Exact synthesis of LDI and LDD ladder filters

The low sensitivity property of lossless discrete integrator (LDI) low-pass ladder filters is shown to be preserved in lossless discrete differentiator (LDD) high-pass ladder filters [1]. The exact design method for LDI ladder filters given in [2] is further developed by introducing a set of closed-form design formulas for digital all-pole Chebyshev transfer functions. A new technique for improving the numerical accuracy in the synthesis procedure is introduced. Finally, a comprehensive LDI ladder filter design program is presented.