Reduced-rank adaptive time-domain channel estimation for OFDM systems

In this paper, we consider a reduced-rank adaptive channel estimation for Orthogonal Frequency Division Multiplexing (OFDM) systems. The pilot-aided channel estimation is rawly carried out in the time domain, which is shown to have the better performance compared to the frequencydomain estimator. The adaptive modified Least Mean Square (LMS) algorithm is then applied to further improve the estimates of the channel coefficients. In order to attain lower complexity as well as fast convergence, a reduced-rank technique is also applied to the adaptive algorithm.