Design of Control Architecture for Downlink CoMP Joint Transmission with Inter-eNB Coordination in Next Generation Cellular Systems

CoMP (Coordinated Multiple Point transmission) is being discussed in 3GPP (3rd Generation Partnership Project) to improve the cell edge performance as well as the total cell throughput of mobile systems. In this paper, we focus on the control architecture to realize downlink CoMP JT (joint transmission) with inter eNB (evolved NodeB) coordination. We have designed the control architecture with a distributed approach. Since user data is simultaneously transmitted from multiple eNBs to a UE (User Equipment), the schedulers of the coordinated eNBs need to negotiate on resource allocation for CoMP UEs over a backhaul network. This process will be a heavy burden due to the delay of the backhaul network and the complexity of scheduling algorithm that has to take into account a dynamic multi-UE and multi-cell scenario. We propose a simple and practical resource allocation method by which the scheduler in each eNB can make scheduling calculation independently without any resource contention. We also implement the proposed schemes as a real system for evaluation.