Decentralized target rate optimization for MU-MIMO leakage based precoding

In this paper we propose a decentralized target rate precoding for multi-user multiple-input multiple-output downlink setups. It is well suited for joint transmission and works for arbitrary cooperation sets. The precoding is optimized for each link separately with respect to the transmit and leakage power. This allows to control the interference into the network and to design the precoding flexibly with respect to energy efficiency and outage minimization. A closed form solution for the optimization problem is presented and the trade-off between the used transmit power and generated leakage power is discussed. Based on the proposed target rate precoding, different strategies for the iterative optimization of a network are presented and evaluated in numerical simulations.