The effect of out of cluster interference on coordinated beamforming in LTE-A HetNets

Coordination is foreseen to be an important component of future mobile radio networks. It is especially relevant in heterogeneous networks, where high power base stations produce strong interference to an underlying layer of low power base stations. This work investigates the impact of the interference from base stations which are not part of the cooperation. This interference is called out of cluster interference. The practical implications of out of cluster interference are investigated in a realistic implementation of cooperation through coordinated beamforming. As a key result the relationship between the amount of out of cluster interference and the performance in the network is shown. Detailed simulation analysis is presented on a realistic network layout. Comprehensive system-level LTE-Advanced simulations were used to show which network layouts are suitable for the coordination.