Analytic Distribution Design for Irregular Repetition Slotted ALOHA With Multi-Packet Reception

Associated with multi-packet reception at the access point, irregular repetition slotted ALOHA (IRSA) holds a great potential in improving the access capacity of massive machine type communication systems. This work investigates the packet repetition of the users in an IRSA-based random access system where the access point can simultaneously retrieve multiple packets in a slot. Specifically, we propose an analytical transmission probability distribution for IRSA with
dual-packet reception capability
. In addition, the energy efficiency optimization in terms of the maximum number of replica is also presented. Numerical results show that using the proposed transmission distribution for the replica can achieve a significant higher throughput than the existing benchmark distributions. With optimized repetition rate, the energy efficiency of users can be also improved remarkably.