A simple subspace-based blind channel estimation for OFDM systems

In this paper, we consider the problem of blind channel estimation for single-input single-out (SISO) orthogonal frequency-division multiplexing (OFDM) systems via second order statistics (SOS) only. Based on the assumption that the transmitted symbols are independent and identically distributed (i.i.d), we develop a simple subspace based blind channel estimation technique by utilizing a non-redundant linear block precoding. The proposed method offers improved performance over the existing method using similar precoding technique. Additionally, the design criteria for the precoders by which the performance can be greatly improved is discussed, and the stochastic Cramer-Rao bound (CRB) is derived. The numerical results clearly show the effectiveness of our proposed algorithm