A new adaptive intersubband tap-assignment algorithm for subband adaptive filters

This paper proposes a new subband adaptive filtering algorithm with intersubband tap assignment. The number of taps for each subband adaptive filter is adaptively controlled based on a sum of squared coefficients to the impulse-response tail of the unknown system. The sum is weighted by the input reference signal power to reflect its power imbalance. For rapid convergence of intersubband tap assignment, a time-varying number is newly introduced as the tap-redistribution step-size. This variable is controlled based on repeated redistribution of the maximum number of taps to the same subband. For colored signals, the proposed algorithm reduces the convergence time for intersubband tap-assignment by more than 60% compared with a fixed tap-redistribution step-size. It is insensitive to parameter-selection and has good capability to track a path change. It is also shown that the proposed algorithm is effective for real speech signals