A Decentralized Framework for Dynamic Downlink Base Station Cooperation

Abstract

Multiple Base Station (Multi-BS) cooperation has been considered as a promising mechanism to suppress co-channel interference and boost the capacity for cellular networks. However, the large feedback and signaling overhead hinder it from practice. Therefore, limited cooperation among BSs is recognized as a good tradeoff between the performance gain and the relevant cost. In this paper, the whole network is divided into small disjointing BS cooperation groups, namely, clusters. A decentralized framework is proposed to facilitate the BS cluster formation on the downlink, in order to maximize the sum-rate of the scheduled mobile stations (MSs) under the cluster size constraint. Moreover, an efficient BS negotiation algorithm is designed for cluster formation, of which the feedback overhead per MS is irrelevant to the network size, and the number of iteration rounds scales very slowly with the network size. Simulations show that our strategy leads to significant sum-rate gain over static clustering and performs almost the same as the centralized greedy approach. With its low signaling overhead and complexity, the proposed framework is well suited for implementation in large-scale cellular networks.