Phase equalization of multidimensional wave digital filters derived by rotation

Abstract In multidimensional filtering, the phase response is very important. It should be as linear as possible in a certain sense. This paper presents a numerical approach to equalize the phase of multidimensional wave digital filters whose reference filters are transformed from one-dimensional reference filters. This method is illustrated by an example of a two-dimensional wave digital filter whose transfer function has nearly circular symmetrical behavior. The parameters of the all-pass circuits for phase equalization are calculated.