A New Adaptive Channel Estimation for Orthogonal Frequency Division Modulation in Power Line Communication

Orthogonal frequency division modulation (OFDM) is paid more and more attention in power line communication. Channel estimation is a key technique of OFDM system. In this paper, the LMS adaptive channel estimation is studied at first. Simulation and test show that, on the slow time-variant power line channel, LMS algorithm has high estimation performance, but it is quite sensitive to the abrupt attenuation of power line channel. In order to resolve this problem, an adaptive algorithm (called FLMS in this paper) combined with decision feedback method is proposed. The simulations indicate that FLMS is able to resist the abrupt channel attenuation effectively. It possesses more advantages than ordinary LMS algorithm in power line channel estimation, and, at the same time, it has nearly the same channel tracking performance as pilot-assisted LMS algorithm. With high channel tracking performance, adaptive channel estimation for OFDM system is very fit for power line communication