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IEEE Transactions on Microwave Theory and Techniques
Volume 48 Number 12, December 2000

Table of Contents for this issue

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A Design Procedure for Bandstop Filters in Waveguides Supporting Multiple Propagating Modes

Christopher Alfred Wolfgang Vale, Student Member, IEEE Petrie Meyer, Member, IEEE and Keith Duncan Palmer Member, IEEE

Page 2496.

Abstract:

A design procedure for bandstop filters in waveguides supporting multiple propagating modes is presented in this paper. The method utilizes a cascade arrangement of resonant"block structures"to stop propagation of a number of modes across a specific band. These filters find particular application in dielectric heating facilities. The design is a two-step process:first, all the necessary block structures are assembled, and then they are cascaded to realize an optimally small filter that fulfills specifications. Two examples of designed filters are discussed. Both achieve better than 40-dB attenuation over a 5% bandwidth in the presence of five propagating modes. The measured results of one filter, realized at 19.1 GHz in WR-90, are shown to agree well with the predicted performance from the mode-matching-based analysis technique.

References

  1. A. Wexler, "Solution of waveguide discontinuities by modal analysis", IEEE Trans. Microwave Theory Tech., vol. MTT-15, pp.  509-517, Sept.  1967.
  2. R. Safavi-Naini and R. H. MacPhie, "On solving waveguide junction scattering problems by the conservation of complex power technique", IEEE Trans. Microwave Theory Tech., vol. MTT-29, pp.  337-343, Apr.   1981.
  3. A. S. Omar and K. Schünemann, "Transmission matrix representation of finline discontinuities", IEEE Trans. Microwave Theory Tech., vol. MTT-33, pp.  765-770, Sept.  1985.
  4. F. Alessandri, M. Mongiardo and R. Sorrentino, "Computer-aided design of beam forming networks for modern satellite antennas", IEEE Trans. Microwave Theory Tech., vol. 40, pp.  1117-1127, June  1992.
  5. W. Kasparek and G. A. Muller, "The wavenumber spectrometer-An alternative to the directional coupler for multimode analysis in oversize waveguides", Int. J. Electron., vol. 65, pp.  5-20, 1988.
  6. R. J. Vernon, W. R. Pickles, M. J. Buckley, F. Firouzbakht and J. A. Lorbeck, "Mode content determination of overmoded circular waveguides by open-end radiation pattern measurement", presented at the IEEE AP-S Int Symp, 1987.