Matches in SemOpenAlex for { <https://semopenalex.org/work/W2601549047> ?p ?o ?g. }
- W2601549047 endingPage "2848" @default.
- W2601549047 startingPage "2840" @default.
- W2601549047 abstract "The Local Area Augmentation System (LAAS) provides differential GPS corrections for Category I precision approach to aviation users within tens of kilometers of the LAAS Ground Facility (LGF). To ensure integrity, any circumstance that may lead to hazardously misleading information (HMI) being transmitted to the user must be identified. If the probability of the situation exceeds the allocated integrity risk, its maximum user errors must be bounded by one or more user-computed protection levels. Over short baselines, the differential ionosphere error between a user and LGF can pose one such threat. This work examines how the spatial rate of change of the ionosphere over baselines of tens of kilometers can be modeled to provide insight into hazardous conditions. We develop a static spatial model of the ionosphere based on a technique developed for understanding the impact on WAAS of the 31 October 2003 localized nighttime ionosphere enhancement. In this work we apply the method to the 20 November 2003 ionosphere storm, a day on which GPS observations of the disturbed ionosphere were previously used to populate the space of possible ionosphere threats to LAAS users. This 3-D model assigns vertical profiles to latitude and longitude regions. The horizontal “enhancement” and “background” ionosphere regions are identified based on measurements made by the Continuously Operating Reference Stations (CORS). Since observations of vertical density variations are limited with GPS receivers on the ground, space-based GPS data from on board one of the GRACE satellites passing through the disturbed ionosphere around 19:40 UT is used to test a range of vertical electron density profiles. The 500 km orbital altitude of the GRACE satellites effectively limits the contribution to the total electron content of the topside and plasmasphere. After finding the electron density model that minimizes the mean squared error, we then integrate through the lines of sight of a set of CORS receivers located in Ohio and separated by baselines as short as 50-75 km. Pairs of these stations mimic user-LGF pairs and were used in the literature to estimate the possible spatial decorrelation over LAAS baselines. We integrate through the CORS lines of sight (LOS) to compute the differential ionosphere over tens-of-kilometer baselines. We find that a 3-D static model of the ionosphere cannot reproduce the 350-400 mm/km spatial rates of change in ionosphere error that have been verified with data. However, we find that allowing the ionosphere anomaly to sweep westward at 300 m/s, as has been estimated from data, can in fact reproduce rates of change between neighboring CORS stations on the order of 400 mm/km. Further refinements are needed to optimize the model-predicted delay over the three-hour timespan of the terrestrial observations, though the gross features are similar. This work confirms that the relative velocity of the ionosphere structure and the lines of sight are an important factor in apparent gradients in the ionosphere and also helps to further validate the estimates made from the CORS observations of short baseline spatial rates of change in ionosphere delay." @default.
- W2601549047 created "2017-04-07" @default.
- W2601549047 creator A5032219871 @default.
- W2601549047 creator A5039196795 @default.
- W2601549047 creator A5066683993 @default.
- W2601549047 creator A5072997498 @default.
- W2601549047 date "2007-09-28" @default.
- W2601549047 modified "2023-09-26" @default.
- W2601549047 title "Modeling the 20 November 2003 Iionosphere Storm with GRACE" @default.
- W2601549047 cites W1599691811 @default.
- W2601549047 cites W1614001277 @default.
- W2601549047 cites W1953539168 @default.
- W2601549047 cites W2036818080 @default.
- W2601549047 cites W2068680713 @default.
- W2601549047 cites W2081932370 @default.
- W2601549047 cites W2131053030 @default.
- W2601549047 cites W2149844370 @default.
- W2601549047 cites W2184486707 @default.
- W2601549047 cites W2303979488 @default.
- W2601549047 cites W2587813407 @default.
- W2601549047 cites W2606381105 @default.
- W2601549047 cites W2615317921 @default.
- W2601549047 cites W2616770436 @default.
- W2601549047 cites W3036552716 @default.
- W2601549047 cites W607416012 @default.
- W2601549047 hasPublicationYear "2007" @default.
- W2601549047 type Work @default.
- W2601549047 sameAs 2601549047 @default.
- W2601549047 citedByCount "0" @default.
- W2601549047 crossrefType "journal-article" @default.
- W2601549047 hasAuthorship W2601549047A5032219871 @default.
- W2601549047 hasAuthorship W2601549047A5039196795 @default.
- W2601549047 hasAuthorship W2601549047A5066683993 @default.
- W2601549047 hasAuthorship W2601549047A5072997498 @default.
- W2601549047 hasConcept C105306849 @default.
- W2601549047 hasConcept C116403925 @default.
- W2601549047 hasConcept C122523270 @default.
- W2601549047 hasConcept C123046963 @default.
- W2601549047 hasConcept C127313418 @default.
- W2601549047 hasConcept C127413603 @default.
- W2601549047 hasConcept C13280743 @default.
- W2601549047 hasConcept C136764020 @default.
- W2601549047 hasConcept C146978453 @default.
- W2601549047 hasConcept C153294291 @default.
- W2601549047 hasConcept C19269812 @default.
- W2601549047 hasConcept C205649164 @default.
- W2601549047 hasConcept C22041718 @default.
- W2601549047 hasConcept C2777928014 @default.
- W2601549047 hasConcept C2780554747 @default.
- W2601549047 hasConcept C39432304 @default.
- W2601549047 hasConcept C41008148 @default.
- W2601549047 hasConcept C60229501 @default.
- W2601549047 hasConcept C62649853 @default.
- W2601549047 hasConcept C76155785 @default.
- W2601549047 hasConcept C8058405 @default.
- W2601549047 hasConceptScore W2601549047C105306849 @default.
- W2601549047 hasConceptScore W2601549047C116403925 @default.
- W2601549047 hasConceptScore W2601549047C122523270 @default.
- W2601549047 hasConceptScore W2601549047C123046963 @default.
- W2601549047 hasConceptScore W2601549047C127313418 @default.
- W2601549047 hasConceptScore W2601549047C127413603 @default.
- W2601549047 hasConceptScore W2601549047C13280743 @default.
- W2601549047 hasConceptScore W2601549047C136764020 @default.
- W2601549047 hasConceptScore W2601549047C146978453 @default.
- W2601549047 hasConceptScore W2601549047C153294291 @default.
- W2601549047 hasConceptScore W2601549047C19269812 @default.
- W2601549047 hasConceptScore W2601549047C205649164 @default.
- W2601549047 hasConceptScore W2601549047C22041718 @default.
- W2601549047 hasConceptScore W2601549047C2777928014 @default.
- W2601549047 hasConceptScore W2601549047C2780554747 @default.
- W2601549047 hasConceptScore W2601549047C39432304 @default.
- W2601549047 hasConceptScore W2601549047C41008148 @default.
- W2601549047 hasConceptScore W2601549047C60229501 @default.
- W2601549047 hasConceptScore W2601549047C62649853 @default.
- W2601549047 hasConceptScore W2601549047C76155785 @default.
- W2601549047 hasConceptScore W2601549047C8058405 @default.
- W2601549047 hasLocation W26015490471 @default.
- W2601549047 hasOpenAccess W2601549047 @default.
- W2601549047 hasPrimaryLocation W26015490471 @default.
- W2601549047 hasRelatedWork W1611256131 @default.
- W2601549047 hasRelatedWork W173766789 @default.
- W2601549047 hasRelatedWork W1965071464 @default.
- W2601549047 hasRelatedWork W2017031550 @default.
- W2601549047 hasRelatedWork W2097564540 @default.
- W2601549047 hasRelatedWork W2247903105 @default.
- W2601549047 hasRelatedWork W2587175632 @default.
- W2601549047 hasRelatedWork W2587813407 @default.
- W2601549047 hasRelatedWork W2588010295 @default.
- W2601549047 hasRelatedWork W2596264099 @default.
- W2601549047 hasRelatedWork W2601523758 @default.
- W2601549047 hasRelatedWork W2726578440 @default.
- W2601549047 hasRelatedWork W2739074253 @default.
- W2601549047 hasRelatedWork W2773275899 @default.
- W2601549047 hasRelatedWork W2894278939 @default.
- W2601549047 hasRelatedWork W2904509330 @default.
- W2601549047 hasRelatedWork W3023355490 @default.
- W2601549047 hasRelatedWork W3195285349 @default.
- W2601549047 hasRelatedWork W972168466 @default.