On the design and realization of a class of tunable 2-D digital filters
X. Nie, Rolf Unbehauen, B. Anhaupl · 1991
The extended McClellan transformation has been applied to transform a 1-D zero-phase FIR (finite impulse response) filter into a 2-D tunable zero-phase IIR (infinite impulse response) filter. By tuning a few parameters, one can obtain a class of 2-D filters with various band edge contours of nearly elliptic or nearly circular symmetry. This class of filters has been realized as a cascade of an anti-causal IIR filter and a causal all-pass filter. This realization shows two advantages: the quantization noise due to the finite word length is relatively low and scaling of the 2-D structure is no longer necessary.>