Transformer Coupling for MMICs

A monolithic microwave circuit technique that employs an aircore transformer has been demonstrated with key building blocks for sensor systems. This technique is completely compatible with planar GaAs fabrication processes used in the fabrication of high-density and high-yield circuits. The transformer coupling technique has been successfully implemented in the design of a 4 GHz, 200 mW transmitter IC and a base-band receiver IC each 1.0 × 1.5 mm. Test results from these circuits are presented.