Non-Orthogonal Downlink Transmission for CSS-Based LEO Satellite IoT

With the development of massive access in Internet of Things (IoT) networks, long distance transmission and concurrent techniques have attracted much attention. In this letter, we focus on a concurrent low-earth-orbit IoT network with a chirp spread spectrum (CSS) technique. A new successive interference cancelation (SIC) algorithm that incorporates the CSS properties is proposed. In contrast to the conventional SIC, our proposed algorithm provides less computational complexity. Furthermore, we derive the closed-form expressions for the bit error rate (BER) performance. Finally, both analytical and numerical results substantiate the proximate BER performance compared with the conventional SIC and further investigate the impacts of system parameters on the BER performance.