Controllable Dual-BandE-Plane Waveguide T-Junction Using Extended S-Shaped Ring Resonators

In this novel application, an X-band E-plane waveguide T-junction with an inductive septum is modified in the form of a dual-band power divider using a slab of S-shaped ring resonators in each arm of the junction. Results obtained from measurement and numerical simulations of a specific structure are presented. The results show that the structure can be used in a wide frequency band below cut-off frequency of the hollow waveguide T-junction with low insertion loss. Also, by using finite element simulation, it is shown that the frequency range of each of the two bands of operation can be adjusted by changing the slab substrate properties, permittivity, thickness, and its position inside each waveguide.