Modeling, Analysis and Optimization of Multicast Device-to-Device Transmissions

Multicastdevice-to-device (D2D)transmission is important for applications like local file transfer in commercial networks and is also a required feature in public safety networks. In this paper we propose a tractable baselinemulticast D2Dmodel, and use ittoanalyze importantmulticast metrics like the coverage probability, mean number of covered receivers and throughput. In addition, we examine how themulticast performance would be affected by certain factors like dynamics (dueto e.g. mobility) and network assistance. Take the mean number of covered receivers as an example. We find that simple repetitivetransmissions help but the gain quickly diminishes as the number of repetitions increases. Meanwhile, dynamics and network assistance (i.e. allowing the networkto relay themulticast signals) can help cover more receivers. We also explore howto optimize multicasting, e.g. by choosing the optimalmulticast rate and the optimal number of retransmission times.?