Development of a tool for Ground to Space Link Budget Computation for several satellites services, with a specific analysis on Lunar Missions.

This thesis, carried out at Telespazio, aims to develop a tool for calculating the link budget across various case studies, capable of meeting all of Telespazio’s current and future needs. The project seeks not only to build a reliable calculation tool, but also to ensure the permanent archiving of the data produced by creating a website that stores and makes all link budgets available for consultation. To this end, Django and SQLite3 were used as the core technologies. The first chapters introduce the theoretical foundations needed to develop the tool, with a focus on the main types of digital modulation, the definition of the ranging signal, modulation losses, and the coding schemes used in communication systems. In particular, a practical approach was adopted for studying modulation losses, performing short loop transmissions to validate the formulas reported in the CCSDS standards. Considerable space is also devoted to analyzing the coding required for telemetry and telecommand systems. In the following chapters, the thesis illustrates step by step the entire link budget calculation flow, integrating all the elements needed for a comprehensive assessment of link performance. Special attention is given to the case of a satellite in lunar orbit, with a detailed analysis of the antenna’s G/T when pointed at the Moon. In the last chapter, the goal is to examine the behavior of the link-budget tool across different case studies. We consider examples of high-rate and low-rate link budgets with parameters similar to those of missions already carried out at Telespazio, to verify that the link closes as expected in my tool as well.