A Novel Subspace-based Blind Channel Estimation Algorithm in Space-Time Block Coded Zero-padded Systems with Few Received Blocks

• Main Authors: Bo-Fong Chou, 周柏夆
• Other Authors: 蘇柏青
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/95383045348035103949

碩士 === 國立臺灣大學 === 電信工程學研究所 === 101 === In this thesis, we studied subspace-based blind channel estimation in multiple-input-multiple-output (MIMO) zero-padded (ZP) systems whose transmitter is employed with a special case of space-time-block-codes (STBC), namely, the Alamouti codes. The proposed algorithm can be applied in such STBC-ZP systems with generalized precoders which are equivalent to, for example, zero-padded single carrier (SC-ZP) systems and zero-padded orthogonal frequency division multiplexing (ZP-OFDM) systems. The proposed method is capable of working with a small amount of received data by using the circulant permutation concept and forward and backward (FB) averaging techniques jointly. In the proposed method, we also introduce a new parameter called circulant repetition index. The performance of the proposed method can be slightly improved by choosing a circulant repetition index properly. The probability for the proposed method to work can be further increased by choosing circulant repetition index large than zero in ZP-OFDM systems without using FB technique. Compared with several algorithms in the recent literature, the proposed method possesses advantages in 1) better performance; 2) fewer required received blocks. Simulation results verified these advantages.