A high-power transient coaxial power combiner for nonlinear transmission lines

Summary form only given. Recent work on Coaxial Ferrimagnetic Nonlinear Transmissions Lines (NLTL) has been focused on developing an array of NLTLs for use as a solid-state High Power Microwave (HPM) source. The pulsed output of an NLTL requires a combiner that enables combining transient signals at voltage levels up to 50 kV. Existing combiner designs found in literature require resonant structures to achieve efficient power combination, an approach that fails for the short pulse transient signals generated by the NLTL. The novel coaxial combiner is an in-plane structure designed to combine two 50 Ω NLTLs into a single 25 Ω coaxial output which then uses a linear taper to transition back to 50 Ω. The combiner design was simulated using a transient Finite Element Method (FEM) model in COMSOL Multiphysics® and experimental results are compared with simulation. A four-way radial combiner based on the in-plane two-way design is simulated and the field stresses are examined to determine possible operational voltage levels for the four-way design.