Outage Rate Regions for the MISO Interference Channel: Definitions and Interpretations

We consider the slow-fading two-user multiple-input single-output (MISO) interference channel (IC), where the receivers treat the interference as additive Gaussian noise. We study the rate points that can be achieved, allowing a non-zero outage probability. The points which meet the outage probability specification constitute a so-called outage rate region. There exist several definitions of the outage rate regions for the IC, as for the broadcast and the multiple-access channels. We give four definitions for the outage region of the MISO IC. The definitions differ on whether the rates are declared in outage jointly or individually and whether there is instantaneous or statistical channel state information (CSI) at the transmitters. For the statistical CSI scenario, we discuss how to find the outage probabilities in closed form. We provide interpretations of the definitions and compare the corresponding regions via analytical and numerical results. Index Terms Beamforming, interference channel, MISO, outage probability, rate region