Classical Discrete-Time Fourier Transform-Based Channel Estimation for MIMO-OFDM Systems in Vehicular Communications Technology
In this paper, the authors look at various time domain channel estimation methods with this constraint of null carriers at spectrum-borders. They show in detail howto gauge the importance of the "Border effect" depending on the number of null carriers, which may vary from one system to another. Thereby they assess the limit of the technique discussed when the number of null carriers is large. Finally the DFT with the truncated Singular Value Decomposition (SVD) technique is proposed to completely eliminate the impact of the null sub-carriers whatever their number. A technique for the determination of the truncation threshold for any MIMO-OFDM system is also proposed.