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Although the GPS/GNSS had become the primary source for Position, Navigation and Timing (PNT) information in maritime applications, the ultimate performance of the system can strongly degrade due to space weather events, deliberate interference and overall system failures. Within the presented work the development of an affordable integrated PNT unit for future on-board integrated system is presented. The system serves the task to collect and integrate the data from individual sensors in order to deliver the PNT information with a specified performance according to the requirements of the e-Navigation initiative proposed by the International Maritime Organization (IMO). The paper discusses an ongoing activity of replacing an expensive FOG inertial measurement unit with an affordable MEMS sensor system. Preliminary results of the system performance are presented for both static and dynamic scenarios using an Unscented Kalman filter with unit quaternions for the attitude parametrization.

Resilient determination of position, navigation and time (PNT) data of the vessel has been recognized as one core element of IMO’s e-Navigation strategy. As an associated member of the International Association of Marine Aids to Navigation and Lighthouse Authorities (IALA), the German Aerospace Center (DLR) is proposing the introduction of a shipside PNT Module as part of a future Integrated Navigation System (INS). The core of the ship side PNT Module is a sensor fusion based processing system (PNT Unit) using available radio navigation systems and services in combination with on-board sensors for PNT data generation. A focus of the PNT Unit is provision of integrity information for all PNT data in accordance with changing performance requirements during berth to berth navigation. Within the Maritime Traffic Engineering project the development of a first prototype of such a PNT Unit has been started in order to demonstrate the feasibility of such a PNT Unit. This paper will shortly introduce the basic concept of the PNT Module. The focus here will lie on the discussion on open regulatory aspects which have been raised during the prototype development. Secondly the results of a first realization of a PNT Unit will be presented. In the last part an overview of our latest developments of the shore based services at the Research Port Rostock will be given.

In einem Kurzvortrag wurden kurz die Themen der Arbeitsgruppe Nautische Systeme im Zusammenhang mit Weltraumanwendungen und der Partnerschaft zur Maritimen Universität Stettin vorgestellt.

Die Positionsbestimmung an Bord von Schiffen ist eines der Kernelemente der von der Internationalen Maritimen Organisation (IMO) 2006 initiierten e-Navigations Strategie. Die gesammelten Nutzeranforderungen belegen den Handlungsbedarf insbesondere bezüglich der Integrität von Positions-, Navigationsund Timing (PNT) Informationen. Basierend auf einer Analyse der aktuellen maritimen Standards sollen in diesem Vortrag ein Konzept für die zukünftige schiffseitige Bereitstellung von PNT Daten sowie erste experimentelle Ergebnisse zur schiffseitigen sensorfusionsbasierten PNT-Bestimmung vorgestellt und diskutiert werden.

Improvement and Indication of Reliability have been identified as important user needs within the e-Navigation strategy of the International Maritime Organization (IMO). This paper address the question, how these user needs can be satisfied in future with respect to resilient provision of position navigation and timing (PNT) data onboard the vessel. The idea of an onboard PNT Module is proposed as front-end between an integrated PNT system and ship-side applications like INS, AIS and ECDIS. The paper focuses on the integrity monitoring within the PNT Module. The concept is introduced and first experimental results are presented.

A high-level user need recognized by the IMO is the resilient provision of position, navigation, and time data (PNT) to ship-side applications such as Automatic Identification System (AIS), Electronic Chart Display Information System (ECDIS) and Integrated Navigation System (INS). In order to avoid collisions and groundings, a reliable knowledge of ship’s position and movement in relation to other traffic participants is necessary and enables an improved situation awareness taking into account the own maneuver possibilities in relation to external geo-referenced conditions. The PNT data provision should be ensured for all phases of ships’ navigation such as ocean, coast, port and docking. Therefore different and increasing requirements on accuracy, integrity, continuity and availability of PNT data should be taken into account. Resilience describes the aimed ability of the PNT system to provide the PNT data with the required performance in case of internal and external disturbances. Typical examples of such disturbances are the vulnerability of GNSS or the occurrence of malfunctions and failures in applied sensors and services. Overarching objective of the PNT enhancement can be derived from the user needs “improvement of reliability” and “indication of reliability”. The current and desired reliability of the PNT system should be measurable to quantify the aimed improvement of reliability. For instance, in IMO A.915(22) the minimum requirements on future GNSS are specified for the horizontal position and given in terms of accuracy, integrity, continuity and availability. A comparable norm for all desired PNT data is still missing. A consolidated specification of desired PNT data and assigned technical requirements are prerequisites for the identification of technical gaps of the current PNT system as well as for the provision and assessment of suitable approaches to overcome the existing gaps. However, the greatest challenge on the maritime PNT system comes from the user need “indication of reliability”. Indication of reliability describes the desire that in future the accuracy and integrity of all navigation relevant data should be automatically assessed. Initial point for an automatic assessment is the complete and unambiguous performance specification of all required output data and assigned tasks. For this purpose the generally admitted processing chains for PNT data provision composed by GNSS, PNT relevant terrestrial services as well as additional ship-side sensors should be taken into account. In minimum the current status of contributing PNT subsystems should be comprised to estimate their residual influence on resilient PNT data provision. Nevertheless, an automatic assessment of accuracy and integrity requires the implementation of integrity monitoring functionalities on the one hand as well as the deployment of redundancy within the PNT system to enable integrity monitoring on the other hand. Due to the multi-system, multi-service and multi-sensor based architecture of the maritime PNT system the development of an overarching integrity concept should be aimed. Such an integrity concept regulates responsibilities of single subsystems for integrity monitoring, identifies the minimum on redundancy and specifies additional interfaces to ensure the integrity messaging in an unambiguous manner. Regarding safety the integrity concept supports that the achieved and desired level of reliability will be measurable and specificable. Furthermore the tolerable residual risk of resilient PNT data provision (incidents) can be distributed on contributing components and can be optimised among them. Otherwise, approaches to improve critical components or to overcome gaps will be rateable regarding their benefits. The paper presents an initial guideline for the development and establishment of an Integrated PNT System to meet identified user needs in the future.

With respect to "GNSS in marine appications" the presentation was used to discuss some fundamental aspects concerning the new proposed resilient PNT unit as well as the role of integrity within the maritime community.

This paper focuses on a maritime integrated PNT Module as the on-board part of maritime PNT system. The aim of the PNT Module is the robust provision of position, navigation and timing information in accordance with the performance requirements of the actual operational region. The core of the PNT Module is a PNT Unit. This PNT Unit is a processing system, which combines by means of sensor and data fusion methods all available PNT sensors. The PNT Module is on the one hand part of the integrated PNT System and on the other hand part of the on- board INS. After a short discussion of the sensors of a PNT Module we have introduced a preliminary integrity monitoring concept for a PNT Module. In a first step towards the development of a PNT Module demonstrator system we have performed first measurement campaigns and derived PNT output data from different sensors. The analysis of these data shows, that for their usage within compatibility tests, the different locations of the sensors onboard the vessel needs to be considered.

A robust electronic position, navigation and timing system (PNT) is considered as one of the core elements for the realization of IMO-s (International Maritime Organization) e-Navigation strategy. Robustness can be interpreted as the capability of an integrated PNT system to provide PNT relevant data with the desired accuracy, integrity, continuity and availability under consideration of changing application conditions and requirements. Generally an integrated PNT system is a composite of service components – like GNSS, Augmentation Systems and terrestrial Navigation Systems – and an on-board integrated PNT Unit, which uses the available navigation and augmentation signals in combination with additional data of sensors aboard to provide accurate and robust PNT information of the ship. In this paper a concept of such an on-board integrated PNT Unit will be presented, which is designed to fulfill the specific user requirements for civil waterway applications. At first, the user requirements for an integrated PNT Unit will be overviewed. After that, existing integrity monitoring approaches will be analyzed. Finally, a first integration scheme for an inte-grated PNT Unit will be presented with a special focus on the internal integrity monitoring concept.

Die Präsentation ziehlte darauf hin, die Mitglieder des IALA e-Nav Komitees WG 2 (PNT) über den Entwicklungstand des DLR - PNT Unit Demonstrators zu informieren. Weiterhin wurde die Diskussion über über die noch offenen international festzulegenden Schnittstellen angestoßen.

Mención Internacional en el título de doctor Navigation information is an essential element for the functioning of robotic platforms and intelligent transportation systems. Among the existing technologies, Global Navigation Satellite Systems (GNSS) have established as the cornerstone for outdoor navigation, allowing for all-weather, all-time positioning and timing at a worldwide scale. GNSS is the generic term for referring to a constellation of satellites which transmit radio signals used primarily for ranging information. Therefore, the successful operation and deployment of prospective autonomous systems is subject to our capabilities to support GNSS in the provision of robust and precise navigational estimates. GNSS signals enable two types of ranging observations: –code pseudorange, which is a measure of the time difference between the signal’s emission and reception at the satellite and receiver, respectively, scaled by the speed of light; –carrier phase pseudorange, which measures the beat of the carrier signal and the number of accumulated full carrier cycles. While code pseudoranges provides an unambiguous measure of the distance between satellites and receiver, with a dm-level precision when disregarding atmospheric delays and clock offsets, carrier phase measurements present a much higher precision, at the cost of being ambiguous by an unknown number of integer cycles, commonly denoted as ambiguities. Thus, the maximum potential of GNSS, in terms of navigational precision, can be reach by the use of carrier phase observations which, in turn, lead to complicated estimation problems. This thesis deals with the estimation theory behind the provision of carrier phase-based precise navigation for vehicles traversing scenarios with harsh signal propagation conditions. Contributions to such a broad topic are made in three directions. First, the ultimate positioning performance is addressed, by proposing lower bounds on the signal processing realized at the receiver level and for the mixed real- and integer-valued problem related to carrier phase-based positioning. Second, multi-antenna configurations are considered for the computation of a vehicle’s orientation, introducing a new model for the joint position and attitude estimation problems and proposing new deterministic and recursive estimators based on Lie Theory. Finally, the framework of robust statistics is explored to propose new solutions to code- and carrier phase-based navigation, able to deal with outlying impulsive noises. La información de navegación es un elemental fundamental para el funcionamiento de sistemas de transporte inteligentes y plataformas robóticas. Entre las tecnologías existentes, los Sistemas Globales de Navegación por Satélite (GNSS) se han consolidado como la piedra angular para la navegación en exteriores, dando acceso a localización y sincronización temporal a una escala global, irrespectivamente de la condición meteorológica. GNSS es el término genérico que define una constelación de satélites que transmiten señales de radio, usadas primordinalmente para proporcionar información de distancia. Por lo tanto, la operatibilidad y funcionamiento de los futuros sistemas autónomos pende de nuestra capacidad para explotar GNSS y estimar soluciones de navegación robustas y precisas. Las señales GNSS permiten dos tipos de observaciones de alcance: –pseudorangos de código, que miden el tiempo transcurrido entre la emisión de las señales en los satélites y su acquisición en la tierra por parte de un receptor; –pseudorangos de fase de portadora, que miden la fase de la onda sinusoide que portan dichas señales y el número acumulado de ciclos completos. Los pseudorangos de código proporcionan una medida inequívoca de la distancia entre los satélites y el receptor, con una precisión de decímetros cuando no se tienen en cuenta los retrasos atmosféricos y los desfases del reloj. En contraposición, las observaciones de la portadora son super precisas, alcanzando el milímetro de exactidud, a expensas de ser ambiguas por un número entero y desconocido de ciclos. Por ende, el alcanzar la máxima precisión con GNSS queda condicionado al uso de las medidas de fase de la portadora, lo cual implica unos problemas de estimación de elevada complejidad. Esta tesis versa sobre la teoría de estimación relacionada con la provisión de navegación precisa basada en la fase de la portadora, especialmente para vehículos que transitan escenarios donde las señales no se propagan fácilmente, como es el caso de las ciudades. Para ello, primero se aborda la máxima efectividad del problema de localización, proponiendo cotas inferiores para el procesamiento de la señal en el receptor y para el problema de estimación mixto (es decir, cuando las incógnitas pertenecen al espacio de números reales y enteros). En segundo lugar, se consideran las configuraciones multiantena para el cálculo de la orientación de un vehículo, presentando un nuevo modelo para la estimación conjunta de posición y rumbo, y proponiendo estimadores deterministas y recursivos basados en la teoría de Lie. Por último, se explora el marco de la estadística robusta para proporcionar nuevas soluciones de navegación precisa, capaces de hacer frente a los ruidos atípicos. Programa de Doctorado en Ciencia y Tecnología Informática por la Universidad Carlos III de Madrid Presidente: José Manuel Molina López.- Secretario: Giorgi Gabriele.- Vocal: Fabio Dovis