A new efficient decision-aided ISI canceler for mobile communication systems

Intersymbol interference (ISI) can be effectively cancelled by using a decision-aided canceler (DAC). Such a scheme exploits the fact that the introduced ISI may be adequately modeled as a linear combination of past and future decisions. Since future decisions are unavailable, a first stage is required, which provides tentative decisions to the second (the cancellation) stage. In the new DAC presented here, block adaptive schemes, implemented in the frequency domain, are used in both stages. The new DAC outperforms the existing DAC schemes in both steady-state performance and convergence speed and at the same time it exhibits a much lower computational complexity. Its good performance is retained even under hostile conditions such as those encountered in wideband mobile communication systems.