Skip to Main Content
A new low-loss CPW-based MMIC coupler is developed. Offset broadside coupling using the air gap between the two lines in employed to obtain tight coupling as well as low conductor loss. Moreover, the air-gap coupling is achieved using a standard MMIC airbridge process, eliminating the need for an additional dielectric process. The fabricated Ka-band coupler showed transmission and coupling losses of 3.6/spl plusmn/0.4 dB over a wide frequency range from 20 to 39 GHz. This is better than the previous CPW coupler loss in this frequency range.