Optimal Beamforming for Multicasting Data in CMHP

In this paper we show the optimal solution of the beamforming vectors of a multicast setting, in which the transmitter has multiple antennas that sends common data to multiple receivers. We consider two important applications such as the multicasting scenario itself and the use of the common information in a superposition coding scheme known as the Cover-Van der Meulen-Hajek-Pursley´s (CMHP) method. We show that the optimization of the beamforming vector is equivalent to a vector projection problem.