Fractionated space infrastructure for long-term earth observation missions

Abstract

A fractionated spacecraft is a space system that distributes its functionalities, such as computation, communication, data storage, payload and even power generation, over several independent satellite modules that share those functionalities through a wireless link. This paper exploits this innovational architecture to design a space infrastructure that is able to accept and support multiple Earth Observation (EO) payload modules. In this paper the functional, physical and organizational architectures of the infrastructure are presented. To start with, EO programs utilizing monolithic spacecraft especially SPOT and Landsat programs are reviewed and analyzed to derive the inherent EO functional requirements. Then these functional requirements are integrated into an EO scenario based on a reference orbit typically for EO missions. Next, novel architectures of fractionated spacecraft are reviewed and the inherent non traditional attributes are summarized and classified in such a way to show their close interrelation with the EO functional requirements. Then four resources components: high bandwidth downlink component, data relay satellite communication component, mission data processor component and large volume data storage component are identified and designated to establish the EO space infrastructure. Based on those four components different physical architectures are designed for the specific scenario and then are evaluated using the Analytical Hierarchy Process (AHP) with eight selection criteria. Afterwards, the best option has been identified, which comprises four heterogeneous modules assigned to host those four resources components separately. Finally, this physical architecture is organized by means of the Multi-Agent System (MAS) theory, which fulfills best the EO non traditional requirements. The proposed organization is tailored for the autonomous operations of the fractionated infrastructure and is based on the peer-to-peer architecture. From a physical and organizational perspective, the developed space infrastructure is able to self-adapt, self-optimize and self-configure to dynamic changes in various local environmental conditions.