Subspace based blind channel estimation for OFDM by exploiting virtual carrier

In this paper, a new subspace based blind channel estimation method is proposed for OFDM systems over a time-dispersive channel. The proposed algorithm exploits the presence of virtual carriers and eliminates the cyclic prefix; thereby leading to higher channel utilization than most previously reported cyclic prefix based estimators. A sufficient condition on the channel identifiability is developed. Comparison with two other cyclic prefix based subspace methods is presented via computer simulations to support the effectiveness of the proposed method.