Subband adaptive filters have been proposed to avoid the drawbacks of slow convergence and high computational complexity associated with time domain adaptive filters. Subband processing introduces transmission delays caused by the filter bank and signal degradations due to aliasing effects. One efficient way to reduce the aliasing effects is to allow a higher sample rate than critically needed in the subbands and thus reduce subband signal degradation. We suggest a design method, for a uniform DFT filter bank with any over sampling factor, where the total filter bank group delay may be specified, and where the aliasing and magnitude/phase distortions are minimized.
En ny metod för design av översamplade filterbankar presenteras. Metoden minimerar vikningstermer inuti de olika subbanden. Dessa termer orsakar avvikelser från optimala lösningar varför det är önskvärt att minimera effekten av dessa.