Practical decentralized high-performance coordinated beamforming

Abstract

Coordinated Beamforming (CBF) has been studied in hope of mitigating the inter-cell interference experienced by cell-edge users. Unfortunately, due to the limitations and/or impracticalities of the proposed designs, the expected performance gains have yet to be realized. In this work, a decentralized framework (and various example designs) is proposed for the practical transceiver and signaling design of a K-pair system desiring to employ CBF. Relying on channel soundings from the users and equivalent channel soundings from the cell sites (all on the same frequency), the optimum performance of centralized interference alignment designs is achieved (if not surpassed) when each pair's number of data streams is equal to its user's number of antennas. In addition, higher sum capacities than the generalized iterative approach, a centralized MMSE CBF design, are numerically observed. Clearly, practical CBF designs which can deliver the expected performance gains are finally available.