Multimode equivalent network representation for junctions between coaxial and circular waveguides

In this article we present two contributions to the study of coaxial waveguide structures. First, we present an efficient and accurate technique to evaluate the modes in the coaxial waveguides; second, we analyze junctions involving coaxial and circular waveguides using the multimode equivalent network representation. Numerical and experimental results are presented, showing good agreement. © 1997 John Wiley & Sons, Inc. Int J Microwave Millimeter-Wave CAE 7: 180–194, 1997.     

A strategy for the efficient full-wave description of complex waveguide networks

The mode-matching analysis of rectangular waveguide networks requires a complex segmentation of the structure into simple elements. The way these elements are connected has a strong influence on the computing performance of the code. Moreover, for complex structures the size of the coefficient matrix of the main system can easily reach unaffordable dimensions, so that the use of an efficient solving strategy becomes indispensable. A new approach to the optimum automatic choice of the interconnections is presented, leading to a highly stable and outperforming method of analysis. A Butler 4 × 4 matrix, with six branch guide couplers and four phase shifters, containing 336 uniform waveguide sections and bifurcations, has been studied, and the presented strategy has allowed a performance increase up to two orders of magnitude. © 1996 John Wiley & Sons, Inc.