Wideband coplanar waveguide to edges-even broadside-coupled stripline transition

A wideband transition between a coplanar waveguide (CPW) and an edges-even broadside-coupled stripline (EEBCS) is proposed. The simple transition is composed of a linear tapered line on the top layer and an electromagnetically-coupled Y-shaped stub on the bottom layer. A back-to-back, 50 CPW to 100 EEBCS transition is simulated, fabricated and measured. It is reported that a maximum insertion loss of 2.4 dB, a return loss better than 10 dB and average group delay of about 0.5 ns are obtained from 1.1 to 11.2 GHz for the transition.