Abstract: Systems and methods for interference and/or power reduction for multiple relay pairs using cooperative beamforming are provided. A method of operation of a network node in a cellular communications system includes determining beamforming weights for multiple subchannels for each of multiple relay nodes such that a parameter is minimized. The parameter is a maximum per subchannel interference and/or per relay power usage. Determining the beamforming weights includes determining a dual problem of the minimization of the parameter where a solution maximizing the dual problem will minimize the parameter; reformulating the dual problem into a semidefinite programming (SDP) problem; and determining if signal-to-noise ratio (SNR) constraints are active. If the SNR constraints are all active, the method includes determining optimal beamforming weights a first way and if the SNR constraints are not all active, determining optimal beamforming weights a second way.

Abstract: Systems and methods for interference and/or power reduction for multiple relay pairs using cooperative beamforming are provided. A method of operation of a network node in a cellular communications system includes determining beamforming weights for multiple of subchannels for each of multiple relay nodes such that a parameter is minimized. The parameter is a maximum per subchannel interference and/or per relay power usage. Determining the beamforming weights includes determining a dual problem of the minimization of the parameter where a solution maximizing the dual problem will minimize the parameter; reformulating the dual problem into a semidefinite programming (SDP) problem; and determining if signal-to-noise ratio (SNR) constraints are active. If the SNR constraints are all active, the method includes determining optimal beamforming weights a first way and if the SNR constraints are not all active, determining optimal beamforming weights a second way.