Title :
On the Bottleneck Users for Multiple-Antenna Physical-Layer Multicasting
Author :
Xiaodong Xu ; Baisheng Du ; Chongfa Wang
Author_Institution :
Univ. of Sci. & Technol. of China, Hefei, China
Abstract :
Given the optimal transmit beamforming vector, the user who has the worst signal-to-noise ratio (SNR) is referred to as a bottleneck user for a single-group multicasting system with multiple antennas at the transmit side. In this paper, we present some interesting insights into the bottleneck users, such as the maximum number as well as the optimal beamformer when the transmitter has an arbitrary number of antenna elements. The max-min fair SNR problem is employed and the closed-form solutions are proposed from the weighted sum-SNR maximization perspective for different numbers of possible bottleneck users. A new heuristic beamforming algorithm based on the bottleneck users is also presented to improve the system performance in terms of the achievable rate for physical-layer multicasting.
Keywords :
antenna arrays; array signal processing; multicast communication; radiocommunication; transmitting antennas; antenna elements; closed-form solutions; heuristic beamforming algorithm; max-min fair SNR problem; multiple-antenna physical-layer multicasting; optimal transmit beamforming vector; signal-to-noise ratio; single-group multicasting system; weighted sum-SNR maximization; wireless communication systems; Array signal processing; Closed-form solutions; Multicast communication; Signal to noise ratio; Transmitting antennas; Upper bound; Vectors; Bottleneck user; Physical-layer multicasting; bottleneck user; closed-form solution; physical-layer multicasting; transmit beamforming;
Journal_Title :
Vehicular Technology, IEEE Transactions on
DOI :
10.1109/TVT.2013.2296335