Yield-Driven Design of Direct-Coupled Waveguide Filters with Minimum Use of Full Wave EM Solvers

Abstract

To reduce costly prototyping and allow for short design cycles in the design of tuningfree waveguide filters, it is important to be able to perform yield analysis in short time frames. For many filter topologies, this is infeasible by direct application of full wave EM solvers. In this paper, a simple and fast method for yield-driven design of direct-coupled waveguide filters with minimum use of full wave EM solvers is presented. The method is based on training a circuit model by including the sensitivities of each coupling to changes in dimensions and frequency. It is shown that this model gives accurate results for dimensional changes within typical production tolerances for waveguide components, and it is thus possible to perform fast tolerance analysis with high accuracy for yield-driven design. Examples of tolerance analysis for some filter topologies are shown. Also included is a comparison with measurements.

Rigorous derivation of lossy equivalent circuit for narrowband waveguide direct‐coupled‐cavity filters

“…Another application of the theory developed in this work is the yield analysis of the designed filter with manufacturing tolerances. It can be presented as an extension to the work in [19]. However, using the equivalent circuit theory derived in this work the yield analysis of the filter can be performed with an accurate evaluation of the resulting losses.…”

“…The resonator has been split in two symmetric halves and only one has been taken. The resonant condition is given by (19)…”

Techniques for loss reduction in waveguide filters

“…Another application of the theory developed in this work is the yield analysis of the designed filter with manufacturing tolerances. It can be presented as an extension to the work in [Folgero and Kocbach, 2003]. However, using the equivalent circuit theory derived in this work the yield analysis of the filter can be performed with an accurate evaluation of the resulting losses.…”