In this paper we propose the design and prototype results of a hybrid optical and radio communication architecture developed to fit the coarse pointing capabilities of nanosatellites, tested through a proxy flight experiment on stratospheric balloons. This system takes advantage of the higher data-rate offered by optical communication channels while relying on the more mature and stable technology of conventional radio systems for link negotiation and low-speed data exchange. Such architecture allows the user to overcome the licensing requirements and scarce availability of high data-rate radio frequency channels in the commonly used bands. Outlined are the architecture, development and test of the mentioned terminal, with focus on the communication part and supporting technologies, including the navigation algorithm, the developed fail-safe approach, and the evolution of the pointing system continuing previous work done in 3. The system has been built with commercial-off-the-shelf components and demonstrated on a stratospheric balloon launch campaign. The paper outlines the results of an in-flight demonstration, where the two platforms successfully established an optical link at stratospheric altitudes. The results are then analyzed and contextualized in plans of future work for nanosatellite implementations. |
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