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IEEE Microwave and Guided Wave Letters
Volume 10 Number 12, December 2000

Table of Contents for this issue

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A New Coupling Structure for Dual Mode Dielectric Resonators

Giuseppe Macchiarella, Member, IEEE Massimo Fumagalli and Silvia C. d'Oro

Page 523.

Abstract:

A novel method for realizing coupling between two orthogonal HEM11 resonant modes in dielectric ring resonators is described. The coupling is obtained by means of a metallic strip located on the inner or on the outer boundary of the dielectric ring; a strong coupling is obtained, even with small width of the strip, in particular when the strip is on the inner boundary. The dual-mode resonator is then suitable for filtering applications, with normalized bandwidth requirements exceeding 1% (as in base station units for mobile communications), allowing a relevant reduction of the overall volume, at the expense of a small reduction of the unloaded Q. The novel coupling mechanism and the Q degradation produced have been studied both numerically (by using finite elements simulations) and experimentally (measurements from a prototype two-resonators filter are reported).

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