Performance Analysis of Coded Slotted ALOHA in a Cell-Free Scenario Using Stochastic Geometry

Grant-free access schemes, which help reduce control signalling and simplify device design, are strong candidates for enabling future massive multiple access scenarios. At the same time, cell-free architectures offer a promising path toward achieving fairness in both power consumption and user performance. The integration of these two approaches holds significant potential for efficiently connecting large numbers of low-power devices to the network. In this paper, we develop a theoretical framework for grant-free coded random access with successive interference cancellation in the context of cell-free architectures, leveraging tools from stochastic geometry and density evolution. We analyze the advantages that can be obtained when the packets are not just repeated, but are first splitted in subpackets and then encoded by a small code. This Coded Slotted ALOHA approach allows higher coderates, with a potential energy saving w.r.t. the use of repetitions.