A SCPW Coupled Line Directional Coupler with Broadside Coupling

In this report, a miniaturized suspended coplanar waveguide (SCPW) coupled line directional coupler with broadside coupling (BC) is proposed, and which has the characteristics of double-sided wiring and multi-layer stacking. The directional coupler has a center frequency of 2.89GHz, a relative bandwidth of 17.3%, a phase balance of ±1°, and the in-band insertion loss and coupling factor can be maintained between 2.95dB-3.3dB. The proposed coupler also has good flatness and high directionality.