Wideband lumped element equivalent circuit model for waveguide slots and applications

A parallel LC equivalent circuit model for rectangular waveguide slots is obtained through the MoM analysis of a waveguide slot coupler problem. The values of the lumped LC elements are virtually constant over the frequency range of interest (the X-band) for specific waveguide and slot dimensions. Obtained through the analysis of a simple waveguide coupling problem, the equivalent circuit model is used to analyze more complicated structures, such as slot coupler arrays and slot-based waveguide filters. The results obtained for these structures through the circuit analysis are verified using the MoM and the FDTD techniques, and exhibit excellent agreement over a wide band of frequencies.