Outage Region Characterization for Beamforming in MISO Interference Networks with Imperfect CSI

We consider an interference network with independent links, whose multi-antenna transmitters have access to an imperfect analog estimate of their local channels. Assuming that the receivers treat the interference as noise, we define the outage rate region as the set of rate-tuples that are achievable with a given probability and we characterize the boundary of the region for transmit beamforming. Our study shows that the Pareto-optimal beamforming vectors judiciously balance the desired signal power and the interference power based on the quality of the estimated channel state. Our analysis further reveals that, in contrast to the well-known results by Jorswieck , for the perfect channel side-information case, transmission at full power is not necessarily Pareto-optimal.