Improving physical layer multicast by cooperative communications in heterogeneous networks

Recently, heterogeneous networks (HetNets) have drawn significant attention from academia and industry as an efficient way to improve the capacity and coverage of cellular systems. In addition to unicast communication, many important applications in HetNets, such as video/audio conferencing and mobile TV, require the support of multicast. In this article, we study the deployment of HetNets from the perspective of cooperative communications to improve the performance of physical layer multicast. Specifically, we coordinate the eNBs of different levels by fountain codes for the data transmission of a multicast session. The fountain codes in cooperative multicast are targeted to the physical layer and have to adopt short code length. Correspondingly, we propose a Reed-Solomon-based approach, which is different from the previous work on application layer forward error correction. Simulation results show that our proposed cooperative scheme can considerably increase the capacity of physical layer multicast in heterogeneous networks.