Analysis of Channel Models for LoRa-based Direct-to-Satellite IoT Networks Served by LEO Nanosatellites

There has been increasing interest in the Internet of Space Things (IoST) paradigm, an extension of the traditional Internet of Things (IoT) system based on using satellites to serve terrestrial devices. In particular, the use of nanosatellites to establish direct-to-satellite links provides an attractive, low-cost architecture to achieve actual global coverage for IoT deployments. In this paper, we identify three potential channel models applicable to Direct-to-Satellite IoT networks served by LEO nanosatellites. The methodology used for the selection captures the scenario's specific requirements and allows for direct comparison between the different models. The results obtained via simulations constitute a baseline for future validations with experimental data to arrive at a definitive model for the system under study.