Influence of Slot width of Inclined Slot Coupled Waveguide Shunt Tee on Resonant Frequency

Abstract

The paper presents an analysis of waveguide Tee junction made by rectangular waveguides coupled through an inclined slot in the narrow wall. Such waveguide Tee junctions are used for power division applications. As per the open literature available, analysis of Waveguide Tee junction coupled through a longitudinal slot is carried out by several authors. However, no data is available for waveguide Tee junction coupled through an inclined slot. Such a junction is useful to reduce EMI problems due to cross polarized components in the radiated fields from coupled arm. In such a junction, the designer will an additional parameters namely inclination of slot to control admittance characteristics. This data is required for the design of an array for a specified radiation beam. In this work, analysis is presented to obtain variation of normalized conductance and normalized susceptance as a function of frequency for the resonant length. The analysis is made in terms of self-reaction and discontinuity in modal currents in the main guide as well as Tee arm. This structure is also useful to produce vertically polarized waves.  Its design requires the knowledge of admittance characteristics of the shunt Tee.  The results are numerically obtained for varied slot widths.  It is observed from the results that Slot width has a lot of influence on the admittance parameter and resonant frequency