Angling, M

Feltens, J.

Hernández Pajares, Manuel

Jakowski, Norbert

Zandbergen, R.

English

UPCommons. Portal del coneixement obert de la UPC

ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGEGlobal Ionospheric Monitoring  andNavigation SystemsJ. Feltens, M. Angling, N. Jakowski, M Hernández Pajares R Zandbergen1. - , . ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGEConsortium PartnersHewlett-Packard GmbH, Rüsselsheim, GermanyQinetiQ Ltd, Malvern, U.K.gAGE/UPCgAGE Polytechnical University of Catalonia (UPC) BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.es , , SpainGerman Aerospace Centre (DLR), Neustrelitz, Germany2ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGEOverview1. Introduction2. GNSS Based Methods to Monitor the Ionosphere3. Navigation-Critical Features of the Ionosphere4 Existing Ionosphere Modelling Techniques.    5. Requirements on New Ionosphere Modelling Methods to Meet Navigation Needs  6. Conclusions3ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE1. IntroductionTarget: Formulation of recommendations for a newionosphere monitoring system, meeting the requirementsof different types of potential users:1) Practically oriented users: Operational now / forecasting.2) Scientific users: Want to understand more about the upper earthatmosphere physics.A general overview of the study was presented in Session 5.Here, those aspects of the study which are of speciall f i ti h ll b hi hli ht d4re evance or nav ga on s a e g g e .ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE2. GNSS Methods to Monitor the IonosphereIGS:  400 sites Latency: daily hourly 15 minutes , ,   Data centres: CDDIS, IGN, KASI, SOPAC Access via FTP or in real-time via Internet (NTRIP)EUREF:  220 sites ( 50% at the same time IGS sites) Latency: daily, hourly, 15 minutes     Data centres: BKG, OLG Access via FTP or in real-time via Internet (NTRIP)5ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE2. GNSS Methods to Monitor the IonosphereCORS: Continental US, Pacific, Caribbean, Middle East Latency: 1 – 2 hours Data centre: NGS Access via FTP  GEONET: > 1200 sites Latency:  6 hours6 Data centre: GSI / JAS Access via FTP, real-time data upon requestESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE2. GNSS Methods to Monitor the IonosphereSpace-based GNSS can be used to: Derive electron density profiles from LEO altitude down to the bottom of the ionosphere Record TEC data from LEO altitude up to the 7GNSS spacecraft (up to 4000 radio links are available for one revolution period)ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE2. GNSS Methods to Monitor the IonosphereGNSS contributions to ionosphere monitoring expected for the future: About 1000 GNSS ground sites About 90 GNSS spacecraft (GPS, GLONASS, Galileo, Compass More frequencies)  Enhanced global coverageThese GNSS data are supplemented with non-GNSS data: I d ( IPS Di i d DIAS)onoson es e.g. , g son e,  LEO beacons Altimeter spacecraft8Australian IPS NetworkESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE3. Navigation - Critical Features of the IonosphereFor navigation applications, the following major ionospheric features must be captured with sufficient temporal and spatial resolution: The major regions of the ionosphere: equatorial anomaly, midlatitude trough, auroral oval, polar regions The typical variations of ionized layers: diurnal, seasonal, with solar cycle, l tit di l9a u na The ionosphere’s layered structure including the plasmasphereESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE3. Navigation - Critical Features of the Ionosphere perturbation TEC, 24−Aug−2005 TECUIonospheric effects: Ionospheric storms Travelling Ionospheric Disturbances (LSTIDs & MSTIDs) e  / °N 607012      ScintillationsLatitude 4050−10Universal Time/ hours 06:00 09:00 12:00 15:0030−2Ionospheric coupling with other geo-spheres: Magnetosphere Thermosphere10 Other, e.g. by induction through Rayleigh waves  (lithosphere, hydrosphere, atmosphere)ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE3. Navigation - Critical Features of the IonosphereIn turn GNSS systems could be used for: Solar flare monitoring:S l fl ibl f hi h f TEC t b ti t l b l l• o ar ares are respons e or g requency per ur a ons a g o a sca e.• During the recombination period TEC does not follow expected behaviour.• GNSS observing methods could be used for solar flares monitoring. Travelling Ionospheric Disturbances monitoring:• TIDs monitoring could be realised by setting up of dedicated local networks of GNSSreceivers.TID l d it fl t ti ti th h th i h lik• s are p asma ens y uc ua ons propaga ng roug e onosp ere as wave- estructures of 100 – 1000 km size and velocities of 50 – 400 m/s.• TIDs can produce amplitude fluctuations of 20 % of the TEC.• TIDs can significantly affect GNSS performance e g real-time ambiguity fixing, . . . Investigations into the so called 2nd and higher order terms:• The higher order terms of the TEC formula series expansion can produce additional delays ofseveral centimetres (especially the 2nd order term) in different extent for phase and11,pseudorange.• The higher order terms can not be neglected in high-precise GNSS applications (especiallyfor computing satellite clocks and orbits)!ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE4. Existing Ionosphere Modelling Techniques(those considered in the study)EDAM, QinetiQ Kalman filter data assimilation    Uses IRI 2007 as background model Magnetic coordinate system that remains fixed in space with respect to the Sun     Provides global 3D model in real-time Data types:– Ground and space-based slant TEC derived from GNSS data and altimeters– True height profiles from ionosondes and incoherent scatter radars12 – Electron density data from in-situ sensorsESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE4. Existing Ionosphere Modelling TechniquesTOMION, UPC Multi-step process TEC maps:– Two layer Kalman filter model to overcome mismodelling in classical single layer models            – Kriging to remove gaps and to capture smaller scale structure 3D grids:Improved Abel Transform inversion–    – Local to RO data– Uses TEC gradients from 2D maps Obser ation datav  :– Ground and space based slant TEC13ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE4. Existing Ionosphere Modelling TechniquesNeustrelitz TeC Model (NTCM), DLR Medians of assimilated TEC maps for North  Assimilation of ground-based GNSS measurements into the background TEC model NTCMPole area  for January 2002 The background model is a 60 terms polynomial as function of:– Hi(h) – diurnal and semidiurnal variation– Yj(d) – annual and semiannual variation– Lk(,,h,d) – dependence on solar zenith angleNTCM-NP model for 15 January – Sl(F10) – dependence on solar activity The model coefficients are updated yearly20025 3 2 214   1 1 1 1)10(),,,()()(i j k llkji FSdhLdYhHTEC ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE4. Existing Ionosphere Modelling TechniquesIONMON V2, HP at ESOC Closed function approach: profile functions for vertical electron density distribution are combined with surface functions to describe the horizontal     variation of profile function key parameters Vertical profiles can be  variants of the Chapman function or empirical profiles Analytic TEC integration Observation data: – Ground-based slant TEC– RO electron density profiles– Other electron density profiles (e g15    . . ionosonde) could be includedESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE4. Existing Ionosphere Modelling TechniquesNeQuick (3D reference model) Global 3D and time dependent ionospheric electron density model Analytical representation of the vertical profile (sum of Epstein layers) ofelectron density with continuous first and second derivatives Particularly developed for trans-ionospheric applications with directcalculation of slant TEC ITU standard model:– ITU-R Rec P.531 Used as the Galileo correction model– With updating provided by the Galileod tgroun segmen Latest version supplied by ICTP16ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE4. Existing Ionosphere Modelling TechniquesIGS TEC Maps (2D reference model) The IGS provides global vTEC mapson routine basis:– 13 TEC & RMS maps per day with 2-hour resolution– 2.5° lat  5° lon resolution– One daily set of satellite and station DCBs– Latency: 11 days in final mode 1 day     ,   in rapid mode– Accuracy of 1 to 2 TECU in regions well covered with GNSS receivers Combined product is weighted mean of the TEC maps computed by different analysis centres (UPC, ESOC, JPL, CODE) N.B. The maps are data driven17– Not a model in the conventional sense Future: Reduction of time resolution to 15 min, real-time & predicted TEC mapsESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE5. Requirements on New Ionosphere Modelling Methods to Meet Navigation NeedsA new system should combine the advantages of different methods: Background model to create a median ionosphere, combined with an assimilation part The background model should also create good median TEC representations The median model will be upgraded by assimilation of fresh observation data where available (GNSS-based & non-GNSS-based) The new system should describe ionosphere in 3D, inhere some basic physics and allow for future extensions to a real physics-based model The new system should allow for ionospheric predictions       The new system should be designed for two major groups of potential users:1) Practically oriented users. - Typical GNSS users belong to that category: Accurate ionospheric information to correct their GNSS data Near-real-time or real-time availability of ionospheric corrections & predictions182) Scientific usersESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGE6. ConclusionsPrincipally the development of a New European Ionosphere Monitoring,         System should follow two strategic lines:I) Development of a pragmatic solution for near-real-time data provisionbased on current near-real-time GNSS measurements: More and more GNSS tracking sites and systems are deployed More and more GNSS data will become available in real-time In the coming years ingestion techniques will improve and thin shellmodels will be replaced by dual-shell models Empirical 3D models (e.g. IRI), which can be used for backgroundmodelling, will continuously improve. Together with enhancedobservation data assimilation methods, 3D ionosphere modelling as awhole will improve in the coming yearsII) Preparation of future oriented physics-based modelling techniquesBoth activities should be established and supported by ESA and EC simultaneously19.ESOC Navigation Support OfficeBeacon Satellite Symposium 2010BarcelonaResearch group of Astronomy & GeomaticsTechnical University of Cataloniahttp://www.gage.esgAGE/UPCgAGEThank You!20

Global ionospheric monitoring and navigation systems

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Global ionospheric monitoring and navigation systems

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