Efficient beamforming algorithms for MIMO multicast with application-layer coding

A communication scheme for the multiple antenna multicast fading channel is proposed, in which the transmission is coded at the application layer over a number of channel realizations. The scheme gives rise to a novel multicast transmit beamforming problem. The properties of the proposed scheme are presented, in particular the scaling of the achievable rate for the increasing number of users is investigated and the rate is shown not to decrease to zero, which is an improvement over multicast schemes without coding, e.g. so-called max-min transmit beamforming. Algorithms for solving the resulting beamforming problem are proposed and evaluated in simulation.