Cooperative Downlink Transmission Mode Selection Under Limited-Capacity Backhaul
Coordinated Multi-Point transmission (CoMP) has been widely recognized as a promising technique for improving spectral efficiency in future cellular systems. However, it may require high-capacity backhaul links, which can increase expense. In this paper, the authors study the cooperative transmission method with limited-capacity backhaul. Downlink CoMP transmission requires the exchange of information between base stations, depending on the type of CoMP schemes. Either Channel State Information (CSI) information of all users (for coordinated beamforming), or both data and CSI (for joint processing) need to be shared among all cooperative base stations.