Equalization in filter bank based multicarrier systems

In this paper we consider filter bank based multicarrier systems, which provide better spectral shaping than DFT-based orthogonal frequency division multiplexing (OFDM) or discrete multitone (DMT) systems for the subchannels, as well as for the overall signal. Due to their better performance in case of narrowband interference, such techniques have received attention especially in the context of very high-speed digital subscriber line (VDSL) system development. However, the channel equalization for such systems is still an open problem. In this paper, it is demonstrated that filter bank based multicarrier systems are very sensitive to the nonlinear phase response of the channel. Alternative ways to perform the channel equalization are discussed. Also measurement results from real subscriber lines are presented and, based on these results, a two-step equalization approach is proposed