An Ultra-Wideband Power Combining in Ridge Waveguide for Millimeter Wave

In this article, a novel and efficient ultra-wideband power-combining method over K (18–26 GHz) and Ka (26–40 GHz) band is presented. Ridge waveguide power combiners and contactless transition between ridge waveguide and double microstrip lines will be used in this method. By using this method, a 16-way power combiner system is designed to work in the bandwidth of 18–40 GHz through 3-D electromagnetic field simulation and optimization. A back-to-back configuration of this combiner system is manufactured. The measured power-combining efficiency is higher than 78% within the designed frequency. By using 16 GaAs monolithic-microwave integrated-circuit (MMIC) medium power amplifiers, the active combiner system produces up to a maximum power output of 3.9 W with a power variation of ±1.3 dB within the bandwidth of 18–40 GHz. The measured power added efficiency (PAE) within the operating bandwidth is up to 16%.