Abstract

A well-known problem of the Orthogonal Frequency Division Multiplexing (OFDM) syste for mobile environment is the fading channel which degrades the system performance. Many methods have been proposed for channel estimation such as LS (Least Square), MMSE (Minimum Mean Square Error), Kalman Filter.…A fading channel with Doppler effect from the moving of receivers degrades system because of complicated changes and hard estimation. That is why traditional estimators do not have good performance. This paper introduces two new solutions of channel estimation for reducing Doppler Effect.

The first is that we combine between traditional estimation such as Least Square and self cancellation scheme. ^[1] The second is that we apply Unscented Kalman theory for channel estimation so that we can approximate channel estimation as a problem of nonlinear estimation. We compared these results together as well as with traditional estimator (Least Square). These algorithms had good results in simulations.