Jamming Scheduling and Resource Allocation for Secure Communication in Massive LEO Satellite-Empowered IoT Network

The massive low Earth orbit (LEO) satellite-empowered Internet of Things (MLS-IoT) network has many advantages, including high capacity, low latency, large network coverage, and high reliability. However, the openness and broadcasting on satellite communication links pose huge challenges to protecting the security of data delivery, especially to defend against eavesdropping. Leveraging the density of LEO satellite deployment and developing efficient secure communication schemes with the aid of physical layer security (PLS) techniques deserves further exploration. To the best of our knowledge, it is an almost untouched issue to employ satellites to transmit a jamming signal in MLS-IoT systems since lots of available research in this line mainly considered cooperative jamming only on ground networks. For this purpose, we propose in this article a PLS-based secure communication enhancement scheme in the MLS-IoT network. A jamming scheduling and resource allocation problem is presented for the secrecy rate maximization by dynamically switching the roles of satellites on subchannels for transmitting private information or a jamming signal. An iterative strategy is devised to jointly optimize jamming scheduling, device association, channel assignment, and power allocation. Numerical results validate that our presented optimization approach could significantly improve the system secrecy rate and achieve the optimal jamming scheduling and resource allocation decisions.