A novel maximum likelihood channel estimation for OFDM systems
Authors: Zhang, J.K., Chen, E.Q., Mu, X.M. and Qi, L.
Journal: Binggong Xuebao/Acta Armamentarii
To acquire a better performance, the receiver in orthogonal frequency division multiplexing (OFDM) systems must estimate the channel state information. Maximum likelihood (ML) channel estimation for OFDM systems needs to know the effective length of channel impulse response for achieving optimum performance. Existing ML channel estimation schemes do not offer an available scheme to track the variation in effective length of channel impulse response. Based on the analysis that the ML channel estimator performance depends on the assumed effective length of channel impulse response, a modified ML channel estimator which combines the ML estimation with a policy of line search was proposed to improve the precision of the ML channel estimator. The simulated results under the multi-path Rayleigh channel show that the improved algorithm in this paper can track effective length of channel impulse response effectively and improve performance of the ML channel estimator.