Analysis of Field Propagation Through a Multiport Frequency Selective Network Using Cavity Modeling Technique

Abstract

This paper presents the applicability of cavity modeling technique to analyze field propagation inside a multiport waveguide network. For a better understanding of the subject, we have considered a five-port quadraplexer as our target network. Field propagations within the network at different passband and stopband frequencies have been presented. The analysis has been verified by comparing the overall frequency response of the network with the available data in literature. The analysis demonstrates the field division at different junctions as well as field attenuation/propagation at different points of the network, which will be helpful for designing more complex and/or advanced multiport waveguide networks. It also demonstrates the presence of higher order modes at different discontinuities of the network and their effects on the respective field distributions.

Analysis of Field Propagation inside A Waveguide Diplexer using Cavity Model Analysis

“…If the scattered field is in the waveguide region then it is called a 'waveguide scattered field' whereas if the scattered field is in the cavity region then it is called the 'cavity scattered field'. The scattered field in the waveguide region can be derived using the modal expansion method [16][17][18] whereas the scattered field in the cavity regions can be derived using the Greens function approach [16,17,19]. The source field is the dominant TE10 mode and can be present in the input waveguide only (in this case in the region W1).…”

“…Applying the continuity condition of tangential magnetic fields, the boundary equations on the different apertures of the DOI: http://dx.doi.org/10.32452/IJAMT.2022.296300 © 2023 IJAMT network can be derived. The boundary equation will be in terms of unknown magnetic currents and can be solved using Galerkin's specialization of the method of moments [16,17,20]. This will provide the fields at different apertures and Sparameters of the network.…”

“…This paper presents a field-theoretic approach [16,17] that can be used to analyze the field propagation inside a diplexer network and understand the working principle of the network. Since a large number of diplexer networks are already available in open literature with excellent network characteristics, it felt useless to design another diplexer network.…”