“…In general, channel estimation algorithms for single-input single-output (SISO) OFDM can be divided into two categories: non-blind channel estimation methods (using training sequence [7], pilots [8][9][10][11]) and blind/semi-blind channel estimation methods (exploiting virtual carriers [12], cyclostationarity [13], subspace method [12,[14][15][16], finite-alphabet method [17]). Compressive sensing methods [18,19] as well as other methods [20,21] have also been used for channel estimation in OFDM systems. Manuscript Several training sequence-based channel estimators were developed in [7], and pilot-aided channel estimation methods [8][9][10][11] in OFDM systems exploit some pilot symbols which are inserted at the given locations to estimate channel parameters.…”