Joint Time Domain Channel and Channel Length Estimation for OFDM System

A joint channel impulse response (CIR) and channel length estimation method based on the correlation between the pilot signal with the received signal with cyclic prefix (CP) information is proposed. The proposed method is more efficient for OFDM systems with CP. The noise reduction is processed by taking the time averaging of two CIRs which can be determined by using the channel length information. Moreover, an effective channel length estimation method is also proposed without adding the complexity. The analysis and the simulation results show that the mean square error (MSE) and bit error rate (BER) performance of the proposed method is much better than the conventional correlation estimation (CCE) method both in the case with 16 QAM and QPSK modulation schemes under the same conditions. Moreover, the BER performance of the joint method is more closely to that of the ideal channel state information (CSI).