2 x 2 quasi-optical power combiner array at 20 GHz

The design concept and the experimental results of a power combiner made of two FET oscillators for a quasi-optical array are reported. In order to demonstrate an approach by a quasi-optical method with a strongly coupled oscillator configuration, a 2 x 2 planar array is fabricated using a direct connection through a microstrip line. The input impedance of the slot radiator is taken into account as a circuit element to investigate the passive part of the array. In order to accomplish a sum radiation pattern, the length of the microstrip feed lines are regulated. At an operating frequency of 20 GHz, sum radiation patterns were observed in both the H-plane and the E-plane.