Complexity Reduction for DRM System Using Time Domain Preprocessing

Inter-carrier-interference (ICI) phenomena in the orthogonal frequency division multiplexing (OFDM) systems complicates the channel estimation and equalization tasks at the receiver side when the number of carriers increases, since the minimum mean squared error (MMSE) and zero forcing (ZF) criterions require non-trivial matrix inversion. The complexity can be reduced without strongly affecting the performance using time domain windowing which squeezes the channel matrix into a small number of diagonals that have the strongest ICI coefficients. In this paper, a window is designed to maximize the signal-to-noise-plus interference ratio (SINR) according to digital radio mondiale (DRM) channel. Iterative algorithms for detecting the OFDM symbols are applied to further increase the system performance