A novel dual-frequency phase inverter

In this letter, a novel dual-frequency phase inverter is proposed. The interdigital striplines and metallic vias are used to obtain 180 degree phase shift. The different length of the slotlines in the ground can obtain different operation frequencies. The structure of the phase inverter is simple and can be realized with ordinary microwave integrated circuit (MIC) fabrication process. The two simulations show the phase inverter can work at two different frequencies.