A subband adaptive filter with a variable analysis filter bank

Conventional subband adaptive digital filters (ADFs) using filter banks have shown performance degradation because of the non-ideal nature of the analysis filters. For this problem, we propose a new class of subband ADFs which has two kinds of analysis filter banks. We first claim that subband ADFs with the optimum analysis filter bank, which can minimize the least squares error at each bin, can be designed in accordance with the statistics of the signals. We also propose a practical type of subband ADF which requires no a priori knowledge of the the signals statistics. Several computer simulations are also given in order to show the efficiency of the proposed subband adaptive digital filters.