Design and performance of GaAs MMIC CPW baluns using overlaid and spiral couplers

The design and performance of microwave and MM-wave baluns using multilayer GaAs MMIC technology is presented. For MM-wave designs a compact overlaid coupler is employed. For lower frequencies it is shown that novel spiral couplers can be used. Results for baluns operating at 30-40 GHz and 5-15 GHz are presented.