Synthesis of lossless ladder filters by interpolation and frequency-transformation methods

It is shown how the interpolation method can be combined with frequency transformation for the synthesis of lossless ladder filters. The algorithm avoids iterative procedures. The problem is treated in a clear and systematic manner, using a new polynomial operations concept; the arithmetical operations on polynomials in interpolation form are replaced by corresponding equivalent operations on transformed polynomials. The necessary set of procedures for the arithmetic operations on such transformed polynomials and their application are described in detail. The new combined algorithm is considerably faster than comparable methods and shows good accuracy