Author : Esther Bermejo Dalmau
Publisher :
Page : pages
File Size : 42,21 MB
Release : 2012
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ISBN :
This project aims to analyze space radiation effects on the electronic components of WikiSat, the femto-satellite developed at EETAC. We present a further development of the project presented by Laia Molas Pous, in which radiation effects on electronic components at 28o inclination Low Energy Orbits (LEO) were considered. In this case we study a similar altitude range but focus on polar inclination orbits. This way we expose our model components to a much more hostile radiation space environment. The main tool we use is SPENVIS, the software developed by the European Space Agency (ESA) that allows the computation and analysis of space radiation characteristics and effects on biological and electronic components orbiting around the Earth. Using SPENVIs we define 80o LEO orbits at different altitudes and compute particle fluxes and fluencies, magnitudes that characterize space radiation due to trapped electron and protons, solar particle events and cosmic radiation. SPENVIS also allows us to model the components of the electronic device we intend to study and two different types of battery and the shielding properties of polyethylene and lead. Finally, we analyze the interaction between the radiation environment at the polar LEOs defined above and our model device and batteries. We present the values of total ionizing doses (TID), which characterize an important part of the expected damage on systems exposed to radiation. As expected, the obtained TID values, are above the threshold that would allow a reliable performance of the electronic devices considered. Nevertheless, we show quantitatively that the MEMS with one of the proposed batteries and with the shielding layers of lead or polyethylene accumulate TIDs only about one order of magnitude above the safety threshold of 1 mrad. This result supports the viability of a femto-satellite like WikiSat operating near polar orbits, provided a careful choice of electronic devices more resistant to radiation and the implementation of a basic radiation shield.