Performance comparison of TEQ design techniques for FDM ADSL

TEQ design to maximize the data rate for FDM ADSL channels is challenging due to the bandsplit filtering. In this paper, a performance comparison of several TEQ design techniques is presented for typical FDM channels. It is observed that (a) no single TEQ design criterion achieves the maximum performance, and (b) the performance is limited by the resulting TEQ design producing large variations in the passband region and/or emphasizing the stopband region. It is then shown that in many of these cases, better performance can be obtained by applying a spectral flatness constraint to the TEQ design. Additionally, we demonstrate that the dual TEQ and per tone equalizer are well suited to equalizing FDM ADSL systems.