NEW METHOD FOR DESIGNING TWO-DIMENSIONAL RECURSIVE DIGITAL FILTERS WITH MAGNITUDE AND PHASE ERROR CRITERIA.

A new method concerning two-dimensional (2-D) recursive digital filter design is presented. The complex frequency response error is decomposed into its corresponding real part and imaginary part errors; in this way the magnitude and phase error criteria are established. A set of analytic derivatives for the complex frequency response error and stability error is then derived. Through these formulas, the error derivatives required in the optimization procedure can be computed analytically rather than numerically. This results in saving design time significantly. Several examples are given.