A new modular VLSI filter architecture using computationally efficient recursive digital filter topology

The authors introduce a modular VLSI architecture for a novel linear-phase FIR (finite impulse response) filter structure. The proposed linear-phase FIR filters have a highly reduced number of general multiplications per sample compared to conventional FIR filters. The novel filter structure is based on an IIR subfilter whose infinite impulse response is truncated into a finite one. Although the subfilter has a nonlinear phase response, it can be made exactly linear by reversing the data stream in time and using the same filter again. Another possibility is to use a maximum-phase version of the FIR filter in cascade. The choice between different realizations depends on the filter specifications. In the general case the filter coefficients cannot be represented with the simple shift-and-add procedure and the time reversal technique should be used. The authors prefer the maximum-phase FIR alternative.<>