Optical Communication Payloads: Analysis for Sustainable Satellite Constellations

Abstract

Global connectivity, high-speed and reliable transfer are the current development goals of the space communication sector. An approach by German Aerospace Center (DLR) to fulfil these requirements is done by investigating the feasibility and economy of combining globally attainable satellite constellations, with optical communication, which is reliable and has high data rates. Designing a constellation with the constraint of optical Inter Satellite Links (ISLs) motivates for the evaluation of different factors regarding the suitability of different constellations. In this work, the environmental impact, orbital pollution, and costs are compared for multiple constellation archetypes while considering transmission performance in terms of latency. These constellations vary in terms of satellite quantity, size, and altitude. Two trade studies are conducted to obtain the most suitable constellation. The first trade study executes a qualitative analysis, identifying the three most promising ones. The final three are analysed quantitatively using a second trade study. Each trade factor is quantified, normalised, and weighted to achieve comparable results. The developed Python tool which performs the trade study returns and visualises the results. It allows the visualisation of uncertainty and sensitivity studies for the results and enables further extensions and optimisations for follow-up work.