Digital filter-banks for transform computations and other applications

A generalized filtering structure is developed which is based on the N×N basis matrix of an arbitrary transform. The filtering structure finds application as an efficient sliding transformer of data because it has the low complexity of the associated frequency sampling structure, but has much better sensitivity properties. It can also be used as a filterbank in a multirate filtering system. The analysis filters are seen to require very few multipliers (the synthesis filters are finite impulse response with, at most, as many taps as there are channels in the filterbank) and at the same time provide ≈40 dB attenuation of the nearest sidelobe