Very Small Satellite Design for Space Sensor Networks; Doctoral thesis

摘要

An investigation of very small satellite miniaturisation techniques is presented, focusing on sub-kilogram technologies targeted at space sensor network applications. Distributed space mission concepts are emerging for scientific and remote sensing applications. This architecture will enable observation of real-time multi-point phenomena. Space economics and environmental concerns dictate a cost-effective mass-producible low-mass satellite for brief but essential missions in low Earth orbit. Very small satellite technologies have been investigated, assessed, and compared. Two novel design methodologies have been developed, simulated, and verified through functional and environmental testing of hardware. SpaceChip is a monolithic heterogeneous system-on-a-chip integration approach that proves applicable to sensor networks in hostile environments which require simple sensors and sub- kilometre separations. Five prototype chips have been fabricated with promising results. A method has been investigated for on-chip series connection of solar cells yielding a 3.4% efficient system-on-a-chip power supply. Furthermore, a microprocessor design technique was developed that verifies the synergy of radiation hardening by design and asynchronous logic. PCBSat is proposed as a satellite-on-a-PCB miniaturisation approach focused on deriving the smallest practical satellite within context of space sensor networks and use of commercial components, processes, and deployment systems. The concept has been validated by flight model development and test for $10,000 to orbit in quantity. PCBSat emerges as an optimal tradeoff between cost and performance. A case study investigation of ionospheric plasma depletions, known to cause problematic navigation and communication outages, provided a comparison vehicle of all technologies considered in this effort. This research has provided new cost-effective miniaturisation approaches enabling sensor network architectures.