Optimum-Weighted RLS Channel Estimation for Time-Varying Fast Fading MIMO Channels

A multiple-input multiple-output (MIMO) system, where multiple antennas are used at both transmitter and receiver, has been a promising technique for realizing highspeed wireless communications. In mobile communications, we often experience a considerable signal fluctuation due to time- varying fading channels. In this paper, we derive an optimum- weighted least-squares channel estimation considering the spatial correlation as well as the channel dynamics, and propose an efficient recursive method for channel tracking.