Guiding blind transmitters for K-user MISO interference relay channels with Imperfect channel knowledge

This paper proposes a novel multi-antenna relay-aided interference management technique that can use imperfect channel knowledge for interference relay channels. Using the proposed method, it is shown that KM/K+M-1 degrees of freedom (DoF) are achievable in a K-user multiple-input-single-output interference relay channel when the relay has M antennas with a certain type of limited channel knowledge. By leveraging this result, it is demonstrated that the interference-free DoF of K are asymptotically achieved as M approaches infinity. One major implication of these results is that even under this limited channel knowledge, the use of massive antennas at the relay is sufficient to recover the optimal DoF for relay-aided interference networks with perfect channel knowledge.