Resolution Properties of the Fourier Method for Discontinuous Waves

Abstract

In this paper we discuss the wave-resolution properties of the Fourier approximation: of a wave function with discontinuities. It is well known that a minimum of two points per wave is needed to resolve a periodic wave function using Fourier expansions. For Chebyshev approximations of a wave function, a minimum of Pi points per wave is needed (3). Here we obtain an estimate for the minimum number of points per wave to resolve a discontinuous wave based on its Fourier coefficients. In our recent work on overcoming the Gibbs phenomenon, we have shown that the Fourier coefficients of a discontinuous function contain enough information to reconstruct with exponential accuracy the coefficients of a rapidly converging Gegenbauer expansion. We therefore study the resolution properties of a Gegenbauer expansion where both the number of terms and the order increase.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1992
Accession Number
ADA253883

Entities

People

  • Chi-Wang Shu
  • David Gottlieb

Tags

DTIC Thesaurus Topics

  • Analytic Functions
  • Applied Mathematics
  • Bessel Functions
  • Boundaries
  • Chebyshev Polynomials
  • Coefficients
  • Computations
  • Computers
  • Contracts
  • Errors
  • Fourier Series
  • Identities
  • Inequalities
  • Mathematics
  • Polynomials
  • Truncation
  • Wave Functions

Fields of Study

  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Image Processing and Computer Vision.