GDT 2.0: design, development and testing of algorithms for Galileo System Data Analysis

The purpose of this paper is to document the activity carried out by the company AKKA Italia s.r.l. for the project GDT 2.0, included in the program of Galileo Satellite System Management. The GDT project aims to develop and to improve algorithms for monitoring the state of activity of the Galileo system. The GDT is a set of diagnostic “analyses” each of which is composed of several SW modules. Most analyses work with positioning data and all produce data which is exported in .CSV format, HTML reports with tables and figures in .PNG format. Then there is a subset, that are called statistical analyses, where the data exported from the other analyses are used to compute statistical operations. Given the complexity of this project a team of numerous colleagues was formed, each focusing on a particular aspect. My role was to implement algorithms for some analyses which will impact on certain SW modules. In particular, my activity was mainly characterized by: design and implementation of a Log File system, added to all the GDT analyses, to monitor the activity status after each run; implementation of a function that would allow the export in .CSV format of some quantities of interest; design and implementation from zero of a new SW modules, called Post Processing, which will interact directly with the exported quantities in .CSV to perform statistical operations on them. Finally, the last activity on the SW was linked to the changes of the Ingestion module to manage the input of SiS Raw Data files (in binary format, coming directly from low-level components of the Galileo System). After these implementations I took care of a testing phase on the code of all GDT tool. These phases are made necessary by the guidelines which guarantee the safety, security and reliability of all software projects of the Galileo program and which take the name of "Galileo SW Standard" (GSWS). All the software was written in IDL (Interactive Data Language). The test campaign on SW developed was done in the Quadas environment. Quadas is a tool, with dedicated MMI, used by the user for interaction with the SW modules developed. The development of the GDT tool followed the life cycle of a software product, and for this reason the main phases addressed during the work were: documentation and design, development, testing, validation and integration. First of all an Introduction to the Galileo System is presented. This was necessary to fully understand the origin of the data with which I was going to work. Then, the Quadas tool has been studied in depth, in order to understand which were its features with respect to analyses and algorithms to develop. Also the GDT, in its previous version, has been analyzed and described in detail. This description is essential to contextualize the new implementation requirments received by the customer. All modules and new functions developed are described in a dedicated chapter and each one is introduced by a brief description of new SW requirements. Then, before presenting the test phase, with the consequent validation of the SW produced, each algorithm and SW module developed will be deepened. Finally, the whole test campaign performed on the SW is presented and all results obtained will be discussed. This product fits into the aerospace scenario, which has always been at the heart of innovation and technological development. For this reason, it is not to be excluded a new implementation phase on the GDT tool, so as to make it more current and performing.