Development of cooperative communication techniques for a network of small satellites and CubeSats in deep space: The SOLARA/SARA test case

Abstract

In the last decade, great progress was made in the development of small satellites and CubeSats. Several small spacecraft were designed, fabricated, launched, and successfully operated in low Earth orbit. While more companies and space agencies are becoming interested in CubeSats and small satellite, also the mission goals for these spacecraft are gradually changing: these small spacecraft are starting to be considered for deep-space, interplanetary exploration.Given the limited size, mass and power capabilities of these small platforms, one of the most interesting problems to address is how to develop a communication system to allow small satellites to communicate from very far distance in the solar system.This paper aims to address this problem by proposing cooperative communication approaches in which multiple CubeSats communicate cooperatively together to improve the link performance with respect to the case of a single satellite transmitting. Three approaches are proposed: a beam-forming approach, a coding approach, and a network approach. The approaches are applied to the specific case of the SOLARA/SARA concept: a proposed constellation of CubeSats at the Lunar Lagrangian point L1 which aims to perform radio astronomy at very low frequencies (30kHz to 3MHz). The paper describes the development of the approaches, the simulation and a graphical user interface developed in Matlab which allows to perform trade-offs across multiple constellation׳s configurations.