Research and Implementation of a Millimeter Wave Comb Fin Line Electronically Controlled Attenuator

An electronically controlled attenuator is designed to achieve millimeter wave signal power level control.The transmission line of the attenuator is waveguide fin line. The attenuation is achieved by paralleling the PIN diode in the slot of the fin line. In addition, a new vertical comb structure is used to suppress the energy leakage between the waveguide and the fin line. The whole circuit is compact and easy to process. After simulation, optimization and measurement, the insertion loss in Ka-band 1 GHz bandwidth is less than 2 dB, the maximum attenuation reaches to 32 dB, it has good attenuation performance.