학술논문

Numerical Inverse Transformation Methods for Z-Transform
Document Type
article
Source
Mathematics, Vol 8, Iss 4, p 556 (2020)
Subject
inverse Z-transformation
numerical analysis
contour integral
finite order approximation
matrix geometric distribution
Mathematics
QA1-939
Language
English
ISSN
2227-7390
Abstract
Numerical inverse Z-transformation (NIZT) methods have been efficiently used in engineering practice for a long time. In this paper, we compare the abilities of the most widely used NIZT methods, and propose a new variant of a classic NIZT method based on contour integral approximation, which is efficient when the point of interest (at which the value of the function is needed) is smaller than the order of the NIZT method. We also introduce a vastly different NIZT method based on concentrated matrix geometric (CMG) distributions that tackles the limitations of many of the classic methods when the point of interest is larger than the order of the NIZT method.