Modular Dual-Ridged Horn Antenna Design for EMC Testing in 14.9 to 44 GHz Range

To meet the specific requirements of Electromagnetic Compatibility (EMC) tests in the 15 to 43.5 GHz frequency range, a modular dual-ridged horn antenna design is introduced. This design optimizes the transition from a coaxial RF connector to a circular waveguide, ensuring broadband performance and minimizing unwanted radiation modes. The antenna features three interchangeable radiators, each offering distinct radiation patterns optimized for constant beamwidth and symmetry across the frequency range. Detailed geometries are provided in three orthogonal cross-sections, highlighting key components. Utilizing waveguide technology, the horn antenna achieves low loss and high-power handling. A formula for estimating peak-power handling, derived from electromagnetic simulations under environmental conditions, is presented. This formula enabled a fourfold increase in power handling through geometry adjustments in critical antenna parts. Simulation results for reflection coefficient, radiation pattern, and efficiency are validated by prototype measurements, showing excellent agreement. The antenna parameters are applied to estimate RF performance in Electromagnetic Interference (EMI) and Susceptibility (EMS) test systems, using realistic RF component and instrument parameters.