Synthesis of dual-mode in-line microwave rectangular filters with higher modes

Abstract

Satellite communications are used intensively today. Separating the different frequency channels requires high selectivity. Up to now, this high selectivity has been achieved by using circular filters placed in circular waveguides. However, circular waveguides require a complicated design process and are difficult to manufacture. In this article, a filtering method based on rectangular geometry and using the higher mode is presented. The synthesis procedure and its practical equivalent circuit are shown to create independent zeros to the right and/or left of the passband. To validate this new concept of filtering and the corresponding synthesis, applications on TE 10 /TE 30 in-line rectangular filters are presented. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE 15: 241-248, 2005.

Design of In-Line Dual-Mode Rectangular Waveguide Bandpass Filters Using Multiple Inductive Circular Posts

“…Comparing to results obtained in [15], up to 22% reduction in length and consequently in weight can be obtained. Another advantage of the proposed design is minimizing the number of discontinuities (i.e.…”

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Pseudo-elliptic substrate integrated waveguide filters with higher-order mode resonances

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