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. Considering the time-frequency resource efficiency, K = 2 (multi-packet reception capability) may be the most suitable scheme for scenarios that allow smaller resource efficiency in exchange for greater throughput. In this paper, we analytically derive an optimal transmission probability distribution for IRSA with K = 2, which achieves a significant higher load threshold than the existing benchmark distributions. In addition, the energy efficiency optimization in terms of the maximum repetition rate is also presented.

翻译：与进入点的多包接收相关联,不规则的重复时间档ASOHA(IRSA)在提高大规模机器型通信系统的接入能力方面具有巨大潜力,考虑到时间-频率资源效率,K=2(多包接收能力)可能是使资源效率较低以换取更大输送量的最为合适的设想方案。在本文件中,我们分析得出IRSA与K=2的最佳传输概率分布,后者的负荷阈值比现有基准分布值高得多。此外,还介绍了最高重复率方面的能源效率优化。