A subspace blind channel estimation method for OFDM systems without cyclic prefix

We propose a subspace based blind channel estimation method for OFDM systems over a time-dispersive channel. Our approach is motivated by the resemblance of the multichannel signal model resulting from oversampling (or use of multiple receive sensors) of the received OFDM signal to that in a conventional single carrier system (Moulines et al. 1995). The proposed algorithm distinguishes itself from many previously reported channel estimation methods by the elimination of the cyclic prefix (CP), thereby leading to higher channel utilization. Comparison of the proposed method with other two reported subspace channel estimation methods (Heath and Giannakis 1999; Xiaodong Cai and Akansu 2000) is presented by computer simulations to support its effectiveness.