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this trend will continue as we learn more about the ionosphere
and advance GNSS receiver technologies. In the near future,
multifrequency and multiconstellation signals will enable algorithm development opportunities to further exploit diversities
in spectral and spatial domains during scintillation. The continued advancement in computing and processing technologies
will help to transform the more computationally intense optimization algorithms into real-time systems. The growing density and coverage of various GNSS ground- and space-based
augmentation networks and the improvement in measurement
update and quality will provide opportunities to generate more
timely and accurate ionospheric decorrelation and scintillation
event coverage, thereby leading to potential nowcasting and
forecasting capabilities.

Jiyun Lee was supported by the Space Core Technology Development Program of the National Research Foundation (NRF)
funded by the Ministry of Science, ICT, and Future Planning
(NRF-2014M1A3A3A02034937). Hee-Seung Moon and Jiwon
Seo were supported by the Ministry of Science, ICT, and Future
Planning (MSIP), South Korea, under the "ICT Consilience
Creative Program" (IITP-2017-2017-0-01015) supervised by the
Institute for Information and Communications Technology Promotion. Jiwon Seo is the corresponding author of this article.

aerospace engineering. Her research interests include safetycritical global navigation satellite system (GNSS) applications, space weather forecasting for GNSS applications, and
safety assurance of multisensor integrated navigation systems.
Hee-Seung Moon (hs.moon@yonsei.ac.kr) received a B.S.
degree in integrated technology from Yonsei University,
Incheon, South Korea, in 2015, where he is currently pursuing
his Ph.D. degree in integrated technology. His research interests include global navigation satellite systems, haptics, and
human-robot interaction. He is a recipient of the Graduate
Fellowship from the IT Consilience Creative Program supported by the Ministry of Science, ICT, and Future Planning,
South Korea.
Jiwon Seo (jiwon.seo@yonsei.ac.kr) received a B.S. degree in
mechanical engineering (division of aerospace engineering)
in 2002 from the Korea Advanced Institute of Science and
Technology, Daejeon, South Korea. He received an M.S. degree
in aeronautics/astronautics in 2004, an M.S. degree in electrical
engineering in 2008, and a Ph.D. degree in aeronautics/astronautics in 2010 from Stanford University, California. He is currently
an assistant professor with the School of Integrated Technology
and the Yonsei Institute of Convergence Technology, Yonsei
University, Incheon, South Korea. He is also a member of the
International Advisory Council of the Resilient Navigation and
Timing Foundation, Alexandria, Virginia.

Authors

References

Acknowledgments

Jiyun Lee (jiyunlee@kaist.ac.kr) received a B.S. degree in
astronomy and atmospheric science in 1997 from Yonsei
University in Seoul, South Korea, an M.S. degree in aerospace
engineering sciences in 1999 from the University of Colorado
Boulder, and a Ph.D. degree in aeronautics and astronautics
from Stanford University, California, in 2005. She is an associate professor in the Department of Aerospace Engineering at
the Korea Advanced Institute of Science and Technology in
Daejeon, South Korea. She has published more than 80
research papers in the field of global navigation satellite system applications, multisensor navigation, safety-critical systems, atmospheric science, and remote sensing.
Y.T. Jade Morton (Jade.Morton@colorado.edu) is an aerospace engineering sciences professor at the University of
Colorado Boulder. She received a B.S. degree in physics from
Nanjing University, China, in 1983 and a Ph.D. degree from
Pennsylvania State University, University Park, in 1991.
Previously, she was an electrical engineering professor at
Colorado State University and Miami University, Florida. Her
research interests are satellite navigation technologies and remote
sensing applications. She is the Institute of Navigation (ION)
executive vice president, the technical editor for navigation systems of IEEE Transactions on Aerospace and Electronics
Systems, a recipient of the ION Thomas L. Thurlow Award and
Samuel Burka Award, and a Fellow of the IEEE and ION.
Jinsil Lee (jinsil@kaist.ac.kr) received a B.S. degree in
civil and environmental engineering from the Korea Advanced
Institute of Science and Technology, Daejeon, South Korea, in
2012, where she is currently pursuing her Ph.D. degree in

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