Experimental characterization of EC-CPW transmission lines and passive components for 60-GHz CMOS radios

In this work, we propose the use of elevated center coplanar waveguide (EC-CPW) transmission lines in CMOS technology to alleviate the technology limitations of achieving extreme impedances with conventional CPW lines, particularly, high impedances. High impedance lines are required to facilitate the design of matching networks and to reduce the size of the passive components by utilizing capacitively loaded high-impedance lines. This paper presents the measured and simulated performance of these lines and their implementation in building a 60 GHz reduced-size 90° coupler. The coupler´s size is 0.102 mm² and it is well suited for use in the design of radio front-ends of 60 GHz high data-rate wireless systems.