Energy-Efficient Irregular Repetition Slotted ALOHA for IoT Satellite Systems

There is an urgent need to enhance random access schemes, specifically designed to support massive Internet of things communications in satellite systems. These scenarios are limited by two key factors: the lifespan of device batteries and the scarcity of satellite resources. To overcome such limitations, we propose to apply per replica power diversity to irregular repetition slotted ALOHA protocol. We evaluate the protocol performance in terms of energy and spectral efficiency. We provide an asymptotic analysis to track the decoding process at the satellite, and complement our study by means of simulations to explore the finite frame length case. In both settings, the proposed scheme triggers significant and promising improvements with respect to the state of the art.