Design of Single-Group Multicasting-Beamformers

— For the single-group multicast scenario, where K users are served with the same data by a base station equipped with N antennas, we present two beamforming algorithms which outperform state-of-the-art multicast filters and feature a drastically reduced complexity at the same time. For the power minimization problem, where QoS constraints need to be satisfied, we introduce a successive beamforming filter computation approach aiming at satisfying at least one additional SNR constraint per orthogonal filter update. As long as the number of users K is smaller than the number N of transmit antennas, this procedure delivers excellent results. Our second approach is an iterative update algorithm for the max-min problem subject to a limitation of the transmit power. Given a low-complexity initialization beamformer, we search within the local vicinity of this filter vector for a filter-update preserving the transmit power and achieving a larger minimum SNR. To this end, we improve the...

• Type: Conference
• Year: 2007
• Where: ICC
• Authors: Raphael Hunger, David A. Schmidt, Michael Joham, Alexander Schwing, Wolfgang Utschick
• Keywords: Communications, ICC 2007, Single-group Multicast Scenario, State-of-the-art Multicast filters, Transmit Power