REPRESENTATION AND ANALYSIS OF SIGNALS PART XV. MATCHED EXPONENTS FOR THE REPRESENTATION OF SIGNALS,

Abstract

Approximation by sums of exponentials is con sidered from various points of view, such as the time-domain approximation problem of network synthesis, in which an analytic time function is to be approximated, or situations in which dis crete measured values of some dynamic process are to be smoothed and fitted using an ex ponential model. Specifically, we consider determination of 2N possibly complex constants (A(j),s(j)), such that for given N and f(t) or (f(i)), one or the other of two integral ex pressions is minimum over both the (A(j)) and the (s(j)). Prony's method for approximate determin ation of the exponents is exhaustively reviewed in all its forms. It is found that the integral expressions are rather insensitive functions of the (s(j)), making direct minimization difficult. For the continuous case, a new scalar function of the (s(j)) is found, which vanishes if and only if one of the expressions is a relative minimum or maximum. The computational advantages afforded by this property allow construction of a practical iterative process leading to the true optimum exponents. The procedure is illustrated for the continuous case, and extensions to the discrete case are discussed. (Author)

Document Details

Document Type
Technical Report
Publication Date
Apr 30, 1963
Accession Number
AD0411431

Entities

People

  • Robert N. Mcdonough

Organizations

  • Johns Hopkins University

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Construction
  • Integrals
  • Scalar Functions
  • Time Domain

Fields of Study

  • Mathematics

Readers

  • Analytical Mechanics
  • Approximation Theory.
  • Snow Cover Descriptors for Reptiles and Their Illustrations.