A5011623613- GNSS positioning and interference
- Geophysics and Gravity Measurements
- Inertial Sensor and Navigation
- Advanced Frequency and Time Standards
- Robotics and Sensor-Based Localization
- Indoor and Outdoor Localization Technologies
- Advanced Image and Video Retrieval Techniques
- Ionosphere and magnetosphere dynamics
- Mobile Agent-Based Network Management
- Target Tracking and Data Fusion in Sensor Networks
- Satellite Communication Systems
- Network Time Synchronization Technologies
- Cardiovascular Syncope and Autonomic Disorders
- Distributed systems and fault tolerance
- Geophysics and Sensor Technology
- Spacecraft Design and Technology
- Robotic Path Planning Algorithms
- Astro and Planetary Science
- Space Satellite Systems and Control
- Scientific Measurement and Uncertainty Evaluation
- Advanced Vision and Imaging
- Advanced Fiber Laser Technologies
- Underwater Vehicles and Communication Systems
- Fault Detection and Control Systems
- Software System Performance and Reliability
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2018-2023
Technical University of Munich
2012-2022
University of Trento
2020-2022
ETH Zurich
2022
The University of Melbourne
2022
University of Fribourg
2022
Institute of Navigation
2019-2020
Delft University of Technology
2008-2020
Ludwig-Maximilians-Universität München
2013
On August 22, 2014, the satellites GSAT-0201 and GSAT-0202 of European GNSS Galileo were unintentionally launched into eccentric orbits. Unexpectedly, this has become a fortunate scientific opportunity since onboard hydrogen masers allow for sensitive test redshift predicted by theory general relativity. In present Letter we describe an analysis approximately three years data from these including different clocks. For one determine parameter quantifying potential violation combined effects...
Global navigation satellite system (GNSS) ambiguity resolution is the process of resolving unknown cycle ambiguities carrier phase data as integers. The sole purpose to use integer constraints a means improving significantly on precision remaining GNSS model parameters. In this contribution, we consider problem for attitude determination. We analyse performance new method As it will be shown, provides numerically efficient, highly reliable and robust solution nonlinearly constrained...
Global Navigation Satellite System (GNSS) is a valuable technology for large number of maritime applications. Other than providing the absolute positioning service, it aids many demanding applications, such as precise docking, formation surface craft, autonomous vehicles, sinkage monitoring, etc. GNSS carrier-phase-based algorithms provide high-precision solutions, but an integer cycles inherent to observed signal have be resolved. A newly developed carrier-phase ambiguity resolution method...
Carrier phase integer ambiguity resolution is the key to fast and high-precision GNSS positioning navigation. It process of resolving unknown cycle ambiguities double-differenced carrier data as integers. The popular LAMBDA method an efficient algorithm that used resolve ambiguities, known maximize success rate. has been modified be applicable attitude determination problems, where all nonlinear constraints have fully integrated into objective function corresponding search. tested processing...
Accurate, robust and reliable positioning timing has become crucial for a wide spectrum of applications. New technologies will further improve the services offered by Global Navigation Satellite Systems (GNSSs). Optical are promising candidates to achieve significant improvements in terms accuracy, robustness reliability GNSSs near future. First foremost, optical inter-satellite links (OISLs) clock show enormous potential future applications at core next generation GNSS architectures. Both...
A potential development in future Global Navigation Satellite Systems is the use of optical inter-satellite links and frequency references to provide enhanced navigation timing services. These services are chiefly dependent on tight synchronization signals broadcast by constellation's satellites, which turn depend stability their references, capabilities time transfer schemes, accuracy system's orbit determination. This paper discusses recent efforts design orbits for a constellation...
Traditionally the relative positioning and attitude determination problem are treated as independent. In this contribution we will investigate possibilities of using multiantenna (i.e., triple quadruple) data, not only for but also positioning. The methods developed rigorous have additional advantage that they improve ambiguity resolution on unconstrained baseline(s) overall success rate between a number antennas.
In this contribution a new approach to ambiguity resolution for Global Navigation Satellite System (GNSS)-based attitude estimation applications is discussed and tested. This enhances the observation model by means of additional linear constraints. These constraints are implicitly derived applying an affine transformation unknown real-valued parameters, largely aid integer through improved float estimation. The method characterized lower computational complexity than rigorous...
A bi-directional optical link is established over 10.45 km to perform Two-Way Frequency and Time Transfer (TWFT, TWTT) validate the system design for Lower Earth Orbit (LEO) ground links through atmospheric channel. Binary phase shift keying with a homodyne reception scheme used recover carrier frequency. The time transfer enabled by correlation dynamic tracking of 25.6 Gcps transmission spread-sequence locally generated reference sequence. An additional data 50 Mbps performed on same...