An efficient feedback and scheduling scheme for cooperative multiple-point transmission in heterogeneous networks

Cellular networks are evolving towards a mixture of macro cells and small cells, thereby increasing the number of cell sites to serve traffic hotspots. This trend poses challenges for managing inter-cell interference and traffic offloading, since a multitude of transmitters of different power classes creates imbalance between the downlink and uplink coverage. Conventional network planning and interference randomization techniques offer limited protection in such environments. Recently standardized semi-static inter-cell coordination strategies provide some capability for interference avoidance. This paper presents a scheme for dynamic coordination of the interference using cooperative multi-point transmission techniques in heterogeneous networks. The scheme relies on an efficient feedback technique coupled with a scheduling algorithm which dynamically handles inter-cell interference and traffic offloading between cell layers.