Satellite-Based Radio Spectrum Monitoring: Architecture, Applications, and Challenges

Radio spectrum monitoring provides essential information about actual frequency spectrum usage to support the spectrum management process. The conventional strategy of spectrum monitoring relies on the deployment of terrestrial spectrum monitoring networks. However, performing large-scale radio spectrum monitoring on the ground is a great challenge, hampered by the limited monitoring coverage and complex geographic environment. In this article, we present a space spectrum monitoring framework by using small satellites in low Earth orbit. It can greatly expand the monitoring coverage to a global scale and flexibly determine the locations of interference sources. Moreover, it can significantly promote international frequency coordination and spectrum sharing in future wireless networks. We first introduce the architecture and analyze the feasibility of the proposed system, and then present key application scenarios. Finally, we identify the main challenges and future directions.