This paper addresses the problem of coordination on the interference channel (IC), which has attracted a lot of attention in the research community recently. More precisely, coordinated beamforming is considered, in a multi-cell/link environment where base stations equipped with multiple antennas each attempt to serve a separate user despite the interference generated by the other bases. With single antenna users, this corresponds to the so-called MISO IC considered among others in [1, 2]. In this paper, we propose a distributed approach for designing the beamforming vectors to be used at the transmitters, which relies only on local channel state information (CSI) at each base. The technique exploits a metric which is reminiscent of the virtual uplink method proposed in [1]. We demonstrate analytically the optimality of the proposed approach in terms of achieving the outer bound of the rate region in certain cases. We conduct simulations showing the gains for general settings.
