This thesis stems from the work done during the internship at Telespazio and its main topic is the study of Link Budget calculation for telemetry, telecommand and ranging signals in satellite communications to analyse the Earth-to-space interface. The main goal was to develop a tool that would autonomously perform all the calculations necessary for margin assessment to determine whether the link is closed or not. This software, implemented with MATLAB, was conceived as an advancement of the tools used by Telespazio, aiming for greater completeness, additional configurations, more complex features, and increased user friendliness, trying to adapt it to any kind of scenario.