Higher-Order (LT/QN) Vector Finite Elements for Waveguide Analysis

Abstract

The finite element (FE) formulation for waveguide discontinuity analysis is reviewed and extended to multiple, arbitrarily-oriented ports. Several higher-order vector elements - specifically hierarchal linear tangential/quadratic normal (LT/QN) - are compared, and the extensions required to incorporate LT/QN elements in the formulation are presented. The improved accuracy afforded by LT/QN elements compared to constant tangential/linear normal (CT/LN) elements is investigated by considering energy conservation in an empty waveguide. Results obtained using both CT/LN and LT/QN elements are also shown for a problem of engineering interest: an E-plane bend. Results for the LT/QN elements compare especially well to approximate analytical results using quite coarse meshes. The paper concludes with a discussion of the use of iterative solvers and possible convergence problems encountered when using higher-order elements.

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Document Details

Document Type
Technical Report
Publication Date
Mar 01, 2002
Accession Number
ADP012055

Entities

People

  • David B. Davidson

Organizations

  • Stellenbosch University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Accuracy
  • Cartesian Coordinates
  • Eigenvalues
  • Electric Fields
  • Electromagnetic Fields
  • Engineering
  • Finite Element Analysis
  • Frequency
  • Frequency Bands
  • Linear Algebra
  • Materials
  • New York
  • Three Dimensional
  • Two Dimensional
  • Waveguide Bends
  • Waveguides
  • X Band

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Microwave Engineering.