caa a22 4500 606162321 CHVBK 20210128100638.0 cr unu---uuuuu 210128e20150701xx s 000 0 eng 10.1007/s10291-014-0404-6 doi (NATIONALLICENCE)springer-10.1007/s10291-014-0404-6 GBAS ionospheric threat model assessment for category I operation in the Korean region [Elektronische Daten] [Minchan Kim, Yunjung Choi, Hyang-Sig Jun, Jiyun Lee] During extreme ionospheric storms, anomalous ionospheric gradients can become high enough to affect Global Navigation Satellite Systems (GNSS) Ground-Based Augmentation Systems (GBAS) and to threaten the safety of GBAS users. An ionospheric anomaly threat model for the Conterminous United States (CONUS) was developed based on extreme ionospheric gradients observed in CONUS during the last solar maximum period (2000-2004). However, in order to understand and mitigate ionosphere threats occurring in different geographical regions, ionospheric anomaly threat models have to be established for the relevant regions. To allow the certification of a GBAS ground facility in South Korea, a Korean ionospheric anomaly threat model must be determined. We describe the method of data analysis that was used to estimate ionospheric spatial gradients. Estimates of anomalous gradients in the Korean region were used to define and build an ionospheric anomaly threat model for this region. All gradient estimates obtained using Korean GNSS reference network data for potential ionospheric storm dates from 2000 to 2004 were included in this threat space. The maximum spatial gradient within this threat space is 160mm of delay per km of user separation, which falls well within the bounds of the current ionospheric threat model for CONUS. We also provide a detailed examination of the two largest ionospheric spatial gradient events observed in this study, which occurred on November 10, 2004, and November 6, 2001, respectively. Springer-Verlag Berlin Heidelberg, 2014 GNSS nationallicence GBAS nationallicence LAAS nationallicence Ionospheric threat model nationallicence Kim Minchan Division of Aerospace Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, 305-701, Daejeon, Republic of Korea aut Choi Yunjung Korea Aerospace Research Institute, 169-84 Gwahak-ro, 305-806, Daejeon, Republic of Korea aut Jun Hyang-Sig Korea Aerospace Research Institute, 169-84 Gwahak-ro, 305-806, Daejeon, Republic of Korea aut Lee Jiyun Division of Aerospace Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, 305-701, Daejeon, Republic of Korea aut GPS Solutions Springer Berlin Heidelberg 19/3(2015-07-01), 443-456 1080-5370 19:3<443 2015 19 10291 https://doi.org/10.1007/s10291-014-0404-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10291-014-0404-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kim Minchan Division of Aerospace Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, 305-701, Daejeon, Republic of Korea aut NATIONALLICENCE 700 1- Choi Yunjung Korea Aerospace Research Institute, 169-84 Gwahak-ro, 305-806, Daejeon, Republic of Korea aut NATIONALLICENCE 700 1- Jun Hyang-Sig Korea Aerospace Research Institute, 169-84 Gwahak-ro, 305-806, Daejeon, Republic of Korea aut NATIONALLICENCE 700 1- Lee Jiyun Division of Aerospace Engineering, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, 305-701, Daejeon, Republic of Korea aut NATIONALLICENCE 773 0- GPS Solutions Springer Berlin Heidelberg 19/3(2015-07-01), 443-456 1080-5370 19:3<443 2015 19 10291