A Subspace Method for Blind Channel Estimation in CP-free OFDM Systems

In this paper, a subspace method is proposed for blind channel estimation in orthogonalfrequency-division multiplexing (OFDM) systems over time-dispersive channel. The proposedmethod does not require a cyclic prefix (CP) and thus leading to higher spectral efficiency. Byexploiting the block Toeplitz structure of the channel matrix, the proposed blind estimationmethod performs satisfactorily with very few received OFDM blocks. Numerical simulationsdemonstrate the superior performance of the proposed algorithm over methods reported earlier inthe literature.