Optimal Precoder for Rate 1 Space-Time Block Codes

Abstract— Despite primary space-time coding where the channel state information (CSI) is available at the receiver only, the capacity and performance of multiple-input multiple-output (MIMO) systems can be increased significantly when a complete or partial CSI is available at the transmitter. Recently, limited feedback methods including antenna subset selection and unitary precoding have been proposed for orthogonal space-time codes where a partial knowledge of the channel is available at the transmitter via an error-free, zero-delay feedback channel. In this paper, we propose a general structure matrix rather than a unitary one for precoding. By maximizing the signal-to-noise ratio (SNR) per received symbol, we find the optimal precoder for general space-time codes with rate 1 symbol per channel use. The performance of the optimal scheme is analytically evaluated. Next, we extend the result for limited feedback systems. Simulation results show that the proposed precoder outperform...

• Type: Conference
• Year: 2007
• Where: ICC
• Authors: Alireza Ghaderipoor, Chintha Tellambura
• Keywords: Communications, ICC 2007, Limited Feedback, Orthogonal Space-time Codes, Space-time Codes