A study of SPT-term distribution of CSD numbers and its application for designing fixed-point linear phase FIR filters

The distribution of the signed-powers-of-two (SPT) terms of canonical signed digit (CSD) numbers is nonuniform. In this paper, the author shows an explicit representation of this distribution. Based on this distribution, an algorithm is proposed for designing fixed-point linear phase FIR filters with CSD coefficients. Design examples demonstrate that the algorithm can produce filters using fewer SPT terms than other methods.