{"id":{"repo_id":"tu-berlin","oai_identifier":"oai:depositonce.tu-berlin.de:11303/24359"},"canonical_url":"https://search.dev.ndltd.org/etd/tu-berlin/oai:depositonce.tu-berlin.de:11303/24359","repository":{"repo_id":"tu-berlin","name":"Technische Universität Berlin","base_url":"https://api-depositonce.tu-berlin.de/server/oai/request"},"display":{"title":"Multi-GNSS real-time precise satellite clock estimation","abstract":"Nowadays, Global Navigation Satellite Systems (GNSS) play a pivotal role in precise positioning in geosciences and various related domains. Among all GNSS positioning services, real-time precise point positioning (PPP) stands out for its global consistency and flexibility. The quality of real-time services based on PPP hinges particularly on the precision and resilience of satellite orbit and clock corrections. Despite its importance, maintaining continuous and long-term reliable real-time service remains a complex challenge. This dissertation introduces innovative methods, including algorithms, strategies, and system designs, to enhance the performance of real-time services. The core contributions of this work are highlighted below: An innovative approach for real-time clock rapid recovery is developed. Traditional clock estimation strategies require extensive time, often hours, to regain accuracy after interruptions, leading to significant gaps in real-time products and deteriorating the performance of real-time PPP services. The proposed method accelerates clock estimation restarts by leveraging historical data and previously saved filter state information, thus minimizing downtime. Additionally, it employs multi-thread processing to address the issue of thread concurrency effectively. A novel Decentralized Clock Estimation (DECE) strategy for high-rate real-time multi-GNSS clock estimation is also proposed. The complexity of updating clocks in real-time at high frequencies poses significant challenges, especially with the expansion of multi-GNSS constellations and the increasing number of stations. The DECE strategy enables multiple Un-Differenced (UD) estimators and Epoch-Differenced (ED) estimators running on separate computers and even locations, with their outputs merged to produce a unified clock estimation to reduce the computational burden and to improve the product availability. The experimental results show that the DECE method greatly enhances clock estimation efficiency while maintaining performance nearly identical to that of the original clock products. The evolution of the GNSS Real-Time Precision Positioning Service (RTPPS) system at the German Research Centre for Geosciences (GFZ) is comprehensively outlined in this dissertation. The system integrates real-time orbit determination, clock estimation, Uncalibrated Phase Delay (UPD) estimation, and PPP functionalities along with regional augmentation features, with a particular emphasis on system architecture and performance evaluation. Additionally, it extensively analyzes the impact of network configuration on real-time clock estimation. The Real-Time Positioning and Monitoring (RTPM) system is developed to retrieve real-time high-precision ground displacement for hazard monitoring and early warning in the framework of the Early-Warning and Rapid ImpaCt Assessment with real-time GNSS in the Mediterranean (EWRICA) project. The RTPM system has currently been deployed to the Rete INtegrata Nazionale GNSS (RING) network in Italy and the Badan Informasi Geospasial (BIG) network in Indonesia. its exceptional positioning performance has been demonstrated operationally. In summary, this dissertation primarily focuses on improving the performance of real-time precise positioning service, particularly in the real-time satellite clock estimation. The introduction of various new strategies has significantly improved the efficiency and stability of real-time GNSS service. Both experimental validation and in-field operational deployment through the EWRICA project have demonstrated that the improved RTPPS system can offer users a variety of PPP services, yielding promising results.","abstract_html":"Nowadays, Global Navigation Satellite Systems (GNSS) play a pivotal role in precise positioning in geosciences and various related domains. Among all GNSS positioning services, real-time precise point positioning (PPP) stands out for its global consistency and flexibility. The quality of real-time services based on PPP hinges particularly on the precision and resilience of satellite orbit and clock corrections. Despite its importance, maintaining continuous and long-term reliable real-time service remains a complex challenge. This dissertation introduces innovative methods, including algorithms, strategies, and system designs, to enhance the performance of real-time services. The core contributions of this work are highlighted below: An innovative approach for real-time clock rapid recovery is developed. Traditional clock estimation strategies require extensive time, often hours, to regain accuracy after interruptions, leading to significant gaps in real-time products and deteriorating the performance of real-time PPP services. The proposed method accelerates clock estimation restarts by leveraging historical data and previously saved filter state information, thus minimizing downtime. Additionally, it employs multi-thread processing to address the issue of thread concurrency effectively. A novel Decentralized Clock Estimation (DECE) strategy for high-rate real-time multi-GNSS clock estimation is also proposed. The complexity of updating clocks in real-time at high frequencies poses significant challenges, especially with the expansion of multi-GNSS constellations and the increasing number of stations. The DECE strategy enables multiple Un-Differenced (UD) estimators and Epoch-Differenced (ED) estimators running on separate computers and even locations, with their outputs merged to produce a unified clock estimation to reduce the computational burden and to improve the product availability. The experimental results show that the DECE method greatly enhances clock estimation efficiency while maintaining performance nearly identical to that of the original clock products. The evolution of the GNSS Real-Time Precision Positioning Service (RTPPS) system at the German Research Centre for Geosciences (GFZ) is comprehensively outlined in this dissertation. The system integrates real-time orbit determination, clock estimation, Uncalibrated Phase Delay (UPD) estimation, and PPP functionalities along with regional augmentation features, with a particular emphasis on system architecture and performance evaluation. Additionally, it extensively analyzes the impact of network configuration on real-time clock estimation. The Real-Time Positioning and Monitoring (RTPM) system is developed to retrieve real-time high-precision ground displacement for hazard monitoring and early warning in the framework of the Early-Warning and Rapid ImpaCt Assessment with real-time GNSS in the Mediterranean (EWRICA) project. The RTPM system has currently been deployed to the Rete INtegrata Nazionale GNSS (RING) network in Italy and the Badan Informasi Geospasial (BIG) network in Indonesia. its exceptional positioning performance has been demonstrated operationally. In summary, this dissertation primarily focuses on improving the performance of real-time precise positioning service, particularly in the real-time satellite clock estimation. The introduction of various new strategies has significantly improved the efficiency and stability of real-time GNSS service. Both experimental validation and in-field operational deployment through the EWRICA project have demonstrated that the improved RTPPS system can offer users a variety of PPP services, yielding promising results.","abstract_has_math":false,"creators":["Jiang, Xinyuan"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Schuh, Harald"],"committee_chairs":[],"committee_members":[],"year":2025,"date_issued":"2025","date_published":"2025","updated_at":"2026-07-27T21:28:57Z","subjects":[],"languages":["en"],"rights":[],"rights_urls":["https://creativecommons.org/licenses/by/4.0/"],"identifier_entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://doi.org/10.14279/depositonce-23173"],"render_values":[{"text":"https://doi.org/10.14279/depositonce-23173","href":"https://doi.org/10.14279/depositonce-23173","code":true}]}]},"links":{"outbound_url":"https://depositonce.tu-berlin.de/handle/11303/24359","outbound_label":"Repository record","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Schuh, Harald"]},{"key":"dc:creator","label":"Author","values":["Jiang, Xinyuan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2025-04-01T11:56:38Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2025-04-01T11:56:38Z"]},{"key":"dc:date.issued","label":"Date","values":["2025"]},{"key":"dc:type","label":"Dc Type","values":["Doctoral Thesis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights.uri","label":"Rights URI","values":["https://creativecommons.org/licenses/by/4.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://depositonce.tu-berlin.de/handle/11303/24359","https://doi.org/10.14279/depositonce-23173"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Nowadays, Global Navigation Satellite Systems (GNSS) play a pivotal role in precise positioning in geosciences and various related domains. Among all GNSS positioning services, real-time precise point positioning (PPP) stands out for its global consistency and flexibility. The quality of real-time services based on PPP hinges particularly on the precision and resilience of satellite orbit and clock corrections. Despite its importance, maintaining continuous and long-term reliable real-time service remains a complex challenge. This dissertation introduces innovative methods, including algorithms, strategies, and system designs, to enhance the performance of real-time services. The core contributions of this work are highlighted below: An innovative approach for real-time clock rapid recovery is developed. Traditional clock estimation strategies require extensive time, often hours, to regain accuracy after interruptions, leading to significant gaps in real-time products and deteriorating the performance of real-time PPP services. The proposed method accelerates clock estimation restarts by leveraging historical data and previously saved filter state information, thus minimizing downtime. Additionally, it employs multi-thread processing to address the issue of thread concurrency effectively. A novel Decentralized Clock Estimation (DECE) strategy for high-rate real-time multi-GNSS clock estimation is also proposed. The complexity of updating clocks in real-time at high frequencies poses significant challenges, especially with the expansion of multi-GNSS constellations and the increasing number of stations. The DECE strategy enables multiple Un-Differenced (UD) estimators and Epoch-Differenced (ED) estimators running on separate computers and even locations, with their outputs merged to produce a unified clock estimation to reduce the computational burden and to improve the product availability. The experimental results show that the DECE method greatly enhances clock estimation efficiency while maintaining performance nearly identical to that of the original clock products. The evolution of the GNSS Real-Time Precision Positioning Service (RTPPS) system at the German Research Centre for Geosciences (GFZ) is comprehensively outlined in this dissertation. The system integrates real-time orbit determination, clock estimation, Uncalibrated Phase Delay (UPD) estimation, and PPP functionalities along with regional augmentation features, with a particular emphasis on system architecture and performance evaluation. Additionally, it extensively analyzes the impact of network configuration on real-time clock estimation. The Real-Time Positioning and Monitoring (RTPM) system is developed to retrieve real-time high-precision ground displacement for hazard monitoring and early warning in the framework of the Early-Warning and Rapid ImpaCt Assessment with real-time GNSS in the Mediterranean (EWRICA) project. The RTPM system has currently been deployed to the Rete INtegrata Nazionale GNSS (RING) network in Italy and the Badan Informasi Geospasial (BIG) network in Indonesia. its exceptional positioning performance has been demonstrated operationally. In summary, this dissertation primarily focuses on improving the performance of real-time precise positioning service, particularly in the real-time satellite clock estimation. The introduction of various new strategies has significantly improved the efficiency and stability of real-time GNSS service. Both experimental validation and in-field operational deployment through the EWRICA project have demonstrated that the improved RTPPS system can offer users a variety of PPP services, yielding promising results.","Heutzutage spielen globale Navigationssatellitensysteme (GNSS) eine zentrale Rolle bei der präzisen Positionierung in den Geowissenschaften und verschiedenen verwandten Bereichen. Unter allen GNSS-Positionierungsdiensten zeichnet sich die Echtzeit-Präzisionspunktpositionierung (PPP) durch ihre globale Konsistenz und Flexibilität aus. Die Qualität der Echtzeitdienste, die auf PPP basieren, hängt insbesondere von der Präzision und Widerstandsfähigkeit der Satellitenorbit- und Uhrenkorrekturen ab. Trotz ihrer Bedeutung bleibt die Aufrechterhaltung eines kontinuierlichen und langfristig zuverlässigen Echtzeitdienstes eine komplexe Herausforderung. Diese Dissertation stellt innovative Methoden vor, einschließlich Algorithmen, Strategien und Systemdesigns, um die Leistung von Echtzeitdiensten zu verbessern. Die Kernbeiträge dieser Arbeit sind nachfolgend hervorgehoben: Eine innovative Methode zur schnellen Wiederherstellung von Echtzeituhren wird entwickelt. Traditionelle Strategien zur Uhrenschätzung erfordern viel Zeit, oft Stunden, um die Genauigkeit nach Unterbrechungen wiederzuerlangen, was zu erheblichen Lücken in den Echtzeitprodukten führt und die Leistung der Echtzeit-PPP-Dienste verschlechtert. Die vorgeschlagene Methode beschleunigt den Neustart der Uhrenschätzung durch die Nutzung historischer Daten und zuvor gespeicherter Filterzustandsinformationen, wodurch die Ausfallzeit minimiert wird. Zusätzlich wird die sog. multi-thread Verarbeitung eingesetzt, um das Problem der Thread-Parallelität effektiv zu adressieren. Eine neuartige dezentrale Uhrenabschätzungs- (DECE) Strategie zur Hochfrequenz-Echtzeit-Multi-GNSS-Uhrenschätzung wird ebenfalls vorgeschlagen. Die Komplexität der Echtzeitaktualisierung von Uhren mit hoher Frequenz stellt insbesondere mit der Expansion der Multi-GNSS-Konstellationen und der zunehmenden Anzahl von Stationen erhebliche Herausforderungen dar. Die DECE-Strategie ermöglicht es mehreren undifferenzierten (UD) Schätzern und epochen-differenzierten (ED) Schätzern, auf separaten Computern und sogar an verschiedenen Standorten zu laufen, wobei ihre Outputs zusammengeführt werden, um eine einheitliche Uhrenschätzung zu erzeugen, was den Rechenaufwand reduziert und die Produktverfügbarkeit verbessert. Die experimentellen Ergebnisse zeigen, dass die DECE-Methode die Effizienz der Uhrenschätzung erheblich verbessert, während die Leistung nahezu identisch mit der der ursprünglichen Uhrenprodukte bleibt. Die Entwicklung des GNSS-Echtzeit-Präzisionspositionierungsdienstes (RTPPS) Systems am Deutschen GeoForschungsZentrum (GFZ) wird in dieser Dissertation umfassend dargestellt. Das System integriert Echtzeit-Orbitbestimmung, Uhrenschätzung, Unkalibrierte Phasenverzögerung (UPD) Schätzung und PPP-Funktionalitäten sowie regionale Ergänzungsmerkmale, mit besonderem Schwerpunkt auf Systemarchitektur und Leistungsbewertung. Darüber hinaus wird der Einfluss der Netzwerkkonfiguration auf die Echtzeit-Uhrenschätzung ausführlich analysiert. Das Echtzeit-Positionierungs- und Überwachungssystem (RTPM) wurde entwickelt, um Echtzeit-Hochpräzisions-Bodendeformationen für die Gefahrenüberwachung und Frühwarnung im Rahmen des Projekts Early-Warning and Rapid ImpaCt Assessment with real-time GNSS in the Mediterranean (EWRICA) abzurufen. Das RTPM-System wurde derzeit im Rete INtegrata Nazionale GNSS (RING)-Netzwerk in Italien und im Badan Informasi Geospasial (BIG)-Netzwerk in Indonesien eingesetzt. Seine außergewöhnliche Positionierungsleistung wurde betriebsfähig demonstriert. Zusammenfassend konzentriert sich diese Dissertation hauptsächlich auf die Verbesserung der Leistung des Echtzeit-Präzisionspositionierungsdienstes, insbesondere bei der Echtzeit-Satellitenuhrenschätzung. Die Einführung verschiedener neuer Strategien hat die Effizienz und Stabilität des Echtzeit-GNSS-Dienstes erheblich verbessert. Sowohl die experimentelle Validierung als auch der operative Feldeinsatz durch das EWRICA-Projekt haben gezeigt, dass das verbesserte RTPPS-System den Benutzern eine Vielzahl von PPP-Diensten anbieten kann und vielversprechende Ergebnisse liefert."]},{"key":"dc:title","label":"Title","values":["Multi-GNSS real-time precise satellite clock estimation"]}]}],"canonical_facts":{"dc:contributor.advisor":["Schuh, Harald"],"dc:creator":["Jiang, Xinyuan"],"dc:date.accessioned":["2025-04-01T11:56:38Z"],"dc:date.available":["2025-04-01T11:56:38Z"],"dc:date.issued":["2025"],"dc:description.abstract":["Nowadays, Global Navigation Satellite Systems (GNSS) play a pivotal role in precise positioning in geosciences and various related domains. Among all GNSS positioning services, real-time precise point positioning (PPP) stands out for its global consistency and flexibility. The quality of real-time services based on PPP hinges particularly on the precision and resilience of satellite orbit and clock corrections. Despite its importance, maintaining continuous and long-term reliable real-time service remains a complex challenge. This dissertation introduces innovative methods, including algorithms, strategies, and system designs, to enhance the performance of real-time services. The core contributions of this work are highlighted below: An innovative approach for real-time clock rapid recovery is developed. Traditional clock estimation strategies require extensive time, often hours, to regain accuracy after interruptions, leading to significant gaps in real-time products and deteriorating the performance of real-time PPP services. The proposed method accelerates clock estimation restarts by leveraging historical data and previously saved filter state information, thus minimizing downtime. Additionally, it employs multi-thread processing to address the issue of thread concurrency effectively. A novel Decentralized Clock Estimation (DECE) strategy for high-rate real-time multi-GNSS clock estimation is also proposed. The complexity of updating clocks in real-time at high frequencies poses significant challenges, especially with the expansion of multi-GNSS constellations and the increasing number of stations. The DECE strategy enables multiple Un-Differenced (UD) estimators and Epoch-Differenced (ED) estimators running on separate computers and even locations, with their outputs merged to produce a unified clock estimation to reduce the computational burden and to improve the product availability. The experimental results show that the DECE method greatly enhances clock estimation efficiency while maintaining performance nearly identical to that of the original clock products. The evolution of the GNSS Real-Time Precision Positioning Service (RTPPS) system at the German Research Centre for Geosciences (GFZ) is comprehensively outlined in this dissertation. The system integrates real-time orbit determination, clock estimation, Uncalibrated Phase Delay (UPD) estimation, and PPP functionalities along with regional augmentation features, with a particular emphasis on system architecture and performance evaluation. Additionally, it extensively analyzes the impact of network configuration on real-time clock estimation. The Real-Time Positioning and Monitoring (RTPM) system is developed to retrieve real-time high-precision ground displacement for hazard monitoring and early warning in the framework of the Early-Warning and Rapid ImpaCt Assessment with real-time GNSS in the Mediterranean (EWRICA) project. The RTPM system has currently been deployed to the Rete INtegrata Nazionale GNSS (RING) network in Italy and the Badan Informasi Geospasial (BIG) network in Indonesia. its exceptional positioning performance has been demonstrated operationally. In summary, this dissertation primarily focuses on improving the performance of real-time precise positioning service, particularly in the real-time satellite clock estimation. The introduction of various new strategies has significantly improved the efficiency and stability of real-time GNSS service. Both experimental validation and in-field operational deployment through the EWRICA project have demonstrated that the improved RTPPS system can offer users a variety of PPP services, yielding promising results.","Heutzutage spielen globale Navigationssatellitensysteme (GNSS) eine zentrale Rolle bei der präzisen Positionierung in den Geowissenschaften und verschiedenen verwandten Bereichen. Unter allen GNSS-Positionierungsdiensten zeichnet sich die Echtzeit-Präzisionspunktpositionierung (PPP) durch ihre globale Konsistenz und Flexibilität aus. Die Qualität der Echtzeitdienste, die auf PPP basieren, hängt insbesondere von der Präzision und Widerstandsfähigkeit der Satellitenorbit- und Uhrenkorrekturen ab. Trotz ihrer Bedeutung bleibt die Aufrechterhaltung eines kontinuierlichen und langfristig zuverlässigen Echtzeitdienstes eine komplexe Herausforderung. Diese Dissertation stellt innovative Methoden vor, einschließlich Algorithmen, Strategien und Systemdesigns, um die Leistung von Echtzeitdiensten zu verbessern. Die Kernbeiträge dieser Arbeit sind nachfolgend hervorgehoben: Eine innovative Methode zur schnellen Wiederherstellung von Echtzeituhren wird entwickelt. Traditionelle Strategien zur Uhrenschätzung erfordern viel Zeit, oft Stunden, um die Genauigkeit nach Unterbrechungen wiederzuerlangen, was zu erheblichen Lücken in den Echtzeitprodukten führt und die Leistung der Echtzeit-PPP-Dienste verschlechtert. Die vorgeschlagene Methode beschleunigt den Neustart der Uhrenschätzung durch die Nutzung historischer Daten und zuvor gespeicherter Filterzustandsinformationen, wodurch die Ausfallzeit minimiert wird. Zusätzlich wird die sog. multi-thread Verarbeitung eingesetzt, um das Problem der Thread-Parallelität effektiv zu adressieren. Eine neuartige dezentrale Uhrenabschätzungs- (DECE) Strategie zur Hochfrequenz-Echtzeit-Multi-GNSS-Uhrenschätzung wird ebenfalls vorgeschlagen. Die Komplexität der Echtzeitaktualisierung von Uhren mit hoher Frequenz stellt insbesondere mit der Expansion der Multi-GNSS-Konstellationen und der zunehmenden Anzahl von Stationen erhebliche Herausforderungen dar. Die DECE-Strategie ermöglicht es mehreren undifferenzierten (UD) Schätzern und epochen-differenzierten (ED) Schätzern, auf separaten Computern und sogar an verschiedenen Standorten zu laufen, wobei ihre Outputs zusammengeführt werden, um eine einheitliche Uhrenschätzung zu erzeugen, was den Rechenaufwand reduziert und die Produktverfügbarkeit verbessert. Die experimentellen Ergebnisse zeigen, dass die DECE-Methode die Effizienz der Uhrenschätzung erheblich verbessert, während die Leistung nahezu identisch mit der der ursprünglichen Uhrenprodukte bleibt. Die Entwicklung des GNSS-Echtzeit-Präzisionspositionierungsdienstes (RTPPS) Systems am Deutschen GeoForschungsZentrum (GFZ) wird in dieser Dissertation umfassend dargestellt. Das System integriert Echtzeit-Orbitbestimmung, Uhrenschätzung, Unkalibrierte Phasenverzögerung (UPD) Schätzung und PPP-Funktionalitäten sowie regionale Ergänzungsmerkmale, mit besonderem Schwerpunkt auf Systemarchitektur und Leistungsbewertung. Darüber hinaus wird der Einfluss der Netzwerkkonfiguration auf die Echtzeit-Uhrenschätzung ausführlich analysiert. Das Echtzeit-Positionierungs- und Überwachungssystem (RTPM) wurde entwickelt, um Echtzeit-Hochpräzisions-Bodendeformationen für die Gefahrenüberwachung und Frühwarnung im Rahmen des Projekts Early-Warning and Rapid ImpaCt Assessment with real-time GNSS in the Mediterranean (EWRICA) abzurufen. Das RTPM-System wurde derzeit im Rete INtegrata Nazionale GNSS (RING)-Netzwerk in Italien und im Badan Informasi Geospasial (BIG)-Netzwerk in Indonesien eingesetzt. Seine außergewöhnliche Positionierungsleistung wurde betriebsfähig demonstriert. Zusammenfassend konzentriert sich diese Dissertation hauptsächlich auf die Verbesserung der Leistung des Echtzeit-Präzisionspositionierungsdienstes, insbesondere bei der Echtzeit-Satellitenuhrenschätzung. Die Einführung verschiedener neuer Strategien hat die Effizienz und Stabilität des Echtzeit-GNSS-Dienstes erheblich verbessert. Sowohl die experimentelle Validierung als auch der operative Feldeinsatz durch das EWRICA-Projekt haben gezeigt, dass das verbesserte RTPPS-System den Benutzern eine Vielzahl von PPP-Diensten anbieten kann und vielversprechende Ergebnisse liefert."],"dc:identifier.uri":["https://depositonce.tu-berlin.de/handle/11303/24359","https://doi.org/10.14279/depositonce-23173"],"dc:language.iso":["en"],"dc:rights.uri":["https://creativecommons.org/licenses/by/4.0/"],"dc:title":["Multi-GNSS real-time precise satellite clock estimation"],"dc:type":["Doctoral Thesis"]},"updated_at":"2026-07-27T21:28:57Z"}