Popis: |
Mega-constellations are one of the emerging challenges in the satellite communication business. Several concepts of large networks of inexpensive low Earth orbiting satellites have been proposed in response to the ever increasing demand for low cost broadband capacity, particularly in developing countries where there is limited access to terrestrial networks. In this context, mega-constellation satellite reliability is identified as a key aspect in-view of the potential catastrophic impact on the space debris environment if satellites fail to deorbit given the large number of satellites involved. However, predicting reliability without having a detailed design is a challenging task as bottom up analyses using handbook based methods are not possible. Moreover, there are many inadequacies and limitations with the current reliability prediction process for space applications. Secondly, the available field data regarding low Earth orbit (LEO) satellites may not be representative due to the revolutionary design, manufacturing, and testing approach proposed by the mega-constellation satellite suppliers. Finally, all this leads to a large uncertainty in the predicted reliability of mega-constellation satellites with a consequential risk to the space environment. In order to address the situation, the authors have identified a number of potential solutions to mitigate the risk including design measures, operational procedures, and improvements to the reliability assessment process. |