User position aware multicell beamforming for a distributed antenna system

Implementing a distributed antenna system (DAS) improves system capacity and reduces transmit power. One challenge in a DAS is intercell interference due to simultaneously supporting multiple users with the same carrier frequency. We propose a multicell beamforming (MBF) technique to remove intercell interference amongst coordinated cells within a DAS. As the MBF technique requires circulations of users´ data amongst groups of cells, we introduce a user position aware (UPA) MBF algorithm to reduce backhaul burden. Our proposed UPA MBF scheme guarantees a consistent quality of service to users irrespective of their locations within a cell with minimum total transmit power across base stations of a DAS. An effective sum rate formula is also derived to evaluate the backhaul effects on these schemes.