Report on EGNOS application as effective augmentation system for marine positioning in inland and pilot navigation. Submitted by Germany and Poland *

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1 E SUB-COMMITTEE ON NAVIGATION, COMMUNICATIONS AND SEARCH AND RESCUE 4th session Agenda item 6 NCSR 4/INF.16/Rev.2 28 February 2017 ENGLISH ONLY GUIDELINES ASSOCIATED WITH MULTI-SYSTEM SHIPBORNE RADIONAVIGATION RECEIVERS DEALING WITH THE HARMONIZED PROVISION OF PNT DATA AND INTEGRITY INFORMATION Report on EGNOS application as effective augmentation system for marine positioning in inland and pilot navigation Submitted by Germany and Poland * SUMMARY Executive summary: This document provides information on the study of an EGNOS application as an effective augmentation system for marine positioning in inland and pilot navigation, supporting the development of the Guidelines for shipborne Position, Navigation and Timing (PNT) data processing presented in document NCSR 4/6.The reported work has been performed under a contract of the European Space Agency within the European GNSS Evolutions Programme (EGEP). Strategic direction: 5.2 High-level action: Output: Action to be taken: Paragraph 13 Related documents: NCSR 4/6; resolutions A.915(22), A.1046(27) and MSC.401(95) Introduction 1 Within the e-navigation strategy, the Organization has identified the user need for improved reliability, resilience and integrity of bridge equipment and navigation information as one of the five prioritized e-navigation solutions (NAV 54/WP.6, NCSR 1/9). * Note by the Secretariat: This revision was only to delete the logo from ESA from the front page of the attached report.

2 Page 2 2 The European Space Agency (ESA), in 2015, commissioned the study jointly performed by the Maritime University of Szczecin (MUS) in Poland and the German Aerospace Center (DLR) on implementation of EGNOS in the Maritime Domain as Effective Augmentation System for POsitioning in Inland and Pilot NAvigation (EMPONA). The main objectives of the study were to:.1 define the role of EGNOS from a marine user's perspective focusing on the possible benefits of GNSS-related integrity data provided by SBAS within the ship's bridge environment;.2 define marine operations and nautical tasks in which SBAS correction and integrity data could be beneficial; and.3 propose meaningful requirements for a PNT data processing integrated in ECDIS with special account to its integrity in specific operations by simulation analysis of designed scenarios. 3 The report, set out in the annex, contains the results of the study, thus providing information supporting the proposed draft of the Guidelines for shipborne Position, Navigation and Timing (PNT) data processing (NCSR 4/6). Background 4 The SBAS integrity concept is based on the following definitions:.1 Integrity Risk: the probability that the position error is larger than the alert limit defined for the intended operation and the user is not warned within the Time To Alert (TTA)..2 Integrity Event: occurs when the Navigation System Error is greater or equal to the corresponding Protection Level for the corresponding service level and the receiver does not trigger an alert within the Time To Alert (TTA)..3 Alert Limit: the error tolerance not to be exceeded without issuing an alert. 5 The EGNOS integrity concept relies on the use of a network of ground reference stations which receive data from the GPS satellites and compute integrity and correction data. This information is uploaded to the EGNOS geostationary satellites which then relay this information to EGNOS receivers through the EGNOS SIS. The EGNOS receivers acquire and apply this data to determine the integrity and improve the accuracy of the computed navigation solution. Therefore, the SBAS integrity service protects the user from both:.1 failures of GPS satellites by detecting and excluding faulty satellites through triggering SBAS system-designed barriers; and.2 transmission of erroneous or inaccurate differential corrections. These erroneous corrections may in turn be induced from various sources and should be eliminated through triggering SBAS system designed barriers. The EGNOS ground system, using the measures taken from the observation of the GPS constellation through its dedicated network of reference ground stations, provides separate corrections and bounds to the satellite ephemeris errors, clock errors and ionospheric errors.

3 Page 3 6 Since the SBAS standards have been initially developed to meet the stringent navigation performance requirements applicable to civil aviation approach and landing operations, the reference SBAS receiver standards have also been developed by the civil aviation community. These standards are published by the Radio Technical Commission for Aeronautics (RTCA) under the reference DO-229 (SBAS Minimum Operational Performance Standards MOPS). They support both horizontal and vertical navigation and implement a large number of features aimed at ensuring the integrity of the derived position. 7 At this stage, no unique standard exists describing the use of EGNOS messages for OS users, including marine users. Nevertheless, SBAS receiver designed to support the EGNOS Open Service (OS) is expected to:.1 decode and apply satellite clock corrections (broadcast through message types 2-5 and corresponding to satellites selected by message type 1);.2 decode and apply satellite ephemeris corrections (broadcast though message types 24-25);.3 decode and apply ionospheric corrections (broadcast through message type 26 for ionospheric grid points selected by message type 18); and.4 take into account major warnings and integrity data sent through the SBAS messages (broadcast through message types 2-5 and 6). Summary of the report 8 The study in the EMPONA project included:.1 analysis of opportunities for an efficient implementation of EGNOS Open Service (OS) into the maritime PNT system and discussion of various utilization concepts;.2 collection and analysis of real measurement data; and.3 full mission ship bridge simulation (FMBS) including EGNOS functionality to prove by simulation the influence of EGNOS system, and specifically its integrity data, on marine navigation performance and safety. 9 The results of the measurement campaign and FMBS studies proved that GNSS augmented by EGNOS meets or exceeds requirements set out in resolution A.1046(27), MSC Performance standards MSC.112(73), MSC.113(73), MSC.114(73), MSC.115(73), MSC.233(83), MSC.252(83), MSC.379(93), and GNSS future needs adopted in resolution A.915(22). 10 The main result of the study was the model of Marine Vessel Protection Area (MVPA). MVPA is dependent on: geometry of visible GNSS satellites, estimates of signal propagation errors and other EGNOS-based integrity data, the ship's size, the ship's heading and its estimated accuracy, position of the GNSS/EGNOS antenna relative to the ship's hull.

4 Page 4 11 The major finding from FMBS tests was that presentation of MVPA increases navigator's awareness and ship's safety if displayed graphically in addition to circular horizontal protection level, alert limit and SBAS status alert mark in ECDIS or INS systems. 12 For detailed information on the research results please contact: irm@am.szczecin.pl Action requested of the Sub-Committee 13 The Sub-Committee is invited to note the information provided in this document. ***

5 Annex, page 1 ANNEX EMPONA Project Report on EGNOS application as effective augmentation system for marine positioning in inland and pilot navigation: SBAS requirements during conduction of accuracy-critical navigation tasks

6 Annex, page 2 CONTENTS: 1. INTRODUCTION POSITIONING REQUIREMENTS IN THE CURRENT IMO REGULATIONS FINDINGS IN THE EMPONA PROJECT SBAS MARINE REQUIREMENTS PRODUCED AS A RESULT OF EMPONA PROJECT REFERENCES... 15

7 Annex, page 3 1 INTRODUCTION Since the SBAS standards have been initially derived to meet the stringent navigation performance requirements applicable to civil aviation approach and landing operations, the reference SBAS receiver standards have also been developed by the civil aviation community. These standards are called SBAS Minimum Operational Performance Standards (MOPS) and are published by the Radio Technical Commission for Aeronautics (RTCA) under the reference DO-229 [RD-6]. For non-aviation Open Service (OS) users [RD-1], alternative EGNOS message processing may be implemented, deviating from the [RD-6]. The EGNOS system performance has not been characterised for such a receiver configuration and therefore the performance experienced by such devices is not covered in the current version of EGNOS OS [RD-1] or SoL Service Definition [RD-2]. Also, the verification of EGNOS system performance against the positioning requirements set in the current IMO regulations has not yet been fully performed. The EMPONA project has been commissioned to deal with these problems. The study in EMPONA project included: a) analysis of opportunities for an efficient implementation of EGNOS Open Service (OS) into the maritime PNT system and discussion of various utilization concepts; b) collection and analysis of real measurement data; and c) full mission ship bridge simulation (FMBS) including EGNOS functionality to prove by simulation methods the influence of EGNOS system, and specifically its integrity data, on marine navigation performance and safety. The main finding was that since the utilization of SBAS integrity data in the maritime domain is very ship-specific, it must take into account several aspects, influencing protection area dimensions evaluated primarily in horizontal dimensions. These include signal coverage and geometry aspects, ship's size, ship's heading accuracy and ship's position of the Global Navigation Satellite System's (GNSS) antenna in the body reference frame. Therefore, the proposed output of EGNOS messages processing for marine users was the MVPA (Marine Vessel Protection Area) taking all of the above aspects into account and displayed graphically within the ECDIS environment as the protection area around ship's contour together with the standard circular HPL. The validation of EGNOS based MVPA concept usability was performed via Full Mission Bridge Simulation (FMBS) studies with input data modelled from real measurements.

8 Annex, page 4 2 POSITIONING REQUIREMENTS IN THE CURRENT IMO REGULATIONS The maritime community facilitates the requirements on GNSS in 3 different ways:.1 [RD-3] The document "WORLDWIDE RADIONAVIGATION SYSTEM deals with the provision of global, regional and local radionavigation systems and their recognition for ships' navigation by the IMO. The latest version of this resolution [IMO A.1046(27)] was adopted in 2011 and describes the operational requirements on radionavigation systems and services based on required position performance at user site. At this point it should be mentioned, that the document is based on 2 performance levels representing requirements on GNSS for general ships' navigation: a) navigation in ocean waters and b) navigation in harbour entrances, harbour approaches and coastal waters..2 [RD-4] The document "Revised Maritime Policy And Requirements For A Future Global Navigation Satellite System (GNSS)" [IMO A.915(22)] provides an initial list of maritime performance requirements on GNSS positioning in relation to general ships' navigation and additionally for other maritime applications. More than 2 performance levels were introduced to provide requirements for the intermodal use of GNSS taking into account the increasing variety of nautical functions. The resolution was adopted in 2002 as maritime complement to "aviation requirements for a future GNSS" developed by the International Civil Aviation Organization. Since then, neither a consolidation nor an evaluation of these requirements had taken place in the maritime community..3 [RD-5] Since the nineties IMO's Maritime Safety Committee (MSC) has brought a variety of performance standards in force to enable the type approval of on-board radionavigation equipment. Due to the historical development these performance standards are inconsistent e.g. regarding the requirements on integrity monitoring. Integrity, according to IMO Maritime Policy and Requirements for GNSS [RD-3], is the ability to provide users with warnings within a specified time when the system should not be used for navigation. It is coincident with the [RD-2] definition of a measure of the trust which can be placed in the correctness of the information supplied by a given system which includes the ability of a system to provide timely and valid warnings to the user (alerts) when the system must not be used for the intended operation (or phase of flight). The current maritime policy of requirements for GNSS [RD-3] describes SBAS integrity by three parameters fixed for specified kinds of operations (phase of navigation): the threshold value or alert limit, the time to alarm and the integrity risk. The output of integrity monitoring is that individual (erroneous) observations or the overall GNSS system cannot be used for navigation, where "Internal integrity monitoring" is performed aboard a craft, and "External integrity monitoring" is provided by external stations. The integrity risk is the probability that a user will experience a position error larger than the threshold value without an alarm being raised within the specified time to alarm at any instant of time at any location in the coverage area. IMO's A915(22) [RD-3] marine requirements of GNSS during conduction of accuracy-critical navigation tasks as presented in the table 2.1 actually constitute the IMO policy towards future standards and are not adopted as current applicable performance standards.

9 Annex, page 5 Table 2.1: Minimum maritime user requirements for general navigation (accuracy at 95% confidence level) [RD-3]. 3 FINDINGS IN THE EMPONA PROJECT The measurement campaign and the full mission bridge simulator (FMBS) studies conducted in the EMPONA project aimed to define the role of European Geostationary Navigation Overlay System (EGNOS) from a marine user perspective. The work was focused on the possible benefits of Satellite Based Augmentation Systems (SBAS) integrity data presentation within the ship's bridge environment. Evaluation of: 1) EGNOS utilization concepts in the maritime domain, and 2) Marine Vessel Protection Area (MVPA) model, were the objectives of these activities EGNOS OS positioning performance in maritime domain During the measurement campaign in the western part of Baltic Sea, mostly along the Polish coastline and the waterway between Świnoujście and Szczecin, the EGNOS OS based positioning and the GPS raw data measurements were recorded over a time span of 62 days. Based on this data set, which covered different environmental conditions (e.g. swell, influence of obstacles and bridges) and various scenarios (e.g. navigation in a harbour, canal or coastal areas), the current performance of this augmentation system in maritime domain was analysed with respect to the availability, continuity and accuracy of the obtained positioning solutions [RD-8]. It was found that EGNOS corrections as well as EGNOS based positioning had full availability except for some minor interruptions nearby and below bridges which were passed by the ship. Here shadowing effects of the bridges prevent the undisturbed reception of both EGNOS and GPS signals. The horizontal accuracy of the positioning was below 0.9 m (95% confidence level) during the whole measurement campaign, as reported for the open service by the EGNOS service provider for this period of time. It is worth to mention that the receiver used for the calculation of EGNOS based positions made use of proprietary filtering and smoothing techniques that might lead to an overestimation of accuracy. When comparing the achieved accuracy and continuity with the user requirements formulated by IMO, EGNOS would be usable for costal operation and port approach as well as for port operation.

10 Annex, page MVPA model The measurement campaign conducted on board m/v Nawigator XXI, cruising Polish and German inland and coast waters, provided feedback to the models constructed for simulation purposes (especially regarding the measurements' errors estimates). The data gathered in the measurement test cases (TCs) formed the basis for distribution of accuracy estimates in GNSS integrity parameters and instantaneous position and heading errors adopted for simulation TCs. The MVPA model developed in EMPONA [RD-7] took into consideration several aspects influencing protection area dimensions. These included GNSS signal coverage aspects (measurements' errors depend on geometry of visible satellites and the signal propagation), the ship's size, the ship's heading and its estimated accuracy, position of the GNSS/EGNOS antenna relative to the ship's hull, and EGNOS integrity data. The first step was determination of the uncertainty ellipse at CCRP, the second its propagation to the fixed points of ship's horizontal contour, and the third finding of the extreme outer points of the resultant ellipses (fig. 1). Figure. 1: Finding of the extreme outer points of the protection ellipses. The resultant MVPA was displayed graphically within the Electronic Chart Display and Information System (ECDIS) environment. This ECDIS layer constituted an EGNOS integrity display within bridge environment showing graphical representation of the ship and integrity information (protection levels in conjunction with alert limits).

11 Annex, page FMBS study The experiments conducted in the controlled environment of navigational FMBS (see fig. 2) provided: a) testing of influence of various navigational conditions and marine operations on MVPA dimensions, b) alert limit (AL) estimation and prediction for specific ships and conditions, c) evaluation of general influence of EGNOS system on marine navigation performance and safety during inland and pilot manoeuvring (simulations with and without EGNOS based MVPA). These experiments initially covered all areas defined in table 2.1 at system level: ocean, coastal, port approach and restricted waters, port, inland waterways. But preliminary results of statistical analysis proved that only in critically confined waters, like fairways, inland waterways, and harbours of minimum safe parameters for the manoeuvring vessel, the relevant quantitative values showing EGNOS MVPA impact on safety can be achieved (due to relatively small dimensions of the MVPA). The final simulations and analysis were restricted to port approach and restricted waters, port and inland waters and consisted of 4 scenarios each of 2 variants covered in table 3.1 (the SVCC acronym stands for Simulated Vessel Collision Contour as opposed to less accurate AIS contour). The basic rule was that the simulation trials were conducted twice: with and without presentation of information coming from EGNOS in ECDIS display. The applied k-factor and fixed offset corresponded to the coverage factor of established protection area (MVPA) confidence level, and constant bias to one side of the vessel for prolonged period which enabled worst case scenarios. The rationale for the k-factor came from the assumption of uncertainty normal distribution in both the North and the East directions of position ordinates. For example, to create a 95% confidence ellipse from the 1σ error ellipse, a factor of k 2.45 must be used; in contrast, to get a 99.8% confidence level, a factor of k 3.5 must be used, and so on.

12 Annex, page 8 Figure 2: Full Mission Bridge Simulator used in the study Table 3.1: Simulation scenarios description. EGNOS has been designed to meet SBAS SoL performance requirements as stated in table 3.2 for aviation users [RD-2]. The most demanding performance level met by EGNOS is of integrity risk of 2*10-7 /150s against a Horizontal Alert Limit (HAL) of 40 meters (table 3.2). This is equivalent to 4.8*10-6 /hour or 1.4*10-5 per 3 hours. For the maritime users the proposed

13 Annex, page 9 requirements (table 2.1) are: integrity risk of 10-5 per 3 hours against the HAL required for port approach, restricted waters, and inland waterways of 25m. In case of the port area the HAL criterion goes down to 2.5m with integrity risk remaining at 10-5 per 3 hours. Because of different HAL values against integrity risk the current EGNOS requirement cannot be directly compared to the IMO requirement, but it is highly likely that the IMO requirement is met by the current system baseline. The measurement campaign aboard m/v "Nawigator XXI" confirmed it, but still other detailed measurements have to be performed for the maritime domain to prove this view. In FMBS study, coverage k-factor of 7.0 or larger was used for MVPA and HPL calculation. This corresponds to an integrity risk of 10-5 per 3 hours or 10-9 per second (one second was assumed as a position latency/update step in shipborne GNSS receivers), or 10-6 per 15 minutes (typical length of selected ship manoeuvres) Table 3.2: Minimum aviation user performance requirements of SBAS [RD-2], [RD-6]. The main goal of FMBS scenarios 1 and 2 (table 3.1) was to enter to Outer Świnoujście Port by LNG Q-Flex size carrier under ballast condition (port approach and restricted waters area according to table 2.1). Area, ship, type of manoeuvre, navigational conditions and hydro-meteorological conditions were chosen to simulate ship's passage near objects that are considered as dangerous for navigation and are not clearly visible by the navigator (due to restricted visibility and/or lack of proper warning marks). The navigator's task was to keep the ship inside the available navigational area and as far as possible from the unmarked and dangerous to navigation object located on the starboard side. This situation required that the navigator had to keep the ship as close as possible to the east breakwater head taking available depth and risk of grounding into consideration. Depending on the scenario variant the main sources of navigational information were visual observation and electronic chart with vessel contour or electronic chart with vessel contour and MVPA visualisation (figure 3). On the basis of the recorded parameters the following variables were calculated and analysed for both variants in these scenarios: a) dimensions of safe manoeuvring areas, b) probability of grounding on safety isobaths, c) minimum distances to characteristic points There were no significant differences between widths of manoeuvring areas in both scenarios variants (fig. 4). But the manoeuvring area (ship's swept path) in scenario with MVPA (EGNOS integrity data) presented was evidently shifted further from the dangerous isobath. There was a significant difference between maximum grounding probabilities in both scenario variants much lower probability (7-times) was achieved with MVPA shown in ECDIS. Also, there was a significant difference between minimum distances in both variants of the scenario (fig. 4).

14 Annex, page 10 Figure 3: Ship contour and MVPA visualization within ECDIS in scenario 1B. Figure 4: Safe manoeuvring areas of simulation scenarios 1A & 1B. The main goal of scenario 3 was to perform the mooring manoeuvres of Świnoujscie-max ferry to the berth of Świnoujście Ferry Terminal (port area according to table 2.1). The area, ship, navigational conditions and hydro-meteorological conditions were chosen to simulate a real mooring manoeuvre of a ferry. The navigator's task was to approach the berth with minimum values of surge and sway velocities which give minimum energy of contact between the ferry

15 Annex, page 11 and the fender. Additionally, the navigator was obliged to conduct this manoeuvre in a safe manner but as fast as practicably possible. The main assumption for scenario no. 3 was to prove the relation between the type of waterline contour visualization and navigator's situational awareness, which has a direct impact on the quality of such precision manoeuvres. The main source of navigational information, apart from the visual observation, was the electronic chart with ship's AIS contour and MVPA visualisation. The restricted visibility conditions were simulated where ECDIS was the only reliable source of position information. Recorded parameters were used to calculate the resultant velocity during the first contact of the ferry with the fender in each simulation. The resultant speed measured at the moment of first ship-shore contact in simulation scenario 3 was significantly (about 5-times) lower while displaying MVPA. The main goal of scenario 4 was to perform safe passing of the vessel on the opposite course in inland waterway (inland waterways area according to table 2.1). The model of training/survey vessel m/v "Nawigator XXI" was used in this scenario. The area, ship, navigational and hydro-meteorological conditions were chosen to simulate ship's passage near objects that are considered as dangerous to navigation, and are visible only from a short distance. Simulated scenarios were designed to properly imitate real, dangerous situations that have place when two ships are passing each other in a restricted area (in a narrow passage). The navigator's task was to keep the ship inside the available navigational area and as far it was possible from a ferry proceeding on opposite course and located at the port side. Additionally, the navigator had to maintain a safe distance from the berth that was located at the starboard side. This berth was equipped with high elements of the port infrastructure. The most relevant danger to navigation in this area was the strengthened corner of the Zbozowe berth, which is not visible by navigators in restricted visibility conditions. Such conditions require that a navigator has to rely on information acquired from ECDIS. The initial speed of both ships was set to 6 knots. Distance between both ships was equal to 3 lengths of the m/v "Nawigator XXI". After the ferry started to be visually observable the navigator had to change the course to the starboard. At that time the corner of Zbozowe berth was not yet visible. The navigator had to evaluate the distance to both obstructions using ECDIS and visual observation and then conduct the passing manoeuvre. There were no significant differences between widths of manoeuvring areas in scenario 4. But the manoeuvring area (ship's swept path) in scenario with MVPA shown was evidently shifted about to port side further from the dangerous land infrastructure. The collision probability was much higher in scenario without MVPA, when with MVPA it was practically negligible (less than 10-4 ). Also, there was a significant difference between average minimum and max minimum distance in both variants of the scenario FMBS result summary The results of statistical analysis of all scenarios proved that presentation of EGNOS integrity data as graphical MVPA makes the navigator to lead the ship further from the danger and with lower (safer) speed while approaching the quay. Generally when integrity parameters were displayed, it led to an increase of awareness and cautiousness at the navigators' side, and the knowledge of ship's contour position uncertainty, shown graphically in ECDIS around the model ship's contour, additionally influenced navigator to hold extra safety margins. So, the added value was brought evidently by the integrity data, while the expectation of high accuracy of GNSS and heading measurements usually led to overreliance on electronic positioning. Concluding: the availability of EGNOS and other electronic position fixing systems (EPFS) integrity data is especially necessary in marine operations performed via EPFS only. It could enable monitoring of navigation risk in restricted waters in restricted visibility or precision manoeuvring close to obstacles or berths not easily visible from the ship's bridge. SBAS provides integrity data estimating the current position accuracy and this is essential information for improved situation awareness of the navigator.

16 Annex, page 12 Still the important factor is the proper training of navigators in utilisation of EGNOS integrity function. The concept of MVPA and colour marked alerts is intuitive but further usability testing by means of eye tracking devices and situation awareness analysis should be conducted in the future. 4. SBAS MARINE REQUIREMENTS PRODUCED AS A RESULT OF EMPONA PROJECT The measurement campaign and FMBS studies proved that GNSS augmented by EGNOS OS meets or surpasses requirements put in IMO GNSS policy [RD-3] and IMO GNSS performance standards [RD-5]. The suggested proposal of change to the IMO GNSS policy [RD-3] resulting from the EMPONA project covers MVPA functionality as follows: A. The requirements presented in table 2.1 should include graphical presentation of Marine Vessel Protection Area (MVPA) in addition to circular horizontal protection level limited by alert limit and SBAS status alert mark (colour coded). The input quantities for the integrity algorithm on the user side should be:.1 GNSS position of vessel;.2 Heading of the vessel;.3 Geometry between GNSS satellites and user derived position from observations of the GNSS satellites;.4 GNSS integrity data transmitted by SBAS;.5 Vessel contour data in Electronic Chart System;.6 Vessel's heading device integrity data;.7 GNSS antenna offset in ship-body frame;.8 Estimated error of signal multipath;.9 Estimated technical error of the GNSS receiver;.10 Coverage factor based on integrity risk value; The resultant MVPA is to be built from extreme outer points for each uncertainty ellipse fixed to vessel contour points (see fig. 5).

17 Annex, page 13 Figure 5: Example of MVPA around ship heading to 45 in body-fixed reference metric frame and antenna position in fore part.

18 Annex, page 14 The EGNOS status alert mark is designed to inform the navigator of safe or unsafe situations by the colour codes: green means the Ok. Status, red means the unsafe status. The fig. 6 presents the two possibilities. 1) alert message 2) alert message 3) alert message Figure 6: The figurative presentation of EGNOS integrity data status in the customized ECDIS. The three types of alerts are expected either individually or simultaneously:.1 Alert based on the fixed limit values: activated if circular protection level HPL (derived solely from GNSS / SBAS) exceeds the horizontal alert limit HAL set for a specific marine area and operation..2 Alert based on the domain methodology: activated if there are dangers to navigation inside the constructed MVPA. The MVPA can be of variable size depending on the coverage k-factor (relevant to the integrity risk) set for a specific marine area and operation (optional for the future implementation). The rationale for the k-factor comes from the assumption of uncertainty normal distribution in both the North and the East directions of position ordinates..3 Alert based on the age of integrity data: activated if the age of EGNOS integrity data exceeds time to alert limit (t EGNOS). B. The operational zones defined in [RD-3] i.e. ocean, costal, port approach, port, inland waterways should be kept, and their parameters (accuracy, HAL and integrity risk) could be set even to the most severe ones of port areas (according to the measurement campaign EGNOS meets these criteria). The detailed IMO criteria of system level parameters for various ship operations must be further evaluated via ship specific simulations.

19 Annex, page REFERENCES [RD-1] [RD-2] [RD-3] [RD-4] [RD-5] [RD-6] [RD-7] [RD-8] [GSA SDD] [GSA SDD] OS SoL [IMO A.915(22)] [IMO A.1046(27)] [MSC] [RTCA MOPS] [Zalewski IAIN] [Heßelbarth ISIS-MTE] The European GNSS Agency (GSA): EGNOS Open Service (OS) Service Definition Document, Rev. 2.1, 2014 The European GNSS Agency (GSA): EGNOS Safety of Life (SoL) Service Definition Document, Rev. 3.0, 2015 IMO: Revised Maritime Policy and Requirements for a Future Global Navigation Satellite System (GNSS), Resolution A.915(22) from 22nd Session of the Assembly of International Maritime Organization, adopted on 29 November 2001, London, IMO: A.1046(27): WORLDWIDE RADIONAVIGATION SYSTEM, 2011 IMO: MSC Performance standards 112(73), 113(73), 114(73), 115(73), 233(83), 252(83), 379(93) RTCA, Inc. SC-159: RTCA DO-229D Minimum Operational Performance Standards (MOPS) for Global Positioning System / Satellite Based Augmentation System Airborne Equipment, 2006, Change 1, 2013 Zalewski P., Gucma L., Born A., Urbanska K., Schlueter S., Porretta M.: Assumptions of Full Mission Ship Bridge Simulation Including EGNOS, Proceedings of 2015 International Association of Institutes of Navigation World Congress, Prague, Czech Republic, October A. Heßelbarth, S. Gewies, T. Noack, P. Zalewski, L. Gucma, K. Urbanska, S. Schlueter, M. Porretta: EGNOS-based positioning performance for nautical tasks and the potential of implementation in the maritime domain, Proceedings of ISIS MTE 2016, Hamburg, Germany, 31 August to 02 September 2016