Dr. Khanh D. Pham
Title: Practical Challenges and Solutions for Satellite Communications
Using Multiple Bands and Orbits
Abstract
In this keynote, Dr. Pham will cover practical challenges and solutions related to communications that do not depend on a fixed path, using multiple commercial space internet networks in different orbits. The discussion will include using Low-Earth-Orbit (LEO), Medium-Earth-Orbit (MEO), and Geosynchronous-Earth-Orbit (GEO) satellite constellations to improve connectivity in difficult environments. Dr. Pham will outline progress in flexible, intelligent, and resilient communication services that work across multiple frequency bands and orbits. These advancements are supported by machine learning-based satellite transponder linearization, comprehensive radio environment awareness, global network access terminals, and multi-path named data networking.
Effective and affordable use of commercial space internet constellations depends on maximizing satellite transponder power efficiency and spectrum resources. This involves leveraging existing satellite hub configurations and user terminals to provide low-cost, adaptive solutions that address persistent noise and interference. Employing both physical model-based predistortion and machine learning techniques can improve high power amplifier linearization.
Moreover, to fully benefit from emerging constellations, it is important to neutralize radio frequency interference and maintain a robust radio environment. This requires near real-time situational awareness of both persistent and transient interference, as well as understanding losses in uplink and downlink segments and power losses across the satellite transponder.
Implementations that enable rapid introduction of new commercial space internet vendors after terminal hardware deployment are also of interest. Using common hardware elements to communicate with both commercial space internet constellations and government-owned communications systems may provide greater flexibility in communication paths while minimizing the deployment of constellation-specific hardware. Solutions such as global access terminals that connect to multiple constellations and distribute traffic between them may help understand broadband bonding methods through commercial space internet providers for enhanced global coverage, network throughput, and robustness.
Finally, seamless aggregation of IP-based terrestrial and non-terrestrial networks, including LEO, MEO, and GEO constellations, enables simultaneous access to multiple networks or rapid switching between them. Multi-path overlay networking using Named Data Networking supports integration with existing underlay IP-based networks, improving network delay, throughput, security, and resilience.
Biography
Dr. Khanh Pham is a supervisory principal aerospace engineer and Section Chief for Satellite Navigation Technology at the Air Force Research Laboratory-Space Vehicles Directorate at Kirtland Air Force Base, New Mexico, USA. He received his Bachelor and Master of Science degrees in Electrical Engineering from the University of Nebraska-Lincoln in 1997 and 1998, and his Ph.D. in Electrical Engineering from the University of Notre Dame in 2004. Dr. Pham is currently an Adjunct Research Professor at the University of New Mexico, Electrical and Computer Engineering Department, researching stochastic controls and game theory. He is a Fellow of the Institute of Electrical and Electronics Engineers (IEEE), the American Institute of Aeronautics and Astronautics (AIAA), the Society of Photo-Optical and Instrumentation Engineers (SPIE), the Air Force Research Laboratory (AFRL), the Institution of Engineering and Technology (IET), the National Academy of Inventors (NAI), the Royal Aeronautical Society (RAeS), the American Astronautical Society (AAS), the Royal Astronomical Society (RAS), the International Association for the Advancement of Space Safety (IAASS), and the Asia-Pacific Artificial Intelligence Association (AAIA). He is also an Associate Fellow of the Royal Institute of Navigation (RIN). Dr. Pham served as Senior Editor for Intelligent Systems of the IEEE Transactions on Aerospace and Electronics Systems from 2017 to 2022. His research interests include statistical optimal control, decision analysis of adversarial systems, resilient navigation and authentication, dynamic game decision optimization, security of cyber-physical systems, satellite cognitive radios, digital beam forming, and control and coordination of large-scale dynamical systems. He has compiled over 300 scientific papers, 30 book chapters, and 46 journal articles. His research monographs include “Resilient Controls for Ordering Uncertain Prospects: Change and Response” (ISBN 978-3-319-08704-7, Springer 2014) and “LinearQuadratic Controls in Risk-Averse Decision Making: Performance-Measure Statistics and Control Decision Optimization” (ISBN 978-1-4614-5078-8, Springer 2012). He holds 54 US patents.
