Blind Channel Estimation and Equalization in OFDM System With Circular Precoding

This paper proposes a reliable and efficient blind channel estimation method and a linearly constrained minimum variance (LCMV) receiver with circular precoding for single transmitter and receiver antenna orthogonal frequency division multiplexing (OFDM) system. The proposed blind channel estimation method is based on the interesting cross-correlation property of the cyclic prefix (CP) in an OFDM symbol. Toeplitz structure induced in the cross-correlation matrix allows us to employ a simple and reliable method for extracting channel impulse response effectively. The LCMV optimization criterion is applied for symbol detection of the OFDM symbols. At the same time, a circular precoding scheme for minimizing the maximal power of the dominant interference plus noise in LCMV receiver is considered. In the simulation study, proposed method is compared with other circularly precoded scheme and it demonstrate the superior performance of the proposed method