<div>FrontierSI has been engaged by Geoscience Australia (GA) to establish a series of case studies showcasing the benefits of Positioning Australia products and services through demonstrations of precise positioning capability. This case study is the third in the series and in a collaboration with The Commonwealth Scientific and Industrial Research Organisation&nbsp;(CSIRO) it aims to explore the use of Ginan’s real-time and post-processing capabilities for determining water level height from a global navigation satellite systems (GNSS) receiver deployed on a floating pontoon on Googong Dam.</div>

<div>FrontierSI has been engaged by Geoscience Australia (GA) to establish a series of case studies showcasing the benefits of Positioning Australia products and services through demonstrations of precise positioning capability. This case study is the second in the series and in a collaboration with The Bureau of Meteorology (BOM) it aims to explore the use of Ginan’s post-processing capabilities for determining receiver altitude and atmospheric parameters from global navigation satellite systems (GNSS) observations collected from a high-altitude balloon.</div>

<div>FrontierSI has been engaged by Geoscience Australia (GA) to establish a series of case studies showcasing the benefits of Positioning Australia products and services through demonstrations of precise positioning capability. The Australian Institute of Marine Science (AIMS) was selected as the demonstration partner for this case study, contributing their extensive knowledge of current and future marine technologies and providing a suitably challenging environment for deployment of precise positioning solutions. This project investigates the available options for provision of precise global navigation satellite systems (GNSS) positioning at the AIMS Marine Operations Centre, and explores the suitability, benefits, and challenges of using Positioning Australia products including Ginan for this purpose.&nbsp;</div>

<div>Australia has been supporting 13 Pacific Island countries (PICs) to measure, record and analyse long-term sea level and land motion for over 25 years. This is known as the Pacific Sea Level and Geodetic Monitoring (PSLGM) project which is funded by Australian Aid under the Climate and Oceans Support Program in the Pacific (COSPPac). </div><div>The sea level data is collected continuously at one or two tide gauges in each of the 13 PICs. The land motion data is collected continuously at one or two Global Navigation Satellite System (GNSS) stations in each of the 13 PICs. The height difference between the tide gauges and GNSS stations is observed once every 18 months (approximately). The data is then analysed to produce sea level information-based products (e.g. tide calendars) and to inform about motion of the land (e.g. for coastal infrastructure planning). </div><div>The PSLGM project involves Australian science agencies (Bureau of Meteorology (Bureau) and Geoscience Australia (GA)) working in partnership with regional organisations (Pacific Community (SPC)), and Pacific government ministries (meteorology and land and survey departments).</div><div><br></div><div>This GA Record reports findings regarding the absolute vertical rate of movement (i.e. the rate at which the land is moving up or down with respect to the centre of the Earth) of 13 Pacific Island Countries tide gauges over the period 2003 – 2022 based on the analysis of Global Navigation Satellite System (GNSS) data and levelling data.&nbsp;&nbsp;</div><div><br></div>

<div>Ginan is a GNSS (Global Navigation Satellite System) analysis centre software that is currently being developed by Geoscience Australia in partnership with industry and academic partners. Ginan is fully open-source software based on the SSR (State Space Representation), PPP (Precise Point Positioning) model and is capable of computing precise positioning products, delivering real-time correction services, as well as operating as a user-driven precise positioning engine.</div><div><br></div><div>Ginan is a modern, multi-threaded C++ application that utilises industry standard high-performance libraries such as Eigen3, and Boost. Software configuration is managed through industry standard YAML (YAML Ain’t Markup Language) files. Standard IGS (International GNSS Service) file-based products are produced, and intermediate positioning products are managed in the open-source NoSQL MongoDB database and output is through standard Radio Technical Commission for Maritime Services-3 (RTCM3), IGS-SSR and Compact SSR message streams. At its core, Ginan is a customised and optimised Kalman filter that is tightly coupled with a data pre-processor and orbit integrator, enabling both real-time processing of industry standard RTCM3 data messages streams and post-processing using IGS positioning products.</div><div><br></div><div>The purpose of Ginan is to provide users with a unique multi-GNSS real-time processing platform capable of delivering precise positioning products to the Australian and international Positioning Navigation and Timing (PNT) community; support expert advice on navigation system performance over Australia; and provide state-of-the-art GNSS analysis centre software to universities and research organisations to enable Australia to lead in the development of geospatial technology. Ginan can be used for many geodetic and positioning activities such as computation of daily coordinate solutions, precise satellite orbit determination, computation of satellite clocks & biases, atmospheric modelling, data QA/QC and more. This paper describes the Kalman filter optimization methodology implemented in Ginan and provides benchmarking comparisons of Ginan against the International GNSS Service combined orbit and clock products. Abstract presented at the 2024 Institute of Navigation (ION) Pacific Positioning, Navigation and Timing (PNT) Conference Honolulu, Hawaii