New Methods for Improving the Pole-Zero Analysis Accuracy

摘要

An optimal pivoting strategy of the algorithm that reduces the general eigenvalue problem to the standard one is suggested for both full-and sparse-matrix procedures. The algorithm increases the accuracy of the semisymbolic analysis, especially for resonant and/or large-scale electronic circuits. A novel technique is also incorporated recognizing multiple poles or zeros, which are often computed inaccurately by the standard algorithms. A new type of this procedure called secondary root polishing is described in the paper. The accuracy is further increased using longer numerical data. First, the "long double" precision (available in many C/C++ compilers) is utilized. Second, a novel application of a suitable multiple-precision arithmetic library is suggested. The algorithms were checked on various electronic circuits.