Realization of a class of two-dimensional analog ladders with applications to wave digital filters

Necessary and sufficient conditions are obtained for the realization of a class of two-variable analog transfer functions. The transfer function is realized as a resistively-terminated two-port consisting of a cascade of P1and P2-variable lossless two-ports each having all of its transmission zeros at Pi=0 or pi=∞ (i=1,2), It is shown how these analog realizations may be used to realize two-dimensional wave digital filters.