A New Beamforming Design for Multicast Systems

• Published in: IEEE transactions on vehicular technology Vol. 62; no. 8; pp. 4093 - 4097
• Main Authors: Lee, Wookbong, Park, Haewook, Kong, Han-Bae, Kwak, Jin Sam, Lee, Inkyu
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-10-2013; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Array signal processing; Complexity theory; Convertors; Detection, estimation, filtering, equalization, prediction; Downlink beamforming; Electrical engineering. Electrical power engineering; Electrical machines; Exact sciences and technology; Information, signal and communications theory; MIMO; multicast channels; Multicast communication; multicasting; Radiocommunications; Resource management; Signal and communications theory; Signal to noise ratio; Signal, noise; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Transmission and modulation (techniques and equipments); Transmitters. Receivers; Vectors; Performance evaluation; MIMO system; Downlink beamforming; Parameter estimation; Current source converter; multicast channels; Information rate; Transmitter; Downlink; Algorithm; Power allocation; Computational complexity; Information transmission; Data broadcast; Information dissemination; Beam forming; Multicast; Relaxation; Channel estimation; multicasting; Signal processing; System simulation; Software radio
• ISSN: 0018-9545; 1939-9359
• DOI: 10.1109/TVT.2012.2236583

In this paper, we study a transmit beamforming technique for multiple-input-multiple-output (MIMO) downlink multicast systems. Assuming that channel state information (CSI) is available at a transmitter, we try to maximize the lowest transmit data rate among users for a given transmit power level. Since finding the optimal beamforming vector requires prohibitively high computational complexity, we propose a reduced complexity scheme by applying greedy vector search and a simple power-allocation (PA) algorithm. Simulation results show that the proposed scheme outperforms the conventional semidefinite relaxation (SDR) technique and provides a performance quite close to the optimal performance with much reduced complexity.