Hypercomplex Bark-scale filter bank design based on allpass-phase specifications

With telephony and hearing aids in mind, we present in this research paper an I-channel Bark-scale filter bank approach (I = 2
^D
, D ϵ N) that employs a hypercomplex (i.e. multi-hyperbolic) allpass filter as a filter bank. Efficient computation is assured by maximal orthogonal decomposition of the selected multi-hyperbolic algebra. The main advantages of this approach are: i) parallel processing of the subband signals, ii) designability of arbitrarily non-uniform filter banks, and iii) robustness (= losslessness) as a result of the double complementarity of (hypercomplex) allpass functions.