
Accession Number : ADA298948
Title : HighSpeed Fixed and FloatingPoint Implementation of DeltaOperator Formulated DiscreteTime Systems.
Descriptive Note : Interim rept. 1 Jan30 Jun 94,
Corporate Author : MIAMI UNIV CORAL GABLES FL
Personal Author(s) : Premaratne, Kamal ; Bauer, Peter H.
PDF Url : ADA298948
Report Date : 03 AUG 1994
Pagination or Media Count : 10
Abstract : This report addresses the analysis and design of finite word length implementations of linear timeinvariant deltaoperator formulated discretetime systems and the development of a 2D deltaoperator statespace model. It is shown that, in fixedpoint arithmetic, linear timeinvariant systems implemented with delta operator do not generally outperform their shiftoperator counterparts; they always show unstable limit cycle behavior and convergence to incorrect equilibria independent of realization and sampling time. Coefficient sensitivity is still superior. With floatingpoint arithmetic, deltaoperator implementations consistently perform better than their shiftoperator counterparts. They show superior quantization noise and sensitivity properties. Zero convergence problem of the fixedpoint case does not exist if the mantissa length is sufficiently large. Noting these attractive finite wordlength properties, the concept of deltaoperator has been extended to the multidimensional case. A 2D statespace model, the notions of gramians, and balanced realization have been introduced. As for the 1D case, sensitivity and roundoff noise behavior was analyzed. Realiviza tion that 1D case, sensitivity are equivalent to balanced realizations. The problem of directly checking stability in the deltadomain has also been addressed. (AN)
Descriptors : *MATHEMATICAL MODELS, *FLOATING POINT OPERATION, LINEAR SYSTEMS, STABILITY, COMPUTATIONS, TWO DIMENSIONAL, INPUT OUTPUT PROCESSING, MATHEMATICAL FILTERS, CONVERGENCE, DISCRETE DISTRIBUTION, OPERATORS(MATHEMATICS), ARITHMETIC, DIGITAL FILTERS.
Subject Categories : Operations Research
Distribution Statement : APPROVED FOR PUBLIC RELEASE