Reliability Analysis of mMTC Slotted ALOHA Systems Under Finite-Length Constraints

In this work, we consider the probability that a short-length data packet originating at an Internet of Things (IoT) device is successfully delivered at a nearby base station using slotted ALOHA (SA) random access in the presence of concurrent and sporadically active IoT devices. Each device maintains a queue and transmits head-of-line (HOL) packets subject to probabilistic retransmissions and a retry limit. To evaluate the reliability of such transmissions, we incorporate a physical-layer model based on Nakagami-m fading and spatially distributed interference, using tools from stochastic geometry.