Interference robustness for cellular MIMO networks

Abstract

Uncertainty in the spatial signature of interfering signals is a major source of performance degradation in the downlink of a MIMO network. In general, the exact transmit covariance matrix of the other transmitters can not be predicted correctly in advance as the optimal strategies mutually depend on each other. In this work, we investigate two approaches for optimizing downlink transmission that are robust to interference, while operating in absence of cross channel information at the transmitter. Although they may seem unrelated, the two approaches share an interesting symmetry and are both derived from a more general minimax duality.