Synthesis of digital filters with very low sensitivity of the frequency response to the change of the cofficients
Pierre Duhamel · 2005
The following question provided motivation for this paper : - given some frequency specifications to be met by the implemented filter (taking into account the variations of the coefficients), is it better to implement the usual transfer functions with optimum magnitude in the Chebyshev sense, or to implement functions exhibiting a low sensitivity frequency response to the change of the coefficients, perhaps with non-optimum characteristics ? Two methods of synthesis taking into account some measure of the sensitivity, in the case of low-pass (or high-pass) filters are presented. - the first one, in the case of transversal filters, is based on a linear-programming approach. -the second one, in the case of recursive filters, is based on a procedure similar to the one presented in (2), Results demonstrating the advantage of such an approach in the case of CCD recursive filtering are provided.