Blind channel estimation through redundant linear precoding for OFDM systems

A novel approach of blind channel estimation through redundant linear preceding for orthogonal frequency-division multiplexing (OFDM) is proposed. A redundant linear frequency-domain precoder is applied to each pair of blocks before they enter the OFDM system. With the aid of the introduced structure, the frequency-selective channel can be identified at the receiver through auto-correlation operations, singular value decomposition (SVD) and scalar ambiguity resolution. The proposed blind channel estimation method has low computation complexity and requires no prior statistical information of channel or noise. The redundant linear frequency-domain precoder is employed to identify the frequency-selective fading channels. And the proposed blind channel estimation method has high spectral efficiency because it requires no training sequence. Computer simulations have proved that this proposed blind channel estimation method can identify the frequency-selective channels perfectly and have a good performance.