In-situ monitoring using nano-satellites : a systems level approach

Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2015.Traditional satellite systems employed for use with in-situ monitoring systems are large satellites that have a long development time, high cost and complex sub-systems. The end use of relaying data for in-situ monitoring becomes a costly application for the end user. Shifting this application to make use of nano-satellites, such as CubeSats, for data relaying will make the application more attractive to the end user when measurements are required outside existing ground based communications infrastructure. CubeSats are small, simple satellites that yield a short development time and very low cost compared to conventional satellites. Their sub-systems are generally built from off the shelf components. This keeps the designs simple, manufacture cost low with the potential for flying the latest technologies. This research set out to analyse various scenarios related to in-situ monitoring governed by parameters such as the maximum revisit time, satellite orbit altitude, quantity of sensor nodes and data quantity relayed in the system. A systems level approach is used to analyse each designed scenario using a simulation tool called Systems Tool Kit by Agilent Graphics Incorporated. The data acquired for each scenario through simulation was validated using theoretical approximation methods, which included parameters such as coverage potential, total node access time, communication link performance, power resources, memory resources, access time and number of ground stations. The focus was put on these parameters since they are the main constraints when designing a system using nano-satellites. The outcome of the research was to create an analysis reference for designing an in-situ monitoring system using nano-satellites. It outlines the methods used to calculate and simulate each of the constraints governing the system. Each designed scenario showed satisfactory performance within the defined parameters and can be practically implemented as a reference for designing similar systems.National Research FoundationSouth African National Space Agenc