions apply: the concern about developing real time methods, with its requirement for maximum time foreseeability for the employed method determined that stop criteria for the algorithms were established; the scenarios were cooperative; and the minimization of the collision risk was envisaged. The discussion was extended to aeronautical scenarios, with the attempt to identify commonalities that could lead to the use of the same ideas to the problem of aircraft collision. The control tower was considered the authority responsible for rerouting the airplanes. This work has the potential to be extended to space and/or aeronautical scenarios, with the following restrictions: the system shall work in real time (deterministic time for the employed method / algorithm); the scenarios shall be noncooperative; and the maximization of the collision risk shall be envisaged.

Advisors/Committee Members: Mário César Ricci, Marcelo Lopes de Oliveira e Souza, Evandro Marconi Rocco, Antônio Fernando Bertachini de Almeida Prado, Hélio Koiti Kuga, Marcelo Curvo.

Subjects/Keywords: formação de satélites; estimação de trajetória; propagação de matriz de covariancia; detritos espaciais; collision avoidance; satellite formation flying; orbit prediction; covariance propagation; debris; elisão de colisão

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APA (6^th Edition):

Arraes, �. d. A. (2008). Propagation of uncertainties in the navigation of aerospace vehicles to minimize or maximize the collision risk. (Thesis). Instituto Nacional de Pesquisas Espaciais. Retrieved from http://urlib.net/sid.inpe.br/[email protected]/2008/10.14.00.42

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Arraes, Álvaro de Albuquerque. “Propagation of uncertainties in the navigation of aerospace vehicles to minimize or maximize the collision risk.” 2008. Thesis, Instituto Nacional de Pesquisas Espaciais. Accessed January 18, 2021. http://urlib.net/sid.inpe.br/[email protected]/2008/10.14.00.42.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Arraes, Álvaro de Albuquerque. “Propagation of uncertainties in the navigation of aerospace vehicles to minimize or maximize the collision risk.” 2008. Web. 18 Jan 2021.

Vancouver:

Arraes �dA. Propagation of uncertainties in the navigation of aerospace vehicles to minimize or maximize the collision risk. [Internet] [Thesis]. Instituto Nacional de Pesquisas Espaciais; 2008. [cited 2021 Jan 18]. Available from: http://urlib.net/sid.inpe.br/[email protected]/2008/10.14.00.42.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Arraes �dA. Propagation of uncertainties in the navigation of aerospace vehicles to minimize or maximize the collision risk. [Thesis]. Instituto Nacional de Pesquisas Espaciais; 2008. Available from: http://urlib.net/sid.inpe.br/[email protected]/2008/10.14.00.42

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Houston

13. Nallapu, Raviteja 1989-. Orbit Propagation via MRQ Sphere Technique.

Degree: MS, Aerospace Engineering, 2012, University of Houston

URL: http://hdl.handle.net/10657/765

► The Multi-Resolution Quadrature (MRQ) Sphere model, is a newly developed multi- resolution gravity model designed to estimate the gravity fields of arbitrary shaped space bodies,… (more)

Subjects/Keywords: Orbit Propagation; Gravity Estimation; MRQ-Sphere; Spherical harmonics; LAGEOS-II; GPS BIIA-10; Cartesian Formulation; Kepplerian elements; Gravity Potential; Orbital Mechanics; Aerospace engineering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nallapu, R. 1. (2012). Orbit Propagation via MRQ Sphere Technique. (Masters Thesis). University of Houston. Retrieved from http://hdl.handle.net/10657/765

Chicago Manual of Style (16^th Edition):

Nallapu, Raviteja 1989-. “Orbit Propagation via MRQ Sphere Technique.” 2012. Masters Thesis, University of Houston. Accessed January 18, 2021. http://hdl.handle.net/10657/765.

MLA Handbook (7^th Edition):

Nallapu, Raviteja 1989-. “Orbit Propagation via MRQ Sphere Technique.” 2012. Web. 18 Jan 2021.

Vancouver:

Nallapu R1. Orbit Propagation via MRQ Sphere Technique. [Internet] [Masters thesis]. University of Houston; 2012. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/10657/765.

Council of Science Editors:

Nallapu R1. Orbit Propagation via MRQ Sphere Technique. [Masters Thesis]. University of Houston; 2012. Available from: http://hdl.handle.net/10657/765

University of Washington

14. Awad, Armand Issam. Advances and Applications of Multiple Scale Methods in Complex Dynamical Systems.

Degree: PhD, 2017, University of Washington

URL: http://hdl.handle.net/1773/39920

► High dimensionality, numerical stiffness, and complex subsystem interactions pose fundamental challenges for the design, analysis, and certification of modern aerospace systems. This dissertation addresses these… (more)

Subjects/Keywords: Hybrid Systems; Multiple Timescales; Networked Dynamical Systems; Orbit Propagation; Reduced-Order Modelling; Singular Perturbation Theory; Aerospace engineering; Applied mathematics; Aeronautics and astronautics

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APA (6^th Edition):

Awad, A. I. (2017). Advances and Applications of Multiple Scale Methods in Complex Dynamical Systems. (Doctoral Dissertation). University of Washington. Retrieved from http://hdl.handle.net/1773/39920

Chicago Manual of Style (16^th Edition):

Awad, Armand Issam. “Advances and Applications of Multiple Scale Methods in Complex Dynamical Systems.” 2017. Doctoral Dissertation, University of Washington. Accessed January 18, 2021. http://hdl.handle.net/1773/39920.

MLA Handbook (7^th Edition):

Awad, Armand Issam. “Advances and Applications of Multiple Scale Methods in Complex Dynamical Systems.” 2017. Web. 18 Jan 2021.

Vancouver:

Awad AI. Advances and Applications of Multiple Scale Methods in Complex Dynamical Systems. [Internet] [Doctoral dissertation]. University of Washington; 2017. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1773/39920.

Council of Science Editors:

Awad AI. Advances and Applications of Multiple Scale Methods in Complex Dynamical Systems. [Doctoral Dissertation]. University of Washington; 2017. Available from: http://hdl.handle.net/1773/39920

15. Puglisi, Alessandra. Ab-initio study of x-ray spectroscopy of molecular ions : Calculs ab-initio des spectre de photoabsorption X d'ions moléculaires.

Degree: Docteur es, Chimie physique et Chimie analytique, 2017, Université Pierre et Marie Curie – Paris VI

URL: http://www.theses.fr/2017PA066257

►

La signature spectroscopique des ions moléculaires est fondamentale pour l'étude et la caractérisation de plasma en astrophysique et en laboratoire. Différentes techniques peuvent être utilisées… (more)

▼

La signature spectroscopique des ions moléculaires est fondamentale pour l'étude et la caractérisation de plasma en astrophysique et en laboratoire. Différentes techniques peuvent être utilisées pour caractériser ces plasmas parmi lesquelles la spectroscopie de photoélectrons induits par rayons X et la photo-absorption X. L'objectif de cette thèse est la simulation des spectres de photo-absorption au seuil L (2p) des ions moléculaires de silicium SiHn+ (n= 1, 2, 3) et au seuil K (1s) des ions moléculaires de l'oxygène OHn+ (n=1, 2) et du carbone CHn+ (n= 1, 2) produits lors d'une décharge plasma. Nous avons développé différents protocoles numériques permettant de calculer les spectres d'absorption aux seuils K et L en combinant des méthodes de structures électroniques et de propagation de paquet d'ondes. Les optimisations de géométrie et le calcul des seuils d'ionisation (IP) sont obtenus en utilisant la théorie de la fonctionnelle de la densité (DFT). Les effets de relaxation électronique due à la formation d'un trou en couche interne sont pris en compte au niveau SCF (convergence de la fonction d'onde électronique à N-1 électrons). Les surfaces d'énergie potentielle (PES) et les moments de transition dipolaires sont calculés à un niveau Post-HF (Interaction de configurations, CI). L'introduction explicite du couplage spin-orbite à l'aide de l'opérateur Breit-Pauli est utilisée pour l'étude du processus d'excitation au seuil L du silicium. Les spectres théoriques calculés pour les différentes molécules étudiées présentent un accord raisonnable avec les mesures expérimentales. La présence d'états électroniques métastables produits lors de la décharge plasma est discutée.

Molecular ions cover important roles in study and characterization of astrophysical and laboratory plasma. To this purposes, different spectroscopic techniques are used among which we found the X-ray photoelectron spectroscopy and the X-ray photoabsorption spectroscopy. This PhD work is focused on the calculation of X-ray photoabsorption spectra of molecular ions of silicon, carbon and oxygen XHn+ (X= Si, C, O; n= 1, 2, 3). The former is excited on the L (2p) shell while the others on the K (1s) shell produced in plasma discharged. We developed numerical protocols which permits to compute with reasonable precision the K and L-shell photoabsorption spectra combining electronic structure and nuclear wavepacket propagation methods. The optimization of the geometries and the calculation of the ionization potentials (IP) are carried out using the density functional theory (DFT). The relaxation effects due to the core hole creation are taken into account at the self-consistent field (SCF) level. The potential energy surfaces (PES) and the dipole moment transitions are computed at the post Hartree-Fock (configuration interaction, CI) level. The spin-orbit coupling effect are explicitly taken into account through the Breit-Pauli operator. The theoretical results have been compared with the experimental data and they allow the interpretation of the…

Advisors/Committee Members: Carniato, Stéphane (thesis director), Sisourat, Nicolas (thesis director).

Subjects/Keywords: Calculs ab-Initio; Interaction de configuration; Propagation du paquet d'onde; Spectroscopie à rayon-X; Couplage spin-Orbite; Ions moléculaires; Ab-initio calculations; X-ray photoabsorption spectroscopy; Spin-orbit coupling; 541.3

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APA (6^th Edition):

Puglisi, A. (2017). Ab-initio study of x-ray spectroscopy of molecular ions : Calculs ab-initio des spectre de photoabsorption X d'ions moléculaires. (Doctoral Dissertation). Université Pierre et Marie Curie – Paris VI. Retrieved from http://www.theses.fr/2017PA066257

Chicago Manual of Style (16^th Edition):

Puglisi, Alessandra. “Ab-initio study of x-ray spectroscopy of molecular ions : Calculs ab-initio des spectre de photoabsorption X d'ions moléculaires.” 2017. Doctoral Dissertation, Université Pierre et Marie Curie – Paris VI. Accessed January 18, 2021. http://www.theses.fr/2017PA066257.

MLA Handbook (7^th Edition):

Puglisi, Alessandra. “Ab-initio study of x-ray spectroscopy of molecular ions : Calculs ab-initio des spectre de photoabsorption X d'ions moléculaires.” 2017. Web. 18 Jan 2021.

Vancouver:

Puglisi A. Ab-initio study of x-ray spectroscopy of molecular ions : Calculs ab-initio des spectre de photoabsorption X d'ions moléculaires. [Internet] [Doctoral dissertation]. Université Pierre et Marie Curie – Paris VI; 2017. [cited 2021 Jan 18]. Available from: http://www.theses.fr/2017PA066257.

Council of Science Editors:

Puglisi A. Ab-initio study of x-ray spectroscopy of molecular ions : Calculs ab-initio des spectre de photoabsorption X d'ions moléculaires. [Doctoral Dissertation]. Université Pierre et Marie Curie – Paris VI; 2017. Available from: http://www.theses.fr/2017PA066257

16. Locke, Travis Cole. Further Developments in Orbit Ephemeris Derived Neutral Density.

Degree: MS, Aerospace Engineering, 2012, University of Kansas

URL: http://hdl.handle.net/1808/10617

► There are a number of non-conservative forces acting on a satellite in low Earth orbit. The one which is the most dominant and also contains… (more)

▼ There are a number of non-conservative forces acting on a satellite in low Earth orbit. The one which is the most dominant and also contains the most uncertainty is atmospheric drag. Atmospheric drag is directly proportional to atmospheric density, and the existing atmospheric density models do not accurately model the variations in atmospheric density. In this research, precision orbit ephemerides (POE) are used as input measurements in an optimal orbit determination scheme in order to estimate corrections to existing atmospheric density models. These estimated corrections improve the estimates of the drag experienced by a satellite and therefore provide an improvement in orbit determination and prediction as well as a better overall understanding of the Earth's upper atmosphere. The optimal orbit determination scheme used in this work includes using POE data as measurements in a sequential filter/smoother process using the Orbit Determination Tool Kit (ODTK) software. The POE derived density estimates are validated by comparing them with the densities derived from accelerometers on board the Challenging Minisatellite Payload (CHAMP) and the Gravity Recovery and Climate Experiment (GRACE). These accelerometer derived density data sets for both CHAMP and GRACE are available from Sean Bruinsma of the Centre National d'Etudes Spatiales (CNES). The trend in the variation of atmospheric density is compared quantitatively by calculating the cross correlation (CC) between the POE derived density values and the accelerometer derived density values while the magnitudes of the two data sets are compared by calculating the root mean square (RMS) values between the two. There are certain high frequency density variations that are observed in the accelerometer derived density data but not in the POE derived density data or any of the baseline density models. These high frequency density variations are typically small in magnitude compared to the overall day-night variation. However during certain time periods, such as when the satellite is near the terminator, the variations are on the same order of magnitude as the diurnal variations. These variations can also be especially prevalent during geomagnetic storms and near the polar cusps. One of the goals of this work is to see what affect these unmodeled high frequency variations have on orbit propagation. In order to see this effect, the orbits of CHAMP and GRACE are propagated during certain time periods using different sources of density data as input measurements (accelerometer, POE, HASDM, and Jacchia 1971). The resulting orbit propagations are all compared to the propagation using the accelerometer derived density data which is used as truth. The RMS and the maximum difference between the different propagations are analyzed in order to see what effect the unmodeled density variations have on orbit propagation. These results are also binned by solar and geomagnetic activity level. The primary input into the orbit determination scheme used to produce the POE derived density… Advisors/Committee Members: McLaughlin, Craig A. (advisor), Taghavi, Ray (cmtemember), Choi, Dongkyu (cmtemember).

Subjects/Keywords: Aerospace engineering; Engineering; Density; Ephemeris; Orbit determination; Propagation

…variations in the orbit propagation process. The effects of varying levels of noise being present… …Ranging Service LEO Low Earth Orbit Mass Spectrometer Incoherent Scatter Extending from ground… …Mass Spectrometer Incoherent Scatter NRLMSISE Extending from ground to space ODTK Orbit… …Determination Tool Kit POE Precision Orbit Ephemerides xi PSO Precision Science Orbit RMS Root… …Mean Square RSO Rapid Science Orbit SETA Satellite Electrostatic Triaxial Accelerometer…

4 more images…

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APA (6^th Edition):

Locke, T. C. (2012). Further Developments in Orbit Ephemeris Derived Neutral Density. (Masters Thesis). University of Kansas. Retrieved from http://hdl.handle.net/1808/10617

Chicago Manual of Style (16^th Edition):

Locke, Travis Cole. “Further Developments in Orbit Ephemeris Derived Neutral Density.” 2012. Masters Thesis, University of Kansas. Accessed January 18, 2021. http://hdl.handle.net/1808/10617.

MLA Handbook (7^th Edition):

Locke, Travis Cole. “Further Developments in Orbit Ephemeris Derived Neutral Density.” 2012. Web. 18 Jan 2021.

Vancouver:

Locke TC. Further Developments in Orbit Ephemeris Derived Neutral Density. [Internet] [Masters thesis]. University of Kansas; 2012. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1808/10617.

Council of Science Editors:

Locke TC. Further Developments in Orbit Ephemeris Derived Neutral Density. [Masters Thesis]. University of Kansas; 2012. Available from: http://hdl.handle.net/1808/10617

17. Dykstra, Matthew C. Single station Doppler tracking for satellite orbit prediction and propagation.

Degree: MSin Engineering, Aerospace Engineering, 2015, University of Texas – Austin

URL: http://hdl.handle.net/2152/31713

► Presently, there are two main methods of launching a cube satellite into Earth orbit. The first method is to purchase a secondary payload slot on… (more)

Subjects/Keywords: Satellite; Propagation; Doppler; Tracking; Estimation; CubeSat; Ground station; Orbit; Prediction; Scheduling; Reference frame

…orbit propagation, alone will result in errors on the order of a few kilometers to tens of… …tracking and orbit propagation. 3.1 Reference Frames There are a number of necessary reference… …Case Selection . . . . . . . 7.1.2 Orbit Prediction Results . . . . 7.2 Pass Selection and… …Nominal State Selection 7.3.3 Orbit Prediction Results… …Graphical representation of the orbital elements for a typical orbit[13]. Graphical…

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APA (6^th Edition):

Dykstra, M. C. (2015). Single station Doppler tracking for satellite orbit prediction and propagation. (Masters Thesis). University of Texas – Austin. Retrieved from http://hdl.handle.net/2152/31713

Chicago Manual of Style (16^th Edition):

Dykstra, Matthew C. “Single station Doppler tracking for satellite orbit prediction and propagation.” 2015. Masters Thesis, University of Texas – Austin. Accessed January 18, 2021. http://hdl.handle.net/2152/31713.

MLA Handbook (7^th Edition):

Dykstra, Matthew C. “Single station Doppler tracking for satellite orbit prediction and propagation.” 2015. Web. 18 Jan 2021.

Vancouver:

Dykstra MC. Single station Doppler tracking for satellite orbit prediction and propagation. [Internet] [Masters thesis]. University of Texas – Austin; 2015. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/2152/31713.

Council of Science Editors:

Dykstra MC. Single station Doppler tracking for satellite orbit prediction and propagation. [Masters Thesis]. University of Texas – Austin; 2015. Available from: http://hdl.handle.net/2152/31713

Cal Poly

18. Miura, Nicholas Z. COMPARISON AND DESIGN OF SIMPLIFIED GENERAL PERTURBATION MODELS (SGP4) AND CODE FOR NASA JOHNSON SPACE CENTER, ORBITAL DEBRIS PROGRAM OFFICE.

Degree: MS, Aerospace Engineering, 2009, Cal Poly

URL: https://digitalcommons.calpoly.edu/theses/86 ; 10.15368/theses.2009.55

► This graduate project compares legacy simplified general perturbation model (SGP4) code developed by NASA Johnson Space Center, Orbital Debris Program Office, to a recent public… (more)

Subjects/Keywords: SGP4; Orbit Propagation; Vallado; Astrodynamics; Navigation, Guidance, Control and Dynamics; Systems Engineering and Multidisciplinary Design Optimization

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APA (6^th Edition):

Miura, N. Z. (2009). COMPARISON AND DESIGN OF SIMPLIFIED GENERAL PERTURBATION MODELS (SGP4) AND CODE FOR NASA JOHNSON SPACE CENTER, ORBITAL DEBRIS PROGRAM OFFICE. (Masters Thesis). Cal Poly. Retrieved from https://digitalcommons.calpoly.edu/theses/86 ; 10.15368/theses.2009.55

Chicago Manual of Style (16^th Edition):

Miura, Nicholas Z. “COMPARISON AND DESIGN OF SIMPLIFIED GENERAL PERTURBATION MODELS (SGP4) AND CODE FOR NASA JOHNSON SPACE CENTER, ORBITAL DEBRIS PROGRAM OFFICE.” 2009. Masters Thesis, Cal Poly. Accessed January 18, 2021. https://digitalcommons.calpoly.edu/theses/86 ; 10.15368/theses.2009.55.

MLA Handbook (7^th Edition):

Miura, Nicholas Z. “COMPARISON AND DESIGN OF SIMPLIFIED GENERAL PERTURBATION MODELS (SGP4) AND CODE FOR NASA JOHNSON SPACE CENTER, ORBITAL DEBRIS PROGRAM OFFICE.” 2009. Web. 18 Jan 2021.

Vancouver:

Miura NZ. COMPARISON AND DESIGN OF SIMPLIFIED GENERAL PERTURBATION MODELS (SGP4) AND CODE FOR NASA JOHNSON SPACE CENTER, ORBITAL DEBRIS PROGRAM OFFICE. [Internet] [Masters thesis]. Cal Poly; 2009. [cited 2021 Jan 18]. Available from: https://digitalcommons.calpoly.edu/theses/86 ; 10.15368/theses.2009.55.

Council of Science Editors:

Miura NZ. COMPARISON AND DESIGN OF SIMPLIFIED GENERAL PERTURBATION MODELS (SGP4) AND CODE FOR NASA JOHNSON SPACE CENTER, ORBITAL DEBRIS PROGRAM OFFICE. [Masters Thesis]. Cal Poly; 2009. Available from: https://digitalcommons.calpoly.edu/theses/86 ; 10.15368/theses.2009.55

Indian Institute of Science

19. Nagarajan, N. Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners.

Degree: PhD, Faculty of Engineering, 2005, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/155

► Autonomous navigation is the determination of satellites position and velocity vectors onboard the satellite, using the measurements available onboard. The orbital information of a satellite… (more)

▼ Autonomous navigation is the determination of satellites position and velocity vectors onboard the satellite, using the measurements available onboard. The orbital information of a satellite needs to be obtained to support different house keeping operations such as routine tracking for health monitoring, payload data processing and annotation, orbit manoeuver planning, and prediction of intrusion in various sensors' field of view by celestial bodies like Sun, Moon etc. Determination of the satellites orbital parameters is done in a number of ways using a variety of measurements. These measurements may originate from ground based systems as range and range rate measurements, or from another satellite as in the case of GPS (Global Positioning System) and TDUSS (Tracking Data Relay Satellite Systems), or from the same satellite by using sensors like horizon sensor^ sun sensor, star tracker, landmark tracker etc. Depending upon the measurement errors, sampling rates, and adequacy of the estimation scheme, the navigation accuracy can be anywhere in the range of 10m - 10 kms in absolute location. A wide variety of tracking sensors have been proposed in the literature for autonomous navigation. They are broadly classified as (1) Satellite-satellite tracking, (2) Ground- satellite tracking, (3) fully autonomous tracking. Of the various navigation sensors, it may be cost effective to use existing onboard sensors which are well proven in space. Hence, in the current thesis, the Horizon scanner is employed as the primary navigation sensor-. It has been shown in the literature that by using horizon sensors and gyros, a high accuracy pointing of the order of .01 - .03 deg can be achieved in the case of low earth orbits. Motivated by such a fact, the current thesis deals with autonomous orbit determination using measurements from the horizon sensors with the assumption that the attitude is known to the above quoted accuracies. The horizon scanners are mounted on either side of the yaw axis in the pitch yaw plane at an angle of 70 deg with respect to the yaw axis. The Field Of View (FOV) moves about the scanner axis on a cone of 45 deg half cone angle. During each scan, the FOV generates two horizon points, one at the space-Earth entry and the other at the Earth-space exit. The horizon points, therefore, lie• on the edge of the Earth disc seen by the satellite. For a spherical earth, a minimum of three such horizon points are needed to estimate the angular radius and the center of the circular horizon disc. Since a total of four horizon points are available from a pair of scanners, they can be used to extract the satellite-earth distance and direction.These horizon points are corrupted by noise due to uncertainties in the Earth's radiation pattern, detector mechanism, the truncation and roundoff errors due to digitisation of the measurements. Owing to the finite spin rate of the scanning mechanism, the measurements are available at discrete time intervals. Thus a filtering algorithm with appropriate state dynamics becomes… Advisors/Committee Members: Bhat, M Seetharama (advisor).

Subjects/Keywords: Astronautics; Artificial Satellites - Orbits; Horizon Sensing; Horizon Sensor; Orbit Determination; Horizon Unit Vectors; Low Pass Filter (LPF); Autonomous Orbit Determination; Augmented State Filter; Orbit Propagation; Earth oblateness; Low Eccentricityn Orbits; Horizon Points; Autonomous Navigation; Extended Kalman Filter; Kalman filtering

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Nagarajan, N. (2005). Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/155

Chicago Manual of Style (16^th Edition):

Nagarajan, N. “Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners.” 2005. Doctoral Dissertation, Indian Institute of Science. Accessed January 18, 2021. http://etd.iisc.ac.in/handle/2005/155.

MLA Handbook (7^th Edition):

Nagarajan, N. “Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners.” 2005. Web. 18 Jan 2021.

Vancouver:

Nagarajan N. Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2005. [cited 2021 Jan 18]. Available from: http://etd.iisc.ac.in/handle/2005/155.

Council of Science Editors:

Nagarajan N. Autonomous Orbit Estimation For Near Earth Satellites Using Horizon Scanners. [Doctoral Dissertation]. Indian Institute of Science; 2005. Available from: http://etd.iisc.ac.in/handle/2005/155

20. Leary, Cody Collin, 1981-. Measurement and control of transverse photonic degrees of freedom via parity sorting and spin-orbit interaction.

Degree: 2010, University of Oregon

URL: http://hdl.handle.net/1794/10910

► In this dissertation, several new methods for the measurement and control of transverse photonic degrees of freedom are developed. We demonstrate a mode sorter for… (more)

▼ In this dissertation, several new methods for the measurement and control of transverse photonic degrees of freedom are developed. We demonstrate a mode sorter for two-dimensional (2-D) parity of transverse spatial states of light based on an out-of-plane Sagnac interferometer. The first experimental 2-D parity sorting measurements of Hermite-Gauss transverse spatial modes are presented. Due to the inherent phase stability of this type of interferometer, it provides a promising tool for the manipulation of higher order transverse spatial modes for the purposes of quantum information processing. We propose two such applications: the production of both spatial-mode entangled Bell states and heralded single photons, tailored to cover the entire Poincaré sphere of first-order transverse modes. In addition to the aforementioned transverse spatial manipulation based on free-space parity sorting, we introduce several more such techniques involving photons propagating in optical fibers. We show that when a photon propagates in a cylindrically symmetric waveguide, its spin angular momentum and its orbital angular momentum (OAM) interact. This spin-orbit interaction (SOI) leads to the prediction of several novel rotational effects: the spatial or time evolution of the photonic polarization vector is controlled by its OAM quantum number or, conversely, its spatial wave function is controlled by its spin. We demonstrate how these phenomena can be used to reversibly transfer entanglement between the spin and OAM degrees of freedom of two-particle states. In order to provide a deeper insight into the cause of the SOI for photons, we also investigate an analogous interaction for electrons in a cylindrical waveguide and find that each of the SOI effects mentioned above remain manifest for the electron case. We show that the SOI dynamics are quantitatively described by a single expression applying to both electrons and photons and explain their common origin in terms of a universal geometric phase associated with the interplay between either particle's spin and OAM. This implies that these SOI-based effects occur for any particle with spin and thereby exist independently of whether or not the particle has mass, charge, or magnetic moment.

Subjects/Keywords: Degrees of freedom; Spin orbit interactions; Parity sorting; Geometric phases; Transverse spacial modes; Photon propagation; Quantum physics; Optics; Particle physics

…147 ... . . . . . . . . . . . . .. Spin-Orbit Correction to the Propagation Constant… …Spin-Orbit Wave Packet in a Weakly Inhomogeneous Medium 18 Geometric Phase of a General… …a Spin-Orbit Wave Packet… …Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 107 110 V. SPIN-ORBIT… …113 Spin-Orbit Wave Equations…

10 more images…

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APA (6^th Edition):

Leary, Cody Collin, 1. (2010). Measurement and control of transverse photonic degrees of freedom via parity sorting and spin-orbit interaction. (Thesis). University of Oregon. Retrieved from http://hdl.handle.net/1794/10910

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Leary, Cody Collin, 1981-. “Measurement and control of transverse photonic degrees of freedom via parity sorting and spin-orbit interaction.” 2010. Thesis, University of Oregon. Accessed January 18, 2021. http://hdl.handle.net/1794/10910.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Leary, Cody Collin, 1981-. “Measurement and control of transverse photonic degrees of freedom via parity sorting and spin-orbit interaction.” 2010. Web. 18 Jan 2021.

Vancouver:

Leary, Cody Collin 1. Measurement and control of transverse photonic degrees of freedom via parity sorting and spin-orbit interaction. [Internet] [Thesis]. University of Oregon; 2010. [cited 2021 Jan 18]. Available from: http://hdl.handle.net/1794/10910.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Leary, Cody Collin 1. Measurement and control of transverse photonic degrees of freedom via parity sorting and spin-orbit interaction. [Thesis]. University of Oregon; 2010. Available from: http://hdl.handle.net/1794/10910

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Pontifical Catholic University of Rio de Janeiro

21. MARTA PUDWELL CHAVES DE ALMEIDA. [en] PROPAGATION EFFECTS IN LOW EARTH ORBIT SATTELITE LINKS.

Degree: 2003, Pontifical Catholic University of Rio de Janeiro

URL: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4245

►

[pt] O efeito da atenuação por chuvas em enlaces satélites que operam em frequências acima de 10 GHz é decisivo no cálculo de desempenho do… (more)

▼

[pt] O efeito da atenuação por chuvas em enlaces satélites que operam em frequências acima de 10 GHz é decisivo no cálculo de desempenho do sistema. A evolução da tecnologia dos sistemas satélite e a necessidade de expansão dos serviços de comunicações móveis pessoais levaram ao uso de sistemas de comunicação com satélites de órbita baixa. Estes sistemas são particularmente interessantes para o oferecimento destes serviços por suas características de pequeno atraso de propagação e uso de potência de transmissão mais baixas que os sistemas geoestacionários. Satélites em órbita baixas (LEO) operam em altitudes de cerca de 1000km e possuem movimento em relação à estação terrena. Esta característica de mobilidade traz novas questões sobre o comportamento da atenuação por chuvas, em particular a necessidade de um modelo de previsão de atenuação para estes enlaces com ângulo de elevação variante no tempo. Neste trabalho um modelo para a previsão de atenuação em enlaces com ângulo de elevação fixo, mais preciso do que os existentes na literatura técnica, foi desenvolvido como primeiro passo para o tratamento do problema de enlaces com ângulo de elevação variável. A seguir foi feita uma simulação de medidas em enlaces LEO a partir do banco de dados de medidas de atenuação em enlaces fixos no Brasil, considerando um modelo de constelação de satélites. Foi implementado um método geral que utiliza o histograma dos ângulos de elevação do satélite como ponderação da distribuição cumulativa de atenuação em cada ângulo. O método foi testado contra os resultados obtidos com simulações para a constelação Globalstar sendo obtida muito boa concordância entre o modelo de predição desenvolvido e a simulação.

[en] Rain attenuation is the most important propagation effect to be taken into account in the performance calculation for satellite systems operation at frequencies above 10 GHz. The technological evolution of such systems and the need for personal communication systems with global coverage lead to the use of low earth orbit communication systems, that not only have shorter propagation delays but also allow the use of lower transmission power than the traditional geostationary systems. Low earth orbit (LEO) satellites have altitudes around 1.000 Km and are in motion relatively to the earth stations. This mobility requires a new approach to the problem of rain attenuation prediction, particularly the need for a prediction model that takes into account the elevation angle variability. In this work, an improved rain attenuation prediction method for the geostationary case has been developed as a starting point for the analysis of the nongeostationary case. Then, the rain attenuation in the a LEO system has been simulated using measured data from fixed system systems and the satellite constellation model. A general method for slant path rain attenuation prediction considering variable elevation angles is proposed. The method uses the histogram of the elevation angles to weight the distributions obtained for fixed elevation. The…

Advisors/Committee Members: LUIZ ALENCAR REIS DA SILVA MELLO.

Subjects/Keywords: [pt] PROPAGACAO DE ONDAS; [en] WAVE PROPAGATION; [pt] ATENUACAO POR CHUVAS; [en] RAIN ATTENUATION; [pt] ENLACES SATELITE; [en] SATELLITE LINKS; [pt] ORBITA DE SATELITES GEOESTACIONARIOS; [en] GEOESTATIONARY SATELLITE ORBIT; [pt] PRECIPITACAO; [en] PRECIPITATION; [pt] SISTEMA DE ORBITA BAIXA; [en] LOW ORBIT SYSTEM

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

ALMEIDA, M. P. C. D. (2003). [en] PROPAGATION EFFECTS IN LOW EARTH ORBIT SATTELITE LINKS. (Thesis). Pontifical Catholic University of Rio de Janeiro. Retrieved from http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4245

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

ALMEIDA, MARTA PUDWELL CHAVES DE. “[en] PROPAGATION EFFECTS IN LOW EARTH ORBIT SATTELITE LINKS.” 2003. Thesis, Pontifical Catholic University of Rio de Janeiro. Accessed January 18, 2021. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4245.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

ALMEIDA, MARTA PUDWELL CHAVES DE. “[en] PROPAGATION EFFECTS IN LOW EARTH ORBIT SATTELITE LINKS.” 2003. Web. 18 Jan 2021.

Vancouver:

ALMEIDA MPCD. [en] PROPAGATION EFFECTS IN LOW EARTH ORBIT SATTELITE LINKS. [Internet] [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2003. [cited 2021 Jan 18]. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4245.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

ALMEIDA MPCD. [en] PROPAGATION EFFECTS IN LOW EARTH ORBIT SATTELITE LINKS. [Thesis]. Pontifical Catholic University of Rio de Janeiro; 2003. Available from: http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4245

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Indian Institute of Science

22. Anilkumar, A K. NEW PERSPECTIVES FOR ANALYZING THE BREAKUP, ENVIRONMENT, EVOLUTION, COLLISION RISK AND REENTRY OF SPACE DEBRIS OBJECTS.

Degree: PhD, Faculty of Engineering, 2005, Indian Institute of Science

URL: http://etd.iisc.ac.in/handle/2005/80

► In the space surrounding the earth there are two major regions where orbital debris causes concern. They are the Low Earth Orbits (LEO) up to… (more)

▼ In the space surrounding the earth there are two major regions where orbital debris causes concern. They are the Low Earth Orbits (LEO) up to about 2000 km, and Geosynchronous Orbits (GEO) at an altitude of around 36000 km. The impact of the debris accumulations are in principle the same in the two regions; nevertheless they require different approaches and solutions, due to the fact that the perturbations in the orbital decay due to atmospheric drag effects predominates in LEO, gravitational forces including earth’s oblateness and luni solar effects dominating in GEO are different in these two regions. In LEO it is generally known that the debris population dominates even the natural meteoroid population for object sizes 1 mm and larger. This thesis focuses the study mainly in the LEO region. Since the first satellite breakup in 1961 up to 01 January 2003 more than 180 spacecraft and rocket bodies have been known to fragment in orbit. The resulting debris fragments constitute nearly 40% of the 9000 or more of the presently tracked and catalogued objects by USSPACECOM. The catalogued fragment count does not include the much more numerous fragments, which are too small to be detected from ground. Hence in order to describe the trackable orbital debris environment, it is important to develop mathematical models to simulate the trackable fragments and later expand it to untrackable objects. Apart from the need to better characterize the orbital debris environment down to sub millimeter particles, there is also a pressing necessity of simulation tools able to model in a realistic way the long term evolution of space debris, to highlight areas, which require further investigations, and to study the actual mitigation effects of space policy measures. The present thesis has provided newer perspectives for five major issues in space debris modeling studies. The issues are (i) breakup modeling, (ii) environment modeling, (iii) evolution of the debris environment, (iv) collision probability analysis and (v) reentry prediction. The Chapter 1 briefly describes an overview of space debris environment and the issues associated with the growing space debris populations. A literature survey of important earlier work carried out regarding the above mentioned five issues are provided in the Chapter 2. The new contributions of the thesis commence from Chapter 3. The Chapter 3 proposes a new breakup model to simulate the creation of debris objects by explosion in LEO named “A Semi Stochastic Environment Modeling for Breakup in LEO” (ASSEMBLE). This model is based on a study of the characteristics of the fragments from on orbit breakups as provided in the TLE sets for the INDIAN PSLV-TES mission spent upper stage breakup. It turned out that based on the physical mechanisms in the breakup process the apogee, perigee heights (limited by the breakup altitude) closely fit suitable Laplace distributions and the eccentricity follows a lognormal distribution. The location parameters of these depend on the orbit of the parent body at the time of… Advisors/Committee Members: Ananthasayanam, M R (advisor), Rao, P V Subba (advisor).

Subjects/Keywords: Aerospace Engineering; Space Debris Modelling; On Orbit Breakup; Debris Clouds; Evolution; Collision Risk; Re entry; Kalman Filter; ASSEMBLE Model; SIMPLE model; Orbital Elements; Propagation; Collision probability; Semi major axis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Anilkumar, A. K. (2005). NEW PERSPECTIVES FOR ANALYZING THE BREAKUP, ENVIRONMENT, EVOLUTION, COLLISION RISK AND REENTRY OF SPACE DEBRIS OBJECTS. (Doctoral Dissertation). Indian Institute of Science. Retrieved from http://etd.iisc.ac.in/handle/2005/80

Chicago Manual of Style (16^th Edition):

Anilkumar, A K. “NEW PERSPECTIVES FOR ANALYZING THE BREAKUP, ENVIRONMENT, EVOLUTION, COLLISION RISK AND REENTRY OF SPACE DEBRIS OBJECTS.” 2005. Doctoral Dissertation, Indian Institute of Science. Accessed January 18, 2021. http://etd.iisc.ac.in/handle/2005/80.

MLA Handbook (7^th Edition):

Anilkumar, A K. “NEW PERSPECTIVES FOR ANALYZING THE BREAKUP, ENVIRONMENT, EVOLUTION, COLLISION RISK AND REENTRY OF SPACE DEBRIS OBJECTS.” 2005. Web. 18 Jan 2021.

Vancouver:

Anilkumar AK. NEW PERSPECTIVES FOR ANALYZING THE BREAKUP, ENVIRONMENT, EVOLUTION, COLLISION RISK AND REENTRY OF SPACE DEBRIS OBJECTS. [Internet] [Doctoral dissertation]. Indian Institute of Science; 2005. [cited 2021 Jan 18]. Available from: http://etd.iisc.ac.in/handle/2005/80.

Council of Science Editors:

Anilkumar AK. NEW PERSPECTIVES FOR ANALYZING THE BREAKUP, ENVIRONMENT, EVOLUTION, COLLISION RISK AND REENTRY OF SPACE DEBRIS OBJECTS. [Doctoral Dissertation]. Indian Institute of Science; 2005. Available from: http://etd.iisc.ac.in/handle/2005/80

Open Access Theses and Dissertations