Analysis of a new millimetre wave power combiner

A mm-wave power combining structure for two-terminal devices, consisting of an integrated 3-diode-module and a resonant cap in waveguide technique, is analyzed concerning impedance matching, modes of oscillation, stability and power generation. The monolithic realization of the module ensures symmetry and reproducibility, whereby parasitics are minimized. The rf-design of the structure forces in-phase operation of all three diodes, resulting in optimum power extraction. Theory is compared with experimental results at 91 GHz. The best measured result is 0.50W at 91 GHz with a conversion efficiency of 9%.