CMA and Soft Decision-Directed Scheme for Semi-Blind Beamforming of QAM Systems

— We propose a semi-blind adaptive beamforming approach for wireless systems that employ high-throughput quadrature amplitude modulation signalling schemes. A minimum number of training symbols, equal to the number of receive antenna-array’s elements, are first utilised to provide a rough initial least squares estimate of the beamformer’s weight vector. A concurrent constant modulus algorithm and soft decisiondirected scheme, originally developed for single-user blind channel equalisation, is then applied to adapt the beamformer. It is demonstrated that this semi-blind adaptive beamforming scheme is capable of converging fast to the minimum mean-square-error beamforming solution.

• Type: Conference
• Year: 2008
• Where: VTC
• Authors: Sheng Chen, Wang Yao, Lajos Hanzo
• Keywords: Adaptive Beamforming Approach, Adaptive Beamforming Scheme, Communications, Semi-blind Adaptive Beamforming, VTC 2008