Femtocell networks: Breaking the complexity of centralized processing with novel dual-stage receivers

In this paper, we consider femtocell networks and focus on interference mitigation in a novel framework referred to as FemtoWoC architecture (Wireless over Cable architecture for femtocells) [1]. This framework enables centralized processing (joint decoding) of multiple femto base stations at a central place termed as femto control station (FCS). The full blown up maximum likelihood centralized decoding at FCS will go beyond any acceptable limits. This paper proposes a novel dual-stage receiver architecture which achieves the tradeoff of centralized processing (joint decoding) and complexity. The basic idea is two folds, i.e. using some linear processing to reduce the dimension of the femtocell system followed by some nonlinear processing to exploit dominant interferences. The resultant multi-stage receiver is characterized by the performance closer to that of an optimal receiver but with much less complexity.